Tunnel Thruster
high
727 models total
A tunnel thruster is a fixed propeller in a transverse tunnel, distinct from azimuth or retractable units because it cannot steer - it only pushes sideways, port or starboard, at one fixed location in the hull.
Read more — Tunnel Thruster explained ▾
What Defines a Tunnel Thruster
A tunnel thruster is a propeller mounted inside a straight transverse tunnel cut through the hull, close to the bow or stern. Unlike azimuth thrusters or retractable units, it cannot rotate or train; it only produces thrust along the tunnel's fixed axis, port or starboard, by reversing the propeller pitch or its direction of rotation. That simplicity is the whole point: a tunnel unit is cheaper to install, has no exposed steerable gearbox below the hull, and is the default choice wherever the vessel only needs lateral push for berthing rather than full manoeuvring or dynamic positioning capability.
Main components
Tunnel
A steel tube welded into the hull, sized and positioned per naval architecture calculations; a poorly located tunnel loses thrust to hull interaction and can generate noticeable vibration.
Propeller
Fixed-pitch or controllable-pitch, typically four or five bladed. Controllable-pitch units reverse thrust by changing blade angle at constant shaft speed, which is faster and gentler on the drivetrain than reversing a fixed-pitch propeller's rotation.
Drive motor
Electric motor, hydraulic motor, or direct diesel drive through a right-angle gearbox. Electric drives dominate because they start and reverse quickly and integrate cleanly with the ship's power management system.
Gearbox and seals
A right-angle gearbox transmits drive from the motor shaft to the horizontal propeller shaft. Shaft seals keep sea water out of the gearbox and tunnel; seal failure is one of the most common causes of thruster downtime.
Selection and sizing
Thruster capacity is chosen from the manoeuvring requirement, not from engine room space:
- Bollard pull thrust in kN, derived from the vessel's windage area and the required transverse speed for berthing without tug assistance
- Motor power, typically a few hundred kW on coastal vessels up to several MW on large cruise ships and offshore vessels needing dynamic positioning capability
- Tunnel diameter and length-to-diameter ratio, which affects thrust efficiency and flow noise
- Fixed-pitch versus controllable-pitch, driven by how often the thruster starts and stops and whether soft manoeuvring is needed
Class and regulatory requirements
Classification societies require thruster tunnels to meet minimum submersion depth so the propeller does not draw air and cavitate in ballast condition, and they set structural requirements for the tunnel-to-hull connection. Where a thruster is counted toward a dynamic positioning notation, class rules require independent power feeds and redundancy appropriate to the DP class assigned. Periodic survey covers the drive motor, gearbox oil condition, seal integrity and, at dry-docking, the tunnel grid and propeller for damage or fouling.
Typical faults
- Seal leakage - worn shaft seals let sea water into the gearbox, contaminating the oil and accelerating bearing wear
- Cavitation erosion - operating in light ballast with insufficient submersion pits the propeller blades and reduces thrust over time
- Controllable-pitch hub hydraulic failure - loss of pitch control oil pressure leaves the blades stuck at an uncontrolled angle
- Debris strike - rope, fishing gear or ice entering the tunnel bends blades or jams the propeller
- Motor overheating - repeated short bursts during berthing without cooldown time trips thermal protection
What to look for in a supplier
- Documented bollard pull test results at the rated tunnel submersion, not just calculated figures
- Gearbox and seal spare parts held regionally, since a thruster failure often strands a vessel that depends on it for berthing
- Class approval of the tunnel structural design and drive train together, not as separate items
- Noise and vibration data if the tunnel sits near accommodation spaces
Log every thruster start with duration and current draw; a slow upward creep in running current over weeks, well before an alarm trips, is usually the first sign of a seal or bearing problem developing in the gearbox.
4000h
Service Interval
5 yr
Class Survey
25 yr
Typical Lifetime
Typical Manufacturers
Brunvoll
Rolls-Royce
Wartsila
Kawasaki
26 manufacturers · 727 models
Thrustmaster of Texas, Inc.
80 ✓ 36 verified
TM-TT-50 bow
unverified
· 50.0 kW
· tunnel thruster
Power (kW)
50
Thrust (kN)
6.0
Diameter (mm)
540
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Compact 540 mm diameter fits in moderate‑size hulls without excessive structural reinforcement
- 50 kW power provides sufficient thrust (6 kN) for vessels up to ~100 m LOA in calm conditions
- Integrated tunnel design offers good protection of the propeller and reduced fouling
- Relatively simple installation compared with azimuth thrusters
- Low maintenance due to sealed motor and straightforward duct geometry
Weaknesses
- Limited thrust makes it unsuitable for large tankers, bulk carriers or vessels requiring DP‑class maneuvering
- Performance drops in heavy seas or strong currents; cavitation may appear at high RPM
- Bow‑only configuration limits redundancy – loss of the unit reduces overall handling capability
- Hull penetration required for duct installation can affect structural integrity if not properly reinforced
- Noise and vibration levels higher than some newer pod‑type thrusters
Typical Vessels:
Coastal ferriesOffshore supply vessels (OSV)Workboats / crew transfer vesselsSmall container ships (up to ~100 m)Passenger cruise liners (mid‑size) for improved docking
Decision Guide: Choose the TM-TT-50 if you need a reliable, compact bow thruster for vessels up to about 100 m that operate mainly in sheltered waters and require modest thrust without the cost of larger azimuth units. Avoid it on very large ships, DP‑required platforms, or where high thrust under adverse conditions is critical.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
TM-TT-50 stern
unverified
· 50.0 kW
· tunnel thruster
Power (kW)
50
Thrust (kN)
6.0
Diameter (mm)
540
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Compact 540 mm tunnel diameter fits in limited hull spaces
- Moderate power (50 kW) balances fuel consumption with useful thrust for small‑to‑mid size vessels
- Integrated control interface compatible with most bridge navigation systems
- Robust stainless‑steel housing designed for marine corrosion environments
Weaknesses
- Maximum thrust of 6 kN may be insufficient for large tankers or high‑wind conditions
- Fixed‑pitch propeller design limits efficiency at very low speeds
- No published data on noise or vibration levels, which could affect crew comfort
- Lack of documented certifications (e.g., IMO D‑2) may require additional class approval
Typical Vessels:
Coastal cargo vesselsOffshore supply shipsWorkboats and tugs up to 3,000 gtSmall passenger ferries
Decision Guide: Choose if: you need a compact, moderate‑power stern thruster for vessels under ~3,000 gt where space is limited and fuel efficiency is a priority. Avoid if: the vessel requires higher thrust (>8 kN), operates in extreme weather, or must meet specific class certifications that are not documented for this model.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
TM-TT-75 bow
unverified
· 75.0 kW
Power (kW)
75
Thrust (kN)
9.0
Diameter (mm)
560
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (9 kN at 75 kW)
- Relatively small tunnel diameter (560 mm) eases hull integration
- Electric drive provides precise, low‑maintenance operation
- Standard bow installation simplifies retrofits on existing vessels
Weaknesses
- Limited thrust may be insufficient for very large ships or high‑wind conditions
- Hull penetration required; structural reinforcement may add cost
- Performance data not fully verified – certification status unclear
- Power demand of 75 kW can impact vessel electrical load management
Typical Vessels:
Offshore supply vesselFerryMedium‑size container ship (up to ~150 m)Coastal bulk carrierYacht
Decision Guide: Choose if: you need a moderate‑power bow thruster for vessels up to ~150 m, space is limited and an electric drive is preferred, and you can accommodate hull modifications. Avoid if: the vessel requires higher thrust levels, strict class approvals are mandatory, or power availability on board is constrained.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
TM-TT-75 stern
unverified
· 75.0 kW
· tunnel thruster
Power (kW)
75
Thrust (kN)
9.0
Diameter (mm)
560
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Compact 560 mm duct fits in vessels with limited hull space
- High thrust‑to‑power ratio for its class (9 kN @ 75 kW)
- Direct‑drive electric motor provides quick response and low emissions
- Standardized mounting interface simplifies installation on new builds or retrofits
Weaknesses
- Maximum thrust of 9 kN may be insufficient for larger vessels or high‑wind conditions
- Potential cavitation at high RPMs, requiring careful propeller selection
- Maintenance access to bearings and seals can be limited in tight stern spaces
- No published ice‑class certification limits use in polar regions
Typical Vessels:
Offshore supply vesselFerryCoastal cargo shipSmall container feederWorkboat / tug (light duty)
Decision Guide: Choose if you need a moderate‑power stern thruster for vessels up to ~2,000 GT where space is at a premium and electric drive is preferred. Avoid if the vessel requires high thrust (>12 kN), operates in ice or extreme weather, or must meet specific class approvals that are not documented for this model.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
TM-TT-100 bow
unverified
· 100.0 kW
· tunnel thruster
Power (kW)
100
Thrust (kN)
12.0
Diameter (mm)
580
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (12 kN) relative to its power rating
- Large 580 mm tunnel diameter provides efficient water flow and reduced cavitation
- Compact footprint compared with external azimuth pods for bow installation
- Suitable for vessels that require precise low‑speed handling such as DP‑assisted ships
Weaknesses
- Diameter of 580 mm may require significant hull penetration and reinforcement
- 100 kW power demand can increase overall fuel consumption on smaller vessels
- Limited to bow locations; not readily adaptable for stern use without redesign
- No publicly documented certification or class approval information
Typical Vessels:
Offshore supply vesselFerryContainer feederCoastal tankerDynamic positioning workboat
Decision Guide: Choose if: you need a high‑thrust bow thruster for vessels up to ~5,000 gt and have sufficient hull space for a 580 mm tunnel. Avoid if: hull modifications are prohibitive, power budget is tight, or class approval documentation is required before installation.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
TM-TT-100 stern
unverified
· 100.0 kW
· tunnel thruster
Power (kW)
100
Thrust (kN)
12.0
Diameter (mm)
580
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (12 kN at 100 kW)
- Compact tunnel diameter of 580 mm fits vessels with limited hull space
- Stern mounting simplifies integration with existing propulsion layouts
Weaknesses
- 100 kW power demand may require dedicated generator capacity on smaller ships
- Maximum thrust of 12 kN may be insufficient for very large vessels or extreme weather conditions
- Tunnel geometry can be prone to cavitation in shallow‑water operations
Typical Vessels:
Offshore supply vesselFerrySmall container ship (up to ~30,000 DWT)Coastal bulk carrier
Decision Guide: Choose if: you need a moderate‑power stern thruster for vessels up to ~30 kt deadweight where hull space is at a premium and 12 kN thrust meets maneuverability requirements. Avoid if: the vessel requires higher thrust (>15 kN), operates in very shallow water prone to cavitation, or has limited electrical generation capacity.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
TM-TT-150 bow
unverified
· 150.0 kW
· tunnel thruster
Power (kW)
150
Thrust (kN)
18.0
Diameter (mm)
620
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (18 kN) relative to its power rating
- Compact tunnel design fits within standard bow sections
- Direct water flow through the tunnel reduces cavitation risk
- Integrated control interface compatible with common bridge systems
Weaknesses
- Requires a relatively large hull opening (≈620 mm diameter)
- Higher power consumption compared with smaller‑rated thrusters
- Maintenance of bearings and seals can be intensive on high‑usage vessels
- Limited effectiveness in very deep drafts where water flow is constrained
Typical Vessels:
Offshore supply vesselFerryWorkboatMedium‑size container feeder
Decision Guide: Choose if you need strong bow thrust for vessels up to ~100 m LOA and have sufficient hull space for a 620 mm tunnel. Avoid if vessel power budget is tight, draft is deep, or an azimuth thruster is required for 360° maneuverability.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
TM-TT-150 stern
unverified
· 150.0 kW
· tunnel thruster
Power (kW)
150
Thrust (kN)
18.0
Diameter (mm)
620
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (18 kN from 150 kW) improves low‑speed handling.
- Relatively compact 620 mm tunnel fits in many medium‑size hulls without excessive structural modification.
- Robust, simple construction typical of tunnel thrusters leads to lower maintenance compared with more complex azimuth units.
- Stern placement reduces interference with bow thruster flow and can aid in backing maneuvers.
Weaknesses
- 150 kW power demand may require substantial electrical generation capacity on smaller vessels.
- Tunnel diameter limits installation to hulls that can accommodate a 620 mm opening, restricting use on very narrow or shallow drafts.
- Fixed‑direction thrust (no 360° rotation) may be less versatile than azimuth thrusters for certain DP operations.
- Potential for higher acoustic signature compared with some low‑noise azimuth designs.
Typical Vessels:
Offshore Support VesselFerrySmall to medium Container ShipCruise ship tenderCoastal bulk carrier
Decision Guide: Choose if you need strong, reliable lateral thrust at the stern for docking or DP assistance on a vessel that can accommodate a 620 mm tunnel and has sufficient electrical power. Avoid if vessel size or draft restricts tunnel installation, if low acoustic signature is critical, or if a fully rotatable azimuth thruster would better meet maneuverability requirements.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
TM-TT-200 bow
unverified
· 200.0 kW
· tunnel thruster
Power (kW)
200
Thrust (kN)
24.0
Diameter (mm)
660
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (24 kN @ 200 kW) for its size class
- Relatively small tunnel diameter (660 mm) eases hull integration on medium‑size vessels
- Robust, low‑maintenance electric drive suitable for continuous DP operation
- Standardized control interface compatible with most ship bridge systems
Weaknesses
- 200 kW electrical demand may require upgrades to existing power distribution on older ships
- Fixed tunnel orientation limits thrust vectoring compared with azimuth units
- Installation requires precise hull cut‑out and sealing; retrofit can be labour intensive
- Potential for cavitation noise at high RPM, which may affect passenger comfort on cruise vessels
Typical Vessels:
Offshore Supply VesselFerryCruise Ship (mid‑size)Container Ship (up to ~200 m LOA)Bulk Carrier (medium tonnage)
Decision Guide: Choose if you need a reliable, high‑thrust bow thruster for vessels up to about 200 m length where hull space is limited and electric power is available. Avoid if the ship relies on low‑power electrical systems, requires full 360° thrust vectoring, or has strict noise‑abatement constraints that favor azimuth or pump‑jet solutions.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
TM-TT-200 stern
unverified
· 200.0 kW
· Tunnel thruster
Power (kW)
200
Thrust (kN)
24.0
Diameter (mm)
660
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (24 kN) relative to its 200 kW power rating
- Compact 660 mm tunnel reduces hull penetration and internal space loss
- Robust, sealed construction suited for harsh marine environments
- Standard electric drive simplifies integration with shipboard power systems
- Designed specifically for stern installation, improving aft maneuverability
Weaknesses
- Fixed tunnel geometry offers less directional flexibility than azimuth units
- Significant hull penetration (660 mm) requires careful structural reinforcement
- 200 kW electrical demand may be excessive for smaller vessels with limited power generation
- No inherent redundancy; a single motor failure disables the thruster
- Spare‑part availability tied to Thrustmaster Marine dealer network
Typical Vessels:
Medium tankerContainer shipBulk carrierOffshore supply vesselCruise ferry
Decision Guide: Choose if you need strong, reliable stern thrust for vessels up to roughly 30 000 dwt and have sufficient electrical power; the compact tunnel eases installation on new builds or retrofits. Avoid if you require 360° thrust vectoring, have very limited hull space for a tunnel, or need built‑in redundancy for critical maneuvering.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
TM-TT-250 bow
unverified
· 250.0 kW
· tunnel thruster
Power (kW)
250
Thrust (kN)
30.0
Diameter (mm)
700
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- 30 kN thrust output at 250 kW provides a high thrust‑to‑power ratio
- 700 mm tunnel diameter offers a relatively compact installation footprint for its power class
- Robust tunnel construction is tolerant of marine fouling and cavitation
Weaknesses
- Maximum thrust may be insufficient for very large vessels or extreme wind‑wave conditions
- Tunnel size can limit retrofit options on ships with narrow hull sections
- No publicly verified certification data (IMO D‑2, USCG, etc.) is available for this specific model
Decision Guide: Choose if the vessel needs up to 30 kN of bow thrust and has sufficient hull space for a 700 mm tunnel; avoid if higher thrust levels, tighter hull constraints, or documented class approvals are required.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
TM-TT-250 stern
unverified
· 250.0 kW
· tunnel thruster
Power (kW)
250
Thrust (kN)
30.0
Diameter (mm)
700
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust-to-power ratio (30 kN at 250 kW) for its size
- Compact 700 mm tunnel fits within standard hull openings, minimizing structural impact
- Dedicated stern installation improves aft maneuverability and reduces propeller wash interference
- Electric drive offers precise speed control and low acoustic signature
Weaknesses
- Maximum thrust may be insufficient for large vessels or heavy‑weather dynamic positioning (>50 kN required)
- Tunnel geometry can be prone to cavitation in shallow water or high‑speed flow conditions
- Installation requires significant hull penetration and reinforcement, increasing dock‑time and cost
- Limited azimuth capability compared with rotating pod thrusters for 360° thrust vectoring
Typical Vessels:
Offshore Supply Vessel (OSV)Coastal TankerFerryContainer FeederSmall Bulk Carrier
Decision Guide: Choose if you need a cost‑effective, medium‑power stern thruster for vessels up to ~30 kN thrust where hull space is limited and precise low‑speed control is required. Avoid if the vessel demands higher thrust levels, operates frequently in shallow or high‑cavitation environments, or would benefit more from 360° azimuth thrusting.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
TM-TT-300 bow
unverified
· 300.0 kW
· tunnel thruster
Power (kW)
300
Thrust (kN)
36.0
Diameter (mm)
740
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (36 kN) relative to power rating, improving manoeuvrability in tight ports
- Robust tunnel housing suitable for harsh marine environments
- Standardized bow‑mount design simplifies integration on new builds and retrofits
- Compatible with most commercial thruster control systems
Weaknesses
- Large hull penetration (740 mm diameter) limits installation to vessels with sufficient bow space
- Higher power consumption compared with smaller or azimuth thrusters of similar thrust
- Requires regular bearing lubrication and periodic inspection of the tunnel liner
- Installation cost can be significant due to structural modifications
Typical Vessels:
Offshore supply vesselCruise shipContainer ship (mid‑size)Bulk carrier (up to ~30 000 gt)LNG/LPG carrier (medium size)
Decision Guide: Choose if the vessel needs reliable, high‑thrust bow assistance for docking, low‑speed manoeuvring or dynamic positioning and has sufficient bow volume for a 740 mm tunnel. Avoid if hull space is constrained, power budget is limited, or a more compact azimuth thruster would meet performance requirements.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
TM-TT-300 stern
unverified
· 300.0 kW
· Tunnel thruster
Power (kW)
300
Thrust (kN)
36.0
Diameter (mm)
740
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (36 kN) for a relatively compact 740 mm duct diameter
- Direct integration into the hull stern section simplifies installation on new builds or retrofits
- Robust tunnel design provides good protection against debris and grounding impacts
- Suitable power rating (300 kW) matches many medium‑size vessel propulsion systems
Weaknesses
- Relatively high electrical power demand compared with smaller thrusters
- Effectiveness can be reduced in heavy sea states or strong currents
- Requires regular duct cleaning to maintain performance and avoid cavitation
- Noise and vibration levels may need mitigation on passenger‑oriented vessels
Typical Vessels:
General cargo shipsContainer feeders (up to ~150 m LOA)Bulk carriers (up to ~30,000 dwt)Offshore supply vessels
Decision Guide: Choose if: you need a high‑thrust stern thruster for medium‑size ships where space is limited and a robust ducted design is preferred. Avoid if: the vessel exceeds 30,000 dwt, operates primarily in heavy seas, or requires azimuth/omnidirectional thrust capability.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
TM-TT-400 bow
unverified
· 400.0 kW
· tunnel thruster
Power (kW)
400
Thrust (kN)
48.0
Diameter (mm)
820
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (48 kN at 400 kW) gives strong manoeuvring force.
- Large 820 mm tunnel diameter provides good water flow and reduced cavitation risk compared with smaller units.
- Compact bow installation minimizes impact on vessel draft while delivering effective side thrust.
- Integrated control interface compatible with most bridge navigation systems.
- Robust construction suited for continuous low‑speed operation in harsh port environments.
Weaknesses
- Requires a sizable hull opening (≈820 mm) which may limit retrofit options on smaller vessels.
- 400 kW power demand can strain vessel electrical distribution if not already provisioned.
- Tunnel geometry can be prone to fouling and requires regular inspection of the duct lining.
- Potential for cavitation at high RPMs, especially in shallow water or low‑speed conditions.
- Maintenance typically needs dry‑docking or specialized access ports.
Typical Vessels:
Offshore Supply VesselFerryMid‑size Container Ship (up to ~150 m LOA)Cruise Ship (smaller classes)LNG Carrier (mid‑size)
Decision Guide: Choose if the vessel needs strong bow thrust for tight berthing, has sufficient hull space for an 820 mm tunnel and can supply ~400 kW of power. Avoid on small craft with limited power budgets or where azimuth thrusters offer superior all‑direction control.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
TM-TT-400 stern
unverified
· 400.0 kW
· tunnel thruster
Power (kW)
400
Thrust (kN)
48.0
Diameter (mm)
820
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (48 kN) suitable for medium‑to‑large ships' stern manoeuvring
- Compact 820 mm tunnel diameter fits within standard hull openings
- Robust, low‑maintenance brushless motor rated at 400 kW
- Integrated control interface compatible with most bridge navigation systems
- Proven design for reliable operation in harsh marine environments
Weaknesses
- Relatively high power consumption compared with smaller thrusters
- Fixed‑direction thrust; not as versatile as azimuth or pod units
- Installation requires precise hull penetration and structural reinforcement
- Potential cavitation at very high RPMs, especially in shallow water
- Limited to vessels that can accommodate an 820 mm tunnel diameter
Typical Vessels:
Container shipBulk carrierProduct tankerCruise liner (mid‑size)Offshore supply vessel
Decision Guide: Choose if you need a high‑power, reliable stern thruster for vessels above ~30 000 DWT that can accommodate an 820 mm tunnel and have sufficient electrical generation capacity. Avoid if the ship requires omnidirectional thrust, has strict weight or space constraints, or operates primarily in very shallow waters where cavitation risk is critical.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
TM-TT-500 bow
unverified
· 500.0 kW
· tunnel bow thruster
Power (kW)
500
Thrust (kN)
60.0
Diameter (mm)
900
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (60 kN) relative to its power rating (500 kW)
- Large 900 mm tunnel diameter gives efficient water flow and reduced cavitation
- Compact installation footprint compared with external azimuth pods
- Designed for bow placement, improving docking and low‑speed handling
Weaknesses
- Requires a sizable hull opening (≈0.9 m) limiting retrofit options on smaller vessels
- Power demand of 500 kW can strain vessel electrical systems if not sized appropriately
- Tunnel lining wear may increase maintenance intervals in high‑usage ports
- Limited to vessels that can accommodate the duct length and structural reinforcement
Typical Vessels:
Offshore supply vesselCruise ship (mid‑size)Container feederGeneral cargo / bulk carrier up to ~30 000 DWT
Decision Guide: Choose if the vessel needs strong low‑speed maneuverability in confined ports, has sufficient hull space for a 0.9 m tunnel, and can supply 500 kW electrical power. Avoid if hull modifications are prohibitive, budget is tight, or the vessel operates primarily at open sea where bow thrusters add little value.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
TM-TT-500 stern
unverified
· 500.0 kW
· tunnel thruster
Power (kW)
500
Thrust (kN)
60.0
Diameter (mm)
900
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (60 kN) relative to power rating, giving strong low‑speed manoeuvring capability
- Relatively compact installation footprint for a 500 kW unit, fitting into standard stern tunnel sections
- All‑electric drive eliminates the need for hydraulic systems and associated maintenance
- Designed for stern mounting, improving aft handling during docking and emergency stops
Weaknesses
- High electrical power demand (500 kW) may require upgrades to vessel power distribution
- Large tunnel diameter (900 mm) can limit placement on vessels with restricted hull space
- Installation requires significant hull penetration and structural reinforcement
- No publicly confirmed certifications or class approvals, requiring verification before installation
Typical Vessels:
Container shipBulk carrierRo‑Ro vesselOffshore supply vesselCruise liner (larger units)
Decision Guide: Choose if: you need a high‑thrust, all‑electric stern thruster for vessels of 30 000 gt and above where hull space allows a 900 mm tunnel and the ship’s power plant can supply ~500 kW. Avoid if: vessel electrical capacity is limited, hull geometry restricts large tunnel diameters, or class societies require documented certifications that are not yet confirmed for this model.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
TM-TT-600 bow
unverified
· 600.0 kW
· tunnel thruster
Power (kW)
600
Thrust (kN)
72.0
Diameter (mm)
980
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (72 kN) for its power rating, improving manoeuvring capability
- Large 980 mm tunnel diameter reduces cavitation risk and increases efficiency
- Bow placement provides direct control during docking and low‑speed operations
Weaknesses
- Requires significant bow space to accommodate the ~1 m duct diameter
- High power demand (600 kW) may increase fuel consumption when used frequently
- Installation and maintenance can be more complex on vessels with limited hull access
Typical Vessels:
Cruise shipLNG carrierOffshore support vesselContainer shipTanker
Decision Guide: Choose if the vessel needs high bow‑thruster thrust for precise docking or DP assistance and has sufficient hull space for a ~1 m tunnel. Avoid if bow geometry is constrained, power budget is limited, or a smaller thruster would meet manoeuvring requirements.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
TM-TT-600 stern
unverified
· 600.0 kW
· tunnel thruster
Power (kW)
600
Thrust (kN)
72.0
Diameter (mm)
980
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (72 kN) suitable for large ships and tight berths
- Large 980 mm tunnel diameter provides efficient water flow and reduced cavitation risk at rated power
- 600 kW motor offers rapid response for dynamic positioning or emergency maneuvers
- Stern mounting improves aft steering control, especially on vessels with limited bow thruster space
Weaknesses
- Physical size requires substantial hull cut‑out; may be difficult to retrofit on smaller ships
- High power rating leads to increased fuel consumption and electrical load
- Maintenance of the large tunnel bearing and seals can be more demanding than smaller units
- Installation cost is higher than lower‑power thruster alternatives
Typical Vessels:
Container shipBulk carrierCruise linerLNG/LPG carrierOffshore support vessel
Decision Guide: Choose if the vessel needs a high‑thrust stern thruster for precise aft maneuvering, dynamic positioning, or to complement an existing bow thruster on large ships. Avoid if hull space is limited, the vessel’s displacement does not justify a 600 kW unit, or budget constraints favor a lower‑power solution.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
TM-TT-750 bow
unverified
· 750.0 kW
· tunnel thruster
Power (kW)
750
Thrust (kN)
90.0
Diameter (mm)
1100
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (90 kN) for its size, enabling effective bow control on large ships
- Robust tunnel construction reduces blade wear and simplifies maintenance
- Integrated hydraulic drive rated at 750 kW provides reliable power in demanding conditions
- Standard 1.1 m tunnel diameter fits common hull openings for new‑build installations
Weaknesses
- High power demand (750 kW) increases vessel fuel consumption when used frequently
- Large tunnel aperture requires significant hull penetration and structural reinforcement
- Potential cavitation at high RPMs may limit efficiency in shallow water
- Limited field data on long‑term reliability for this specific model
Typical Vessels:
Cruise shipContainer vessel (≥8,000 TEU)LNG carrierOffshore supply vesselLarge bulk carrier
Decision Guide: Choose if: you need a bow thruster with >90 kN thrust for vessels larger than 150 m LOA and have sufficient power generation capacity. Avoid if: the ship has strict weight or space constraints, operates primarily in shallow waters where cavitation risk is high, or budget limits preclude a 750 kW hydraulic drive.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
TM-TT-750 stern
unverified
· 750.0 kW
· Tunnel thruster
Power (kW)
750
Thrust (kN)
90.0
Diameter (mm)
1100
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (90 kN) suitable for berthing and unberthing of large ships
- Compact tunnel arrangement fits within a 1.1 m hull opening, minimizing structural intrusion
- Direct‑drive motor design reduces moving parts and maintenance intervals
- Optimised stern flow geometry improves efficiency during reverse thrust
Weaknesses
- Large 1100 mm diameter requires substantial hull modification on smaller vessels
- 750 kW power demand can increase auxiliary fuel consumption when used frequently
- Potential for cavitation if installed in high‑speed water flow without proper sizing
- No publicly verified IMO or classification society approvals identified
Typical Vessels:
Crude oil tankerContainer ship (≥8,000 TEU)Cruise linerOffshore supply vesselLarge bulk carrier
Decision Guide: Choose if the vessel needs high‑thrust stern maneuvering capability and can accommodate a 1.1 m tunnel opening; avoid if hull space is limited, power budget is tight, or verified classification approvals are required.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
TM-TT-800 bow
unverified
· 800.0 kW
· High-power tunnel thruster
Power (kW)
800
Thrust (kN)
96.0
Diameter (mm)
1140
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (96 kN) suitable for large vessels and tight port manoeuvring
- Robust 800 kW electric drive provides strong, reliable power output
- Compact tunnel geometry fits within standard hull sections without excessive external protrusion
- No recorded failure history in the reference catalog, indicating baseline reliability
Weaknesses
- Large tunnel diameter (1.14 m) may require significant hull penetration and structural reinforcement
- High power rating leads to greater electrical load and operating cost
- Manufacturer not widely represented in global certification registers, which can affect class approvals
- Limited aftermarket support and spare‑part availability compared with major thruster brands
Typical Vessels:
Container shipBulk carrierTankerCruise linerOffshore supply vessel
Decision Guide: Choose if: you need maximum bow thrust for vessels >30 000 GT operating in confined ports or requiring dynamic positioning support, and hull space can accommodate a 1.14 m tunnel. Avoid if: class societies demand specific type approvals that the model lacks, electrical generation capacity is limited, or budget constraints favour smaller, lower‑cost thrusters.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
TM-TT-800 stern
unverified
· 800.0 kW
· tunnel thruster
Power (kW)
800
Thrust (kN)
96.0
Diameter (mm)
1140
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (96 kN) relative to power rating (800 kW)
- Compact tunnel layout fits within hull without protruding appendages
- Integrated water‑flow cooling system for continuous operation
- Suitable for dynamic positioning and tight‑berth maneuvers
Weaknesses
- Large tunnel diameter (1.14 m) may limit installation in vessels with restricted hull space
- High electrical power demand (800 kW) requires robust shipboard supply
- Limited publicly available data on spare‑parts availability and service network
- No confirmed class or regulatory certifications
Typical Vessels:
Offshore Supply VesselCruise ShipLarge Bulk CarrierLNG/LPG Carrier
Decision Guide: Choose if: you need a high‑thrust stern thruster for large vessels with sufficient hull space and robust power supply, especially when dynamic positioning or tight‑berth handling is required. Avoid if: vessel size or hull geometry cannot accommodate a 1.14 m tunnel, or lower thrust/power solutions would meet the maneuvering needs.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
TM-TT-1000 bow
unverified
· 1000.0 kW
· high‑power tunnel thruster
Power (kW)
1000
Thrust (kN)
120.0
Diameter (mm)
1300
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (120 kN) suitable for large ships and DP assistance
- Robust tunnel design reduces cavitation and improves durability
- Large 1300 mm diameter provides ample flow for efficient thrust generation
- Integrated bow mounting simplifies installation on new builds
Weaknesses
- Large physical size limits fitment in vessels with narrow hull sections
- High power rating (1000 kW) leads to significant electrical demand and cooling requirements
- Installation may require reinforcement of the hull structure
- Potentially longer lead‑time for spare parts if Thrustmaster Marine has limited global service network
Typical Vessels:
Cruise shipOffshore supply vesselHeavy lift vesselLarge container shipRo‑Ro ferry
Decision Guide: Choose if the vessel needs >100 kN of bow thrust for tight port manoeuvring, dynamic positioning or high‑speed docking and has sufficient hull space and power supply. Avoid if the ship’s design constraints limit tunnel diameter, or if a lower‑power thruster would meet the operational requirements more economically.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
TM-TT-1000 stern
unverified
· 1000.0 kW
· tunnel thruster
Power (kW)
1000
Thrust (kN)
120.0
Diameter (mm)
1300
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (120 kN) suitable for maneuvering large ships or DP‑required vessels
- Large 1300 mm tunnel allows efficient water flow, reducing cavitation risk
- Integrated control system compatible with most bridge consoles
- Robust construction typical of Thrustmaster Marine products, aimed at heavy‑duty service
Weaknesses
- High power demand (1 MW) requires substantial electrical supply and cooling capacity
- Large hull penetration may limit installation on vessels with restricted stern space
- Installation and alignment are complex, increasing dockyard time and cost
- Potentially higher maintenance due to size of rotating components
Typical Vessels:
Crude oil tankerLNG carrierCruise shipOffshore supply vesselLarge container vessel
Decision Guide: Choose if the vessel needs very high lateral thrust for safe port entry, dynamic positioning or emergency maneuvering and has sufficient power and space for a 1.3 m stern tunnel. Avoid if the ship’s electrical system cannot support ~1 MW thruster loads, or if hull geometry restricts large tunnel installations.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
TM-TT-1200 bow
unverified
· 1200.0 kW
· high‑power tunnel thruster
Power (kW)
1200
Thrust (kN)
144.0
Diameter (mm)
1460
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust output (144 kN) suitable for large ships and DP operations
- Large 1.46 m duct diameter reduces cavitation and improves hydraulic efficiency
- Robust tunnel construction designed for heavy-duty marine environments
- Compact bow‑mount footprint relative to its power rating
- Modular design facilitates routine inspection and component replacement
Weaknesses
- High power demand (1.2 MW) increases vessel fuel consumption and requires substantial electrical/hydraulic supply
- Large duct size can limit installation in vessels with restricted bow space
- Installation and commissioning require significant engineering effort and integration time
- Maintenance of large‑diameter bearings and seals may be more complex than smaller units
Typical Vessels:
Crude oil tankerContainer shipBulk carrierLNG/LPG carrierCruise shipOffshore supply vesselDP‑class platform support vessel
Decision Guide: Choose if the vessel requires high bow thrust for safe port entry, dynamic positioning or emergency maneuvering and has sufficient power and space allocation. Avoid if the ship is small, has tight bow geometry, or seeks a low‑power thruster solution.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
TM-TT-1200 stern
unverified
· 1200.0 kW
· tunnel thruster
Power (kW)
1200
Thrust (kN)
144.0
Diameter (mm)
1460
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (144 kN) suitable for large ships and dynamic positioning
- Compact tunnel footprint compared with equivalent azimuth units, preserving hull form
- Robust stainless‑steel construction typical of Thrustmaster Marine for long service life
- Integrated control electronics compatible with most bridge navigation systems
Weaknesses
- Large 1.46 m tunnel diameter requires significant stern space and structural reinforcement
- High power demand (1 200 kW) increases vessel electrical load and fuel consumption when driven hydraulically
- Potential for cavitation at high RPMs, especially in shallow water operations
- Higher upfront cost than smaller‑capacity thrusters
Typical Vessels:
Cruise shipLNG carrierOffshore supply vesselContainer ship (large class)Bulk carrier (≥150 kt)
Decision Guide: Choose if the vessel needs very high stern thrust for DP or tight‑port manoeuvring and has sufficient stern volume to accommodate a 1.46 m tunnel. Avoid on shallow‑draft ships, vessels with limited stern space, or when lower power/cost solutions are adequate.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
TM-TT-1500 bow
unverified
· 1500.0 kW
· tunnel thruster
Power (kW)
1500
Thrust (kN)
180.0
Diameter (mm)
1700
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (180 kN) suitable for ultra‑large ships and tight berthing situations
- Large 1.7 m tunnel diameter provides efficient water flow and reduced cavitation risk
- 1500 kW motor offers rapid response for dynamic positioning or emergency maneuvers
- Bow location improves overall vessel handling when combined with a stern thruster
Weaknesses
- Significant space requirement in the hull due to 1.7 m tunnel diameter
- High power consumption (1500 kW) increases fuel/energy costs and may need upgraded electrical supply
- Installation complexity and cost are higher than smaller, low‑power units
- Potential for increased vibration and noise if not properly isolated
Typical Vessels:
Ultra‑large Container ShipVery Large Crude Carrier (VLCC)LNG CarrierBulk Carrier (>200 kt)Offshore Support Vessel
Decision Guide: Choose if: you need maximum bow thrust for vessels >150 m LOA, dynamic positioning, or restricted port manoeuvring. Avoid if: hull space is limited, vessel power budget is low, or a smaller thruster meets the maneuverability requirements.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
TM-TT-1500 stern
unverified
· 1500.0 kW
· tunnel thruster
Power (kW)
1500
Thrust (kN)
180.0
Diameter (mm)
1700
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust output (180 kN) suitable for large ships and DP operations
- Large 1700 mm duct provides efficient water flow and reduced hydraulic losses
- Designed for 1500 kW power, compatible with modern high‑capacity electric drives
- Robust construction from Thrustmaster Marine, a recognised supplier of marine propulsion equipment
- Improves stern maneuverability during docking, undocking and low‑speed maneuvers
Weaknesses
- Physical size requires substantial hull penetration and structural reinforcement
- High electrical power demand (1.5 MW) may strain vessel power generation capacity
- Tunnel geometry can be less efficient than azimuth pods at very low speeds
- Risk of cavitation if installed in shallow draft or without proper flow optimisation
- Maintenance access can be limited due to stern location and duct size
Typical Vessels:
Very Large Crude Carrier (VLCC)Ultra‑Large Container Vessel (ULCV)Panamax Bulk CarrierCruise ShipOffshore Supply Vessel
Decision Guide: Choose if the vessel requires high stern thrust for dynamic positioning, tight port manoeuvring or emergency backup on large tonnage ships and has sufficient electrical generation capacity. Avoid if hull space is limited, power plant cannot support a 1.5 MW load, or if a more compact azimuth thruster would meet the maneuverability requirements.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
TM-TT-2000 bow
unverified
· 2000.0 kW
· high‑power tunnel thruster
Power (kW)
2000
Thrust (kN)
240.0
Diameter (mm)
2100
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (240 kN) suitable for ships >150 m LOA
- Compact tunnel diameter relative to thrust output reduces hull penetration size
- Integrated variable‑frequency drive allows fine speed control
- Robust steel housing designed for harsh marine environments
Weaknesses
- High electrical power demand (≈2 MW) requires substantial onboard generation capacity
- Large installation footprint and deep tunnel may limit retrofit options on smaller hulls
- Maintenance of large‑diameter bearings and seals can be intensive
- Potential for cavitation at full load if not matched with proper propeller design
Typical Vessels:
Cruise shipLNG carrierContainer vesselBulk carrierOffshore supply vessel
Decision Guide: Choose if: you need maximum bow thrust for a large vessel, have sufficient power generation capacity, and can accommodate a 2.1 m tunnel diameter. Avoid if: the ship has limited hull space, power plant cannot support ~2 MW thruster load, or lower‑cost/lower‑power solutions meet maneuverability needs.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
TM-TT-2000 stern
unverified
· 2000.0 kW
· high‑power tunnel thruster
Power (kW)
2000
Thrust (kN)
240.0
Diameter (mm)
2100
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (240 kN) suitable for large ships and DP operations
- Compact tunnel footprint compared with equivalent azimuth units
- Robust stainless‑steel housing designed for harsh marine environments
- Integrated control electronics compatible with most bridge systems
Weaknesses
- High power demand (2 000 kW) increases fuel consumption when used frequently
- Large diameter (2.1 m) may limit installation in vessels with restricted hull space
- Potential for cavitation at low forward speeds if not properly sized to the vessel
- Less directional flexibility than a 360° azimuth thruster
Typical Vessels:
Cruise shipLNG carrierVery Large Crude Carrier (VLCC)Offshore supply vesselContainer ship (large class)
Decision Guide: Choose if you need a high‑thrust, space‑efficient stern thruster for large vessels that already have tunnel installations and can accommodate the power load. Avoid if you require full 360° thrust vectoring, operate in very shallow draft conditions, or want lower power consumption for frequent use.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
TM-TT-2500 bow
unverified
· 2500.0 kW
· tunnel thruster
Power (kW)
2500
Thrust (kN)
300.0
Diameter (mm)
2500
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (300 kN) suitable for large ships and tight port maneuvers
- Large 2.5 m tunnel diameter provides efficient water flow and reduced cavitation risk at design speed
- 2500 kW motor offers rapid response for dynamic positioning or emergency maneuvering
- Bow‑mount location improves turning radius and reduces reliance on rudder authority
Weaknesses
- Large physical size limits installation to vessels with sufficient hull volume in the bow section
- High power rating results in greater electrical load and may require upgraded shipboard power distribution
- Potential for increased noise and vibration compared with smaller thrusters
- Installation and maintenance costs are higher due to size and motor rating
Typical Vessels:
Very Large Crude Carrier (VLCC)Ultra‑Large Container Vessel (ULCV)Cruise ShipOffshore Supply Vessel (OSV)Heavy Lift / Ro‑Ro vessel
Decision Guide: Choose if the ship needs maximum bow thrust for safe docking, dynamic positioning or emergency maneuvering and has sufficient hull space and power capacity. Avoid if the vessel is size‑restricted, has limited electrical generation capability, or if a lower‑cost, smaller thruster would meet the maneuverability requirements.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
TM-TT-2500 stern
unverified
· 2500.0 kW
· electric tunnel thruster
Power (kW)
2500
Thrust (kN)
300.0
Diameter (mm)
2500
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (≈300 kN) suitable for large vessels and DP operations
- Large 2500 mm tunnel provides efficient water flow and reduced cavitation risk
- Electric drive offers low vibration, quick response and easier integration with ship power systems
- Designed for continuous duty with robust bearing and seal packages
Weaknesses
- Physical size limits installation to vessels with ample stern space
- High electrical power demand (≈2.5 MW) may require significant generator capacity
- Capital cost is high compared with smaller hydraulic units
- Maintenance of large‑diameter tunnel and bearings can be more intensive
Typical Vessels:
VLCCULCVLarge LNG carrierCruise shipOffshore support vessel (DP class)
Decision Guide: Choose if you need high‑thrust, low‑speed maneuverability on a large DP‑class vessel and have sufficient electrical generation capacity. Avoid if the vessel is size‑restricted, budget‑constrained, or prefers hydraulic thrusters for simplicity.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
TM-TT-3000 bow
unverified
· 3000.0 kW
· tunnel thruster
Power (kW)
3000
Thrust (kN)
360.0
Diameter (mm)
2900
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (360 kN) suitable for large ships and DP operations
- Large 2.9 m duct diameter reduces cavitation risk at high power levels
- Direct integration with ship control systems for precise maneuvering
- Robust construction typical of 3000 kW marine thrusters
Weaknesses
- High electrical power demand (3 MW) increases fuel‑to‑electric load and operating cost
- Large physical size requires substantial hull penetration and space
- Installation and maintenance are more complex than smaller units
- Potential for higher acoustic noise and vibration at full power
Typical Vessels:
Very Large Crude Carrier (VLCC)LNG carrierCruise shipOffshore supply vesselLarge container vessel
Decision Guide: Choose if: you need maximum bow thrust for vessels >150 m LOA, DP‑class or tight‑port maneuvering, and have sufficient power generation capacity. Avoid if: hull space is limited, budget constraints restrict high‑power electric systems, or the vessel’s maneuverability requirements are modest.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
TM-TT-3000 stern
unverified
· 3000.0 kW
· High‑power tunnel thruster
Power (kW)
3000
Thrust (kN)
360.0
Diameter (mm)
2900
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (360 kN) enables rapid sideways movement for mega‑vessels during docking and low‑speed maneuvers.
- Large 2.9 m tunnel diameter reduces cavitation risk at full power, improving efficiency and blade life.
- Integrated control system compatible with most bridge navigation suites for precise thrust vectoring.
- Designed for stern installation on vessels requiring strong aft maneuverability (e.g., cruise ships, LNG carriers).
Weaknesses
- 3 MW electric drive demands substantial onboard power generation capacity and may increase fuel consumption.
- Physical size and weight require extensive hull reinforcement and complex installation procedures.
- Higher initial capital cost compared with lower‑power thrusters or azimuth pods of similar thrust.
- Maintenance of large bearings, seals and cooling system can be more intensive than smaller units.
Typical Vessels:
Cruise shipLNG carrierVLCC / ULCC tankerLarge container vesselOffshore supply vessel (OSV) with high‑power maneuvering needs
Decision Guide: Choose if: you need >300 kN of stern thrust on a vessel larger than 150 m LOA, have sufficient onboard power generation, and require precise low‑speed handling (e.g., tight berths, offshore rigs). Avoid if: the ship’s power plant cannot support an extra 3 MW load, hull space is limited, or budget constraints favor lower‑power solutions.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
TM-TT-3500 bow
unverified
· 3500.0 kW
Power (kW)
3500
Thrust (kN)
420.0
Diameter (mm)
3300
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust output (≈420 kN) suitable for precise positioning of large ships
- Compact tunnel design compared with external azimuth units, saving deck space
- Integrated power rating (3.5 MW) allows direct coupling to ship’s main electric distribution
- Large diameter provides efficient water flow and reduced cavitation risk
Weaknesses
- High electrical power demand may require substantial generator capacity
- Diameter of 3.3 m can limit installation in vessels with narrow hull sections or restrict aft placement
- Tunnel geometry makes routine inspection and maintenance more labour‑intensive than open‑propeller units
- Potential for increased vibration and noise if not properly isolated
Typical Vessels:
Cruise shipsVery large container vesselsOffshore supply & anchor handling tug supply (AHTS) vesselsHeavy lift / Ro‑Ro ferries
Decision Guide: Choose if: you need a bow thruster with very high thrust for a vessel >150 m LOA, have sufficient onboard power generation, and can accommodate a 3.3 m tunnel diameter. Avoid if: the hull form or available space cannot house a large tunnel unit, or the ship’s power plant is limited to lower electrical loads.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
TM-TT-3500 stern
unverified
· 3500.0 kW
· hydraulic-driven tunnel thruster
Power (kW)
3500
Thrust (kN)
420.0
Diameter (mm)
3300
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high static thrust (420 kN) suitable for mega‑size tankers and cruise ships
- Robust sealed tunnel housing minimizes cavitation and corrosion risk
- Integrated hydraulic drive reduces installation footprint compared to electric drives
- Low vibration and noise due to balanced rotor design
- Optional remote monitoring interface for condition based maintenance
Weaknesses
- Large 3.3 m tunnel requires extensive hull penetration and structural reinforcement
- High power demand (3 500 kW) increases fuel consumption when operated frequently
- Installation is complex and may extend shipbuilding schedule
- Less flexible than azimuth thrusters for dynamic positioning maneuvers
- Long lead‑time for custom fabrication of the oversized tunnel
Typical Vessels:
VLCCULCCLarge container ships (>10 000 TEU)Cruise linersOffshore supply vessels (large class)
Decision Guide: Choose if the vessel requires very high static thrust for berthing or un‑berthing in confined ports and space for a large tunnel is available. Avoid if the ship size is moderate, if dynamic positioning with 360° thrust is needed, or if weight/installation constraints make a smaller azimuth unit more practical.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
TM-TT-4000 bow
unverified
· 4000.0 kW
· tunnel thruster
Power (kW)
4000
Thrust (kN)
480.0
Diameter (mm)
3700
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high power rating (4 MW) provides strong thrust for precise handling of mega‑vessels.
- Large 3.7 m tunnel diameter reduces cavitation and improves hydraulic efficiency.
- Single‑unit design simplifies installation compared with multiple smaller units.
Weaknesses
- High electrical/hydraulic power demand may exceed the capacity of older ship service systems.
- The physical size of the duct requires substantial hull penetration space, limiting use on vessels with restricted bow geometry.
- Potentially higher initial cost and longer lead‑time for a bespoke high‑thrust unit.
Typical Vessels:
Cruise shipsLNG carriersVery large crude carriers (VLCC)Offshore supply vesselsMega container ships
Decision Guide: Choose if the vessel needs a single, high‑thrust bow thruster for dynamic positioning or tight berth handling and has sufficient power generation capacity. Avoid if space in the bow is limited, the ship’s service power plant cannot support a 4 MW unit, or a lower‑cost, lower‑power solution would meet maneuverability requirements.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
TM-TT-4000 stern
unverified
· 4000.0 kW
Power (kW)
4000
Thrust (kN)
480.0
Diameter (mm)
3700
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (480 kN) suitable for large tankers, container ships and offshore vessels
- Large tunnel diameter (3.7 m) provides efficient water flow and reduced cavitation
- Compact stern installation frees deck space compared with external azimuth thrusters
- Integrated control interface compatible with most ship bridge systems
Weaknesses
- High power rating (4 MW) leads to significant electrical demand and associated cabling costs
- Large physical size may limit retro‑fit options on vessels with restricted hull space
- Tunnel design can be prone to debris ingress if not regularly inspected
- Potentially higher initial cost than smaller, lower‑thrust tunnel units
Typical Vessels:
Crude oil tankerLiquefied gas carrierLarge container shipBulk carrier (>150 kt)Offshore supply vessel with DP capability
Decision Guide: Choose if the vessel requires very high stern thrust for safe docking, dynamic positioning or emergency maneuvering of a large displacement hull. Avoid if the ship is small‑to‑medium size where the power and size of the TM‑TT‑4000 would be excessive and increase capital and operating costs unnecessarily.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
TM-TT-4500 bow
unverified
· 4500.0 kW
· tunnel thruster
Power (kW)
4500
Thrust (kN)
540.0
Diameter (mm)
4100
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust output (540 kN) enables rapid lateral movement for very large ships.
- High power rating (4.5 MW) provides strong control even in adverse wind and sea conditions.
- Large tunnel diameter (4.1 m) promotes efficient water flow and reduces cavitation risk.
- Bow‑mounting design integrates with hull structure for optimal thrust vector.
Weaknesses
- Large physical size requires extensive hull penetration, limiting retrofit options.
- High electrical power demand necessitates robust shipboard power generation and distribution.
- Installation and maintenance are more complex due to the sizable tunnel housing.
- Potentially higher initial cost and longer lead time compared with smaller thrusters.
Decision Guide: Choose if you need a bow thruster capable of delivering >500 kN thrust for very large vessels, operating in ports with strong currents or winds, or supporting dynamic positioning. Avoid if vessel size, power plant capacity, or hull space cannot accommodate the 4.1 m tunnel diameter and 4.5 MW electrical load.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
TM-TT-4500 stern
unverified
· 4500.0 kW
· tunnel thruster
Power (kW)
4500
Thrust (kN)
540.0
Diameter (mm)
4100
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (≈540 kN) suitable for VLCCs, LNG carriers and cruise ships
- Robust tunnel construction provides good protection against debris and grounding impacts
- Integrated control interface compatible with most ship‑handling automation systems
- Large 4.1 m duct diameter gives efficient water flow and reduced cavitation at high power
Weaknesses
- High electrical demand (≈4.5 MW) requires substantial onboard power generation capacity
- Large physical envelope limits installation to vessels with ample stern space
- Potentially higher acquisition and lifecycle cost compared with lower‑power alternatives
- Spare‑part availability may be limited if Thrustmaster Marine has a small dealer network
Typical Vessels:
Very Large Crude Carrier (VLCC)LNG carrierCruise shipOffshore supply vesselLarge container vessel
Decision Guide: Choose if: you need >500 kN of stern thrust for a vessel over 200 m LOA, have sufficient power generation and hull space, and require reliable low‑speed manoeuvring or DP support. Avoid if: the ship is smaller, power budget is limited, or installation space at the stern is constrained.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
TM-TT-5000 bow
unverified
· 5000.0 kW
· tunnel thruster
Power (kW)
5000
Thrust (kN)
600.0
Diameter (mm)
4500
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust output (≈600 kN) suitable for mega‑vessels
- Large tunnel diameter reduces cavitation and improves efficiency
- Integrated control interface compatible with common bridge systems
- Robust, sealed design minimizes maintenance in harsh marine environments
Weaknesses
- Significant hull penetration (4.5 m) complicates installation and structural reinforcement
- High power demand (≈5 MW) requires substantial onboard electrical generation capacity
- Large physical size limits retro‑fit options on smaller ships
- Potentially higher initial cost and longer lead time compared with lower‑power alternatives
Typical Vessels:
Very Large Crude Carrier (VLCC)Ultra Large Container Ship (ULCS)Bulk carrier >200 ktOffshore supply vessel (large class)
Decision Guide: Choose if: the vessel exceeds 150 kt deadweight and requires strong bow thrust for port entry, dynamic positioning or tight maneuvering; you have sufficient power generation capacity and can accommodate a large hull opening. Avoid if: the ship is smaller than 50 kt deadweight, power supply is limited, or installation space/structural constraints make a 4.5 m tunnel impractical.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
TM-TT-5000 stern
unverified
· 5000.0 kW
· tunnel thruster
Power (kW)
5000
Thrust (kN)
600.0
Diameter (mm)
4500
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust output (≈600 kN) suitable for mega‑size tankers and bulk carriers
- Large 4.5 m tunnel diameter gives excellent flow efficiency and reduced cavitation risk
- Integrated control interface compatible with most bridge navigation systems
- Robust housing designed for harsh marine environments
Weaknesses
- High installed power (≈5 MW) leads to significant fuel consumption when used frequently
- Large physical size requires substantial hull penetration and structural reinforcement
- Installation and commissioning are complex, increasing dock‑time and cost
- Limited availability of spare parts in remote ports compared with more common manufacturers
Typical Vessels:
Very Large Crude Carrier (VLCC)Ultra Large Container Vessel (ULCV)Large Bulk CarrierOffshore Supply Vessel (OSV) – heavy‑lift variant
Decision Guide: Choose if you need maximum lateral thrust for a vessel over 200 m LOA operating in tight ports or offshore terminals, and you can accommodate the large tunnel opening and power demand. Avoid if vessel size, power plant capacity, or budget constraints make a smaller, lower‑power thruster more appropriate.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
30TT150ML-AL
✓ verified
Application
Electric motor-driven tunnel thruster for bow/stern docking, slow speed maneuvering, emergency steering, station keeping
Common Failures & Inspection Points
- Area: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensionsCheck: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensions
- Area: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrCheck: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrainment
- Area: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfacesCheck: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfaces
- Area: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating watersCheck: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating waters
- Area: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to cCheck: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to check due to integrated hydraulic lubrication)
- Area: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestCheck: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestion
- Area: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal areaCheck: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal area
- Area: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulatioCheck: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulation
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
30TT150ML-CS
✓ verified
Application
Electric motor-driven tunnel thruster for bow/stern docking, slow speed maneuvering, emergency steering, station keeping
Common Failures & Inspection Points
- Area: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensionsCheck: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensions
- Area: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrCheck: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrainment
- Area: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfacesCheck: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfaces
- Area: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating watersCheck: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating waters
- Area: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to cCheck: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to check due to integrated hydraulic lubrication)
- Area: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestCheck: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestion
- Area: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal areaCheck: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal area
- Area: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulatioCheck: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulation
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
30TT200ML-AL
✓ verified
Application
Electric motor-driven tunnel thruster for bow/stern docking, slow speed maneuvering, emergency steering, station keeping
Common Failures & Inspection Points
- Area: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensionsCheck: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensions
- Area: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrCheck: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrainment
- Area: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfacesCheck: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfaces
- Area: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating watersCheck: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating waters
- Area: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to cCheck: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to check due to integrated hydraulic lubrication)
- Area: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestCheck: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestion
- Area: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal areaCheck: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal area
- Area: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulatioCheck: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulation
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
30TT200ML-CS
✓ verified
Application
Electric motor-driven tunnel thruster for bow/stern docking, slow speed maneuvering, emergency steering, station keeping
Common Failures & Inspection Points
- Area: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensionsCheck: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensions
- Area: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrCheck: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrainment
- Area: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfacesCheck: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfaces
- Area: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating watersCheck: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating waters
- Area: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to cCheck: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to check due to integrated hydraulic lubrication)
- Area: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestCheck: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestion
- Area: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal areaCheck: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal area
- Area: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulatioCheck: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulation
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
36TT300ML-AL
✓ verified
Application
Electric motor-driven tunnel thruster for bow/stern docking, slow speed maneuvering, emergency steering, station keeping
Common Failures & Inspection Points
- Area: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensionsCheck: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensions
- Area: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrCheck: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrainment
- Area: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfacesCheck: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfaces
- Area: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating watersCheck: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating waters
- Area: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to cCheck: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to check due to integrated hydraulic lubrication)
- Area: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestCheck: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestion
- Area: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal areaCheck: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal area
- Area: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulatioCheck: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulation
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
36TT300ML-CS
✓ verified
Application
Electric motor-driven tunnel thruster for bow/stern docking, slow speed maneuvering, emergency steering, station keeping
Common Failures & Inspection Points
- Area: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensionsCheck: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensions
- Area: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrCheck: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrainment
- Area: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfacesCheck: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfaces
- Area: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating watersCheck: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating waters
- Area: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to cCheck: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to check due to integrated hydraulic lubrication)
- Area: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestCheck: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestion
- Area: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal areaCheck: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal area
- Area: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulatioCheck: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulation
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
42TT400ML-AL
✓ verified
Application
Electric motor-driven tunnel thruster for bow/stern docking, slow speed maneuvering, emergency steering, station keeping
Common Failures & Inspection Points
- Area: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensionsCheck: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensions
- Area: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrCheck: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrainment
- Area: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfacesCheck: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfaces
- Area: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating watersCheck: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating waters
- Area: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to cCheck: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to check due to integrated hydraulic lubrication)
- Area: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestCheck: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestion
- Area: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal areaCheck: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal area
- Area: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulatioCheck: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulation
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
42TT400ML-CS
✓ verified
Application
Electric motor-driven tunnel thruster for bow/stern docking, slow speed maneuvering, emergency steering, station keeping
Common Failures & Inspection Points
- Area: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensionsCheck: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensions
- Area: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrCheck: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrainment
- Area: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfacesCheck: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfaces
- Area: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating watersCheck: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating waters
- Area: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to cCheck: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to check due to integrated hydraulic lubrication)
- Area: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestCheck: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestion
- Area: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal areaCheck: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal area
- Area: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulatioCheck: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulation
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
47TT500ML-CS
✓ verified
Application
Electric motor-driven tunnel thruster for bow/stern docking, slow speed maneuvering, emergency steering, station keeping
Common Failures & Inspection Points
- Area: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensionsCheck: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensions
- Area: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrCheck: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrainment
- Area: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfacesCheck: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfaces
- Area: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating watersCheck: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating waters
- Area: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to cCheck: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to check due to integrated hydraulic lubrication)
- Area: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestCheck: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestion
- Area: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal areaCheck: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal area
- Area: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulatioCheck: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulation
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
52TT600ML-CS
✓ verified
Application
Electric motor-driven tunnel thruster for bow/stern docking, slow speed maneuvering, emergency steering, station keeping
Common Failures & Inspection Points
- Area: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensionsCheck: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensions
- Area: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrCheck: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrainment
- Area: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfacesCheck: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfaces
- Area: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating watersCheck: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating waters
- Area: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to cCheck: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to check due to integrated hydraulic lubrication)
- Area: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestCheck: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestion
- Area: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal areaCheck: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal area
- Area: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulatioCheck: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulation
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
56TT800ML-CS
✓ verified
Application
Electric motor-driven tunnel thruster for bow/stern docking, slow speed maneuvering, emergency steering, station keeping
Common Failures & Inspection Points
- Area: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensionsCheck: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensions
- Area: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrCheck: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrainment
- Area: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfacesCheck: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfaces
- Area: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating watersCheck: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating waters
- Area: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to cCheck: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to check due to integrated hydraulic lubrication)
- Area: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestCheck: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestion
- Area: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal areaCheck: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal area
- Area: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulatioCheck: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulation
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
66TT1000ML-CS
✓ verified
Application
Electric motor-driven tunnel thruster for bow/stern docking, slow speed maneuvering, emergency steering, station keeping
Common Failures & Inspection Points
- Area: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensionsCheck: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensions
- Area: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrCheck: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrainment
- Area: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfacesCheck: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfaces
- Area: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating watersCheck: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating waters
- Area: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to cCheck: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to check due to integrated hydraulic lubrication)
- Area: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestCheck: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestion
- Area: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal areaCheck: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal area
- Area: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulatioCheck: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulation
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
72TT1250ML-CS
✓ verified
Application
Electric motor-driven tunnel thruster for bow/stern docking, slow speed maneuvering, emergency steering, station keeping
Common Failures & Inspection Points
- Area: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensionsCheck: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensions
- Area: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrCheck: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrainment
- Area: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfacesCheck: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfaces
- Area: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating watersCheck: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating waters
- Area: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to cCheck: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to check due to integrated hydraulic lubrication)
- Area: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestCheck: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestion
- Area: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal areaCheck: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal area
- Area: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulatioCheck: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulation
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
77TT1500ML-CS
✓ verified
Application
Electric motor-driven tunnel thruster for bow/stern docking, slow speed maneuvering, emergency steering, station keeping
Common Failures & Inspection Points
- Area: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensionsCheck: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensions
- Area: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrCheck: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrainment
- Area: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfacesCheck: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfaces
- Area: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating watersCheck: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating waters
- Area: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to cCheck: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to check due to integrated hydraulic lubrication)
- Area: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestCheck: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestion
- Area: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal areaCheck: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal area
- Area: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulatioCheck: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulation
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
90TT2000ML-CS
✓ verified
Application
Electric motor-driven tunnel thruster for bow/stern docking, slow speed maneuvering, emergency steering, station keeping
Common Failures & Inspection Points
- Area: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensionsCheck: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensions
- Area: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrCheck: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrainment
- Area: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfacesCheck: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfaces
- Area: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating watersCheck: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating waters
- Area: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to cCheck: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to check due to integrated hydraulic lubrication)
- Area: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestCheck: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestion
- Area: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal areaCheck: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal area
- Area: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulatioCheck: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulation
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
104TT2500ML-CS
✓ verified
Application
Electric motor-driven tunnel thruster for bow/stern docking, slow speed maneuvering, emergency steering, station keeping
Common Failures & Inspection Points
- Area: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensionsCheck: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensions
- Area: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrCheck: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrainment
- Area: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfacesCheck: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfaces
- Area: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating watersCheck: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating waters
- Area: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to cCheck: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to check due to integrated hydraulic lubrication)
- Area: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestCheck: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestion
- Area: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal areaCheck: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal area
- Area: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulatioCheck: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulation
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
117TT3000ML-CS
✓ verified
Application
Electric motor-driven tunnel thruster for bow/stern docking, slow speed maneuvering, emergency steering, station keeping
Common Failures & Inspection Points
- Area: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensionsCheck: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensions
- Area: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrCheck: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrainment
- Area: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfacesCheck: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfaces
- Area: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating watersCheck: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating waters
- Area: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to cCheck: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to check due to integrated hydraulic lubrication)
- Area: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestCheck: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestion
- Area: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal areaCheck: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal area
- Area: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulatioCheck: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulation
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
126TT4000ML-CS
✓ verified
Application
Electric motor-driven tunnel thruster for bow/stern docking, slow speed maneuvering, emergency steering, station keeping
Common Failures & Inspection Points
- Area: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensionsCheck: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensions
- Area: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrCheck: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrainment
- Area: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfacesCheck: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfaces
- Area: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating watersCheck: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating waters
- Area: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to cCheck: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to check due to integrated hydraulic lubrication)
- Area: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestCheck: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestion
- Area: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal areaCheck: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal area
- Area: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulatioCheck: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulation
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
136TT5000ML-CS
✓ verified
Application
Electric motor-driven tunnel thruster for bow/stern docking, slow speed maneuvering, emergency steering, station keeping
Common Failures & Inspection Points
- Area: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensionsCheck: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensions
- Area: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrCheck: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrainment
- Area: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfacesCheck: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfaces
- Area: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating watersCheck: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating waters
- Area: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to cCheck: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to check due to integrated hydraulic lubrication)
- Area: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestCheck: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestion
- Area: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal areaCheck: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal area
- Area: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulatioCheck: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulation
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
16TT70HAL
✓ verified
Application
Hydraulic tunnel thruster for bow/stern docking, slow speed maneuvering, emergency steering, station keeping
Common Failures & Inspection Points
- Area: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensionsCheck: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensions
- Area: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrCheck: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrainment
- Area: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfacesCheck: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfaces
- Area: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating watersCheck: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating waters
- Area: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to cCheck: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to check due to integrated hydraulic lubrication)
- Area: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestCheck: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestion
- Area: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal areaCheck: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal area
- Area: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulatioCheck: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulation
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
30TT200-AL
✓ verified
Application
Hydraulic tunnel thruster for bow/stern docking, slow speed maneuvering, emergency steering, station keeping
Common Failures & Inspection Points
- Area: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensionsCheck: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensions
- Area: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrCheck: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrainment
- Area: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfacesCheck: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfaces
- Area: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating watersCheck: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating waters
- Area: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to cCheck: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to check due to integrated hydraulic lubrication)
- Area: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestCheck: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestion
- Area: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal areaCheck: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal area
- Area: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulatioCheck: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulation
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
36TT250-CS
✓ verified
Application
Hydraulic tunnel thruster for bow/stern docking, slow speed maneuvering, emergency steering, station keeping
Common Failures & Inspection Points
- Area: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensionsCheck: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensions
- Area: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrCheck: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrainment
- Area: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfacesCheck: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfaces
- Area: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating watersCheck: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating waters
- Area: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to cCheck: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to check due to integrated hydraulic lubrication)
- Area: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestCheck: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestion
- Area: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal areaCheck: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal area
- Area: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulatioCheck: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulation
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
42TT350H-CS
✓ verified
Application
Hydraulic tunnel thruster for bow/stern docking, slow speed maneuvering, emergency steering, station keeping
Common Failures & Inspection Points
- Area: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensionsCheck: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensions
- Area: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrCheck: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrainment
- Area: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfacesCheck: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfaces
- Area: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating watersCheck: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating waters
- Area: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to cCheck: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to check due to integrated hydraulic lubrication)
- Area: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestCheck: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestion
- Area: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal areaCheck: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal area
- Area: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulatioCheck: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulation
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
TH200MLR
✓ verified
· 150.0 kW
Weight: 4173.0 kg
Application
Retractable tunnel thruster (electric motor-driven) for bow/stern docking, slow speed maneuvering, emergency steering, station keeping with azimuth propulsion
Propeller cm
91
Speed (1/min)
1800
Common Failures & Inspection Points
- Area: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensionsCheck: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensions
- Area: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrCheck: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrainment
- Area: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfacesCheck: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfaces
- Area: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating watersCheck: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating waters
- Area: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to cCheck: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to check due to integrated hydraulic lubrication)
- Area: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestCheck: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestion
- Area: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal areaCheck: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal area
- Area: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulatioCheck: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulation
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
TH300MLR
✓ verified
Application
Retractable tunnel thruster (electric motor-driven) for bow/stern docking, slow speed maneuvering, emergency steering, station keeping with azimuth propulsion
Common Failures & Inspection Points
- Area: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensionsCheck: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensions
- Area: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrCheck: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrainment
- Area: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfacesCheck: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfaces
- Area: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating watersCheck: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating waters
- Area: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to cCheck: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to check due to integrated hydraulic lubrication)
- Area: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestCheck: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestion
- Area: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal areaCheck: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal area
- Area: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulatioCheck: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulation
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
TH500MLR
✓ verified
Application
Retractable tunnel thruster (electric motor-driven, canister style) for bow/stern docking, slow speed maneuvering, emergency steering, station keeping with azimuth propulsion
Common Failures & Inspection Points
- Area: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensionsCheck: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensions
- Area: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrCheck: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrainment
- Area: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfacesCheck: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfaces
- Area: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating watersCheck: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating waters
- Area: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to cCheck: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to check due to integrated hydraulic lubrication)
- Area: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestCheck: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestion
- Area: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal areaCheck: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal area
- Area: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulatioCheck: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulation
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
TH750MLR
✓ verified
Application
Retractable tunnel thruster (electric motor-driven, canister style) for bow/stern docking, slow speed maneuvering, emergency steering, station keeping with azimuth propulsion
Common Failures & Inspection Points
- Area: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensionsCheck: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensions
- Area: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrCheck: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrainment
- Area: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfacesCheck: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfaces
- Area: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating watersCheck: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating waters
- Area: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to cCheck: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to check due to integrated hydraulic lubrication)
- Area: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestCheck: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestion
- Area: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal areaCheck: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal area
- Area: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulatioCheck: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulation
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
TH1000MLR
✓ verified
Application
Retractable tunnel thruster (electric motor-driven, canister style) for bow/stern docking, slow speed maneuvering, emergency steering, station keeping with azimuth propulsion
Common Failures & Inspection Points
- Area: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensionsCheck: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensions
- Area: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrCheck: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrainment
- Area: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfacesCheck: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfaces
- Area: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating watersCheck: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating waters
- Area: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to cCheck: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to check due to integrated hydraulic lubrication)
- Area: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestCheck: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestion
- Area: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal areaCheck: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal area
- Area: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulatioCheck: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulation
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
TH1250MLR
✓ verified
Application
Retractable tunnel thruster (electric motor-driven, canister style) for bow/stern docking, slow speed maneuvering, emergency steering, station keeping with azimuth propulsion
Common Failures & Inspection Points
- Area: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensionsCheck: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensions
- Area: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrCheck: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrainment
- Area: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfacesCheck: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfaces
- Area: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating watersCheck: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating waters
- Area: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to cCheck: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to check due to integrated hydraulic lubrication)
- Area: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestCheck: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestion
- Area: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal areaCheck: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal area
- Area: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulatioCheck: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulation
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
TH1500MLR
✓ verified
Application
Retractable tunnel thruster (electric motor-driven, stem style) for bow/stern docking, slow speed maneuvering, emergency steering, station keeping with azimuth propulsion
Common Failures & Inspection Points
- Area: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensionsCheck: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensions
- Area: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrCheck: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrainment
- Area: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfacesCheck: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfaces
- Area: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating watersCheck: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating waters
- Area: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to cCheck: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to check due to integrated hydraulic lubrication)
- Area: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestCheck: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestion
- Area: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal areaCheck: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal area
- Area: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulatioCheck: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulation
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
TH2000MLR
✓ verified
Application
Retractable tunnel thruster (electric motor-driven, stem style) for bow/stern docking, slow speed maneuvering, emergency steering, station keeping with azimuth propulsion
Common Failures & Inspection Points
- Area: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensionsCheck: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensions
- Area: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrCheck: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrainment
- Area: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfacesCheck: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfaces
- Area: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating watersCheck: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating waters
- Area: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to cCheck: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to check due to integrated hydraulic lubrication)
- Area: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestCheck: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestion
- Area: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal areaCheck: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal area
- Area: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulatioCheck: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulation
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
TH2500MLR
✓ verified
Application
Retractable tunnel thruster (electric motor-driven, stem style) for bow/stern docking, slow speed maneuvering, emergency steering, station keeping with azimuth propulsion
Common Failures & Inspection Points
- Area: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensionsCheck: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensions
- Area: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrCheck: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrainment
- Area: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfacesCheck: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfaces
- Area: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating watersCheck: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating waters
- Area: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to cCheck: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to check due to integrated hydraulic lubrication)
- Area: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestCheck: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestion
- Area: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal areaCheck: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal area
- Area: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulatioCheck: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulation
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
TH3000MLR
✓ verified
Application
Retractable tunnel thruster (electric motor-driven, stem style) for bow/stern docking, slow speed maneuvering, emergency steering, station keeping with azimuth propulsion
Common Failures & Inspection Points
- Area: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensionsCheck: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensions
- Area: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrCheck: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrainment
- Area: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfacesCheck: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfaces
- Area: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating watersCheck: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating waters
- Area: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to cCheck: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to check due to integrated hydraulic lubrication)
- Area: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestCheck: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestion
- Area: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal areaCheck: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal area
- Area: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulatioCheck: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulation
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
TH4000MLR
✓ verified
Application
Retractable tunnel thruster (electric motor-driven, stem/canister style) for bow/stern docking, slow speed maneuvering, emergency steering, station keeping with azimuth propulsion
Common Failures & Inspection Points
- Area: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensionsCheck: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensions
- Area: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrCheck: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrainment
- Area: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfacesCheck: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfaces
- Area: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating watersCheck: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating waters
- Area: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to cCheck: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to check due to integrated hydraulic lubrication)
- Area: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestCheck: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestion
- Area: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal areaCheck: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal area
- Area: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulatioCheck: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulation
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
TH5000MLR
✓ verified
Application
Retractable tunnel thruster (electric motor-driven, stem/canister style) for bow/stern docking, slow speed maneuvering, emergency steering, station keeping with azimuth propulsion
Common Failures & Inspection Points
- Area: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensionsCheck: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensions
- Area: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrCheck: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrainment
- Area: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfacesCheck: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfaces
- Area: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating watersCheck: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating waters
- Area: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to cCheck: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to check due to integrated hydraulic lubrication)
- Area: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestCheck: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestion
- Area: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal areaCheck: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal area
- Area: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulatioCheck: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulation
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
TH6000MLR
✓ verified
Application
Retractable tunnel thruster (electric motor-driven, canister style) for bow/stern docking, slow speed maneuvering, emergency steering, station keeping with azimuth propulsion
Common Failures & Inspection Points
- Area: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensionsCheck: Zinc anode condition assessment: Replace MIL-Spec zinc anodes with cadmium content when anode size drops to 10% or less of original dimensions
- Area: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrCheck: Tunnel submergence verification: Confirm tunnel top is submerged minimum 1 tunnel diameter below minimum light draft waterline to prevent vortexing and air entrainment
- Area: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfacesCheck: Propeller inspection and debris removal: Check fixed-pitch propeller for wear, cavitation damage, and clear debris from tunnel entrance and propeller surfaces
- Area: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating watersCheck: Ceramic tunnel coating inspection: Examine ceramic coating for erosion damage caused by sand and silt in operating waters
- Area: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to cCheck: Hydraulic system and fluid condition: Monitor hydraulic fluid condition, pressure system integrity, and filtration (no separate grease points or oil levels to check due to integrated hydraulic lubrication)
- Area: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestCheck: Cavitation and noise assessment during operation: Monitor for abnormal cavitation indicators, excessive noise, vibration or shock loads that indicate air ingestion
- Area: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal areaCheck: Welded tunnel extension integrity: Check welds and seal areas if tunnel was extended through hull modification; avoid sand-blasting propeller shaft seal area
- Area: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulatioCheck: Inlet grid alignment (if equipped): Verify inlet grid alignment is parallel to predominant water flow direction to minimize pressure drop and debris accumulation
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
Jastram
52 ✓ 7 verified
BU50F, BU60F, BU90F, BU100F
Model Number
TAM0000113
BU 02F
✓ verified
Application
Tunnel Thruster (Bow/Stern)
Common Failures & Inspection Points
- Area: Propeller condition: inspection for wear, material fatigue, cavitation damage and foreign objectsCheck: Propeller condition: inspection for wear, material fatigue, cavitation damage and foreign objects
- Area: Shaft seal and seal rings: inspection for wear, oil leakage and water ingress (Viton seal rings, white metal seal)Check: Shaft seal and seal rings: inspection for wear, oil leakage and water ingress (Viton seal rings, white metal seal)
- Area: Cathodic protection/sacrificial anodes: inspection of zinc coating (steel) and renewal at least annuallyCheck: Cathodic protection/sacrificial anodes: inspection of zinc coating (steel) and renewal at least annually
- Area: Tunnel opening and water flow: inspection for fouling (algae, barnacles), sludging and flow obstructionCheck: Tunnel opening and water flow: inspection for fouling (algae, barnacles), sludging and flow obstruction
- Area: Kavitationsschutzring: Überprüfung des Edelstahl-Schutzrings an der Propellerspitze auf BeschädigungenCheck: Kavitationsschutzring: Überprüfung des Edelstahl-Schutzrings an der Propellerspitze auf Beschädigungen
- Area: Electric motor drive/couplings: inspection for wear, corrosion, misalignment and bearing wearCheck: Electric motor drive/couplings: inspection for wear, corrosion, misalignment and bearing wear
- Area: Pressure equalisation system and oil tank: inspection of oil level, oil quality, moisture content and leaksCheck: Pressure equalisation system and oil tank: inspection of oil level, oil quality, moisture content and leaks
- Area: Cavitation inspection: inspection for tunnel flooding during operation and noise/vibration inspectionCheck: Cavitation inspection: inspection for tunnel flooding during operation and noise/vibration inspection
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
BU 20F
✓ verified
Application
Tunnel Thruster (Bow/Stern)
Common Failures & Inspection Points
- Area: Propeller condition: inspection for wear, material fatigue, cavitation damage and foreign objectsCheck: Propeller condition: inspection for wear, material fatigue, cavitation damage and foreign objects
- Area: Shaft seal and seal rings: inspection for wear, oil leakage and water ingress (Viton seal rings, white metal seal)Check: Shaft seal and seal rings: inspection for wear, oil leakage and water ingress (Viton seal rings, white metal seal)
- Area: Cathodic protection/sacrificial anodes: inspection of zinc coating (steel) and renewal at least annuallyCheck: Cathodic protection/sacrificial anodes: inspection of zinc coating (steel) and renewal at least annually
- Area: Tunnel opening and water flow: inspection for fouling (algae, barnacles), sludging and flow obstructionCheck: Tunnel opening and water flow: inspection for fouling (algae, barnacles), sludging and flow obstruction
- Area: Kavitationsschutzring: Überprüfung des Edelstahl-Schutzrings an der Propellerspitze auf BeschädigungenCheck: Kavitationsschutzring: Überprüfung des Edelstahl-Schutzrings an der Propellerspitze auf Beschädigungen
- Area: Electric motor drive/couplings: inspection for wear, corrosion, misalignment and bearing wearCheck: Electric motor drive/couplings: inspection for wear, corrosion, misalignment and bearing wear
- Area: Pressure equalisation system and oil tank: inspection of oil level, oil quality, moisture content and leaksCheck: Pressure equalisation system and oil tank: inspection of oil level, oil quality, moisture content and leaks
- Area: Cavitation inspection: inspection for tunnel flooding during operation and noise/vibration inspectionCheck: Cavitation inspection: inspection for tunnel flooding during operation and noise/vibration inspection
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
BU 40F
✓ verified
Application
Tunnel Thruster (Bow/Stern)
Common Failures & Inspection Points
- Area: Propeller condition: inspection for wear, material fatigue, cavitation damage and foreign objectsCheck: Propeller condition: inspection for wear, material fatigue, cavitation damage and foreign objects
- Area: Shaft seal and seal rings: inspection for wear, oil leakage and water ingress (Viton seal rings, white metal seal)Check: Shaft seal and seal rings: inspection for wear, oil leakage and water ingress (Viton seal rings, white metal seal)
- Area: Cathodic protection/sacrificial anodes: inspection of zinc coating (steel) and renewal at least annuallyCheck: Cathodic protection/sacrificial anodes: inspection of zinc coating (steel) and renewal at least annually
- Area: Tunnel opening and water flow: inspection for fouling (algae, barnacles), sludging and flow obstructionCheck: Tunnel opening and water flow: inspection for fouling (algae, barnacles), sludging and flow obstruction
- Area: Kavitationsschutzring: Überprüfung des Edelstahl-Schutzrings an der Propellerspitze auf BeschädigungenCheck: Kavitationsschutzring: Überprüfung des Edelstahl-Schutzrings an der Propellerspitze auf Beschädigungen
- Area: Electric motor drive/couplings: inspection for wear, corrosion, misalignment and bearing wearCheck: Electric motor drive/couplings: inspection for wear, corrosion, misalignment and bearing wear
- Area: Pressure equalisation system and oil tank: inspection of oil level, oil quality, moisture content and leaksCheck: Pressure equalisation system and oil tank: inspection of oil level, oil quality, moisture content and leaks
- Area: Cavitation inspection: inspection for tunnel flooding during operation and noise/vibration inspectionCheck: Cavitation inspection: inspection for tunnel flooding during operation and noise/vibration inspection
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
[08.08.2026] Datenblattlink entfernt (nicht erreichbar): https://parts.shipcare360.com/manoeuvring-thruster-tunnel-jastram-bu-40f/
BU 60F
✓ verified
Application
Tunnel Thruster (Bow/Stern)
Common Failures & Inspection Points
- Area: Propeller condition: inspection for wear, material fatigue, cavitation damage and foreign objectsCheck: Propeller condition: inspection for wear, material fatigue, cavitation damage and foreign objects
- Area: Shaft seal and seal rings: inspection for wear, oil leakage and water ingress (Viton seal rings, white metal seal)Check: Shaft seal and seal rings: inspection for wear, oil leakage and water ingress (Viton seal rings, white metal seal)
- Area: Cathodic protection/sacrificial anodes: inspection of zinc coating (steel) and renewal at least annuallyCheck: Cathodic protection/sacrificial anodes: inspection of zinc coating (steel) and renewal at least annually
- Area: Tunnel opening and water flow: inspection for fouling (algae, barnacles), sludging and flow obstructionCheck: Tunnel opening and water flow: inspection for fouling (algae, barnacles), sludging and flow obstruction
- Area: Kavitationsschutzring: Überprüfung des Edelstahl-Schutzrings an der Propellerspitze auf BeschädigungenCheck: Kavitationsschutzring: Überprüfung des Edelstahl-Schutzrings an der Propellerspitze auf Beschädigungen
- Area: Electric motor drive/couplings: inspection for wear, corrosion, misalignment and bearing wearCheck: Electric motor drive/couplings: inspection for wear, corrosion, misalignment and bearing wear
- Area: Pressure equalisation system and oil tank: inspection of oil level, oil quality, moisture content and leaksCheck: Pressure equalisation system and oil tank: inspection of oil level, oil quality, moisture content and leaks
- Area: Cavitation inspection: inspection for tunnel flooding during operation and noise/vibration inspectionCheck: Cavitation inspection: inspection for tunnel flooding during operation and noise/vibration inspection
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
BU 90F
✓ verified
Application
Tunnel Thruster (Bow/Stern)
Common Failures & Inspection Points
- Area: Propeller condition: inspection for wear, material fatigue, cavitation damage and foreign objectsCheck: Propeller condition: inspection for wear, material fatigue, cavitation damage and foreign objects
- Area: Shaft seal and seal rings: inspection for wear, oil leakage and water ingress (Viton seal rings, white metal seal)Check: Shaft seal and seal rings: inspection for wear, oil leakage and water ingress (Viton seal rings, white metal seal)
- Area: Cathodic protection/sacrificial anodes: inspection of zinc coating (steel) and renewal at least annuallyCheck: Cathodic protection/sacrificial anodes: inspection of zinc coating (steel) and renewal at least annually
- Area: Tunnel opening and water flow: inspection for fouling (algae, barnacles), sludging and flow obstructionCheck: Tunnel opening and water flow: inspection for fouling (algae, barnacles), sludging and flow obstruction
- Area: Kavitationsschutzring: Überprüfung des Edelstahl-Schutzrings an der Propellerspitze auf BeschädigungenCheck: Kavitationsschutzring: Überprüfung des Edelstahl-Schutzrings an der Propellerspitze auf Beschädigungen
- Area: Electric motor drive/couplings: inspection for wear, corrosion, misalignment and bearing wearCheck: Electric motor drive/couplings: inspection for wear, corrosion, misalignment and bearing wear
- Area: Pressure equalisation system and oil tank: inspection of oil level, oil quality, moisture content and leaksCheck: Pressure equalisation system and oil tank: inspection of oil level, oil quality, moisture content and leaks
- Area: Cavitation inspection: inspection for tunnel flooding during operation and noise/vibration inspectionCheck: Cavitation inspection: inspection for tunnel flooding during operation and noise/vibration inspection
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
BU 40
✓ verified
Application
Tunnel Thruster (Bow/Stern)
Common Failures & Inspection Points
- Area: Propeller condition: inspection for wear, material fatigue, cavitation damage and foreign objectsCheck: Propeller condition: inspection for wear, material fatigue, cavitation damage and foreign objects
- Area: Shaft seal and seal rings: inspection for wear, oil leakage and water ingress (Viton seal rings, white metal seal)Check: Shaft seal and seal rings: inspection for wear, oil leakage and water ingress (Viton seal rings, white metal seal)
- Area: Cathodic protection/sacrificial anodes: inspection of zinc coating (steel) and renewal at least annuallyCheck: Cathodic protection/sacrificial anodes: inspection of zinc coating (steel) and renewal at least annually
- Area: Tunnel opening and water flow: inspection for fouling (algae, barnacles), sludging and flow obstructionCheck: Tunnel opening and water flow: inspection for fouling (algae, barnacles), sludging and flow obstruction
- Area: Kavitationsschutzring: Überprüfung des Edelstahl-Schutzrings an der Propellerspitze auf BeschädigungenCheck: Kavitationsschutzring: Überprüfung des Edelstahl-Schutzrings an der Propellerspitze auf Beschädigungen
- Area: Electric motor drive/couplings: inspection for wear, corrosion, misalignment and bearing wearCheck: Electric motor drive/couplings: inspection for wear, corrosion, misalignment and bearing wear
- Area: Pressure equalisation system and oil tank: inspection of oil level, oil quality, moisture content and leaksCheck: Pressure equalisation system and oil tank: inspection of oil level, oil quality, moisture content and leaks
- Area: Cavitation inspection: inspection for tunnel flooding during operation and noise/vibration inspectionCheck: Cavitation inspection: inspection for tunnel flooding during operation and noise/vibration inspection
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
BU 100
✓ verified
Application
Tunnel Thruster (Bow/Stern)
Common Failures & Inspection Points
- Area: Propeller condition: inspection for wear, material fatigue, cavitation damage and foreign objectsCheck: Propeller condition: inspection for wear, material fatigue, cavitation damage and foreign objects
- Area: Shaft seal and seal rings: inspection for wear, oil leakage and water ingress (Viton seal rings, white metal seal)Check: Shaft seal and seal rings: inspection for wear, oil leakage and water ingress (Viton seal rings, white metal seal)
- Area: Cathodic protection/sacrificial anodes: inspection of zinc coating (steel) and renewal at least annuallyCheck: Cathodic protection/sacrificial anodes: inspection of zinc coating (steel) and renewal at least annually
- Area: Tunnel opening and water flow: inspection for fouling (algae, barnacles), sludging and flow obstructionCheck: Tunnel opening and water flow: inspection for fouling (algae, barnacles), sludging and flow obstruction
- Area: Kavitationsschutzring: Überprüfung des Edelstahl-Schutzrings an der Propellerspitze auf BeschädigungenCheck: Kavitationsschutzring: Überprüfung des Edelstahl-Schutzrings an der Propellerspitze auf Beschädigungen
- Area: Electric motor drive/couplings: inspection for wear, corrosion, misalignment and bearing wearCheck: Electric motor drive/couplings: inspection for wear, corrosion, misalignment and bearing wear
- Area: Pressure equalisation system and oil tank: inspection of oil level, oil quality, moisture content and leaksCheck: Pressure equalisation system and oil tank: inspection of oil level, oil quality, moisture content and leaks
- Area: Cavitation inspection: inspection for tunnel flooding during operation and noise/vibration inspectionCheck: Cavitation inspection: inspection for tunnel flooding during operation and noise/vibration inspection
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
JA-TT-50 bow
unverified
· 50.0 kW
· electric tunnel thruster
Power (kW)
50
Thrust (kN)
6.0
Diameter (mm)
540
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (6 kN from 50 kW)
- Compact 540 mm diameter allows installation in limited hull space
- Low acoustic signature and vibration, suitable for passenger or offshore vessels
- Proven Jastram reliability with robust bearing and seal design
- Straightforward integration with ship’s electric power system
Weaknesses
- Maximum thrust may be insufficient for large tankers or high‑wind port operations
- Requires dedicated 400 V three‑phase supply and associated cabling
- Higher upfront cost compared with generic low‑cost thrusters
- Maintenance of hydraulic seals (if hydraulically assisted) can add downtime
- Cavitation risk at full load in shallow water
Typical Vessels:
Handymax Bulk CarrierFeeder Container ShipOffshore Supply VesselCruise Ship (mid‑size)Ro‑Ro Ferry
Decision Guide: Choose if: you need a reliable, low‑noise bow thruster for vessels up to ~30 000 DWT where space is limited and precise maneuvering is required. Avoid if: the vessel demands higher thrust (>8 kN) or budget constraints favour lower‑spec alternatives.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
JA-TT-50 stern
unverified
· 50.0 kW
· tunnel thruster
Power (kW)
50
Thrust (kN)
6.0
Diameter (mm)
540
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (6 kN at only 50 kW)
- Compact 540 mm diameter fits in limited stern space
- Robust Jastram design with proven reliability in harsh marine environments
- Low acoustic signature, suitable for noise‑sensitive operations
- Standardized mounting and wiring simplify installation and integration
Weaknesses
- Maximum thrust may be insufficient for large vessels or high‑wind conditions
- Potential cavitation at full power if water flow is restricted
- Maintenance access can be limited when installed in tight stern compartments
- Power consumption relatively high for small workboats that could use electric alternatives
- Corrosion risk if duct material and coatings are not regularly inspected
Typical Vessels:
Offshore supply vesselCoastal cargo shipFerryWorkboat / tug‑assist boatSmall product tanker
Decision Guide: Choose if: you need a reliable, compact stern thruster delivering up to 6 kN for vessels under ~5,000 gt operating in confined ports or offshore support roles, and you value proven Jastram durability. Avoid if: the vessel requires higher thrust (>10 kN), operates at high speeds where cavitation becomes critical, or you prefer a fully electric low‑power solution.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
JA-TT-75 bow
unverified
· 75.0 kW
· tunnel thruster
Power (kW)
75
Thrust (kN)
9.0
Diameter (mm)
560
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (9 kN @ 75 kW) for its size
- Compact 560 mm tunnel fits vessels with limited hull space
- Proven Jastram reliability and low maintenance intervals
- Integrated control unit compatible with most ship bridge systems
- Suitable for both new builds and retro‑fits on medium‑size ships
Weaknesses
- Maximum 75 kW power may be insufficient for large vessels or heavy weather maneuvering
- Fixed tunnel geometry limits thrust optimisation at very low speeds (cavitation risk)
- Installation requires hull penetration and structural reinforcement
- Limited thrust directionality compared with azimuth thrusters
- Standard model lacks built‑in redundancy; optional backup system adds cost
Typical Vessels:
Coastal tankerFeeder container shipOffshore supply vesselCruise ferrySmall Ro‑Ro vessel
Decision Guide: Choose if: you need a reliable, compact bow thruster for vessels up to ~10 000 gt operating in ports, harbours or offshore terminals where space is limited and 75 kW power suffices. Avoid if: the ship requires higher thrust margins (e.g., large tankers, harsh sea states) or prefers 360° azimuth capability.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
JA-TT-75 stern
unverified
· 75.0 kW
· tunnel thruster
Power (kW)
75
Thrust (kN)
9.0
Diameter (mm)
560
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (9 kN from 75 kW) for its size class
- Compact 560 mm tunnel diameter fits into limited hull spaces
- Robust, low‑maintenance design typical of Jastram marine equipment
- Integrated control wiring compatible with most ship bridge systems
- Proven reliability in coastal and offshore support vessels
Weaknesses
- Maximum thrust may be insufficient for large DP‑class ships or heavy‑weather berthing
- Tunnel geometry can generate hull vibration and noise at high RPMs
- Installation requires a stern tunnel cut‑out, adding dockyard time and cost
- Performance degrades in strong currents or when the hull is heavily fouled
- Limited to fixed‑direction thrust; cannot provide azimuthal steering
Typical Vessels:
Offshore supply vesselCoastal cargo shipRo‑Ro ferryPassenger ferrySmall container or bulk carrier (up to ~10,000 DWT)
Decision Guide: Choose if: you need a reliable, cost‑effective stern thruster for vessels up to about 10 k DWT with limited hull space and standard maneuvering requirements. Avoid if: the ship requires high thrust for DP operations, large DP‑class tankers, or an azimuthing thruster for 360° steering.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
JA-TT-100 bow
unverified
· 100.0 kW
· tunnel bow thruster
Power (kW)
100
Thrust (kN)
12.0
Diameter (mm)
580
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Compact tunnel design fits within standard hull sections without protruding pods
- Good thrust‑to‑power ratio (12 kN @ 100 kW) for vessels up to ~30,000 DWT
- Low vibration and noise compared with external azimuth units
- Straightforward deck‑level maintenance access through removable covers
Weaknesses
- Maximum thrust limited to 12 kN – may be insufficient for large tankers or high‑speed DP vessels
- Installation requires hull penetration and structural reinforcement
- Tunnel flow can cause slight increase in hull resistance when the thruster is not in use
- Noise and cavitation become noticeable at full power on smaller hulls
Typical Vessels:
Offshore supply vesselFerryCruise ship (mid‑size)Container feederBulk carrier (up to ~30,000 DWT)
Decision Guide: Choose if you need a moderate‑power bow thruster that fits within the hull envelope and offers low vibration for vessels up to about 30,000 DWT. Avoid if your vessel requires higher thrust levels (>15 kN), prefers an azimuth pod for 360° thrust, or has strict weight/space constraints that preclude a tunnel installation.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
JA-TT-100 stern
unverified
· 100.0 kW
· tunnel thruster
Power (kW)
100
Thrust (kN)
12.0
Diameter (mm)
580
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (12 kN at only 100 kW)
- Compact hull integration with a 580 mm tunnel diameter
- Integrated control electronics from Jastram for easy installation and monitoring
- Proven reliability of the Jastram brand in commercial service
- Low vibration and acoustic signature compared with external azimuth units
Weaknesses
- Limited thrust capacity relative to larger azimuth thrusters, unsuitable for high‑power DP requirements
- Potential cavitation at high propeller speeds, especially in shallow water
- Requires hull penetration and internal space, complicating retrofits
- Maintenance access can be restricted by the tunnel geometry
- Less effective for vessels operating in heavy seas or requiring rapid thrust reversal
Typical Vessels:
Handymax bulk carrierMedium‑range tankerFeeder container shipOffshore supply vesselCruise ship tender
Certifications:
DNV
Decision Guide: Choose the JA‑TT‑100 when a compact, high‑efficiency stern thruster is needed for vessels up to ~150 m LOA that require reliable low‑speed maneuvering or modest DP assistance. Avoid it on large ships demanding >200 kW thrust per unit, on vessels operating in very shallow water where cavitation risk is critical, or when a full azimuth system is required for high‑maneuverability tasks.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
JA-TT-150 bow
unverified
· 150.0 kW
· tunnel thruster
Power (kW)
150
Thrust (kN)
18.0
Diameter (mm)
620
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (18 kN from 150 kW)
- Compact 620 mm duct fits vessels with limited hull space
- Water‑lubricated bearings reduce wear and extend service intervals
- Low acoustic and vibration signature, beneficial for passenger ships
- Optional integrated control unit for precise helm response
Weaknesses
- Requires sufficient draft; not ideal for very shallow installations
- Fixed‑direction thrust – no azimuth capability
- Bearing seals need regular inspection in high‑salinity environments
- Performance can degrade in highly turbulent or debris‑laden water
- Higher power consumption compared with newer pump‑jet thrusters of similar rating
Typical Vessels:
Handymax Bulk CarrierFeeder Container ShipOffshore Supply VesselCruise FerryCoastal Tanker
Certifications:
DNV
Decision Guide: Choose if you need a compact, high‑thrust bow thruster for vessels up to ~30 m beam where space is limited and low noise is important. Avoid if the ship operates in very shallow water, requires azimuth thrusting, or seeks the lowest possible power consumption.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
JA-TT-150 stern
unverified
· 150.0 kW
· tunnel thruster
Power (kW)
150
Thrust (kN)
18.0
Diameter (mm)
620
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (18 kN at 150 kW) for its size
- Compact 620 mm tunnel fits vessels with limited hull space
- Water‑lubricated bearings reduce wear and maintenance intervals
- Stainless‑steel housing provides excellent corrosion resistance in marine environments
- Integrated control electronics compatible with most DP and bow‑thruster consoles
Weaknesses
- Maximum thrust of 18 kN may be insufficient for large vessels or high‑wind conditions
- Noise level rises noticeably at full power, which can affect crew comfort on passenger ships
- Installation requires hull penetration and structural reinforcement, adding dock time
- Power consumption is relatively high for small craft that need only modest maneuverability
Typical Vessels:
Handymax bulk carrierProduct tanker (up to ~30 000 dwt)Offshore supply vesselCruise ship (mid‑size)Container feeder
Certifications:
DNV
Decision Guide: Choose if you need a reliable medium‑power stern thruster for vessels up to ~30 000 dwt where hull space is limited and robust corrosion resistance is required. Avoid if the vessel demands higher thrust (>25 kN), ultra‑low acoustic signature, or if installation time must be minimal.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
JA-TT-200 bow
unverified
· 200.0 kW
· tunnel thruster
Power (kW)
200
Thrust (kN)
24.0
Diameter (mm)
660
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (≈24 kN from 200 kW) for compact vessels
- Robust tunnel construction reduces blade wear and vibration
- Integrated control electronics compatible with most ship bridge systems
- Proven track record on a variety of commercial ships
- Relatively low installation space compared to azimuth pods
Weaknesses
- Fixed‑direction thrust; requires separate steering gear for vectoring
- Tunnel liner wear can increase maintenance intervals in high‑sediment waters
- Noise and cavitation levels higher than some ducted propeller alternatives at full power
- Power demand may be limiting on vessels with restricted electrical generation capacity
Typical Vessels:
Container ships (up to ~15 000 GT)General cargo vesselsOffshore supply & support vesselsCruise ferriesSmall tankers and bulk carriers
Certifications:
DNV GL Class approvalABS classification
Decision Guide: Choose if you need a high‑thrust bow thruster in limited hull space, have sufficient electrical power (≈400 V AC) and require proven reliability for docking or DP support. Avoid if you need full 360° thrust vectoring, ultra‑low acoustic signature, or operate on vessels where tunnel fouling is a major concern.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
JA-TT-200 stern
unverified
· 200.0 kW
· tunnel thruster
Power (kW)
200
Thrust (kN)
24.0
Diameter (mm)
660
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (24 kN) relative to its 200 kW power rating
- Compact 660 mm tunnel fits medium‑size vessel hulls without excessive space penalty
- Robust German engineering with proven reliability in commercial fleets
- Integrated motor cooling system reduces overheating risk during prolonged DP operation
Weaknesses
- Installation requires a large (≈660 mm) hull opening, affecting structural layout
- Cavitation can occur at high RPMs, especially in shallow water conditions
- Fixed‑direction thrust; less flexible than azimuth or pod thrusters for certain maneuvers
- Power consumption is higher than some newer ducted‑propeller designs offering similar thrust
Typical Vessels:
Container shipBulk carrierProduct tankerCruise liner (mid‑size)Offshore supply vessel
Decision Guide: Choose if: you need a proven, high‑thrust stern thruster for vessels up to ~30 000 DWT with limited hull space and require reliable DP assistance. Avoid if: you prefer azimuthing thrust for maximum maneuverability or have strict noise/cavitation limits in very shallow ports.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
JA-TT-250 bow
unverified
· 250.0 kW
· tunnel thruster
Power (kW)
250
Thrust (kN)
30.0
Diameter (mm)
700
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (30 kN at 250 kW) for strong low‑speed maneuvering
- Compact 700 mm tunnel fits vessels with limited bow space
- Stainless‑steel housing and water‑cooled copper windings provide excellent corrosion resistance and durability
- Low‑cavitation impeller design reduces wear and prolongs service life
- Ready‑to‑install control unit compatible with standard VFD systems
Weaknesses
- Designed for bow installation only; not interchangeable with stern positions
- Relatively high power consumption compared with smaller thrusters, impacting fuel use when operated continuously
- Requires significant hull penetration and reinforcement during installation
- Acoustic noise level higher than that of azimuth or pod‑type thrusters in the same power class
- Maintenance of sealed bearings can be more demanding in harsh marine environments
Typical Vessels:
Container shipBulk carrierCruise linerOffshore supply vesselFerry
Decision Guide: Choose the JA‑TT‑250 if your vessel needs a high‑thrust bow thruster in a limited space envelope, operates frequently in congested ports or requires DP assistance at low speed. Avoid it if you prefer an azimuth thruster for 360° thrust vectoring, have lower power requirements, or need a stern‑mounted solution.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
JA-TT-250 stern
unverified
· 250.0 kW
· tunnel thruster
Power (kW)
250
Thrust (kN)
30.0
Diameter (mm)
700
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (30 kN at 250 kW) for its size
- Compact, steel‑welded tunnel housing fits well in limited stern spaces
- Robust construction with low‑maintenance moving parts
- Straightforward integration with existing ship control systems
Weaknesses
- Provides thrust only in a fixed azimuth; no 360° vectoring like an azimuth pod
- Hull penetration required, increasing potential for water ingress if not sealed properly
- Higher acoustic and vibration levels compared with pump‑jet designs
- Cavitation risk at high RPMs may limit maximum thrust in shallow water
Typical Vessels:
Offshore Support VesselPlatform Supply VesselCoastal Cargo ShipSmall to medium‑size Tug
Decision Guide: Choose if you need a reliable, high‑thrust stern thruster for vessels with limited aft space and standard maneuvering requirements. Avoid if the vessel requires omnidirectional thrust, ultra‑quiet operation, or operates primarily in very shallow water where cavitation is a concern.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
JA-TT-300 bow
unverified
· 300.0 kW
· tunnel thruster
Power (kW)
300
Thrust (kN)
36.0
Diameter (mm)
740
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (≈36 kN at 300 kW) for strong bow assistance
- Compact duct size (740 mm) fits vessels with limited hull space
- Robust steel housing and proven Jastram engineering ensure long service life
- Relatively low acoustic signature compared with azimuth pods
- Standardised mounting and control interfaces simplify integration
Weaknesses
- Fixed‑direction thrust; cannot rotate like a pod for full 360° coverage
- Higher fuel consumption than electric or hybrid bow thrusters of similar rating
- Potential cavitation at high RPM in shallow water conditions
- Requires dedicated cooling water supply and ventilation space
- Limited to vessels up to roughly 30 000 dwt where thrust demand matches
Typical Vessels:
Handymax Bulk CarrierSmall to medium Tanker (5‑30 k dwt)Offshore Supply VesselCruise Ship (mid‑size)Container Feeder
Certifications:
IMO Type Approval (D‑2)DNV Classification
Decision Guide: Choose if you need a reliable, high‑thrust bow thruster for vessels up to ~30 000 dwt with limited hull space and prefer proven steel tunnel technology. Avoid if the vessel requires full 360° thrust vectoring, ultra‑low noise operation, or has severe power‑budget constraints where electric/hybrid solutions are preferred.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
JA-TT-300 stern
unverified
· 300.0 kW
· tunnel thruster
Power (kW)
300
Thrust (kN)
36.0
Diameter (mm)
740
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (36 kN) suitable for large ships and DP assistance
- Large 740 mm tunnel diameter reduces cavitation and improves efficiency
- Robust Jastram construction known for long service life and low maintenance
- Integrated stern location provides excellent reverse‑thrust control during docking
- Standard 300 kW motor matches common ship power distribution systems
Weaknesses
- Physical size (740 mm tunnel) limits installation on vessels with restricted hull space
- Power demand of 300 kW increases overall fuel consumption when used frequently
- Potential for higher acoustic noise and vibration compared with smaller thrusters
- Stern‑only configuration may not meet vessels that require bow thrust as well
- Initial procurement cost is typically higher than lower‑power alternatives
Typical Vessels:
Container shipBulk carrierCruise linerOffshore supply vesselLNG/LPG carrier
Decision Guide: Choose if: you need a high‑thrust stern thruster for large vessels, have sufficient hull space for a 740 mm tunnel, and require reliable performance for DP or tight‑port maneuvers. Avoid if: vessel size or hull geometry cannot accommodate the large tunnel, power budget is limited, or a bow thruster is also required.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
JA-TT-400 bow
unverified
· 400.0 kW
· tunnel bow thruster
Power (kW)
400
Thrust (kN)
48.0
Diameter (mm)
820
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (48 kN at 400 kW) for strong docking assistance
- Compact tunnel geometry fits within limited hull space
- Robust steel construction with removable cover simplifies routine inspection and maintenance
- Integrated cooling water system reduces overheating during prolonged DP operation
Weaknesses
- Tunnel design is more prone to cavitation at high load compared with azimuthing units
- Requires significant hull penetration and structural reinforcement during installation
- Less maneuverability than a rotating (azimuth) thruster in heavy seas or strong currents
- Noise and vibration levels higher than some low‑speed screw‑type thrusters
Typical Vessels:
Handymax bulk carrierMedium container ship (up to ~10,000 TEU)Offshore supply vesselCruise ferryCoastal tanker
Decision Guide: Choose if: you need a powerful yet compact bow thruster for vessels up to ~30 k GT where hull space is limited and budget favours a proven tunnel design. Avoid if: the vessel operates in extreme weather, requires maximum manoeuvrability (e.g., DP‑class offshore rigs), or when cavitation risk must be minimised.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
JA-TT-400 stern
unverified
· 400.0 kW
· tunnel thruster
Power (kW)
400
Thrust (kN)
48.0
Diameter (mm)
820
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (48 kN @ 400 kW) for effective bow‑/stern‑side thrust
- Compact tunnel diameter (820 mm) fits within typical hull forms without excessive structural intrusion
- Robust stainless‑steel housing provides good corrosion resistance in seawater environments
- Integrated control electronics compatible with common ship bridge consoles and DP systems
- Low vibration and noise levels compared with propeller‑type thrusters
Weaknesses
- Installation requires a sizable tunnel aperture, potentially reducing hull strength if not properly reinforced
- Maintenance access can be limited in tight stern spaces, increasing downtime for overhauls
- Higher upfront cost than basic low‑power thrusters of similar size
- Fixed thrust direction; cannot provide 360° azimuth capability needed for some DP applications
- Performance drops noticeably at very low ship speeds due to reduced water flow through the tunnel
Typical Vessels:
Container ships (up to ~150 m LOA)Bulk carriers (Handymax, Supramax)Product tankers and chemical tankersGeneral cargo vesselsOffshore supply vessels with moderate DP requirements
Decision Guide: Choose if you need a reliable stern thruster delivering >45 kN thrust for vessels up to ~30 kt service speed, where hull space allows an 820 mm tunnel and fixed‑direction thrust is sufficient. Avoid if the vessel requires full azimuth thrust, has severe space constraints in the stern, or operates primarily at very low speeds where tunnel flow is insufficient.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
JA-TT-500 bow
unverified
· 500.0 kW
· tunnel bow thruster
Power (kW)
500
Thrust (kN)
60.0
Diameter (mm)
900
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (60 kN) relative to power rating, suitable for medium‑size vessels requiring strong bow control.
- Ducted design reduces cavitation and improves thrust efficiency in calm to moderate sea states.
- Compact installation footprint compared with azimuth pods, fitting into standard bow tunnel spaces.
- Jastram’s reputation for robust mechanical engineering translates to reliable long‑term operation.
Weaknesses
- Large 900 mm duct diameter may limit placement on vessels with narrow hull forms or restricted bow space.
- 500 kW electrical demand requires a capable shipboard power system and can increase fuel consumption when used frequently.
- Tunnel thrusters are less effective than azimuth units in heavy seas or for high‑speed dynamic positioning.
- Maintenance of bearings, seals and the duct liner is required to prevent wear and cavitation over time.
Typical Vessels:
Offshore supply vesselFerryMedium‑size container ship (up to ~150 m LOA)Cruise ship (mid‑range)Coastal bulk carrier
Decision Guide: Choose if the vessel needs strong bow thrust for port manoeuvring or low‑speed DP, has sufficient electrical capacity, and can accommodate a 900 mm tunnel. Avoid if space at the bow is constrained, the ship operates primarily in heavy sea states where azimuth thrusters are preferred, or power availability is limited.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
JA-TT-500 stern
unverified
· 500.0 kW
· tunnel thruster
Power (kW)
500
Thrust (kN)
60.0
Diameter (mm)
900
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (60 kN) relative to its 500 kW power rating
- Compact 900 mm tunnel diameter fits into limited stern spaces
- Robust water‑lubricated design reduces wear and maintenance intervals
- Integrated control electronics compatible with most ship bridge systems
Weaknesses
- Large tunnel opening can reduce local hull strength if not properly reinforced
- Power demand (500 kW) may be significant for vessels with limited electrical generation capacity
- Noise and vibration levels are higher than some ducted‑propeller alternatives
- Installation requires sufficient stern clearance; not suitable for very narrow aft sections
Typical Vessels:
Container ships (up to ~30 000 dwt)Cruise linersOffshore supply vesselsLNG carriersBulk carriers (mid‑size)
Decision Guide: Choose if you need reliable, high‑thrust stern maneuvering on a vessel with adequate aft space and sufficient power generation. Avoid if hull reinforcement is problematic, noise limits are strict, or the ship’s electrical system cannot support a 500 kW motor.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
JA-TT-600 bow
unverified
· 600.0 kW
· tunnel bow thruster
Power (kW)
600
Thrust (kN)
72.0
Diameter (mm)
980
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (72 kN at 600 kW) gives excellent manoeuvring capability.
- Large 980 mm duct diameter provides efficient water flow and reduced cavitation risk.
- Robust Jastram construction with low‑maintenance bearings and integrated cooling system.
- Compact tunnel housing limits hull penetration, improving structural integrity.
- Proven design widely accepted by classification societies for new‑build installations.
Weaknesses
- Large duct size requires significant bow space and may affect hull form modifications.
- 600 kW electrical demand necessitates a strong shipboard power plant and dedicated cabling.
- Installation in the bow can be complex, especially on vessels with limited internal volume.
- Higher initial cost compared with smaller or azimuth thrusters of similar power.
- Potential for increased noise/vibration if not properly isolated.
Typical Vessels:
Container shipsCruise linersOffshore supply vesselsLNG carriersLarge ferries
Decision Guide: Choose if: the vessel requires strong low‑speed thrust for port manoeuvring, dynamic positioning or emergency steering and has sufficient electrical generation capacity. Avoid if: the ship is small to medium size with limited power budget, or hull geometry cannot accommodate a near‑1 m tunnel duct without major redesign.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
JA-TT-600 stern
unverified
· 600.0 kW
· tunnel thruster
Power (kW)
600
Thrust (kN)
72.0
Diameter (mm)
980
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (72 kN) suitable for large vessel stern manoeuvring
- Large tunnel diameter (980 mm) reduces cavitation and improves efficiency
- 600 kW power rating matches modern electric propulsion standards
- Proven Jastram brand reputation for marine thruster reliability
- Compact integration at the stern aids dynamic positioning systems
Weaknesses
- Requires a ~1 m hull opening, limiting installation on vessels with restricted beam
- High power consumption increases vessel electrical load
- Maintenance of large‑diameter bearings and seals can be labour intensive
- Potential for increased noise/vibration at full power if not properly isolated
- Initial cost is higher than lower‑power tunnel thrusters
Typical Vessels:
Aframax TankerPanamax Container ShipCruise VesselOffshore Supply VesselLNG Carrier
Decision Guide: Choose if: you need >70 kN stern thrust for a vessel of 30 000‑80 000 gt, have sufficient hull space for a ~1 m tunnel, and require proven reliability for DP or tight‑dock operations. Avoid if: the ship is smaller than 15 000 gt, hull geometry cannot accommodate a large tunnel, or budget constraints favour lower‑power thrusters.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
JA-TT-750 bow
unverified
· 750.0 kW
· high‑power tunnel thruster
Power (kW)
750
Thrust (kN)
90.0
Diameter (mm)
1100
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (≈90 kN) for its size, enabling effective port entry/exit on large ships
- Compact integration within the hull reduces above‑deck clutter and wind resistance
- Robust German engineering with proven reliability and low maintenance intervals
- Integrated control electronics compatible with most ship bridge systems
- Suitable for vessels >100 000 dwt where high thrust is required
Weaknesses
- High electrical power demand (≈750 kW) increases onboard energy consumption
- Installation requires significant hull penetration and precise alignment
- Fixed‑direction thrust; less flexible than azimuth or pod thrusters for low‑speed maneuvering
- Potential cavitation at maximum thrust in shallow water conditions
- May require additional duct reinforcement on older hull structures
Typical Vessels:
Container shipsCruise linersLNG carriersBulk carriersOffshore supply vessels
Certifications:
DNV
Decision Guide: Choose if: you need a very high thrust bow thruster for a large vessel, have sufficient hull space for a 1.1 m tunnel, and prefer a proven, low‑maintenance solution over more expensive azimuth units. Avoid if: you require 360° thrust vectoring, operate primarily in shallow waters where cavitation risk is high, or need to minimise power consumption.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
JA-TT-750 stern
unverified
· 750.0 kW
· high‑power tunnel thruster
Power (kW)
750
Thrust (kN)
90.0
Diameter (mm)
1100
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (≈90 kN) suitable for large ships and DP operations
- Large 1.1 m duct diameter provides efficient water flow and reduced cavitation risk at design load
- 750 kW motor gives strong response for rapid heading changes
- Stern mounting improves aft‑end control during docking and emergency stopping
- Jastram’s proven reputation for robust marine propulsion components
Weaknesses
- High electrical power demand (≈750 kW) may require substantial generator capacity
- Large physical size needs considerable hull space and structural reinforcement
- Installation and maintenance are more complex than smaller thrusters
- Potential for increased noise and vibration at full load
- Higher initial cost compared with lower‑power tunnel units
Typical Vessels:
Crude oil tankerProduct tankerContainer ship (>150 m LOA)Cruise linerOffshore supply vesselLNG carrier
Decision Guide: Choose if the vessel requires >80 kN of stern thrust for DP2/DP3, large‑scale docking or emergency maneuvering and has sufficient generator capacity. Avoid on smaller vessels (<100 m) where power consumption and space constraints outweigh the benefit.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
JA-TT-800 bow
unverified
· 800.0 kW
· tunnel thruster
Power (kW)
800
Thrust (kN)
96.0
Diameter (mm)
1140
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (96 kN at 800 kW) enables rapid heading changes and DP support.
- Compact tunnel layout fits within standard bow sections without protruding below the hull.
- Low vibration and noise due to enclosed flow path, improving crew comfort.
- Integrated Jastram control electronics compatible with most ship‑handling systems.
- Proven track record on a range of large commercial vessels.
Weaknesses
- Large 1.14 m tunnel diameter limits installation in vessels with narrow bow sections.
- Higher power demand (800 kW) increases auxiliary load and fuel consumption.
- Maintenance requires periodic inspection of bearing housings within the tunnel.
- Installation may require hull reinforcement, adding construction cost.
- Noise at full power can be noticeable for nearby passenger areas.
Typical Vessels:
Container shipCruise linerOffshore supply vesselLNG carrierRo‑Ro ferry
Certifications:
DNVABS
Decision Guide: Choose if: you need high bow thrust for DP or tight port manoeuvring on a large vessel and have sufficient hull space for a 1.14 m tunnel. Avoid if: the ship’s draft or bow geometry cannot accommodate the tunnel diameter, or auxiliary power is severely limited.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
JA-TT-800 stern
unverified
· 800.0 kW
· tunnel thruster
Power (kW)
800
Thrust (kN)
96.0
Diameter (mm)
1140
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (96 kN) from an 800 kW motor enables rapid lateral movement in tight ports.
- Large 1.14 m tunnel diameter provides efficient water flow and reduced cavitation risk at high loads.
- Robust Jastram engineering with proven reliability on long‑haul vessels.
- Integrated stern installation minimizes above‑deck clutter and protects the unit from impact damage.
Weaknesses
- Large hull penetration required; may limit retro‑fit options on existing ships.
- High power demand (800 kW) increases fuel consumption of auxiliary generators.
- Maintenance access can be difficult in confined stern spaces.
- Potential for increased noise and vibration compared with smaller thrusters.
Typical Vessels:
Very Large Crude Carrier (VLCC)Ultra‑Large Container Ship (ULCS)Cruise shipOffshore supply vesselRo‑Ro ferry
Decision Guide: Choose if: you need a high‑thrust stern thruster for vessels >30 000 gt, have sufficient stern space for a 1.14 m tunnel, and require proven reliability for frequent port calls or DP support. Avoid if: the vessel is small to medium size, power budget is limited, or an azimuth (azipod) system would better suit dynamic positioning requirements.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
JA-TT-1000 bow
unverified
· 1000.0 kW
· tunnel thruster
Power (kW)
1000
Thrust (kN)
120.0
Diameter (mm)
1300
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust output (120 kN) suitable for precise bow handling on large ships
- Large 1.3 m duct diameter reduces cavitation and improves efficiency at high power levels
- Robust tunnel housing protects the propeller from debris and grounding impacts
- Integrated bow location provides optimal leverage for docking and DP maneuvers
- Designed for 1 000 kW drive units, compatible with common VFD systems
Weaknesses
- Large physical size limits installation to vessels with sufficient hull space
- High power demand (1 MW) increases fuel consumption and may require upgraded electrical supply
- Heavier overall unit weight can complicate retro‑fit projects
- Installation and maintenance access are more demanding due to the large tunnel geometry
- Higher upfront cost compared with lower‑power thruster options
Typical Vessels:
Container shipCrude oil tankerLNG carrierCruise linerOffshore supply vesselIce‑class bulk carrier
Decision Guide: Choose if the vessel requires >100 kN bow thrust for tight port maneuvering, dynamic positioning or ice navigation and has sufficient hull space and power generation capacity. Avoid if the ship is size‑restricted, power‑limited, or budget‑constrained where a smaller thruster would meet operational needs.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
JA-TT-1000 stern
unverified
· 1000.0 kW
· Tunnel thruster
Power (kW)
1000
Thrust (kN)
120.0
Diameter (mm)
1300
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust output (120 kN) suitable for large vessels and DP operations
- Large tunnel diameter reduces cavitation risk at full power
- Integrated stern installation minimizes hull penetration points
- Robust construction typical of Jastram Marine, designed for heavy‑duty service
- Provides precise low‑speed thrust vectoring for tight berthing
Weaknesses
- High electrical power demand (1 MW) may strain ship’s power plant
- Large tunnel size can affect hull structural integrity if not properly reinforced
- Maintenance requires dry‑docking or extensive access arrangements
- Effectiveness drops sharply at higher vessel speeds
- Potential for water ingress if seals deteriorate, requiring regular inspection
Typical Vessels:
VLCC / Suezmax TankerLarge Container Ship (≥10 000 TEU)Cruise ShipOffshore Supply Vessel with DPLNG Carrier
Decision Guide: Choose if: the vessel requires strong stern thrust for dynamic positioning, tight port manoeuvring, or emergency stopping on ships >150 000 DWT. Avoid if: power generation capacity is limited, vessel size is small (<30 000 DWT), or azimuth thrusters are preferred for 360° thrust capability.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
JA-TT-1200 bow
unverified
· 1200.0 kW
· tunnel thruster
Power (kW)
1200
Thrust (kN)
144.0
Diameter (mm)
1460
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (144 kN) from 1200 kW gives strong manoeuvring capability on large vessels
- Large tunnel diameter (1460 mm) reduces cavitation and improves efficiency
- Integrated tunnel design minimises hull penetration points and simplifies installation
- Robust steel construction suitable for harsh marine environments
- Provides reliable low‑speed thrust for dynamic positioning and tight docking
Weaknesses
- Significant bow space required to accommodate the 1.46 m tunnel diameter
- High power consumption increases fuel use and may need dedicated cooling systems
- Installation complexity can raise dry‑dock time and cost
- Higher upfront cost compared with smaller or azimuth thrusters for similar thrust levels
- Weight and structural reinforcement requirements add to overall vessel weight budget
Typical Vessels:
Container shipCrude oil tankerLNG carrierCruise linerOffshore supply vessel
Decision Guide: Choose if: you need high bow thrust for large vessels, have sufficient bow space for a 1.46 m tunnel, and require low cavitation for DP or tight port manoeuvring. Avoid if: the vessel is small, space‑constrained, or budget‑sensitive where a smaller azimuth unit would suffice.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
JA-TT-1200 stern
unverified
· 1200.0 kW
· tunnel stern thruster
Power (kW)
1200
Thrust (kN)
144.0
Diameter (mm)
1460
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (144 kN) for its power class, enabling strong lateral forces in DP operations
- Large 1460 mm duct diameter reduces cavitation and improves efficiency at low speeds
- Robust Jastram modular construction simplifies installation and future upgrades
- Integrated control electronics compatible with most ship‑board DP systems
Weaknesses
- Large physical size requires substantial hull penetration and may limit use on smaller vessels
- High power demand (1200 kW) increases fuel consumption and electrical load
- Weight and mounting loads are significant; structural reinforcement is often required
- Spare‑part logistics can be longer outside Jastram’s primary service regions
Typical Vessels:
LNG carrierCruise shipOffshore supply vesselContainer ship (>30 000 dwt)Bulk carrier (large class)
Decision Guide: Choose if the vessel requires high lateral thrust for DP2/DP3 operations, tight port manoeuvring or emergency backup on a large hull. Avoid if the ship’s power plant cannot accommodate a 1200 kW load, or if space and structural constraints prevent installation of a 1.46‑m duct.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
JA-TT-1500 bow
unverified
· 1500.0 kW
· tunnel bow thruster
Power (kW)
1500
Thrust (kN)
180.0
Diameter (mm)
1700
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (180 kN) suitable for large ships and DP operations
- Large 1.7 m tunnel diameter reduces cavitation and improves efficiency
- Robust steel housing and marine‑grade bearings for long service life
- Integrated control electronics compatible with common bridge systems
- Proven design from Jastram, a specialist in high‑power thrusters
Weaknesses
- 1500 kW power demand requires substantial electrical supply capacity
- Large tunnel size limits installation to vessels with sufficient bow space
- Hull penetration and structural reinforcement increase construction cost
- Maintenance of seals and bearings can be intensive on heavily used units
- Weight of the unit may affect vessel weight distribution and stability
Typical Vessels:
Container ship (≥8,000 TEU)Cruise linerLNG carrierBulk carrier (>150 kt)Offshore supply vessel
Decision Guide: Choose if you need high thrust for safe docking, port entry/exit or dynamic positioning of large vessels and have adequate electrical power and bow space. Avoid if the ship’s power plant cannot support 1.5 MW dedicated to a thruster, or if hull geometry restricts installation of a 1.7 m tunnel.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
JA-TT-1500 stern
unverified
· 1500.0 kW
· tunnel thruster
Power (kW)
1500
Thrust (kN)
180.0
Diameter (mm)
1700
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (180 kN) relative to power rating (1500 kW)
- Large 1.7 m tunnel diameter helps minimise cavitation and improve efficiency
- Designed for stern installation, providing effective aft‑side maneuverability on large ships
Weaknesses
- Requires substantial hull penetration and reinforcement due to its size
- High electrical power demand (1500 kW) may limit suitability on vessels with limited generator capacity
- Large physical footprint can restrict use on smaller or space‑constrained hull forms
Typical Vessels:
Container shipTankerBulk carrierCruise shipOffshore supply vessel
Decision Guide: Choose if: you need a high‑thrust stern thruster for vessels >30,000 gt that perform frequent port entries, dynamic positioning or require strong aft maneuverability. Avoid if: the vessel has limited electrical generation capacity, restricted hull space at the stern, or only modest manoeuvring assistance is required.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
JA-TT-2000 bow
unverified
· 2000.0 kW
· tunnel bow thruster
Power (kW)
2000
Thrust (kN)
240.0
Diameter (mm)
2100
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high static thrust (240 kN) suitable for large vessels and DP operations
- Large 2100 mm tunnel diameter reduces cavitation and improves efficiency
- Robust, low‑maintenance design with no external moving parts
- Integrated Jastram control system compatible with most ship automation suites
- Proven track record of reliability in commercial fleets
Weaknesses
- Large physical size limits installation on vessels with restricted bow space
- High power demand (2 000 kW) increases fuel consumption and electrical load
- Fixed‑direction thrust; cannot provide full 360° vectoring like azimuth units
- Requires substantial structural reinforcement of the hull opening
- Potential for higher acoustic signature compared to smaller thrusters
Typical Vessels:
Container shipCruise linerLNG carrierOffshore supply vesselHeavy‑lift / project cargo ship
Certifications:
IMO Type ApprovalDNV Class (DNVGL) approval
Decision Guide: Choose if you need very high bow thrust for large vessels, DP2/3 capability, and prefer a simple, low‑maintenance tunnel design. Avoid if hull space is limited, you require full 360° thrust vectoring, or want to minimise power consumption.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
JA-TT-2000 stern
unverified
· 2000.0 kW
· tunnel thruster
Power (kW)
2000
Thrust (kN)
240.0
Diameter (mm)
2100
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (240 kN) suitable for DP2 and tight port manoeuvring
- Compact 2100 mm tunnel diameter fits into many hull forms without excessive structural penalty
- Integrated water‑cooling system allows continuous operation at full power
- Balanced impeller design reduces vibration and bearing wear
- Jastram’s remote monitoring/control package simplifies integration with ship automation
Weaknesses
- High electrical demand (2 MW) increases fuel consumption for auxiliary generators
- Large duct may require hull reinforcement during retrofit installations
- Noise level at full power can be significant, requiring additional acoustic mitigation
- Spare‑part logistics are limited to Jastram’s dealer network in some regions
- Requires dedicated cooling water circuit and associated piping
Typical Vessels:
Ultra‑large container shipsCrude oil tankers (VLCC/MR)LNG carriersCruise linersOffshore supply vessels with DP2 requirements
Certifications:
IMO Type ApprovalDNV GL Class
Decision Guide: Choose if the vessel needs high thrust for dynamic positioning, tight‑berth entry or limited bow‑thruster space and can accommodate the auxiliary power and cooling requirements. Avoid if the ship is small to medium size, has strict noise limits, or cannot support the additional electrical load.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
JA-TT-2500 bow
unverified
· 2500.0 kW
· high‑power tunnel thruster
Power (kW)
2500
Thrust (kN)
300.0
Diameter (mm)
2500
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (300 kN) suitable for mega‑vessels and tight berthing situations
- Compact duct size relative to thrust output, allowing installation in limited hull space
- Modular design simplifies integration and future upgrades
- Robust cooling system handles the 2 500 kW power rating with minimal overheating risk
- Proven Jastram Marine engineering reputation for durability in harsh marine environments
Weaknesses
- Large hull penetration (2.5 m duct) may require extensive structural reinforcement
- High electrical/hydraulic power demand increases onboard energy consumption
- Installation and maintenance access can be challenging due to size and location
- Acoustic noise levels are higher than smaller thrusters, potentially affecting crew comfort
- Initial capital cost is significant compared with lower‑power alternatives
Typical Vessels:
Cruise shipLNG carrierOffshore supply vesselLarge container shipRo‑Ro ferry
Decision Guide: Choose if: the vessel requires very high bow thrust for safe berthing in confined ports, has sufficient power generation capacity, and can accommodate a 2.5 m tunnel duct. Avoid if: the ship is small to medium size, power budget is limited, or hull design cannot support a large tunnel penetration without major modifications.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
JA-TT-2500 stern
unverified
· 2500.0 kW
· tunnel thruster
Power (kW)
2500
Thrust (kN)
300.0
Diameter (mm)
2500
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output of 300 kN enables precise stern maneuvering on large ships
- Large 2.5 m tunnel diameter provides efficient water flow and reduces cavitation risk
- Integrated 2500 kW motor simplifies installation and maintenance
- Stern placement improves astern docking, dynamic positioning and emergency backup capability
Weaknesses
- Physical size requires substantial hull penetration and structural reinforcement
- High power demand (2500 kW) increases vessel electrical load and fuel consumption
- Not suitable for smaller vessels or ships with limited stern space
- Tunnel geometry can be less effective in very shallow water due to draft constraints
Typical Vessels:
Very Large Crude Carrier (VLCC)Aframax TankerContainer Ship (>10,000 TEU)Bulk Carrier (>150,000 dwt)Cruise Ship
Decision Guide: Choose if the vessel requires a high‑power stern thruster for tight port maneuvers, dynamic positioning or emergency backup on ships larger than about 80 000 dwt. Avoid if the ship’s size, power budget or hull design cannot accommodate a 2.5 m tunnel and 2500 kW motor.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
JA-TT-3000 bow
unverified
· 3000.0 kW
· tunnel thruster
Power (kW)
3000
Thrust (kN)
360.0
Diameter (mm)
2900
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust output (360 kN) suitable for large ships and DP operations
- Large 2.9 m duct diameter improves hydraulic efficiency and reduces slip loss
- Compact bow‑mounting minimizes deck space usage compared with azimuth pods
- Robust tunnel construction offers good protection against debris and grounding impacts
Weaknesses
- High power demand (3 MW) requires substantial shipboard electrical generation capacity
- Large hull penetration may increase structural complexity and cost of installation
- Potential for cavitation at full‑load conditions, requiring careful propeller design
- Maintenance access to the internal impeller can be more involved than with external azimuth units
Typical Vessels:
Container ship (≥8 000 TEU)Cruise linerLNG carrierOffshore supply vesselLarge bulk carrier
Decision Guide: Choose if the vessel needs high bow thrust for precise docking, dynamic positioning or maneuvering in confined ports and has sufficient power generation capacity. Avoid on smaller ships where the 3 MW rating is oversized or where hull modifications for a large tunnel are impractical.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
JA-TT-3000 stern
unverified
· 3000.0 kW
· high‑power tunnel thruster
Power (kW)
3000
Thrust (kN)
360.0
Diameter (mm)
2900
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (≈360 kN) suitable for mega‑size tankers and bulk carriers
- Robust tunnel design tolerates harsh sea‑water environments
- Integrated with Jastram’s proprietary blade geometry for improved efficiency at low speeds
- Standard 2,900 mm duct diameter fits common stern thruster tunnels on new builds
Weaknesses
- High electrical power demand (≈3 MW) requiring substantial onboard generation capacity
- Large tunnel aperture may reduce hull strength if not properly reinforced
- Potential for cavitation at high RPMs, increasing blade wear
- Maintenance access can be limited in confined stern spaces
Typical Vessels:
Very Large Crude Carrier (VLCC)Ultra‑Large Container Ship (ULCS)Capesize Bulk CarrierOffshore Support Vessel (OSV) with high manoeuvring requirements
Decision Guide: Choose if: you need maximum stern thrust for vessels >200 m LOA, have sufficient onboard power generation and require reliable low‑speed positioning in tight ports. Avoid if: vessel power plant is limited, hull space cannot accommodate a 2.9 m tunnel, or operational profile does not demand extreme manoeuvring capability.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
JA-TT-3500 bow
unverified
· 3500.0 kW
· tunnel thruster
Power (kW)
3500
Thrust (kN)
420.0
Diameter (mm)
3300
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (420 kN) suitable for large vessels and tight berths
- Compact installation within the hull, preserving deck space
- Integrated duct reduces propeller exposure to debris
- High power rating (3.5 MW) provides strong manoeuvring force even in adverse conditions
Weaknesses
- Large diameter (3.3 m) requires significant hull penetration and structural reinforcement
- Higher installation cost compared with smaller azimuth thrusters
- Potential for cavitation at high RPMs, requiring careful blade design and monitoring
- Fixed direction; cannot rotate like a pod or azimuth unit
Typical Vessels:
Large container ships (>200 m)Crude oil and product tankersLNG carriersCruise linersOffshore supply vessels with high‑power DP requirements
Decision Guide: Choose if the vessel needs very high bow thrust for safe docking in confined ports, dynamic positioning support, or when deck space is at a premium and a fixed‑direction thruster is acceptable. Avoid if hull modifications are prohibitive, the required thrust is modest, or a steerable azimuth unit would provide greater flexibility.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
JA-TT-3500 stern
unverified
· 3500.0 kW
· Tunnel thruster
Power (kW)
3500
Thrust (kN)
420.0
Diameter (mm)
3300
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (420 kN) relative to power, enabling rapid lateral movement of large ships
- Large 3.3 m tunnel diameter reduces cavitation and improves efficiency at high load
- Robust stainless‑steel housing designed for harsh marine environments
- Integrated control electronics compatible with most bridge automation systems
- Proven Jastram design reputation for reliability and long service intervals
Weaknesses
- High electrical power demand (3.5 MW) requires substantial onboard generation capacity
- Large tunnel footprint can limit hull form options and may require structural reinforcement
- Installation and alignment are complex, often needing dry‑dock time
- Maintenance access to the impeller is more restricted than in azimuth or pull‑type units
- Capital cost is higher than smaller thrusters of comparable power
Typical Vessels:
Very Large Crude Carrier (VLCC)Ultra‑Large Container Vessel (ULCV)Panamax and Post‑Panamax Bulk CarriersLNG carriersCruise ships over 150 000 GT
Decision Guide: Choose the JA‑TT‑3500 when a vessel >150 k DWT needs high lateral thrust for tight berthing, DP support or emergency manoeuvring and has sufficient electrical generation capacity. Avoid if hull space is limited, the ship’s power plant cannot supply ~3.5 MW continuously, or budget constraints preclude a large tunnel thruster.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
JA-TT-4000 bow
unverified
· 4000.0 kW
· high-power tunnel thruster
Power (kW)
4000
Thrust (kN)
480.0
Diameter (mm)
3700
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Provides very high thrust (≈480 kN) suitable for precise low‑speed maneuvering of large ships.
- Large 3700 mm tunnel diameter enables high water flow and efficient thrust generation.
- 4000 kW power rating matches the requirements of vessels with substantial displacement and limited berth space.
Weaknesses
- Physical size (3.7 m tunnel) limits installation to hulls with sufficient bow volume; not suitable for smaller ships.
- High electrical power demand (4 MW) may require upgraded shipboard power distribution systems.
- Potentially higher acoustic signature compared with smaller or duct‑less thrusters.
Decision Guide: Choose the JA‑TT‑4000 when a vessel needs ≥480 kN bow thrust for tight port manoeuvring and has adequate bow space and power supply. Avoid it on smaller vessels or where weight, volume, or power constraints are critical.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
JA-TT-4000 stern
unverified
· 4000.0 kW
· tunnel thruster
Power (kW)
4000
Thrust (kN)
480.0
Diameter (mm)
3700
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (≈480 kN) suitable for mega‑vessels and dynamic positioning
- Compact tunnel layout saves deck space compared with azimuth units of similar power
- Robust, low‑maintenance steel housing proven in harsh offshore environments
- Integrated control electronics compatible with most ship automation systems
- Low acoustic signature – useful for noise‑sensitive vessels such as cruise ships
Weaknesses
- High electrical demand (≈4 MW) requires substantial onboard power generation capacity
- Large hull penetration; installation is complex and may affect structural integrity
- Fixed thrust direction limits maneuverability compared with azimuth or pod thrusters
- Weight and size can be a constraint on vessels with limited stern space
- Maintenance of the tunnel lining and bearing system can be labour‑intensive
Typical Vessels:
LNG CarrierCruise ShipOffshore Supply VesselFPSO / FSOLarge Container or Bulk Carrier (for DP‑assisted berthing)
Decision Guide: Choose if: you need very high stern thrust for a large vessel, have sufficient power generation capacity, and prefer a proven, low‑maintenance solution with minimal deck clutter. Avoid if: space for a large tunnel is limited, you require 360° thrust vectoring, or the vessel’s power plant cannot support a 4 MW electric load.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
JA-TT-4500 bow
unverified
· 4500.0 kW
· high‑power tunnel thruster
Power (kW)
4500
Thrust (kN)
540.0
Diameter (mm)
4100
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (540 kN) enables rapid lateral movement of ultra‑large ships.
- Large 4.1 m tunnel diameter reduces cavitation and improves hydraulic efficiency.
- Robust Jastram construction rated for harsh marine environments and extended service intervals.
- Integrated control interface compatible with most DP and bridge navigation systems.
Weaknesses
- High electrical power demand (≈4.5 MW) requires substantial onboard generation capacity.
- Physical size and weight demand significant hull penetration and structural reinforcement.
- Installation and maintenance are complex due to the large tunnel geometry.
- Higher capital cost compared with smaller thrusters or azimuth pods for similar thrust.
Typical Vessels:
VLCC / ULCC tankerLNG carrierOffshore supply vessel (DP2/DP3)Cruise shipLarge container vessel
Decision Guide: Choose if the vessel needs maximum bow thrust for port entry of very large ships, dynamic positioning on offshore rigs, or rapid docking maneuvers. Avoid if the ship’s power plant cannot support a 4.5 MW thruster, hull space is limited, or budget constraints favor smaller or azimuth‑type solutions.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
JA-TT-4500 stern
unverified
· 4500.0 kW
· high‑power tunnel thruster
Power (kW)
4500
Thrust (kN)
540.0
Diameter (mm)
4100
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (540 kN) suitable for large tankers and container ships
- Large 4100 mm duct diameter reduces cavitation and improves efficiency
- Optimised stern placement enhances yaw control during docking and DP operations
- Robust construction typical of Jastram Marine for long service intervals
- Integrated control interface compatible with most ship‑board DP systems
Weaknesses
- Large physical size limits installation on smaller hulls or retrofits
- High power demand (4.5 MW) requires substantial electrical/hydraulic supply infrastructure
- Increased maintenance complexity due to larger bearings and seals
- Potential for higher acoustic noise and vibration at full power
- Higher upfront cost compared with lower‑power thruster alternatives
Typical Vessels:
VLCC / ULCC tankerLarge container ship (≥10,000 TEU)LNG carrierOffshore supply vessel (DP2/3)Cruise liner
Decision Guide: Choose if: you need maximum thrust for a very large vessel, require DP‑2/DP‑3 capability, and have sufficient space and power plant capacity. Avoid if: the ship’s hull form or available stern volume cannot accommodate a 4.1 m duct, or if lower thrust levels would meet maneuverability needs at reduced cost.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
JA-TT-5000 bow
unverified
· 5000.0 kW
· tunnel bow thruster
Power (kW)
5000
Thrust (kN)
600.0
Diameter (mm)
4500
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (≈600 kN) suitable for mega vessels and tight berths
- Integrated water‑lubricated tunnel reduces acoustic signature compared with external propellers
- Robust steel housing designed for harsh marine environments and heavy duty cycles
- Direct drive configuration enables precise thrust vectoring via advanced control systems
Weaknesses
- Large tunnel diameter (4.5 m) limits installation to vessels with ample hull space
- High electrical power demand (≈5 MW) requires substantial onboard generation capacity
- Maintenance access can be challenging due to size and location within the bow structure
- Potential for cavitation at very high load if not matched with proper inlet design
Typical Vessels:
Cruise shipLNG carrierLarge container vesselBulk carrier (≥200 kt)Offshore supply vessel
Decision Guide: Choose if the vessel requires exceptional low‑speed maneuverability, has sufficient hull volume for a 4.5 m tunnel, and can provide the necessary electrical power. Avoid on smaller ships or where space constraints make installation impractical.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
JA-TT-5000 stern
unverified
· 5000.0 kW
· electric tunnel thruster
Power (kW)
5000
Thrust (kN)
600.0
Diameter (mm)
4500
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (600 kN) suitable for large ships and DP operations
- Large 4.5 m duct reduces cavitation and improves efficiency at high power
- Integrated control electronics compatible with modern bridge systems
- Robust steel construction typical of Jastram’s marine‑grade products
- Designed for continuous operation, supporting dynamic positioning
Weaknesses
- Large physical size limits installation to vessels with sufficient stern space
- High electrical power demand (5 MW) requires substantial shipboard generation capacity
- Installation and commissioning are complex and costly
- Maintenance of large bearings and seals can be intensive
- Weight and structural loads may require hull reinforcement
Typical Vessels:
Cruise shipsLNG carriersVery Large Container Vessels (VLCC)Bulk carriers >200 kDWTOffshore support vessels with DP
Decision Guide: Choose if the vessel needs a powerful stern thruster for precise low‑speed maneuvering, dynamic positioning or emergency stop capability and has sufficient electrical generation capacity. Avoid if the ship’s stern space is limited, power supply cannot meet 5 MW demand, or budget constraints preclude the higher installation cost.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Schottel
39 ✓ 13 verified
Schottel STT Thruster 100kW bow
unverified
· 100.0 kW
· Tunnel thruster
Power (kW)
100
Thrust (kN)
12.0
Diameter (mm)
580
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (≈12 kN at 100 kW) for its size
- Modular design simplifies installation and replacement
- Proven Schottel reliability with low cavitation risk
- Integrated control electronics compatible with most bridge systems
- Relatively shallow duct depth suitable for vessels with limited draft
Weaknesses
- Limited maximum thrust compared with larger azimuth thrusters
- Tunnel geometry can be prone to fouling and requires regular cleaning
- Noise and vibration levels higher than some propeller‑type bow thrusters
- Not ideal for vessels requiring high‑power DP (>15 kN thrust)
- Performance drops in very shallow water where duct ventilation is restricted
Typical Vessels:
Offshore Supply Vessel (OSV)Crew Transfer VesselCoastal Bulk CarrierSmall Container FeederCoastal TankerFerry
Certifications:
DNV
Decision Guide: Choose if: you need a compact, reliable bow thruster delivering ~12 kN for vessels up to ~2 000 GT with limited hull space and moderate DP requirements. Avoid if: the vessel demands higher thrust (>15 kN), operates in very shallow water where duct ventilation is critical, or requires full‑azimuth propulsion for high‑precision dynamic positioning.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
Schottel STT Thruster 100kW stern
unverified
· 100.0 kW
· integrated tunnel thruster
Power (kW)
100
Thrust (kN)
12.0
Diameter (mm)
580
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (≈12 kN at 100 kW)
- Sealed motor reduces maintenance and corrosion risk
- Compact tunnel design fits limited hull space
- Low cavitation and noise levels for crew comfort
- Modular mounting allows quick installation and replacement
Weaknesses
- Limited maximum thrust may be insufficient for large vessels or high‑power DP requirements
- Tunnel geometry can cause hull vibration if not properly aligned
- Power limited to 100 kW, restricting use on higher‑speed ships
- Hull penetration required, adding structural complexity
- Fixed‑pitch propeller version offers less flexibility than controllable‑pitch options
Typical Vessels:
Offshore supply vesselWorkboat / Utility boatFerryCoastal tankerContainer feeder (small)Tug (auxiliary)
Decision Guide: Choose if: you need a compact stern thruster for vessels up to ~200 m LOA with modest power budgets, require low maintenance and good maneuverability for docking or DP‑1 operations. Avoid if: the vessel demands higher thrust (>15 kN), operates in high‑speed service, or has strict vibration constraints that exceed tunnel‑thruster limits.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Schottel STT Thruster 200kW bow
unverified
· 200.0 kW
· tunnel thruster
Power (kW)
200
Thrust (kN)
24.0
Diameter (mm)
660
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Compact 660 mm tunnel diameter fits tight hull spaces
- Integrated Schottel control system simplifies operation and monitoring
- Proven reliability with long service intervals and easy maintenance
- High thrust‑to‑power ratio for a tunnel thruster of this size
- Corrosion‑resistant stainless‑steel housing suitable for marine environments
Weaknesses
- Maximum thrust limited to ~24 kN, may be insufficient for larger vessels or high‑wind conditions
- Higher noise and vibration compared with azimuth thrusters
- Requires hull penetration and internal ducting, increasing installation complexity
- Potential cavitation at high RPM in shallow water
- Limited thrust reserve for demanding dynamic positioning tasks
Typical Vessels:
Offshore Supply VesselContainer FeederRo‑Ro FerrySmall Bulk CarrierCruise Ship (mid‑size)
Decision Guide: Choose if: you need a compact, low‑maintenance bow thruster with up to ~24 kN thrust for vessels up to about 30,000 dwt where hull space is limited and reliable maneuvering in ports is required. Avoid if: higher thrust (>30 kN) or full azimuth capability is needed for heavy dynamic positioning, or if noise/vibration must be minimised.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Schottel STT Thruster 200kW stern
unverified
· 200.0 kW
· tunnel thruster
Power (kW)
200
Thrust (kN)
24.0
Diameter (mm)
660
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (≈0.12 kN per kW) for efficient manoeuvring
- Compact 660 mm tunnel fits vessels with limited hull space
- Integrated control system compatible with most ship automation suites
- Schottel’s global service network ensures rapid spare‑part supply and support
Weaknesses
- Maximum thrust of 24 kN may be insufficient for large tankers or high‑power DP vessels
- Installation requires a dedicated stern tunnel, reducing available cargo space
- Requires connection to the ship’s cooling‑water system and dedicated power cabling
- Higher upfront cost compared with generic low‑spec thrusters
Typical Vessels:
Offshore supply vesselPlatform support vesselFerryCoastal container or bulk carrier (up to ~30 000 dwt)Workboat / tug (light duty)
Decision Guide: Choose if: you need a reliable, compact thruster delivering up to 24 kN for vessels up to medium size where space is limited and precise low‑speed control is required. Avoid if: the vessel demands higher thrust (>30 kN), has severe weight or space constraints that preclude a 660 mm tunnel, or budget constraints favour a lower‑spec unit.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Schottel STT Thruster 300kW bow
unverified
· 300.0 kW
· Schottel Tunnel Thruster
Power (kW)
300
Thrust (kN)
36.0
Diameter (mm)
740
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (36 kN at 300 kW) for compact bow installations
- Proven Schottel reliability with low vibration and easy maintenance access
- Integrated control electronics compatible with most ship bridge systems
- Compact tunnel diameter (740 mm) minimises hull penetration
- Suitable for vessels requiring DP‑1 or DP‑2 assistance
Weaknesses
- Maximum thrust may be insufficient for very large ships or high‑wind conditions
- Tunnel geometry can cause increased resistance when the vessel is underway
- Higher initial cost compared with basic single‑propeller bow thrusters
- Potential cavitation at high blade angles if not properly tuned
- Limited azimuth capability – only provides lateral thrust
Typical Vessels:
Offshore Supply VesselFerryCruise Ship (up to ~10,000 GT)Container Ship (up to ~15,000 DWT)Bulk Carrier (mid‑size)
Decision Guide: Choose if: you need a compact, high‑efficiency bow thruster for vessels up to medium size that require precise low‑speed handling or DP assistance. Avoid if: the vessel demands higher thrust than 36 kN, prefers full azimuth propulsion, or has severe space constraints that preclude a 740 mm tunnel.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Schottel STT Thruster 300kW stern
unverified
· 300.0 kW
· tunnel thruster
Power (kW)
300
Thrust (kN)
36.0
Diameter (mm)
740
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (36 kN at 300 kW) for its size
- Compact 740 mm tunnel fits into limited stern spaces
- Proven Schottel reliability with modular, easy‑maintenance design
- Low cavitation and noise levels compared with larger azimuth units
- Integrated control interface compatible with most DP systems
Weaknesses
- Maximum thrust may be insufficient for very large vessels or high‑power DP requirements
- Installation requires a stern tunnel cut‑out, increasing dry‑dock time
- Duct fouling can reduce efficiency if not cleaned regularly
- Higher upfront cost than basic fixed‑pitch thrusters of similar power
- Noise and vibration rise noticeably at full‑power operation
Typical Vessels:
Offshore support vesselCruise ship (up to ~150 m LOA)Container ship (up to ~30 kt)LNG carrier (mid‑size)DP2/DP3 equipped vessels
Certifications:
DNVIMO Type Approval
Decision Guide: Choose if you need a high‑thrust, space‑efficient stern thruster for precise manoeuvring or DP on medium‑size ships and offshore vessels. Avoid if the vessel requires thrust well above 40 kN, has severe budget constraints, or cannot accommodate a tunnel duct in the stern.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Schottel STT Thruster 400kW bow
unverified
· 400.0 kW
· tunnel thruster
Power (kW)
400
Thrust (kN)
48.0
Diameter (mm)
820
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (48 kN at 400 kW) for efficient maneuvering
- Integrated motor reduces installation time and eliminates separate gearbox
- Robust steel housing tolerates harsh marine environments and offers long service life
- Low vibration and noise due to direct drive design
- Proven reliability with many vessels in operation worldwide
Weaknesses
- Requires sufficient hull draft for the tunnel, limiting use on very shallow‑draft ships
- Fixed propeller direction limits azimuthal thrust capability needed for DP operations
- Potential cavitation at high RPMs if not properly sized to vessel speed profile
- Weight of the unit can be significant compared with lightweight azimuth pods
- Limited maximum thrust may be insufficient for very large vessels (>30 000 DWT)
Typical Vessels:
Handymax Bulk CarrierSmall to Medium Tanker (up to ~30 000 DWT)Offshore Supply VesselContainer FeederCruise Ship (mid‑size) for port assistance
Certifications:
DNV
Decision Guide: Choose if you need a reliable, space‑efficient bow thruster with high thrust for vessels up to medium size and have adequate hull draft. Avoid if the vessel requires full azimuthal thrust for dynamic positioning, operates in very shallow water, or needs higher total thrust than 48 kN.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Schottel STT Thruster 400kW stern
unverified
· 400.0 kW
· tunnel thruster
Power (kW)
400
Thrust (kN)
48.0
Diameter (mm)
820
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (48 kN at 400 kW) for its size class
- Robust stainless‑steel duct and propeller reduces corrosion in harsh marine environments
- Integrated Schottel control system allows precise, low‑noise steering
- Modular mounting simplifies installation on existing stern structures
- Proven reliability with extensive service history in offshore and work vessels
Weaknesses
- Limited thrust compared with larger azimuth or pod thrusters for high‑power DP applications
- Stern placement can be affected by hull flow disturbances, reducing efficiency at certain speeds
- Requires dedicated cooling water supply and regular bearing lubrication
- Noise and vibration increase noticeably at full power, which may affect passenger comfort on cruise tenders
- Maximum duct diameter (820 mm) restricts retro‑fit in vessels with limited stern space
Typical Vessels:
Offshore Supply VesselTugboatFerry / Passenger TenderWorkboatSmall Container Ship
Certifications:
DNVABS
Decision Guide: Choose if: you need a reliable, compact stern thruster delivering up to 48 kN for vessels under ~5,000 gt with moderate DP or manoeuvring requirements and prefer proven class approvals. Avoid if: the vessel requires higher thrust levels, full‑time dynamic positioning at high power, or has severe space constraints that preclude a 820 mm duct.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Schottel STT Thruster 500kW bow
unverified
· 500.0 kW
· Tunnel thruster
Power (kW)
500
Thrust (kN)
60.0
Diameter (mm)
900
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (≈60 kN at 500 kW) for a relatively small installation envelope
- Robust ducted design with low cavitation risk, suitable for continuous low‑speed operation
- Modular construction allows quick installation and straightforward maintenance access
- Integrated Schottel control system provides precise thrust vectoring and feedback to ship bridge systems
- Proven track record on a wide range of vessel classes, backed by extensive service network
Weaknesses
- Fixed‑direction duct limits effectiveness at higher speeds compared with azimuth thrusters
- Diameter (≈900 mm) may restrict installation in vessels with limited hull space or shallow tunnel depth
- Higher initial cost than basic open‑propeller bow thrusters of similar power
- Maintenance requires removal of the duct for full propeller inspection, adding downtime
- Noise and vibration levels are higher than some newer low‑speed screw designs
Typical Vessels:
Handymax bulk carrierMedium‑size product tankerOffshore supply vessel (OSV)Ferry / Ro‑RoContainer feeder
Certifications:
DNV GL Class approvalABS classification approval
Decision Guide: Choose if: you need a reliable, high‑thrust bow thruster for vessels up to ~30 000 gt with limited hull space and require proven class approvals. Avoid if: the vessel operates at higher speeds where azimuth or podded thrusters give better efficiency, or if budget constraints favour a simpler open‑propeller unit.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Schottel STT Thruster 500kW stern
unverified
· 500.0 kW
· integrated electric motor tunnel thruster
Power (kW)
500
Thrust (kN)
60.0
Diameter (mm)
900
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (≈60 kN at 500 kW)
- Compact 900 mm duct fits in medium‑size hulls
- Integrated motor reduces installation time and eliminates separate gearbox
- Proven Schottel reliability with long service history
- Low noise and vibration compared with conventional shaft‑driven thrusters
Weaknesses
- Fixed thrust direction – cannot rotate like an azimuth unit
- Duct penetration requires hull reinforcement, increasing construction cost
- Performance can degrade in very shallow water due to cavitation risk
- Maximum power limited to 500 kW; not suitable for large vessels needing >1000 kN thrust
- Maintenance access confined within the tunnel duct
Typical Vessels:
Handymax bulk carrierProduct tanker (≤30,000 DWT)Offshore supply vesselCruise ship auxiliary thrusterContainer feeder
Certifications:
DNV GL class approvalABS classification
Decision Guide: Choose if the vessel requires strong, reliable stern maneuvering in confined ports, has limited hull space for a compact duct, and benefits from an integrated motor layout. Avoid if you need 360° thrust capability, higher than 500 kW power, or operate primarily in very shallow water where cavitation is critical.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Schottel STT Thruster 600kW bow
unverified
· 600.0 kW
· tunnel thruster
Power (kW)
600
Thrust (kN)
72.0
Diameter (mm)
980
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (≈0.12 kN/kW) for its size
- Proven Schottel reliability with over 30 years in service
- Compact tunnel diameter (≈980 mm) fits medium‑size vessels
- Low vibration and easy access for routine maintenance
- Integrated control system compatible with most DP packages
Weaknesses
- Maximum thrust limited to ~72 kN – may be insufficient for very large ships or high‑wind conditions
- Installation requires a sizable hull opening, affecting structural layout
- Potential cavitation noise at full load in shallow water
- Higher unit cost compared with generic low‑cost alternatives
- Power demand of 600 kW can impact overall ship electrical allocation
Typical Vessels:
Container ships (up to ~150 m LOA)General cargo vesselsOffshore supply & support vesselsFerries and Ro‑Ro shipsCruise liners (mid‑size) LNG carriers (smaller classes)
Decision Guide: Choose if you need a reliable, high‑thrust bow thruster for vessels up to ~20 000 DWT with limited hull space and want proven integration with DP systems. Avoid if the vessel requires thrust above 80 kN, has severe budget constraints, or cannot accommodate the tunnel diameter without major structural modifications.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
Schottel STT Thruster 600kW stern
unverified
· 600.0 kW
· ducted tunnel thruster
Power (kW)
600
Thrust (kN)
72.0
Diameter (mm)
980
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (≈72 kN @ 600 kW)
- Compact installation footprint – fits into existing hull tunnels
- Robust, water‑lubricated bearings require low maintenance
- Low vibration and noise compared with open propellers
- Proven DNV type approval for marine applications
Weaknesses
- Fixed‑pitch blades limit thrust reversal capability versus azimuth units
- Maximum thrust may be insufficient for very large vessels or high‑speed DP operations
- Duct can accumulate debris; regular cleaning required to maintain efficiency
- Limited 360° thrust vectoring – only provides transverse force at the stern
Typical Vessels:
Cruise shipsFerriesOffshore supply vessels (OSV)Container feedersMedium‑size tankers and bulk carriers
Certifications:
DNV
Decision Guide: Choose if: you need a reliable, cost‑effective stern thruster for medium‑sized ships with limited hull space and moderate maneuvering requirements. Avoid if: the vessel requires high thrust levels, full 360° thrust vectoring, or variable‑pitch control typical of azimuth pods.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Schottel STT Thruster 800kW bow
unverified
· 800.0 kW
· integrated motor tunnel thruster
Power (kW)
800
Thrust (kN)
96.0
Diameter (mm)
1140
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (≈96 kN @ 800 kW) for precise low‑speed maneuvering
- Compact installation footprint, ideal for vessels with limited bow space
- Low cavitation and vibration thanks to the ducted design, reducing wear
- Robust construction with easy access for routine maintenance
- Class‑approved (DNV) and widely used in DP‑enabled ships
Weaknesses
- Fixed‑pitch propeller limits thrust modulation compared with controllable‑pitch options
- Initial capital cost higher than basic open‑propeller thrusters
- Requires duct cleaning to avoid performance loss from fouling
- Power rating may be insufficient for very large vessels (>40 000 DWT) needing higher maneuvering forces
Typical Vessels:
Product TankerHandymax Bulk CarrierOffshore Supply VesselCruise Ship (mid‑size)Container Feeder
Certifications:
DNV
Decision Guide: Choose if you need a high‑thrust, space‑efficient bow thruster for vessels up to ~40 000 DWT that require precise port handling or DP support. Avoid if hull geometry cannot accommodate the duct, if variable thrust control is essential, or when budget constraints favor lower‑cost open‑propeller units.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Schottel STT Thruster 800kW stern
unverified
· 800.0 kW
· tunnel thruster
Power (kW)
800
Thrust (kN)
96.0
Diameter (mm)
1140
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (≈96 kN @ 800 kW) for effective bow‑/stern‑sideway control
- Modular, ducted tunnel reduces cavitation and improves efficiency across a wide speed range
- Robust stainless‑steel construction with low maintenance intervals
- Integrated Schottel control system allows precise thrust vectoring and easy integration with DP packages
- Standard 1 140 mm tunnel diameter fits common hull openings without excessive structural reinforcement
Weaknesses
- Relatively large hull opening (≈1.14 m) may require additional strengthening in thin‑skinned vessels
- Higher upfront cost compared with generic low‑price Chinese thrusters
- Noise and vibration levels can be higher than those of propeller‑type azimuth thrusters at full power
- Installation space is limited on very narrow stern sections or vessels with restricted aft deck area
Typical Vessels:
Container shipBulk carrierTankerCruise linerOffshore supply vesselLNG carrier
Decision Guide: Choose if: you need reliable high thrust for a large vessel with sufficient stern opening, require integration with DP or advanced maneuvering systems, and value low maintenance. Avoid if: hull space is severely limited, budget constraints dominate, or the vessel operates primarily at high speed where a propeller‑type azimuth thruster would be more efficient.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Schottel STT Thruster 1000kW bow
unverified
· 1000.0 kW
· tunnel thruster
Power (kW)
1000
Thrust (kN)
120.0
Diameter (mm)
1300
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (≈120 kN at 1000 kW)
- Compact installation footprint suitable for retrofit in existing hulls
- Integrated Schottel control and monitoring system
- Proven reliability on large commercial vessels
- Low cavitation and noise levels compared with open‑propeller thrusters
Weaknesses
- Fixed‑direction thrust; requires helm angle change for reverse or side thrust
- Generally lower propulsive efficiency than azimuth pods at low speeds
- Installation demands hull penetration and structural reinforcement
- Duct lining can wear, leading to higher maintenance intervals
- High electrical/mechanical power demand for the delivered thrust
Typical Vessels:
Container ShipCruise ShipBulk CarrierTankerOffshore Supply Vessel
Decision Guide: Choose if you need a high‑thrust bow thruster for large vessels where space is limited and proven reliability is paramount. Avoid if you require full 360° thrust vectoring, maximum efficiency at low speeds, or want to minimise hull modifications.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
Schottel STT Thruster 1000kW stern
unverified
· 1000.0 kW
· Tunnel thruster
Power (kW)
1000
Thrust (kN)
120.0
Diameter (mm)
1300
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (≈120 kN at 1000 kW) for effective low‑speed control
- Compact ducted layout fits within limited hull space while protecting the propeller
- Robust steel housing and modular construction simplify installation and maintenance
- Integrated Schottel control system allows precise thrust vectoring and DP integration
- Proven reliability on a wide range of vessel types with long service history
Weaknesses
- Tunnel geometry can generate hull vibration and noise at higher ship speeds
- Duct fouling requires regular cleaning to maintain performance
- Less efficient than azimuth pods for high‑speed thrust, leading to higher fuel use in those regimes
- Installation demands internal hull space and structural reinforcement
- Limited effectiveness when operating against strong lateral currents compared with larger azimuth units
Typical Vessels:
Container shipBulk carrierTankerCruise linerOffshore supply vesselLNG carrier
Certifications:
DNV GL Type ApprovalABS Classification
Decision Guide: Choose if: you need a high‑thrust, compact maneuvering solution for vessels with limited bow or stern space and require reliable DP support. Avoid if: the vessel operates primarily at higher speeds where azimuth pods are more efficient, or hull space constraints prevent duct installation.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Schottel STT Thruster 1200kW bow
unverified
· 1200.0 kW
· tunnel thruster
Power (kW)
1200
Thrust (kN)
144.0
Diameter (mm)
1460
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust-to-power ratio (144 kN at 1200 kW)
- Compact ducted design fits within limited bow space
- Modular propeller allows quick inspection and replacement, reducing downtime
- Integrated control system compatible with most bridge consoles
- Low cavitation and noise compared with open‑propeller thrusters
Weaknesses
- Requires hull penetration and structural reinforcement, increasing installation cost
- Performance can drop in very shallow water due to duct suction effects
- Fixed thrust direction; cannot rotate like an azimuth pod for dynamic positioning
- Less maneuverability than azipod or steerable azimuth thrusters in tight maneuvers
- Potential hull vibration if mounting and isolation are not properly engineered
Typical Vessels:
Container ShipBulk CarrierGeneral Cargo VesselOffshore Supply VesselMid‑size Cruise ShipRo-Ro Ferry
Certifications:
DNVABS
Decision Guide: Choose the Schottel STT 1200 kW bow thruster when you need high lateral thrust in a compact package for vessels up to ~150 m LOA, especially where proven reliability and easy maintenance are priorities. Avoid if the vessel requires full 360° thrust vectoring, operates frequently in very shallow water, or budget constraints make extensive hull modifications prohibitive.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Schottel STT Thruster 1200kW stern
unverified
· 1200.0 kW
· twin‑propeller tunnel thruster
Power (kW)
1200
Thrust (kN)
144.0
Diameter (mm)
1460
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (144 kN at 1200 kW)
- Twin variable‑pitch propellers give excellent efficiency across a wide speed range
- Compact footprint fits into standard stern tunnels of large vessels
- Low cavitation and acoustic signature, suitable for noise‑sensitive applications
- Integrated control system compatible with DP packages
Weaknesses
- Higher capital cost than single‑propeller tunnel thrusters
- More complex maintenance (two propellers, gearboxes, variable‑pitch mechanisms)
- Requires substantial electrical supply and cooling capacity (1200 kW)
- Large diameter (≈1.46 m) may limit retrofit options in confined hull spaces
- Potential vibration issues if alignment is not optimal
Typical Vessels:
Container shipCruise linerOffshore supply vesselLNG carrierBulk carrierTanker
Certifications:
DNVABS
Decision Guide: Choose if you need high stern thrust for DP or tight‑berth manoeuvring and have sufficient power supply and hull space. Avoid if budget is limited, the vessel has restricted tunnel dimensions, or a simpler single‑propeller thruster meets the required thrust.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Schottel STT Thruster 1500kW bow
unverified
· 1500.0 kW
· Tunnel thruster
Power (kW)
1500
Thrust (kN)
180.0
Diameter (mm)
1700
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (≈180 kN at 1500 kW) suitable for large vessels
- Compact footprint fits within limited bow space
- Proven Schottel hydraulic drive with low cavitation risk
- Integrated control electronics compatible with most bridge systems
- Robust construction for harsh marine environments
Weaknesses
- Fixed‑direction thrust; cannot rotate like an azimuth unit
- Higher power consumption compared with smaller thrusters for the same vessel size
- Maintenance access can be restricted by tunnel geometry
- Noise and vibration levels higher than some ducted propeller designs
- Limited effectiveness at very low ship speeds or in strong currents without supplemental DP systems
Typical Vessels:
Container shipsBulk carriersTankersCruise linersLNG carriersOffshore supply vessels
Decision Guide: Choose if: you need a high‑thrust, space‑efficient bow thruster for a large vessel and prefer the reliability of a proven tunnel design. Avoid if: you require 360° thrust vectoring or primary dynamic positioning capability where an azimuth or pod thruster would be more effective.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Schottel STT Thruster 1500kW stern
unverified
· 1500.0 kW
· tunnel thruster
Power (kW)
1500
Thrust (kN)
180.0
Diameter (mm)
1700
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust-to-power ratio (~180 kN at 1500 kW)
- Compact installation footprint suitable for stern integration
- Robust, low‑maintenance construction with easy access panels
- Integrated control system compatible with most DP packages
- Proven performance on a wide range of large vessel types
Weaknesses
- Reduced efficiency at higher ship speeds compared to azimuth thrusters
- Potential for duct fouling and cavitation in heavy‑use environments
- Limited thrust vectoring (fixed direction) – requires hull turn for directional control
- Installation requires significant hull penetration and structural reinforcement
- May generate hull vibration/noise in certain operating regimes
Typical Vessels:
Cruise shipLNG carrierOffshore supply vesselLarge container shipBulk carrierTanker
Certifications:
DNVABS
Decision Guide: Choose if: you need high static thrust for docking, low‑speed maneuvering or DP on a large vessel and prefer a lower‑cost, compact solution to an azimuth unit. Avoid if: the vessel operates frequently at higher speeds, requires full 360° thrust vectoring, or has strict noise/vibration limits where a propeller‑type thruster is preferred.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Schottel STT Thruster 2000kW bow
unverified
· 2000.0 kW
· tunnel thruster
Power (kW)
2000
Thrust (kN)
240.0
Diameter (mm)
2100
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (≈240 kN at 2000 kW) for strong low‑speed manoeuvring
- Compact tunnel layout fits within limited bow space while preserving hull integrity
- Proven Schottel reliability with long service history and robust bearing design
- Integrated control electronics compatible with most DP systems
- Low vibration and noise compared with external azimuth thrusters
Weaknesses
- Large tunnel diameter (≈2.1 m) may require hull reinforcement and reduces available bow volume
- Higher initial installation cost than smaller conventional bow thrusters
- Maintenance of water‑lubricated bearings can be more demanding in harsh environments
- Potential for cavitation at very high RPM, limiting maximum thrust in some conditions
- Limited suitability for vessels with shallow draft or restricted under‑keel clearance
Typical Vessels:
Container shipsCruise linersOffshore supply vesselsLNG carriersRo‑Ro ferriesBulk carriers (large)
Certifications:
DNV GL Type Approval
Decision Guide: Choose if you need high thrust for precise low‑speed manoeuvring or DP on a vessel that can accommodate a ~2.1 m tunnel and where reliability and integration with existing control systems are priorities. Avoid if hull space is severely limited, draft restrictions prevent a large tunnel, or budget constraints preclude the higher upfront cost.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Schottel STT Thruster 2000kW stern
unverified
· 2000.0 kW
· tunnel thruster
Power (kW)
2000
Thrust (kN)
240.0
Diameter (mm)
2100
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (≈240 kN at 2 MW) for strong bow‑/stern‑side force.
- Compact tunnel design fits within limited hull space and reduces above‑deck clutter.
- Proven Schottel reliability with modular construction that simplifies maintenance.
- Integrated control system compatible with most ship bridge consoles and DP packages.
- Low vibration and noise compared with external propeller azimuth units.
Weaknesses
- Reduced efficiency at higher vessel speeds; best suited for low‑speed maneuvering only.
- Hull penetration required, increasing installation complexity and potential for water ingress if not sealed correctly.
- Susceptible to fouling in the tunnel duct, requiring regular cleaning on vessels operating in warm waters.
- Higher upfront cost than a basic single‑propeller bow thruster of similar power.
- Limited azimuth capability – thrust direction is fixed, unlike rotating pod or azipod units.
Typical Vessels:
Container shipsBulk carriersTankersCruise linersOffshore supply vessels
Decision Guide: Choose if the vessel needs strong low‑speed thrust in a confined hull space, values proven reliability and easy integration with existing bridge systems, or requires a backup thruster for dynamic positioning. Avoid if the ship operates primarily at higher speeds where azimuth thrusters are more efficient, or when budget constraints favour simpler bow‑thruster solutions.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
Schottel STT Thruster 2500kW bow
unverified
· 2500.0 kW
· Schottel Tunnel Thruster
Power (kW)
2500
Thrust (kN)
300.0
Diameter (mm)
2500
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (≈300 kN at 2500 kW) for rapid sideway movement
- Compact bow‑mounted tunnel reduces above‑deck clutter compared with azimuth units
- Sealed electric motor and propeller design gives low maintenance and high reliability
- Integrated control interface compatible with DP systems and ship bridge consoles
- Optional variable‑pitch propeller improves efficiency across a wide speed range
Weaknesses
- Significant hull penetration and structural reinforcement required during installation
- Fixed thrust direction; steering relies on separate rudders or nozzle deflection
- Higher upfront cost than basic rudder‑assist thrusters
- Weight and size may limit suitability for smaller vessels with restricted bow space
- Noise and vibration levels can be elevated at full power, requiring mitigation
Typical Vessels:
Container ShipBulk CarrierTankerCruise ShipOffshore Supply Vessel
Certifications:
ABS Type ApprovalDNV GL Classification
Decision Guide: Choose if the vessel needs high lateral thrust for DP or tight‑berth manoeuvring and has sufficient bow space for a 2.5 m tunnel. Avoid if hull reinforcement is impractical, budget constraints favour simpler thrusters, or an azimuthing unit is required for 360° thrust.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Schottel STT Thruster 2500kW stern
unverified
· 2500.0 kW
· integrated electric tunnel thruster
Power (kW)
2500
Thrust (kN)
300.0
Diameter (mm)
2500
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (~300 kN) at 2500 kW enables excellent maneuverability for large vessels.
- Compact 2.5 m tunnel fits within typical stern hull sections of bulk carriers and tankers.
- Integrated motor‑propeller design eliminates separate shaft alignment and reduces maintenance.
- Schottel’s proven hydraulic bearing system provides long service life and reliable operation.
- Variable frequency drive option allows fine thrust control and energy efficiency.
Weaknesses
- Large tunnel diameter requires significant hull penetration, limiting retrofit on smaller ships.
- Higher upfront installation cost compared with conventional azimuth thrusters of similar power.
- Weight and size add to vessel deadweight and may affect stability calculations.
- Full‑power operation can generate notable noise and vibration, requiring mitigation measures.
- Requires dedicated cooling water system integration and space for control electronics.
Typical Vessels:
Container shipBulk carrierOil tankerRo-Ro ferryOffshore supply vessel
Certifications:
DNVLloyd's Register
Decision Guide: Choose if: you need high thrust for a large vessel with sufficient stern space, require reliable low‑speed maneuverability, and value the proven Schottel service record. Avoid if: the ship’s hull cannot accommodate a 2.5 m tunnel, budget constraints prohibit higher installation costs, or noise/vibration limits are critical without additional mitigation.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Schottel STT Thruster 3000kW bow
unverified
· 3000.0 kW
· Tunnel thruster
Power (kW)
3000
Thrust (kN)
360.0
Diameter (mm)
2900
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust output (≈360 kN) for its power rating, enabling rapid lateral movements and DP support on large ships.
- Compact tunnel geometry (≈2.9 m diameter) fits within typical bow sections of vessels >100 000 dwt without excessive hull penetration.
- Robust Schottel‑engineered duct and propeller design reduces cavitation and extends service intervals.
- Integrated control electronics compatible with most bridge‑automation systems for precise thrust vectoring.
- Proven track record on a range of ocean‑going vessels, offering reliable performance in harsh sea conditions.
Weaknesses
- Large physical size limits installation on smaller hulls or vessels with restricted bow space.
- High initial capital cost and significant structural reinforcement may be required during retrofit.
- Maintenance access to the internal propeller can be cumbersome because of the enclosed tunnel layout.
- Noise and vibration levels are higher than some azimuth‑type thrusters at full power, requiring additional mitigation measures.
- Weight of the unit adds to overall vessel displacement, affecting payload calculations.
Typical Vessels:
Container shipCrude oil tankerProduct tankerBulk carrierLNG/LPG carrierCruise shipOffshore supply vessel
Decision Guide: Choose if: you need a bow thruster with >350 kN thrust for vessels larger than ~100 000 dwt, have sufficient bow volume for a ~2.9 m tunnel, and require proven reliability for DP or tight‑port maneuvers. Avoid if: the vessel is small to medium size, space constraints prevent installation of a large tunnel, or budget limits make lower‑power alternatives more attractive.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Schottel STT Thruster 3000kW stern
unverified
· 3000.0 kW
· high‑power tunnel thruster
Power (kW)
3000
Thrust (kN)
360.0
Diameter (mm)
2900
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (≈360 kN) for its power rating, giving excellent manoeuvreability on large ships
- Compact tunnel layout fits within standard hull sections without protruding blades
- Proven Schottel control system with integrated feedback and fault diagnostics
- Class‑approved design widely accepted by DNV, ABS and LR societies
- Low vibration and noise compared with external azimuth units
Weaknesses
- Requires a sizeable hull opening (≈2.9 m diameter) and reinforced tunnel structure
- High electrical power demand (3 MW) may strain ship’s power generation plant
- Water‑lubricated bearings need regular inspection to prevent corrosion
- Installation cost is significant; best suited for vessels where manoeuvring performance justifies expense
- Limited to stern or bow locations where sufficient flow straightness exists
Typical Vessels:
Cruise shipsLNG carriersOffshore supply & anchor handling tug supply (AHTS) vesselsLarge container ships (>10,000 TEU)Bulk carriers (>200 kDWT)
Certifications:
DNV class approvalABS class approvalLR class approval
Decision Guide: Choose if the vessel requires high thrust for precise low‑speed manoeuvring or DP, has sufficient hull space for a ~2.9 m tunnel, and can accommodate the 3 MW power draw. Avoid on small to medium vessels where the installation cost, hull penetration, and power demand outweigh the manoeuvre benefits, or when an azimuth thruster is preferred for 360° thrust vectoring.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
STT 60
✓ verified
Application
Tunnel Thruster (Bow/Stern) für Schiffe
Common Failures & Inspection Points
- Area: Inspection of seals and early detection of wear by means of LeaCon system (Seal Condition Monitoring)Check: Inspection of seals and early detection of wear by means of LeaCon system (Seal Condition Monitoring)
- Area: Regular inspection for water ingress and corrosion in the thruster chamberCheck: Regular inspection for water ingress and corrosion in the thruster chamber
- Area: Lubricating oil inspection, oil quality and regular oil change according to service planCheck: Lubricating oil inspection, oil quality and regular oil change according to service plan
- Area: Visual inspection of propeller for cracks, wear and cavitation damageCheck: Visual inspection of propeller for cracks, wear and cavitation damage
- Area: Inspection of bearings, wear parts (seals, gaskets, O-rings) for wearCheck: Inspection of bearings, wear parts (seals, gaskets, O-rings) for wear
- Area: Inspection of shaft seal for water leaks and oil leakageCheck: Inspection of shaft seal for water leaks and oil leakage
- Area: Inspection of tunnel for fouling by marine organisms and sludgingCheck: Inspection of tunnel for fouling by marine organisms and sludging
- Area: Five-year overhaul: disassembly, cleaning, inspection and replacement of wear partsCheck: Five-year overhaul: disassembly, cleaning, inspection and replacement of wear parts
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
STT 110
✓ verified
Application
Tunnel Thruster (Bow/Stern) für Schiffe
Common Failures & Inspection Points
- Area: Inspection of seals and early detection of wear by means of LeaCon system (Seal Condition Monitoring)Check: Inspection of seals and early detection of wear by means of LeaCon system (Seal Condition Monitoring)
- Area: Regular inspection for water ingress and corrosion in the thruster chamberCheck: Regular inspection for water ingress and corrosion in the thruster chamber
- Area: Lubricating oil inspection, oil quality and regular oil change according to service planCheck: Lubricating oil inspection, oil quality and regular oil change according to service plan
- Area: Visual inspection of propeller for cracks, wear and cavitation damageCheck: Visual inspection of propeller for cracks, wear and cavitation damage
- Area: Inspection of bearings, wear parts (seals, gaskets, O-rings) for wearCheck: Inspection of bearings, wear parts (seals, gaskets, O-rings) for wear
- Area: Inspection of shaft seal for water leaks and oil leakageCheck: Inspection of shaft seal for water leaks and oil leakage
- Area: Inspection of tunnel for fouling by marine organisms and sludgingCheck: Inspection of tunnel for fouling by marine organisms and sludging
- Area: Five-year overhaul: disassembly, cleaning, inspection and replacement of wear partsCheck: Five-year overhaul: disassembly, cleaning, inspection and replacement of wear parts
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
STT 170
✓ verified
Application
Tunnel thruster (bow/stern) for ships, river and coastal vessels
Common Failures & Inspection Points
- Area: Inspection of seals and early detection of wear by means of LeaCon system (Seal Condition Monitoring)Check: Inspection of seals and early detection of wear by means of LeaCon system (Seal Condition Monitoring)
- Area: Regular inspection for water ingress and corrosion in the thruster chamberCheck: Regular inspection for water ingress and corrosion in the thruster chamber
- Area: Lubricating oil inspection, oil quality and regular oil change according to service planCheck: Lubricating oil inspection, oil quality and regular oil change according to service plan
- Area: Visual inspection of propeller for cracks, wear and cavitation damageCheck: Visual inspection of propeller for cracks, wear and cavitation damage
- Area: Inspection of bearings, wear parts (seals, gaskets, O-rings) for wearCheck: Inspection of bearings, wear parts (seals, gaskets, O-rings) for wear
- Area: Inspection of shaft seal for water leaks and oil leakageCheck: Inspection of shaft seal for water leaks and oil leakage
- Area: Inspection of tunnel for fouling by marine organisms and sludgingCheck: Inspection of tunnel for fouling by marine organisms and sludging
- Area: Five-year overhaul: disassembly, cleaning, inspection and replacement of wear partsCheck: Five-year overhaul: disassembly, cleaning, inspection and replacement of wear parts
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
STT 170 LK
✓ verified
Application
Tunnel Thruster (Bow/Stern) mit Lärmoptimierung, Forschungsschiffe
Common Failures & Inspection Points
- Area: Inspection of seals and early detection of wear by means of LeaCon system (Seal Condition Monitoring)Check: Inspection of seals and early detection of wear by means of LeaCon system (Seal Condition Monitoring)
- Area: Regular inspection for water ingress and corrosion in the thruster chamberCheck: Regular inspection for water ingress and corrosion in the thruster chamber
- Area: Lubricating oil inspection, oil quality and regular oil change according to service planCheck: Lubricating oil inspection, oil quality and regular oil change according to service plan
- Area: Visual inspection of propeller for cracks, wear and cavitation damageCheck: Visual inspection of propeller for cracks, wear and cavitation damage
- Area: Inspection of bearings, wear parts (seals, gaskets, O-rings) for wearCheck: Inspection of bearings, wear parts (seals, gaskets, O-rings) for wear
- Area: Inspection of shaft seal for water leaks and oil leakageCheck: Inspection of shaft seal for water leaks and oil leakage
- Area: Inspection of tunnel for fouling by marine organisms and sludgingCheck: Inspection of tunnel for fouling by marine organisms and sludging
- Area: Five-year overhaul: disassembly, cleaning, inspection and replacement of wear partsCheck: Five-year overhaul: disassembly, cleaning, inspection and replacement of wear parts
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
STT 1
✓ verified
Application
Tunnel Thruster (Bow/Stern) für mittlere bis große Schiffe
Common Failures & Inspection Points
- Area: Inspection of seals and early detection of wear by means of LeaCon system (Seal Condition Monitoring)Check: Inspection of seals and early detection of wear by means of LeaCon system (Seal Condition Monitoring)
- Area: Regular inspection for water ingress and corrosion in the thruster chamberCheck: Regular inspection for water ingress and corrosion in the thruster chamber
- Area: Lubricating oil inspection, oil quality and regular oil change according to service planCheck: Lubricating oil inspection, oil quality and regular oil change according to service plan
- Area: Visual inspection of propeller for cracks, wear and cavitation damageCheck: Visual inspection of propeller for cracks, wear and cavitation damage
- Area: Inspection of bearings, wear parts (seals, gaskets, O-rings) for wearCheck: Inspection of bearings, wear parts (seals, gaskets, O-rings) for wear
- Area: Inspection of shaft seal for water leaks and oil leakageCheck: Inspection of shaft seal for water leaks and oil leakage
- Area: Inspection of tunnel for fouling by marine organisms and sludgingCheck: Inspection of tunnel for fouling by marine organisms and sludging
- Area: Five-year overhaul: disassembly, cleaning, inspection and replacement of wear partsCheck: Five-year overhaul: disassembly, cleaning, inspection and replacement of wear parts
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
STT 2 CP
✓ verified
Application
Tunnel Thruster (Bow/Stern) mit verstellbarem Propeller
Common Failures & Inspection Points
- Area: Inspection of seals and early detection of wear by means of LeaCon system (Seal Condition Monitoring)Check: Inspection of seals and early detection of wear by means of LeaCon system (Seal Condition Monitoring)
- Area: Regular inspection for water ingress and corrosion in the thruster chamberCheck: Regular inspection for water ingress and corrosion in the thruster chamber
- Area: Lubricating oil inspection, oil quality and regular oil change according to service planCheck: Lubricating oil inspection, oil quality and regular oil change according to service plan
- Area: Visual inspection of propeller for cracks, wear and cavitation damageCheck: Visual inspection of propeller for cracks, wear and cavitation damage
- Area: Inspection of bearings, wear parts (seals, gaskets, O-rings) for wearCheck: Inspection of bearings, wear parts (seals, gaskets, O-rings) for wear
- Area: Inspection of shaft seal for water leaks and oil leakageCheck: Inspection of shaft seal for water leaks and oil leakage
- Area: Inspection of tunnel for fouling by marine organisms and sludgingCheck: Inspection of tunnel for fouling by marine organisms and sludging
- Area: Five-year overhaul: disassembly, cleaning, inspection and replacement of wear partsCheck: Five-year overhaul: disassembly, cleaning, inspection and replacement of wear parts
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
STT 2
✓ verified
Application
Tunnel Thruster (Bow/Stern) für mittlere bis große Schiffe
Common Failures & Inspection Points
- Area: Inspection of seals and early detection of wear by means of LeaCon system (Seal Condition Monitoring)Check: Inspection of seals and early detection of wear by means of LeaCon system (Seal Condition Monitoring)
- Area: Regular inspection for water ingress and corrosion in the thruster chamberCheck: Regular inspection for water ingress and corrosion in the thruster chamber
- Area: Lubricating oil inspection, oil quality and regular oil change according to service planCheck: Lubricating oil inspection, oil quality and regular oil change according to service plan
- Area: Visual inspection of propeller for cracks, wear and cavitation damageCheck: Visual inspection of propeller for cracks, wear and cavitation damage
- Area: Inspection of bearings, wear parts (seals, gaskets, O-rings) for wearCheck: Inspection of bearings, wear parts (seals, gaskets, O-rings) for wear
- Area: Inspection of shaft seal for water leaks and oil leakageCheck: Inspection of shaft seal for water leaks and oil leakage
- Area: Inspection of tunnel for fouling by marine organisms and sludgingCheck: Inspection of tunnel for fouling by marine organisms and sludging
- Area: Five-year overhaul: disassembly, cleaning, inspection and replacement of wear partsCheck: Five-year overhaul: disassembly, cleaning, inspection and replacement of wear parts
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
STT 3
✓ verified
Application
Tunnel Thruster (Bow/Stern) für große Schiffe, Offshore-Anwendungen
Common Failures & Inspection Points
- Area: Inspection of seals and early detection of wear by means of LeaCon system (Seal Condition Monitoring)Check: Inspection of seals and early detection of wear by means of LeaCon system (Seal Condition Monitoring)
- Area: Regular inspection for water ingress and corrosion in the thruster chamberCheck: Regular inspection for water ingress and corrosion in the thruster chamber
- Area: Lubricating oil inspection, oil quality and regular oil change according to service planCheck: Lubricating oil inspection, oil quality and regular oil change according to service plan
- Area: Visual inspection of propeller for cracks, wear and cavitation damageCheck: Visual inspection of propeller for cracks, wear and cavitation damage
- Area: Inspection of bearings, wear parts (seals, gaskets, O-rings) for wearCheck: Inspection of bearings, wear parts (seals, gaskets, O-rings) for wear
- Area: Inspection of shaft seal for water leaks and oil leakageCheck: Inspection of shaft seal for water leaks and oil leakage
- Area: Inspection of tunnel for fouling by marine organisms and sludgingCheck: Inspection of tunnel for fouling by marine organisms and sludging
- Area: Five-year overhaul: disassembly, cleaning, inspection and replacement of wear partsCheck: Five-year overhaul: disassembly, cleaning, inspection and replacement of wear parts
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
STT 4
✓ verified
Application
Tunnel Thruster (Bow/Stern) für große Schiffe, Offshore-Operationen
Common Failures & Inspection Points
- Area: Inspection of seals and early detection of wear by means of LeaCon system (Seal Condition Monitoring)Check: Inspection of seals and early detection of wear by means of LeaCon system (Seal Condition Monitoring)
- Area: Regular inspection for water ingress and corrosion in the thruster chamberCheck: Regular inspection for water ingress and corrosion in the thruster chamber
- Area: Lubricating oil inspection, oil quality and regular oil change according to service planCheck: Lubricating oil inspection, oil quality and regular oil change according to service plan
- Area: Visual inspection of propeller for cracks, wear and cavitation damageCheck: Visual inspection of propeller for cracks, wear and cavitation damage
- Area: Inspection of bearings, wear parts (seals, gaskets, O-rings) for wearCheck: Inspection of bearings, wear parts (seals, gaskets, O-rings) for wear
- Area: Inspection of shaft seal for water leaks and oil leakageCheck: Inspection of shaft seal for water leaks and oil leakage
- Area: Inspection of tunnel for fouling by marine organisms and sludgingCheck: Inspection of tunnel for fouling by marine organisms and sludging
- Area: Five-year overhaul: disassembly, cleaning, inspection and replacement of wear partsCheck: Five-year overhaul: disassembly, cleaning, inspection and replacement of wear parts
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
STT 5
✓ verified
Application
Tunnel Thruster (Bow/Stern) für große Schiffe, Offshore-Dynamik-Positionierung
Common Failures & Inspection Points
- Area: Inspection of seals and early detection of wear by means of LeaCon system (Seal Condition Monitoring)Check: Inspection of seals and early detection of wear by means of LeaCon system (Seal Condition Monitoring)
- Area: Regular inspection for water ingress and corrosion in the thruster chamberCheck: Regular inspection for water ingress and corrosion in the thruster chamber
- Area: Lubricating oil inspection, oil quality and regular oil change according to service planCheck: Lubricating oil inspection, oil quality and regular oil change according to service plan
- Area: Visual inspection of propeller for cracks, wear and cavitation damageCheck: Visual inspection of propeller for cracks, wear and cavitation damage
- Area: Inspection of bearings, wear parts (seals, gaskets, O-rings) for wearCheck: Inspection of bearings, wear parts (seals, gaskets, O-rings) for wear
- Area: Inspection of shaft seal for water leaks and oil leakageCheck: Inspection of shaft seal for water leaks and oil leakage
- Area: Inspection of tunnel for fouling by marine organisms and sludgingCheck: Inspection of tunnel for fouling by marine organisms and sludging
- Area: Five-year overhaul: disassembly, cleaning, inspection and replacement of wear partsCheck: Five-year overhaul: disassembly, cleaning, inspection and replacement of wear parts
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
STT 6
✓ verified
Application
Tunnel Thruster (Bow/Stern) für sehr große Schiffe, schwere Offshore-Anwendungen
Common Failures & Inspection Points
- Area: Inspection of seals and early detection of wear by means of LeaCon system (Seal Condition Monitoring)Check: Inspection of seals and early detection of wear by means of LeaCon system (Seal Condition Monitoring)
- Area: Regular inspection for water ingress and corrosion in the thruster chamberCheck: Regular inspection for water ingress and corrosion in the thruster chamber
- Area: Lubricating oil inspection, oil quality and regular oil change according to service planCheck: Lubricating oil inspection, oil quality and regular oil change according to service plan
- Area: Visual inspection of propeller for cracks, wear and cavitation damageCheck: Visual inspection of propeller for cracks, wear and cavitation damage
- Area: Inspection of bearings, wear parts (seals, gaskets, O-rings) for wearCheck: Inspection of bearings, wear parts (seals, gaskets, O-rings) for wear
- Area: Inspection of shaft seal for water leaks and oil leakageCheck: Inspection of shaft seal for water leaks and oil leakage
- Area: Inspection of tunnel for fouling by marine organisms and sludgingCheck: Inspection of tunnel for fouling by marine organisms and sludging
- Area: Five-year overhaul: disassembly, cleaning, inspection and replacement of wear partsCheck: Five-year overhaul: disassembly, cleaning, inspection and replacement of wear parts
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
[08.08.2026] Datenblattlink entfernt (seite leer): https://www.maritimeinformed.com/schottel-stt-6-thruster-technical-details.html
STT 7
✓ verified
Application
Tunnel Thruster (Bow/Stern) für sehr große Schiffe, Dynamik-Positionierung
Common Failures & Inspection Points
- Area: Inspection of seals and early detection of wear by means of LeaCon system (Seal Condition Monitoring)Check: Inspection of seals and early detection of wear by means of LeaCon system (Seal Condition Monitoring)
- Area: Regular inspection for water ingress and corrosion in the thruster chamberCheck: Regular inspection for water ingress and corrosion in the thruster chamber
- Area: Lubricating oil inspection, oil quality and regular oil change according to service planCheck: Lubricating oil inspection, oil quality and regular oil change according to service plan
- Area: Visual inspection of propeller for cracks, wear and cavitation damageCheck: Visual inspection of propeller for cracks, wear and cavitation damage
- Area: Inspection of bearings, wear parts (seals, gaskets, O-rings) for wearCheck: Inspection of bearings, wear parts (seals, gaskets, O-rings) for wear
- Area: Inspection of shaft seal for water leaks and oil leakageCheck: Inspection of shaft seal for water leaks and oil leakage
- Area: Inspection of tunnel for fouling by marine organisms and sludgingCheck: Inspection of tunnel for fouling by marine organisms and sludging
- Area: Five-year overhaul: disassembly, cleaning, inspection and replacement of wear partsCheck: Five-year overhaul: disassembly, cleaning, inspection and replacement of wear parts
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
STT 610
✓ verified
Application
Tunnel Thruster (Bow/Stern) für Großschiffe, massive Offshore-Operationen
Common Failures & Inspection Points
- Area: Inspection of seals and early detection of wear by means of LeaCon system (Seal Condition Monitoring)Check: Inspection of seals and early detection of wear by means of LeaCon system (Seal Condition Monitoring)
- Area: Regular inspection for water ingress and corrosion in the thruster chamberCheck: Regular inspection for water ingress and corrosion in the thruster chamber
- Area: Lubricating oil inspection, oil quality and regular oil change according to service planCheck: Lubricating oil inspection, oil quality and regular oil change according to service plan
- Area: Visual inspection of propeller for cracks, wear and cavitation damageCheck: Visual inspection of propeller for cracks, wear and cavitation damage
- Area: Inspection of bearings, wear parts (seals, gaskets, O-rings) for wearCheck: Inspection of bearings, wear parts (seals, gaskets, O-rings) for wear
- Area: Inspection of shaft seal for water leaks and oil leakageCheck: Inspection of shaft seal for water leaks and oil leakage
- Area: Inspection of tunnel for fouling by marine organisms and sludgingCheck: Inspection of tunnel for fouling by marine organisms and sludging
- Area: Five-year overhaul: disassembly, cleaning, inspection and replacement of wear partsCheck: Five-year overhaul: disassembly, cleaning, inspection and replacement of wear parts
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
Veth Propulsion
34 ✓ 10 verified
Veth VL-T100 bow
unverified
· 100.0 kW
· tunnel thruster
Power (kW)
100
Thrust (kN)
11.0
Diameter (mm)
490
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (≈11 kN at 100 kW) for its size
- Compact 490 mm tunnel fits within standard hull sections without major redesign
- Bow placement provides effective low‑speed steering and docking assistance
- Veth’s reputation for robust, low‑maintenance marine propulsion units
- Simple fixed‑direction design reduces mechanical complexity
Weaknesses
- Fixed‑direction thrust limits maneuverability compared with azimuth thrusters
- Maximum thrust (11 kN) may be insufficient for larger vessels or heavy DP loads
- Tunnel geometry can be prone to cavitation noise at high RPMs
- Performance can degrade in very shallow water where tunnel inlet flow is restricted
- Power rating (100 kW) limits use on ships requiring higher bow‑thruster power
Typical Vessels:
Offshore supply vesselsCoastal ferriesSmall to medium bulk carriersContainer feeders up to ~5,000 gtGeneral cargo ships with moderate maneuvering needs
Decision Guide: Choose the VL‑T100 if you need a reliable, compact bow thruster delivering around 11 kN of thrust for vessels up to medium size and you prefer a simple fixed‑direction system with low maintenance. Avoid it on large tankers, cruise ships, or any vessel that requires higher thrust levels, 360° azimuth capability, or ultra‑quiet operation.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Veth VL-T100 stern
unverified
· 100.0 kW
· tunnel thruster
Power (kW)
100
Thrust (kN)
11.0
Diameter (mm)
490
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (≈11 kN at 100 kW) for its size
- Compact tunnel diameter (490 mm) fits vessels with limited hull space
- Robust, low‑maintenance construction typical of Veth’s tunnel designs
- Integrated control interface compatible with most ship bridge systems
- Suitable for retro‑fit on existing hulls due to standard stern mounting
Weaknesses
- Maximum thrust (11 kN) may be insufficient for large tankers or high‑power DP vessels
- Tunnel geometry can generate higher noise and vibration compared with ducted propellers
- Requires a hull penetration at the stern, adding complexity to installation
- Limited to low‑speed maneuvering; not intended for propulsion assistance
- Performance drops noticeably in very shallow water due to reduced inflow
Typical Vessels:
Offshore supply vesselFerry / Ro‑Ro shipMedium‑size container feederCruise ship tenderCoastal cargo vessel
Decision Guide: Choose if you need a reliable, space‑efficient stern thruster delivering ~11 kN of thrust for docking and low‑speed maneuvering on medium‑size vessels. Avoid if the vessel requires higher thrust levels (>15 kN), operates in very shallow water where tunnel inflow is restricted, or demands ultra‑quiet operation.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
Veth VL-T150 bow
unverified
· 150.0 kW
· electric tunnel thruster
Power (kW)
150
Thrust (kN)
16.5
Diameter (mm)
535
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Provides 16.5 kN thrust at 150 kW, giving a good thrust‑to‑power ratio for medium‑size ships
- Compact 535 mm tunnel diameter fits vessels with restricted hull space
- Integrated bow mounting improves low‑speed maneuverability and docking precision
- Tunnel design protects the propeller from debris and reduces external noise
- Veth Propulsion reputation for robust, low‑maintenance marine propulsion equipment
Weaknesses
- Requires hull penetration and structural reinforcement, adding installation complexity
- Thrust may be insufficient for very large vessels or extreme weather port operations
- Maintenance access can be limited compared with external azimuth units
- Fixed thrust direction limits flexibility; cannot provide lateral thrust without turning the vessel
Typical Vessels:
Offshore supply vesselFerrySmall to medium container ship (up to ~30,000 dwt)Cruise ship (mid‑size)Bulk carrier (up to ~20,000 dwt)
Decision Guide: Choose the VL‑T150 if you need a reliable moderate‑power bow thruster for vessels with limited hull space and typical port maneuvering requirements. Avoid it on very large ships or where higher thrust (>20 kN) or 360° azimuth capability is required.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
Veth VL-T150 stern
unverified
· 150.0 kW
· tunnel thruster
Power (kW)
150
Thrust (kN)
16.5
Diameter (mm)
535
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (16.5 kN from 150 kW).
- Compact 535 mm tunnel diameter fits tight hull spaces.
- Stainless‑steel housing provides excellent corrosion resistance and durability.
- Integrated variable frequency drive allows precise thrust control and low fuel consumption.
- Relatively low acoustic and vibration signature, beneficial for passenger comfort.
Weaknesses
- Maximum thrust (16.5 kN) may be insufficient for large tankers or high‑power tugs.
- Cavitation can become noticeable at high RPMs in shallow water conditions.
- Installation requires hull penetration and structural reinforcement, adding dock‑time.
- Not certified for ice‑class operations; unsuitable for Arctic service.
- Single unit provides no redundancy if a failure occurs during critical maneuvers.
Typical Vessels:
Offshore supply vesselFerrySmall to medium container shipCruise ship (mid‑size)Bulk carrier (up to ~30,000 dwt)
Certifications:
DNVABS
Decision Guide: Choose if you need a compact, high‑efficiency stern thruster for vessels up to roughly 30,000 dwt where space is limited and low noise is important. Avoid if the vessel requires >20 kN thrust, operates in ice conditions, or demands redundant maneuvering systems.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
Veth VL-T200 bow
unverified
· 200.0 kW
· tunnel bow thruster
Power (kW)
200
Thrust (kN)
22.0
Diameter (mm)
580
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (22 kN from 200 kW) for effective low‑speed manoeuvring
- Compact tunnel diameter (580 mm) fits vessels with limited hull space
- Robust stainless‑steel tunnel construction typical of Veth units, offering good durability
- Straightforward installation and maintenance access through the bow tunnel
Weaknesses
- Fixed‑direction thrust; no azimuth capability for vectoring
- Tunnel geometry can be prone to fouling and requires periodic duct cleaning
- Potential cavitation noise at full power, especially in shallow water
- Limited redundancy – a single unit means loss of bow thrust if it fails
Typical Vessels:
Offshore supply vesselFerrySmall to medium container shipCruise ship (mid‑size)Bulk carrier (up to ~30 000 dwt)
Decision Guide: Choose if you need a reliable, high‑thrust bow thruster for vessels with restricted hull space and operate mainly in ports or offshore DP support where fixed thrust is sufficient. Avoid if the vessel requires full azimuth manoeuvring, very low acoustic signature, or multiple redundant bow thrust units.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
Veth VL-T200 stern
unverified
· 200.0 kW
· tunnel thruster
Power (kW)
200
Thrust (kN)
22.0
Diameter (mm)
580
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (22 kN at 200 kW) for its size
- Compact 580 mm tunnel fits vessels with limited hull space
- Stern placement improves yaw control during docking and DP operations
- Robust tunnel design reduces fouling and protects the propeller
- Integrated motor‑driven unit simplifies installation
Weaknesses
- Maximum thrust of 22 kN may be insufficient for large tankers or high‑wind conditions
- Hull penetration required; potential for water ingress if seals degrade
- Tunnel geometry can generate hull vibration and noise at high RPMs
- Maintenance access to bearings and motor is limited compared with azimuth units
- Not optimized for ice‑class or heavy‑weather operations
Typical Vessels:
Container ship (up to ~30 000 DWT)Bulk carrier (up to ~25 000 DWT)General cargo vesselOffshore supply vesselFerry
Decision Guide: Choose if: you need a reliable, space‑efficient stern thruster for medium‑size vessels requiring moderate thrust and enhanced docking control; you operate in temperate waters without extreme ice or wind loads. Avoid if: the vessel demands higher thrust (>30 kN), operates in icy conditions, or requires an azimuthing unit for 360° thrust vectoring.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Veth VL-T300 bow
unverified
· 300.0 kW
· tunnel thruster
Power (kW)
300
Thrust (kN)
33.0
Diameter (mm)
670
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (33 kN at 300 kW) for its size
- Relatively compact tunnel diameter (670 mm) fits medium‑size hulls without excessive space penalty
- Proven Veth design with optimized water flow channels for efficiency
- Straightforward integration as a bow‑mounted unit, compatible with standard control systems
Weaknesses
- Requires hull penetration and internal ducting, increasing installation complexity
- Maintenance of bearings and seals can be more demanding than external azimuth units
- Noise and vibration levels are higher than some low‑speed propeller‑type thrusters
- Limited to fixed thrust direction; cannot provide 360° vectoring like azipods
Typical Vessels:
Offshore support vesselsContainer ships up to ~15,000 GTBulk carriers of similar sizeGeneral cargo vesselsFerries requiring enhanced low‑speed maneuverability
Decision Guide: Choose if: you need a high‑thrust bow thruster for vessels up to ~20,000 GT, operate in confined ports or require DP Level 1 assistance, and prefer a proven tunnel design with straightforward integration. Avoid if: you demand full 360° thrust vectoring, ultra‑low noise operation, or want to minimize hull penetrations.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Veth VL-T300 stern
unverified
· 300.0 kW
· tunnel thruster
Power (kW)
300
Thrust (kN)
33.0
Diameter (mm)
670
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (33 kN) relative to its 300 kW power rating
- Compact 670 mm tunnel fits in medium‑size hulls without excessive structural modification
- Robust steel housing typical of Veth designs, offering good durability and low maintenance
- Integrated control interface compatible with most ship bridge systems
Weaknesses
- Power consumption can be significant for vessels that operate the thruster frequently
- Potential cavitation at high RPMs in shallow water or when operating near full thrust
- Installation requires a relatively large tunnel opening, limiting use on very thin hull sections
- Thrust may be insufficient for very large vessels (>30 000 DWT) requiring higher maneuvering forces
Typical Vessels:
Product Tanker (up to ~30 k DWT)Container FeederBulk Carrier (up to ~35 k DWT)Offshore Supply VesselCruise Ship (mid‑size)
Decision Guide: Choose if: you need a reliable, high‑thrust stern thruster for vessels up to ~30–35 000 DWT and have sufficient hull thickness for a 670 mm tunnel. Avoid if: the vessel exceeds the thrust requirement, has very thin hull plating, or operating conditions demand ultra‑low noise or minimal power draw.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
Veth VL-T400 bow
unverified
· 400.0 kW
Power (kW)
400
Thrust (kN)
44.0
Diameter (mm)
760
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (44 kN at 400 kW) for efficient port handling
- Compact 760 mm tunnel diameter fits within limited hull space
- Robust, low‑vibration design typical of Veth tunnel thrusters
- Proven reliability with a long service history in commercial fleets
- Straightforward integration with existing ship control and DP systems
Weaknesses
- Requires a sizable hull penetration, affecting structural layout
- Less versatile than azimuth or pod thrusters for dynamic positioning
- Installation and alignment costs are higher than simple transverse propellers
- Noise and vibration can be transmitted to the hull if not properly isolated
- Maintenance of bearings and seals inside the tunnel can be labour‑intensive
Typical Vessels:
Ro‑Ro ferriesPassenger cruise ships (up to ~180 m)Offshore supply vesselsMedium‑size container or bulk carriersLNG/LPG carriers with moderate length
Certifications:
IMO Type Approval
Decision Guide: Choose if you need a proven, high‑thrust bow thruster for vessels up to ~200 m that operate in congested ports and require reliable low‑speed maneuverability. Avoid if the vessel relies on full dynamic positioning, needs 360° thrust coverage, or has severe weight/space constraints where an azimuth pod would be more suitable.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Veth VL-T400 stern
unverified
· 400.0 kW
· tunnel thruster
Power (kW)
400
Thrust (kN)
44.0
Diameter (mm)
760
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (44 kN at 400 kW) for effective low‑speed manoeuvring
- Robust, corrosion‑resistant housing suitable for harsh sea water environments
- Compact tunnel diameter (760 mm) allows installation in vessels with limited hull space
- Proven Veth engineering reputation for long service life and easy maintenance
- Low acoustic signature compared with azimuth units of similar power
Weaknesses
- Fixed‑direction thrust limits flexibility; not suitable where full 360° thrust is required
- Relatively high power draw may increase fuel consumption on vessels without dedicated thruster generators
- Installation requires a sizable hull penetration, potentially weakening local structural integrity
- Cavitation risk at high RPMs in shallow water or low‑speed operation
- Limited suitability for ultra‑large ships where higher thrust levels (>60 kN) are needed
Typical Vessels:
Container ship (up to ~8,000 TEU)Bulk carrier (handysize to panamax)Product tankerCruise ferryOffshore supply vessel
Decision Guide: Choose if: you need a reliable, high‑thrust stern thruster for vessels up to ~30 000 gt where space is limited and a fixed‑direction thrust device suffices (e.g., docking, low‑speed manoeuvring, DP‑assisted operations). Avoid if: the vessel requires 360° thrust vectoring, ultra‑low noise levels, or higher thrust than 44 kN; also avoid on ships where hull penetration must be minimized.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Veth VL-T500 bow
unverified
· 500.0 kW
· tunnel thruster
Power (kW)
500
Thrust (kN)
55.0
Diameter (mm)
850
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (55 kN @ 500 kW) for rapid lateral movement
- Compact tunnel diameter (850 mm) fits in limited hull space while providing strong bollard pull
- Integrated Veth control system with feedback for precise DP and close‑quarter handling
- Robust stainless‑steel ducting resistant to corrosion in harsh marine environments
- Proven reliability record from European offshore and container operators
Weaknesses
- Relatively high power demand may increase fuel consumption on low‑speed vessels
- Tunnel geometry can be prone to cavitation at very high RPM, requiring careful propeller selection
- Installation requires precise alignment of duct and shaft; retrofits can be costly
- Limited thrust compared with similarly powered azimuth pods for tug or DP‑intensive applications
- Maintenance access to the internal impeller is more involved than open‑propeller designs
Typical Vessels:
Container ship (≥8 000 gt)Crude oil / product tankerLNG carrierOffshore supply vesselCruise liner
Decision Guide: Choose if: you need a high‑thrust bow thruster for vessels >8,000 gt with limited hull space and want a proven tunnel design with integrated control. Avoid if: the project budget cannot accommodate 500 kW power consumption, or if an azimuth pod offers better maneuverability for tug‑type operations.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
Veth VL-T500 stern
unverified
· 500.0 kW
· tunnel thruster
Power (kW)
500
Thrust (kN)
55.0
Diameter (mm)
850
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (≈55 kN @ 500 kW) suitable for large ships
- Compact duct diameter of 850 mm eases hull integration
- Robust stainless‑steel housing and propeller design for long service life
- Low vibration and noise levels compared with open‑propeller thrusters
- Straightforward maintenance access through removable duct sections
Weaknesses
- Requires significant hull penetration and structural reinforcement
- Fixed‑direction thrust; not as versatile as azimuth or pod units for dynamic positioning
- Potential cavitation at high RPMs in shallow water conditions
- Installation space may be limited on vessels with narrow stern sections
Typical Vessels:
Container shipBulk carrierCrude oil tankerLiquefied gas carrierOffshore supply vesselCruise ship
Decision Guide: Choose if: you need a reliable, high‑thrust stern thruster for vessels >80 m LOA with sufficient power budget and space for an 850 mm duct. Avoid if: the vessel is small, has tight stern geometry, or requires 360° thrust vectoring for advanced DP operations.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
Veth VL-T600 bow
unverified
· 600.0 kW
· tunnel bow thruster
Power (kW)
600
Thrust (kN)
66.0
Diameter (mm)
940
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (66 kN @ 600 kW) for strong manoeuvring capability
- Compact tunnel layout fits within standard hull sections without protruding shafts
- Robust bearing and seal design reduces maintenance intervals
- Low acoustic signature, suitable for passenger or environmentally sensitive vessels
- Proven Veth propulsion brand with extensive service network
Weaknesses
- Large tunnel diameter (940 mm) may limit installation on vessels with narrow hull sections
- Higher electrical power demand compared with smaller thrusters of similar size
- Tunnel geometry can generate higher cavitation risk in very shallow water
- Limited reverse thrust capability relative to azimuth‑type units
Typical Vessels:
Container shipCruise linerOffshore supply vesselLNG carrierRo‑Ro ferry
Decision Guide: Choose if you need a powerful, reliable bow thruster for vessels >30 m beam where tunnel installation is feasible and DP or tight‑port manoeuvring is required. Avoid if hull geometry cannot accommodate a ~1 m tunnel, power supply is limited, or an azimuth thruster’s 360° thrust vectoring is essential.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Veth VL-T600 stern
unverified
· 600.0 kW
· high‑efficiency tunnel thruster
Power (kW)
600
Thrust (kN)
66.0
Diameter (mm)
940
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (66 kN at 600 kW) for excellent manoeuvring capability
- Large 940 mm duct diameter reduces cavitation and improves efficiency
- Robust, marine‑grade construction suited to continuous DP operation
- Integrated control electronics compatible with most ship bridge systems
- Optimised for stern installation where space is limited but high thrust is needed
Weaknesses
- Large physical size requires substantial hull penetration and structural reinforcement
- Higher initial cost compared with smaller or lower‑power thrusters
- Maintenance access can be difficult due to the size of the duct and propeller assembly
- Power demand (600 kW) may impact vessel electrical load planning
- Weight and centre‑of‑gravity effects must be carefully accounted for in ship stability calculations
Typical Vessels:
Cruise shipsLNG carriersOffshore supply vessels (DP3)Large container ships (>10 000 TEU)Very large crude carriers (VLCC) and tankers
Certifications:
DNV
Decision Guide: Choose if the vessel needs high stern thrust for DP or tight port manoeuvring, especially when bow thruster space is limited. Avoid on smaller ships or where budget and weight constraints outweigh the need for maximum thrust.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Veth VL-T800 bow
unverified
· 800.0 kW
· high‑thrust tunnel thruster
Power (kW)
800
Thrust (kN)
88.0
Diameter (mm)
1120
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (88 kN) relative to power input, giving strong manoeuvring capability
- Large 1120 mm duct diameter reduces cavitation risk and improves hydraulic efficiency
- Veth’s proprietary blade geometry provides low vibration and noise levels
- Robust construction suitable for continuous operation on demanding vessels
- Integrated control interface compatible with most modern bridge systems
Weaknesses
- 800 kW electrical demand requires substantial power generation capacity
- Physical size may limit installation on smaller hulls or retrofits
- Tunnel thrusters are prone to marine growth; regular cleaning is required
- Hull reinforcement needed around the tunnel opening adds construction complexity
- Higher initial investment compared with lower‑power alternatives
Typical Vessels:
Container ships (≥8,000 TEU)Cruise linersLNG carriersOffshore supply vesselsLarge Ro‑Ro ferries
Decision Guide: Choose if: you need strong bow thrust for a vessel ≥150 m LOA with ample electrical generation capacity and want proven low‑cavitation performance. Avoid if: the ship has limited power plant margin, tight hull space constraints, or operates primarily in shallow, debris‑laden waters where fouling would be excessive.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
Veth VL-T800 stern
unverified
· 800.0 kW
· Tunnel thruster
Power (kW)
800
Thrust (kN)
88.0
Diameter (mm)
1120
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (88 kN) relative to its power rating enables strong low‑speed manoeuvring.
- Large 1.12 m duct diameter reduces cavitation and improves hydraulic efficiency.
- Stern installation provides direct control of the vessel’s aft swing, useful for docking and DP support.
- Modular design allows integration with existing ship automation systems.
Weaknesses
- 800 kW power demand results in higher fuel consumption when operated continuously.
- Physical size (1120 mm diameter) may restrict installation on vessels with limited hull space or narrow stern sections.
- Requires substantial cooling‑water flow and robust sealing, increasing installation complexity.
- Higher initial cost compared with lower‑power thrusters of similar dimensions.
Typical Vessels:
Very Large Crude Carrier (VLCC)Container ship (>8 000 TEU)Cruise linerOffshore supply vesselDP‑class tanker
Decision Guide: Choose if: you need a high‑thrust stern thruster for large vessels that require precise low‑speed control, DP support, or rapid docking turnaround. Avoid if: the ship’s hull form cannot accommodate a 1.12 m duct, budget constraints limit power‑intensive equipment, or thrust requirements are modest.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
Veth VL-T1000 bow
unverified
· 1000.0 kW
· high‑power tunnel thruster
Power (kW)
1000
Thrust (kN)
110.0
Diameter (mm)
1300
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (110 kN) relative to power consumption (1 MW).
- Large 1300 mm duct provides strong low‑speed maneuvering capability.
- Integrated duct reduces propeller exposure, lowering noise and vibration levels.
- Modular design simplifies installation and aligns with Veth’s proven engineering standards.
- Shallow draft of the tunnel arrangement suits deep‑draft vessels where external thrusters are impractical.
Weaknesses
- Tunnel geometry can be prone to cavitation if operated at high RPMs or in low‑density water.
- Requires hull penetration and structural reinforcement, adding to construction complexity.
- Maintenance access is more limited compared with azimuth or podded thrusters.
- Duct fouling can degrade performance unless regular cleaning regimes are applied.
- Higher upfront cost than smaller conventional bow thrusters.
Typical Vessels:
Container ShipCruise ShipOffshore Support VesselLNG CarrierBulk Carrier
Certifications:
DNV
Decision Guide: Choose if: you need a high‑thrust bow thruster for vessels >30 000 GT, deep‑draft ships where external azimuth units are impractical, and you can accommodate hull modifications. Avoid if: the vessel operates primarily in shallow waters with high fouling risk, or if budget constraints favour lower‑power conventional thrusters.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
Veth VL-T1000 stern
unverified
· 1000.0 kW
· tunnel thruster
Power (kW)
1000
Thrust (kN)
110.0
Diameter (mm)
1300
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (110 kN) relative to power rating enables strong maneuverability for medium‑size vessels.
- Compact 1300 mm tunnel diameter fits within limited hull space while delivering effective flow through the tunnel.
- Robust stainless‑steel housing and corrosion‑resistant components reduce maintenance intervals.
- Integrated control electronics compatible with common ship bridge systems simplify installation.
- Proven Veth design reputation for reliability in harsh marine environments.
Weaknesses
- Large power demand (1 MW) increases vessel electrical load and may require upgraded generators.
- Installation requires significant hull reinforcement around the tunnel opening, adding dock‑time cost.
- Noise and vibration levels can be higher than smaller thrusters if not properly isolated.
- Limited thrust at very low ship speeds due to cavitation risk in high‑flow tunnels.
- Higher initial capital cost compared with lower‑power alternatives.
Typical Vessels:
Container ships (up to ~150 m LOA)General cargo vesselsMedium‑size tankersBulk carriers (handymax class)Offshore supply vessels
Decision Guide: Choose if the vessel requires strong stern thrust for port entry/exit, dynamic positioning support, or emergency maneuvering and can accommodate a 1 MW electric motor and hull reinforcement. Avoid if the ship has limited power generation capacity, operates in noise‑sensitive environments, or is small enough that a lower‑power thruster would suffice.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Veth VL-T1200 bow
unverified
· 1200.0 kW
· water‑lubricated tunnel thruster
Power (kW)
1200
Thrust (kN)
132.0
Diameter (mm)
1480
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust‑to‑power ratio (≈0.11 kN/kW) suitable for mega‑vessels
- Compact tunnel geometry fits within limited hull space while providing large duct diameter
- Low acoustic signature and vibration thanks to water‑lubricated bearings
- Integrated control electronics compatible with most DP‑2/DP‑3 systems
- Proven reliability on a range of DNV‑classed tankers and cruise ships
Weaknesses
- Installation requires significant hull penetration and structural reinforcement
- Tunnel design can be prone to cavitation in very shallow water or high‑speed forward operation
- Higher initial cost compared with smaller, off‑the‑shelf thrusters of similar power
- Maintenance access is limited once installed; dry‑dock periods are needed for major overhauls
Typical Vessels:
Crude oil tankerProduct tankerContainer ship (>8 000 TEU)Cruise linerLNG carrierOffshore supply vessel
Certifications:
DNV GL class approval
Decision Guide: Choose if: you need >120 kN of bow thrust on a large, deep‑draft vessel and have sufficient hull volume for a 1.48 m tunnel; low noise and integration with DP systems are priorities. Avoid if: the ship operates in very shallow ports where cavitation risk is high, or budget constraints favour smaller thrusters; azimuthing propulsion is required instead of fixed bow thrust.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Veth VL-T1200 stern
unverified
· 1200.0 kW
· tunnel thruster
Power (kW)
1200
Thrust (kN)
132.0
Diameter (mm)
1480
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (132 kN) suitable for large tankers and container ships
- 1200 kW motor provides strong low‑speed control for dynamic positioning
- Large 1480 mm tunnel diameter gives efficient water flow and reduced cavitation
- Robust construction typical of Veth Propulsion, aimed at long service intervals
Weaknesses
- Large physical size limits installation on vessels with restricted stern space
- High power rating leads to greater fuel consumption when used continuously
- Requires dedicated cooling and ventilation systems, adding to installation complexity
- Potentially higher upfront cost compared with lower‑power competitors
Typical Vessels:
Crude oil tankerProduct tankerContainer ship (≥8 000 TEU)Bulk carrier (≥150 kt)Cruise linerOffshore supply vessel
Decision Guide: Choose if: you need a high‑thrust stern thruster for large vessels requiring precise low‑speed handling or DP capability, and have sufficient stern space for a 1.48 m tunnel. Avoid if: vessel size is limited, power budget is tight, or a lower‑cost, lower‑thrust solution would meet the maneuvering requirements.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
Veth VL-T1500 bow
unverified
· 1500.0 kW
· electric tunnel thruster
Power (kW)
1500
Thrust (kN)
165.0
Diameter (mm)
1750
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust output (165 kN) for its size, enabling strong lateral force on large ships
- Large 1750 mm duct diameter reduces cavitation and improves hydraulic efficiency
- Compact bow‑mount design minimizes hull penetration compared with external azimuth units
- Integrated control electronics compatible with most ship bridge systems
Weaknesses
- High electrical power demand (1.5 MW) requires robust onboard power distribution
- Installation needs significant structural reinforcement of the bow area
- Cooling and ventilation requirements are greater than for smaller thrusters
- Spare‑part logistics may be limited in regions without a Veth service network
Typical Vessels:
Container ship (≥8 000 gt)Cruise linerLNG carrierOffshore supply vesselLarge Ro‑Ro ferry
Decision Guide: Choose if the vessel requires high bow thrust for port entry, dynamic positioning or emergency maneuvering and has sufficient electrical generation capacity. Avoid if the ship’s power plant is limited, budget constraints are tight, or a smaller, lower‑cost thruster would meet the manoeuvring requirements.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Veth VL-T1500 stern
unverified
· 1500.0 kW
· tunnel thruster
Power (kW)
1500
Thrust (kN)
165.0
Diameter (mm)
1750
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust output (165 kN) for its power rating, enabling effective DP and berth assistance on large ships.
- Robust stainless‑steel tunnel construction with proven resistance to cavitation and marine growth.
- Integrated control electronics compatible with most ship bridge automation systems.
- Relatively compact length compared to equivalent azimuth pods, saving deck space when installed sternward.
- Veth’s long service history provides confidence in reliability and spare‑part availability.
Weaknesses
- Large tunnel diameter (1.75 m) requires substantial hull penetration and reinforcement during installation.
- High electrical power demand (≈1.5 MW) may necessitate upgrades to ship power distribution systems.
- Fixed thrust direction limits maneuvering flexibility compared with rotating azimuth thrusters.
- Maintenance access can be challenging in confined stern spaces, increasing downtime if not planned.
- Initial procurement cost is higher than lower‑power tunnel units.
Typical Vessels:
LNG carrierOffshore supply vesselCruise shipContainer ship (large class)Bulk carrier (≥150 kt)Tanker with DP requirements
Decision Guide: Choose if: the vessel needs high stern thrust for dynamic positioning, emergency maneuvering or tight‑berth operations and can accommodate a 1.75 m tunnel opening and the associated power supply. Avoid if: hull space is limited, the ship’s power plant cannot support ~1.5 MW of thruster load, or a rotating azimuth unit would provide better overall manoeuvrability for the intended service.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Veth VL-T2000 bow
unverified
· 2000.0 kW
· high‑power tunnel thruster
Power (kW)
2000
Thrust (kN)
220.0
Diameter (mm)
2200
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust output (≈220 kN) suitable for mega‑vessels
- Large 2.2 m duct diameter reduces cavitation and improves efficiency
- Integrated control electronics compatible with most DP systems
- Robust steel construction for long service life in harsh marine environments
Weaknesses
- High electrical power demand (≈2 MW) requires substantial onboard generation capacity
- Large installation envelope may limit use on vessels with restricted hull space
- Tunnel geometry can be sensitive to hull deformation, requiring careful alignment during retro‑fit
- Maintenance access is more complex than for external azimuth thrusters
Typical Vessels:
Ultra‑large container shipsCrude oil tankers (VLCC/ULCC)LNG carriersCruise linersOffshore supply vessels with DP capability
Decision Guide: Choose if the vessel needs very high bow thrust for safe port entry, dynamic positioning or emergency maneuvering and has sufficient power generation capacity. Avoid if hull space is limited, the ship’s power plant cannot support a 2 MW load, or lower‑cost/compact thrusters meet the operational requirements.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
Veth VL-T2000 stern
unverified
· 2000.0 kW
· tunnel thruster
Power (kW)
2000
Thrust (kN)
220.0
Diameter (mm)
2200
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (220 kN) for its power rating, enabling strong lateral forces during docking and DP operations
- Compact tunnel geometry fits within standard stern hull sections while providing good protection against fouling
- Robust hydraulic‑driven drive with proven Veth reliability and low maintenance intervals
- Integrated control electronics compatible with most ship bridge/DP consoles
- Low acoustic signature compared with azimuth thrusters, beneficial for passenger comfort
Weaknesses
- Large tunnel diameter (2.2 m) limits installation to vessels with sufficient stern space
- High power demand (2 MW) increases overall vessel fuel consumption when used frequently
- Cavitation can occur at very high RPMs, requiring careful propeller‑blade design and monitoring
- Installation requires substantial structural reinforcement of the hull tunnel
- Higher upfront cost than smaller‑capacity thrusters
Typical Vessels:
Container ships (>8 000 TEU)Cruise linersOffshore supply vessels (OSV)LNG carriersRo‑Ro ferries
Certifications:
IMO Type ApprovalDNV GL Class
Decision Guide: Choose if you need a high‑thrust, reliable stern thruster for large vessels with adequate hull space and require strong manoeuvring or DP capability. Avoid if the vessel has limited stern volume, lower thrust requirements, or budget constraints that favour smaller thrusters.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
VT-50
✓ verified
Application
Bow/Stern Tunnel Thruster for small to medium commercial vessels and yachts
Common Failures & Inspection Points
- Area: Propeller blade condition: Inspect for cracks, erosion, cavitation pitting, and proper alignment; confirm no deformation or separationCheck: Propeller blade condition: Inspect for cracks, erosion, cavitation pitting, and proper alignment; confirm no deformation or separation
- Area: Gearbox/Gear Drive: Check for oil leaks, proper lubrication level, unusual noise during operation, and bearing wear indicatorsCheck: Gearbox/Gear Drive: Check for oil leaks, proper lubrication level, unusual noise during operation, and bearing wear indicators
- Area: Motor coupling and shaft alignment: Verify proper centering, inspect for cracks or misalignment causing vibrationCheck: Motor coupling and shaft alignment: Verify proper centering, inspect for cracks or misalignment causing vibration
- Area: Tunnel structure: Inspect for corrosion, cracks, material fatigue, and proper hull integration; ensure no water ingressCheck: Tunnel structure: Inspect for corrosion, cracks, material fatigue, and proper hull integration; ensure no water ingress
- Area: Seals and gaskets: Check all dynamic and static seals for leakage (oil, water), deterioration, and proper installationCheck: Seals and gaskets: Check all dynamic and static seals for leakage (oil, water), deterioration, and proper installation
- Area: Electric motor (if applicable): Test insulation resistance, verify cooling system function, check for bearing wear and overheatingCheck: Electric motor (if applicable): Test insulation resistance, verify cooling system function, check for bearing wear and overheating
- Area: Control system and hydraulic lines (if applicable): Inspect for leaks, proper pressure readings, response to directional commandsCheck: Control system and hydraulic lines (if applicable): Inspect for leaks, proper pressure readings, response to directional commands
- Area: Mounting brackets and fasteners: Verify structural integrity, check for corrosion and loose connections affecting stabilityCheck: Mounting brackets and fasteners: Verify structural integrity, check for corrosion and loose connections affecting stability
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
VT-90
✓ verified
Application
Bow/Stern Tunnel Thruster for medium commercial vessels
Common Failures & Inspection Points
- Area: Propeller blade condition: Inspect for cracks, erosion, cavitation pitting, and proper alignment; confirm no deformation or separationCheck: Propeller blade condition: Inspect for cracks, erosion, cavitation pitting, and proper alignment; confirm no deformation or separation
- Area: Gearbox/Gear Drive: Check for oil leaks, proper lubrication level, unusual noise during operation, and bearing wear indicatorsCheck: Gearbox/Gear Drive: Check for oil leaks, proper lubrication level, unusual noise during operation, and bearing wear indicators
- Area: Motor coupling and shaft alignment: Verify proper centering, inspect for cracks or misalignment causing vibrationCheck: Motor coupling and shaft alignment: Verify proper centering, inspect for cracks or misalignment causing vibration
- Area: Tunnel structure: Inspect for corrosion, cracks, material fatigue, and proper hull integration; ensure no water ingressCheck: Tunnel structure: Inspect for corrosion, cracks, material fatigue, and proper hull integration; ensure no water ingress
- Area: Seals and gaskets: Check all dynamic and static seals for leakage (oil, water), deterioration, and proper installationCheck: Seals and gaskets: Check all dynamic and static seals for leakage (oil, water), deterioration, and proper installation
- Area: Electric motor (if applicable): Test insulation resistance, verify cooling system function, check for bearing wear and overheatingCheck: Electric motor (if applicable): Test insulation resistance, verify cooling system function, check for bearing wear and overheating
- Area: Control system and hydraulic lines (if applicable): Inspect for leaks, proper pressure readings, response to directional commandsCheck: Control system and hydraulic lines (if applicable): Inspect for leaks, proper pressure readings, response to directional commands
- Area: Mounting brackets and fasteners: Verify structural integrity, check for corrosion and loose connections affecting stabilityCheck: Mounting brackets and fasteners: Verify structural integrity, check for corrosion and loose connections affecting stability
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
VT-180
✓ verified
Application
Bow/Stern Tunnel Thruster for medium to large commercial vessels
Common Failures & Inspection Points
- Area: Propeller blade condition: Inspect for cracks, erosion, cavitation pitting, and proper alignment; confirm no deformation or separationCheck: Propeller blade condition: Inspect for cracks, erosion, cavitation pitting, and proper alignment; confirm no deformation or separation
- Area: Gearbox/Gear Drive: Check for oil leaks, proper lubrication level, unusual noise during operation, and bearing wear indicatorsCheck: Gearbox/Gear Drive: Check for oil leaks, proper lubrication level, unusual noise during operation, and bearing wear indicators
- Area: Motor coupling and shaft alignment: Verify proper centering, inspect for cracks or misalignment causing vibrationCheck: Motor coupling and shaft alignment: Verify proper centering, inspect for cracks or misalignment causing vibration
- Area: Tunnel structure: Inspect for corrosion, cracks, material fatigue, and proper hull integration; ensure no water ingressCheck: Tunnel structure: Inspect for corrosion, cracks, material fatigue, and proper hull integration; ensure no water ingress
- Area: Seals and gaskets: Check all dynamic and static seals for leakage (oil, water), deterioration, and proper installationCheck: Seals and gaskets: Check all dynamic and static seals for leakage (oil, water), deterioration, and proper installation
- Area: Electric motor (if applicable): Test insulation resistance, verify cooling system function, check for bearing wear and overheatingCheck: Electric motor (if applicable): Test insulation resistance, verify cooling system function, check for bearing wear and overheating
- Area: Control system and hydraulic lines (if applicable): Inspect for leaks, proper pressure readings, response to directional commandsCheck: Control system and hydraulic lines (if applicable): Inspect for leaks, proper pressure readings, response to directional commands
- Area: Mounting brackets and fasteners: Verify structural integrity, check for corrosion and loose connections affecting stabilityCheck: Mounting brackets and fasteners: Verify structural integrity, check for corrosion and loose connections affecting stability
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
VT-240
✓ verified
Application
Bow/Stern Tunnel Thruster for large commercial vessels and offshore operations
Common Failures & Inspection Points
- Area: Propeller blade condition: Inspect for cracks, erosion, cavitation pitting, and proper alignment; confirm no deformation or separationCheck: Propeller blade condition: Inspect for cracks, erosion, cavitation pitting, and proper alignment; confirm no deformation or separation
- Area: Gearbox/Gear Drive: Check for oil leaks, proper lubrication level, unusual noise during operation, and bearing wear indicatorsCheck: Gearbox/Gear Drive: Check for oil leaks, proper lubrication level, unusual noise during operation, and bearing wear indicators
- Area: Motor coupling and shaft alignment: Verify proper centering, inspect for cracks or misalignment causing vibrationCheck: Motor coupling and shaft alignment: Verify proper centering, inspect for cracks or misalignment causing vibration
- Area: Tunnel structure: Inspect for corrosion, cracks, material fatigue, and proper hull integration; ensure no water ingressCheck: Tunnel structure: Inspect for corrosion, cracks, material fatigue, and proper hull integration; ensure no water ingress
- Area: Seals and gaskets: Check all dynamic and static seals for leakage (oil, water), deterioration, and proper installationCheck: Seals and gaskets: Check all dynamic and static seals for leakage (oil, water), deterioration, and proper installation
- Area: Electric motor (if applicable): Test insulation resistance, verify cooling system function, check for bearing wear and overheatingCheck: Electric motor (if applicable): Test insulation resistance, verify cooling system function, check for bearing wear and overheating
- Area: Control system and hydraulic lines (if applicable): Inspect for leaks, proper pressure readings, response to directional commandsCheck: Control system and hydraulic lines (if applicable): Inspect for leaks, proper pressure readings, response to directional commands
- Area: Mounting brackets and fasteners: Verify structural integrity, check for corrosion and loose connections affecting stabilityCheck: Mounting brackets and fasteners: Verify structural integrity, check for corrosion and loose connections affecting stability
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
VT-320
✓ verified
Application
Bow/Stern Tunnel Thruster for large commercial vessels and Dynamic Positioning (DP)
Common Failures & Inspection Points
- Area: Propeller blade condition: Inspect for cracks, erosion, cavitation pitting, and proper alignment; confirm no deformation or separationCheck: Propeller blade condition: Inspect for cracks, erosion, cavitation pitting, and proper alignment; confirm no deformation or separation
- Area: Gearbox/Gear Drive: Check for oil leaks, proper lubrication level, unusual noise during operation, and bearing wear indicatorsCheck: Gearbox/Gear Drive: Check for oil leaks, proper lubrication level, unusual noise during operation, and bearing wear indicators
- Area: Motor coupling and shaft alignment: Verify proper centering, inspect for cracks or misalignment causing vibrationCheck: Motor coupling and shaft alignment: Verify proper centering, inspect for cracks or misalignment causing vibration
- Area: Tunnel structure: Inspect for corrosion, cracks, material fatigue, and proper hull integration; ensure no water ingressCheck: Tunnel structure: Inspect for corrosion, cracks, material fatigue, and proper hull integration; ensure no water ingress
- Area: Seals and gaskets: Check all dynamic and static seals for leakage (oil, water), deterioration, and proper installationCheck: Seals and gaskets: Check all dynamic and static seals for leakage (oil, water), deterioration, and proper installation
- Area: Electric motor (if applicable): Test insulation resistance, verify cooling system function, check for bearing wear and overheatingCheck: Electric motor (if applicable): Test insulation resistance, verify cooling system function, check for bearing wear and overheating
- Area: Control system and hydraulic lines (if applicable): Inspect for leaks, proper pressure readings, response to directional commandsCheck: Control system and hydraulic lines (if applicable): Inspect for leaks, proper pressure readings, response to directional commands
- Area: Mounting brackets and fasteners: Verify structural integrity, check for corrosion and loose connections affecting stabilityCheck: Mounting brackets and fasteners: Verify structural integrity, check for corrosion and loose connections affecting stability
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
VT-400
✓ verified
Application
Bow/Stern Tunnel Thruster for large commercial vessels and offshore/DP applications
Common Failures & Inspection Points
- Area: Propeller blade condition: Inspect for cracks, erosion, cavitation pitting, and proper alignment; confirm no deformation or separationCheck: Propeller blade condition: Inspect for cracks, erosion, cavitation pitting, and proper alignment; confirm no deformation or separation
- Area: Gearbox/Gear Drive: Check for oil leaks, proper lubrication level, unusual noise during operation, and bearing wear indicatorsCheck: Gearbox/Gear Drive: Check for oil leaks, proper lubrication level, unusual noise during operation, and bearing wear indicators
- Area: Motor coupling and shaft alignment: Verify proper centering, inspect for cracks or misalignment causing vibrationCheck: Motor coupling and shaft alignment: Verify proper centering, inspect for cracks or misalignment causing vibration
- Area: Tunnel structure: Inspect for corrosion, cracks, material fatigue, and proper hull integration; ensure no water ingressCheck: Tunnel structure: Inspect for corrosion, cracks, material fatigue, and proper hull integration; ensure no water ingress
- Area: Seals and gaskets: Check all dynamic and static seals for leakage (oil, water), deterioration, and proper installationCheck: Seals and gaskets: Check all dynamic and static seals for leakage (oil, water), deterioration, and proper installation
- Area: Electric motor (if applicable): Test insulation resistance, verify cooling system function, check for bearing wear and overheatingCheck: Electric motor (if applicable): Test insulation resistance, verify cooling system function, check for bearing wear and overheating
- Area: Control system and hydraulic lines (if applicable): Inspect for leaks, proper pressure readings, response to directional commandsCheck: Control system and hydraulic lines (if applicable): Inspect for leaks, proper pressure readings, response to directional commands
- Area: Mounting brackets and fasteners: Verify structural integrity, check for corrosion and loose connections affecting stabilityCheck: Mounting brackets and fasteners: Verify structural integrity, check for corrosion and loose connections affecting stability
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
VT-550A
✓ verified
Application
Bow/Stern Tunnel Thruster for large commercial and offshore vessels
Common Failures & Inspection Points
- Area: Propeller blade condition: Inspect for cracks, erosion, cavitation pitting, and proper alignment; confirm no deformation or separationCheck: Propeller blade condition: Inspect for cracks, erosion, cavitation pitting, and proper alignment; confirm no deformation or separation
- Area: Gearbox/Gear Drive: Check for oil leaks, proper lubrication level, unusual noise during operation, and bearing wear indicatorsCheck: Gearbox/Gear Drive: Check for oil leaks, proper lubrication level, unusual noise during operation, and bearing wear indicators
- Area: Motor coupling and shaft alignment: Verify proper centering, inspect for cracks or misalignment causing vibrationCheck: Motor coupling and shaft alignment: Verify proper centering, inspect for cracks or misalignment causing vibration
- Area: Tunnel structure: Inspect for corrosion, cracks, material fatigue, and proper hull integration; ensure no water ingressCheck: Tunnel structure: Inspect for corrosion, cracks, material fatigue, and proper hull integration; ensure no water ingress
- Area: Seals and gaskets: Check all dynamic and static seals for leakage (oil, water), deterioration, and proper installationCheck: Seals and gaskets: Check all dynamic and static seals for leakage (oil, water), deterioration, and proper installation
- Area: Electric motor (if applicable): Test insulation resistance, verify cooling system function, check for bearing wear and overheatingCheck: Electric motor (if applicable): Test insulation resistance, verify cooling system function, check for bearing wear and overheating
- Area: Control system and hydraulic lines (if applicable): Inspect for leaks, proper pressure readings, response to directional commandsCheck: Control system and hydraulic lines (if applicable): Inspect for leaks, proper pressure readings, response to directional commands
- Area: Mounting brackets and fasteners: Verify structural integrity, check for corrosion and loose connections affecting stabilityCheck: Mounting brackets and fasteners: Verify structural integrity, check for corrosion and loose connections affecting stability
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
VT-700(A)
✓ verified
Application
Bow/Stern Tunnel Thruster for large commercial and offshore vessels
Common Failures & Inspection Points
- Area: Propeller blade condition: Inspect for cracks, erosion, cavitation pitting, and proper alignment; confirm no deformation or separationCheck: Propeller blade condition: Inspect for cracks, erosion, cavitation pitting, and proper alignment; confirm no deformation or separation
- Area: Gearbox/Gear Drive: Check for oil leaks, proper lubrication level, unusual noise during operation, and bearing wear indicatorsCheck: Gearbox/Gear Drive: Check for oil leaks, proper lubrication level, unusual noise during operation, and bearing wear indicators
- Area: Motor coupling and shaft alignment: Verify proper centering, inspect for cracks or misalignment causing vibrationCheck: Motor coupling and shaft alignment: Verify proper centering, inspect for cracks or misalignment causing vibration
- Area: Tunnel structure: Inspect for corrosion, cracks, material fatigue, and proper hull integration; ensure no water ingressCheck: Tunnel structure: Inspect for corrosion, cracks, material fatigue, and proper hull integration; ensure no water ingress
- Area: Seals and gaskets: Check all dynamic and static seals for leakage (oil, water), deterioration, and proper installationCheck: Seals and gaskets: Check all dynamic and static seals for leakage (oil, water), deterioration, and proper installation
- Area: Electric motor (if applicable): Test insulation resistance, verify cooling system function, check for bearing wear and overheatingCheck: Electric motor (if applicable): Test insulation resistance, verify cooling system function, check for bearing wear and overheating
- Area: Control system and hydraulic lines (if applicable): Inspect for leaks, proper pressure readings, response to directional commandsCheck: Control system and hydraulic lines (if applicable): Inspect for leaks, proper pressure readings, response to directional commands
- Area: Mounting brackets and fasteners: Verify structural integrity, check for corrosion and loose connections affecting stabilityCheck: Mounting brackets and fasteners: Verify structural integrity, check for corrosion and loose connections affecting stability
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
VT-900(A)
✓ verified
Application
Bow/Stern Tunnel Thruster for large commercial and Dynamic Positioning systems
Common Failures & Inspection Points
- Area: Propeller blade condition: Inspect for cracks, erosion, cavitation pitting, and proper alignment; confirm no deformation or separationCheck: Propeller blade condition: Inspect for cracks, erosion, cavitation pitting, and proper alignment; confirm no deformation or separation
- Area: Gearbox/Gear Drive: Check for oil leaks, proper lubrication level, unusual noise during operation, and bearing wear indicatorsCheck: Gearbox/Gear Drive: Check for oil leaks, proper lubrication level, unusual noise during operation, and bearing wear indicators
- Area: Motor coupling and shaft alignment: Verify proper centering, inspect for cracks or misalignment causing vibrationCheck: Motor coupling and shaft alignment: Verify proper centering, inspect for cracks or misalignment causing vibration
- Area: Tunnel structure: Inspect for corrosion, cracks, material fatigue, and proper hull integration; ensure no water ingressCheck: Tunnel structure: Inspect for corrosion, cracks, material fatigue, and proper hull integration; ensure no water ingress
- Area: Seals and gaskets: Check all dynamic and static seals for leakage (oil, water), deterioration, and proper installationCheck: Seals and gaskets: Check all dynamic and static seals for leakage (oil, water), deterioration, and proper installation
- Area: Electric motor (if applicable): Test insulation resistance, verify cooling system function, check for bearing wear and overheatingCheck: Electric motor (if applicable): Test insulation resistance, verify cooling system function, check for bearing wear and overheating
- Area: Control system and hydraulic lines (if applicable): Inspect for leaks, proper pressure readings, response to directional commandsCheck: Control system and hydraulic lines (if applicable): Inspect for leaks, proper pressure readings, response to directional commands
- Area: Mounting brackets and fasteners: Verify structural integrity, check for corrosion and loose connections affecting stabilityCheck: Mounting brackets and fasteners: Verify structural integrity, check for corrosion and loose connections affecting stability
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
VT-1250
✓ verified
Application
Bow/Stern Tunnel Thruster for large commercial and Deep Sea/DP operations
Common Failures & Inspection Points
- Area: Propeller blade condition: Inspect for cracks, erosion, cavitation pitting, and proper alignment; confirm no deformation or separationCheck: Propeller blade condition: Inspect for cracks, erosion, cavitation pitting, and proper alignment; confirm no deformation or separation
- Area: Gearbox/Gear Drive: Check for oil leaks, proper lubrication level, unusual noise during operation, and bearing wear indicatorsCheck: Gearbox/Gear Drive: Check for oil leaks, proper lubrication level, unusual noise during operation, and bearing wear indicators
- Area: Motor coupling and shaft alignment: Verify proper centering, inspect for cracks or misalignment causing vibrationCheck: Motor coupling and shaft alignment: Verify proper centering, inspect for cracks or misalignment causing vibration
- Area: Tunnel structure: Inspect for corrosion, cracks, material fatigue, and proper hull integration; ensure no water ingressCheck: Tunnel structure: Inspect for corrosion, cracks, material fatigue, and proper hull integration; ensure no water ingress
- Area: Seals and gaskets: Check all dynamic and static seals for leakage (oil, water), deterioration, and proper installationCheck: Seals and gaskets: Check all dynamic and static seals for leakage (oil, water), deterioration, and proper installation
- Area: Electric motor (if applicable): Test insulation resistance, verify cooling system function, check for bearing wear and overheatingCheck: Electric motor (if applicable): Test insulation resistance, verify cooling system function, check for bearing wear and overheating
- Area: Control system and hydraulic lines (if applicable): Inspect for leaks, proper pressure readings, response to directional commandsCheck: Control system and hydraulic lines (if applicable): Inspect for leaks, proper pressure readings, response to directional commands
- Area: Mounting brackets and fasteners: Verify structural integrity, check for corrosion and loose connections affecting stabilityCheck: Mounting brackets and fasteners: Verify structural integrity, check for corrosion and loose connections affecting stability
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
Sleipner Group
11 ✓ 11 verified
SE40/125S2
✓ verified
Application
Tunnel bow/stern thruster for motor and sailboats 26-34 feet
Common Failures & Inspection Points
- Area: Inspect seals and surfaces of propeller and gearleg for marine growth buildup; clean and apply anti-fouling paint before each seasonCheck: Inspect seals and surfaces of propeller and gearleg for marine growth buildup; clean and apply anti-fouling paint before each season
- Area: Check zinc anode for corrosion; replace when half of anode has eroded or before each seasonCheck: Check zinc anode for corrosion; replace when half of anode has eroded or before each season
- Area: Verify all electrical connections are clean, firmly fastened, and free from corrosion or moistureCheck: Verify all electrical connections are clean, firmly fastened, and free from corrosion or moisture
- Area: Inspect tunnel interior and surrounding boat hull area for water intrusion, oil leaks, or signs of damageCheck: Inspect tunnel interior and surrounding boat hull area for water intrusion, oil leaks, or signs of damage
- Area: Test motor operation with full thrust cycles; ensure smooth operation without grinding or unusual noiseCheck: Test motor operation with full thrust cycles; ensure smooth operation without grinding or unusual noise
- Area: Verify galvanic isolation integrity and test electrical continuity of protective systemsCheck: Verify galvanic isolation integrity and test electrical continuity of protective systems
- Area: Inspect ceramic seals and sealed drive lubrication system for leaks; ensure gearleg remains properly sealedCheck: Inspect ceramic seals and sealed drive lubrication system for leaks; ensure gearleg remains properly sealed
- Area: Check propeller blades for damage, deformation, or imbalance that could affect thrust performanceCheck: Check propeller blades for damage, deformation, or imbalance that could affect thrust performance
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
SEP40/125S2
✓ verified
Application
Tunnel bow/stern thruster with variable speed control for motor and sailboats 22-34 feet
Common Failures & Inspection Points
- Area: Inspect seals and surfaces of propeller and gearleg for marine growth buildup; clean and apply anti-fouling paint before each seasonCheck: Inspect seals and surfaces of propeller and gearleg for marine growth buildup; clean and apply anti-fouling paint before each season
- Area: Check zinc anode for corrosion; replace when half of anode has eroded or before each seasonCheck: Check zinc anode for corrosion; replace when half of anode has eroded or before each season
- Area: Verify all electrical connections are clean, firmly fastened, and free from corrosion or moistureCheck: Verify all electrical connections are clean, firmly fastened, and free from corrosion or moisture
- Area: Inspect tunnel interior and surrounding boat hull area for water intrusion, oil leaks, or signs of damageCheck: Inspect tunnel interior and surrounding boat hull area for water intrusion, oil leaks, or signs of damage
- Area: Test motor operation with full thrust cycles; ensure smooth operation without grinding or unusual noiseCheck: Test motor operation with full thrust cycles; ensure smooth operation without grinding or unusual noise
- Area: Verify galvanic isolation integrity and test electrical continuity of protective systemsCheck: Verify galvanic isolation integrity and test electrical continuity of protective systems
- Area: Inspect ceramic seals and sealed drive lubrication system for leaks; ensure gearleg remains properly sealedCheck: Inspect ceramic seals and sealed drive lubrication system for leaks; ensure gearleg remains properly sealed
- Area: Check propeller blades for damage, deformation, or imbalance that could affect thrust performanceCheck: Check propeller blades for damage, deformation, or imbalance that could affect thrust performance
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
SEP60/185S2-24V
✓ verified
Application
Tunnel bow/stern thruster with variable speed control for motor and sailboats 26-36 feet
Common Failures & Inspection Points
- Area: Inspect seals and surfaces of propeller and gearleg for marine growth buildup; clean and apply anti-fouling paint before each seasonCheck: Inspect seals and surfaces of propeller and gearleg for marine growth buildup; clean and apply anti-fouling paint before each season
- Area: Check zinc anode for corrosion; replace when half of anode has eroded or before each seasonCheck: Check zinc anode for corrosion; replace when half of anode has eroded or before each season
- Area: Verify all electrical connections are clean, firmly fastened, and free from corrosion or moistureCheck: Verify all electrical connections are clean, firmly fastened, and free from corrosion or moisture
- Area: Inspect tunnel interior and surrounding boat hull area for water intrusion, oil leaks, or signs of damageCheck: Inspect tunnel interior and surrounding boat hull area for water intrusion, oil leaks, or signs of damage
- Area: Test motor operation with full thrust cycles; ensure smooth operation without grinding or unusual noiseCheck: Test motor operation with full thrust cycles; ensure smooth operation without grinding or unusual noise
- Area: Verify galvanic isolation integrity and test electrical continuity of protective systemsCheck: Verify galvanic isolation integrity and test electrical continuity of protective systems
- Area: Inspect ceramic seals and sealed drive lubrication system for leaks; ensure gearleg remains properly sealedCheck: Inspect ceramic seals and sealed drive lubrication system for leaks; ensure gearleg remains properly sealed
- Area: Check propeller blades for damage, deformation, or imbalance that could affect thrust performanceCheck: Check propeller blades for damage, deformation, or imbalance that could affect thrust performance
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
SEP80/185T-12V
✓ verified
Application
Tunnel bow/stern thruster with variable speed control for motor and sailboats 32-49 feet
Common Failures & Inspection Points
- Area: Inspect seals and surfaces of propeller and gearleg for marine growth buildup; clean and apply anti-fouling paint before each seasonCheck: Inspect seals and surfaces of propeller and gearleg for marine growth buildup; clean and apply anti-fouling paint before each season
- Area: Check zinc anode for corrosion; replace when half of anode has eroded or before each seasonCheck: Check zinc anode for corrosion; replace when half of anode has eroded or before each season
- Area: Verify all electrical connections are clean, firmly fastened, and free from corrosion or moistureCheck: Verify all electrical connections are clean, firmly fastened, and free from corrosion or moisture
- Area: Inspect tunnel interior and surrounding boat hull area for water intrusion, oil leaks, or signs of damageCheck: Inspect tunnel interior and surrounding boat hull area for water intrusion, oil leaks, or signs of damage
- Area: Test motor operation with full thrust cycles; ensure smooth operation without grinding or unusual noiseCheck: Test motor operation with full thrust cycles; ensure smooth operation without grinding or unusual noise
- Area: Verify galvanic isolation integrity and test electrical continuity of protective systemsCheck: Verify galvanic isolation integrity and test electrical continuity of protective systems
- Area: Inspect ceramic seals and sealed drive lubrication system for leaks; ensure gearleg remains properly sealedCheck: Inspect ceramic seals and sealed drive lubrication system for leaks; ensure gearleg remains properly sealed
- Area: Check propeller blades for damage, deformation, or imbalance that could affect thrust performanceCheck: Check propeller blades for damage, deformation, or imbalance that could affect thrust performance
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
SEP80/185T-24V
✓ verified
Application
Tunnel bow/stern thruster with variable speed control for motor and sailboats 32-49 feet
Common Failures & Inspection Points
- Area: Inspect seals and surfaces of propeller and gearleg for marine growth buildup; clean and apply anti-fouling paint before each seasonCheck: Inspect seals and surfaces of propeller and gearleg for marine growth buildup; clean and apply anti-fouling paint before each season
- Area: Check zinc anode for corrosion; replace when half of anode has eroded or before each seasonCheck: Check zinc anode for corrosion; replace when half of anode has eroded or before each season
- Area: Verify all electrical connections are clean, firmly fastened, and free from corrosion or moistureCheck: Verify all electrical connections are clean, firmly fastened, and free from corrosion or moisture
- Area: Inspect tunnel interior and surrounding boat hull area for water intrusion, oil leaks, or signs of damageCheck: Inspect tunnel interior and surrounding boat hull area for water intrusion, oil leaks, or signs of damage
- Area: Test motor operation with full thrust cycles; ensure smooth operation without grinding or unusual noiseCheck: Test motor operation with full thrust cycles; ensure smooth operation without grinding or unusual noise
- Area: Verify galvanic isolation integrity and test electrical continuity of protective systemsCheck: Verify galvanic isolation integrity and test electrical continuity of protective systems
- Area: Inspect ceramic seals and sealed drive lubrication system for leaks; ensure gearleg remains properly sealedCheck: Inspect ceramic seals and sealed drive lubrication system for leaks; ensure gearleg remains properly sealed
- Area: Check propeller blades for damage, deformation, or imbalance that could affect thrust performanceCheck: Check propeller blades for damage, deformation, or imbalance that could affect thrust performance
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
SEP170/250TC-24V
✓ verified
Application
Tunnel bow/stern thruster with variable speed control for motor and sailboats 49-72 feet
Common Failures & Inspection Points
- Area: Inspect seals and surfaces of propeller and gearleg for marine growth buildup; clean and apply anti-fouling paint before each seasonCheck: Inspect seals and surfaces of propeller and gearleg for marine growth buildup; clean and apply anti-fouling paint before each season
- Area: Check zinc anode for corrosion; replace when half of anode has eroded or before each seasonCheck: Check zinc anode for corrosion; replace when half of anode has eroded or before each season
- Area: Verify all electrical connections are clean, firmly fastened, and free from corrosion or moistureCheck: Verify all electrical connections are clean, firmly fastened, and free from corrosion or moisture
- Area: Inspect tunnel interior and surrounding boat hull area for water intrusion, oil leaks, or signs of damageCheck: Inspect tunnel interior and surrounding boat hull area for water intrusion, oil leaks, or signs of damage
- Area: Test motor operation with full thrust cycles; ensure smooth operation without grinding or unusual noiseCheck: Test motor operation with full thrust cycles; ensure smooth operation without grinding or unusual noise
- Area: Verify galvanic isolation integrity and test electrical continuity of protective systemsCheck: Verify galvanic isolation integrity and test electrical continuity of protective systems
- Area: Inspect ceramic seals and sealed drive lubrication system for leaks; ensure gearleg remains properly sealedCheck: Inspect ceramic seals and sealed drive lubrication system for leaks; ensure gearleg remains properly sealed
- Area: Check propeller blades for damage, deformation, or imbalance that could affect thrust performanceCheck: Check propeller blades for damage, deformation, or imbalance that could affect thrust performance
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
E170/250TC-24V
✓ verified
Application
eVision tunnel bow/stern thruster with variable speed control and ignition protection for motor and sailboats 49-72 feet
Common Failures & Inspection Points
- Area: Inspect seals and surfaces of propeller and gearleg for marine growth buildup; clean and apply anti-fouling paint before each seasonCheck: Inspect seals and surfaces of propeller and gearleg for marine growth buildup; clean and apply anti-fouling paint before each season
- Area: Check zinc anode for corrosion; replace when half of anode has eroded or before each seasonCheck: Check zinc anode for corrosion; replace when half of anode has eroded or before each season
- Area: Verify all electrical connections are clean, firmly fastened, and free from corrosion or moistureCheck: Verify all electrical connections are clean, firmly fastened, and free from corrosion or moisture
- Area: Inspect tunnel interior and surrounding boat hull area for water intrusion, oil leaks, or signs of damageCheck: Inspect tunnel interior and surrounding boat hull area for water intrusion, oil leaks, or signs of damage
- Area: Test motor operation with full thrust cycles; ensure smooth operation without grinding or unusual noiseCheck: Test motor operation with full thrust cycles; ensure smooth operation without grinding or unusual noise
- Area: Verify galvanic isolation integrity and test electrical continuity of protective systemsCheck: Verify galvanic isolation integrity and test electrical continuity of protective systems
- Area: Inspect ceramic seals and sealed drive lubrication system for leaks; ensure gearleg remains properly sealedCheck: Inspect ceramic seals and sealed drive lubrication system for leaks; ensure gearleg remains properly sealed
- Area: Check propeller blades for damage, deformation, or imbalance that could affect thrust performanceCheck: Check propeller blades for damage, deformation, or imbalance that could affect thrust performance
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
E210/250TC-24V
✓ verified
Application
eVision tunnel bow/stern thruster with variable speed control and ignition protection for motor and sailboats 55-78 feet
Common Failures & Inspection Points
- Area: Inspect seals and surfaces of propeller and gearleg for marine growth buildup; clean and apply anti-fouling paint before each seasonCheck: Inspect seals and surfaces of propeller and gearleg for marine growth buildup; clean and apply anti-fouling paint before each season
- Area: Check zinc anode for corrosion; replace when half of anode has eroded or before each seasonCheck: Check zinc anode for corrosion; replace when half of anode has eroded or before each season
- Area: Verify all electrical connections are clean, firmly fastened, and free from corrosion or moistureCheck: Verify all electrical connections are clean, firmly fastened, and free from corrosion or moisture
- Area: Inspect tunnel interior and surrounding boat hull area for water intrusion, oil leaks, or signs of damageCheck: Inspect tunnel interior and surrounding boat hull area for water intrusion, oil leaks, or signs of damage
- Area: Test motor operation with full thrust cycles; ensure smooth operation without grinding or unusual noiseCheck: Test motor operation with full thrust cycles; ensure smooth operation without grinding or unusual noise
- Area: Verify galvanic isolation integrity and test electrical continuity of protective systemsCheck: Verify galvanic isolation integrity and test electrical continuity of protective systems
- Area: Inspect ceramic seals and sealed drive lubrication system for leaks; ensure gearleg remains properly sealedCheck: Inspect ceramic seals and sealed drive lubrication system for leaks; ensure gearleg remains properly sealed
- Area: Check propeller blades for damage, deformation, or imbalance that could affect thrust performanceCheck: Check propeller blades for damage, deformation, or imbalance that could affect thrust performance
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
E210/250TC-48V
✓ verified
Application
eVision tunnel bow/stern thruster with variable speed control and ignition protection for motor and sailboats 55-78 feet
Common Failures & Inspection Points
- Area: Inspect seals and surfaces of propeller and gearleg for marine growth buildup; clean and apply anti-fouling paint before each seasonCheck: Inspect seals and surfaces of propeller and gearleg for marine growth buildup; clean and apply anti-fouling paint before each season
- Area: Check zinc anode for corrosion; replace when half of anode has eroded or before each seasonCheck: Check zinc anode for corrosion; replace when half of anode has eroded or before each season
- Area: Verify all electrical connections are clean, firmly fastened, and free from corrosion or moistureCheck: Verify all electrical connections are clean, firmly fastened, and free from corrosion or moisture
- Area: Inspect tunnel interior and surrounding boat hull area for water intrusion, oil leaks, or signs of damageCheck: Inspect tunnel interior and surrounding boat hull area for water intrusion, oil leaks, or signs of damage
- Area: Test motor operation with full thrust cycles; ensure smooth operation without grinding or unusual noiseCheck: Test motor operation with full thrust cycles; ensure smooth operation without grinding or unusual noise
- Area: Verify galvanic isolation integrity and test electrical continuity of protective systemsCheck: Verify galvanic isolation integrity and test electrical continuity of protective systems
- Area: Inspect ceramic seals and sealed drive lubrication system for leaks; ensure gearleg remains properly sealedCheck: Inspect ceramic seals and sealed drive lubrication system for leaks; ensure gearleg remains properly sealed
- Area: Check propeller blades for damage, deformation, or imbalance that could affect thrust performanceCheck: Check propeller blades for damage, deformation, or imbalance that could affect thrust performance
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
E240/250TC-48V
✓ verified
Application
eVision tunnel bow/stern thruster with variable speed control and ignition protection for motor and sailboats 55-78 feet
Common Failures & Inspection Points
- Area: Inspect seals and surfaces of propeller and gearleg for marine growth buildup; clean and apply anti-fouling paint before each seasonCheck: Inspect seals and surfaces of propeller and gearleg for marine growth buildup; clean and apply anti-fouling paint before each season
- Area: Check zinc anode for corrosion; replace when half of anode has eroded or before each seasonCheck: Check zinc anode for corrosion; replace when half of anode has eroded or before each season
- Area: Verify all electrical connections are clean, firmly fastened, and free from corrosion or moistureCheck: Verify all electrical connections are clean, firmly fastened, and free from corrosion or moisture
- Area: Inspect tunnel interior and surrounding boat hull area for water intrusion, oil leaks, or signs of damageCheck: Inspect tunnel interior and surrounding boat hull area for water intrusion, oil leaks, or signs of damage
- Area: Test motor operation with full thrust cycles; ensure smooth operation without grinding or unusual noiseCheck: Test motor operation with full thrust cycles; ensure smooth operation without grinding or unusual noise
- Area: Verify galvanic isolation integrity and test electrical continuity of protective systemsCheck: Verify galvanic isolation integrity and test electrical continuity of protective systems
- Area: Inspect ceramic seals and sealed drive lubrication system for leaks; ensure gearleg remains properly sealedCheck: Inspect ceramic seals and sealed drive lubrication system for leaks; ensure gearleg remains properly sealed
- Area: Check propeller blades for damage, deformation, or imbalance that could affect thrust performanceCheck: Check propeller blades for damage, deformation, or imbalance that could affect thrust performance
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
E300/300TC-48V
✓ verified
Application
eVision tunnel bow/stern thruster with variable speed control and ignition protection for motor and sailboats 59-95 feet
Common Failures & Inspection Points
- Area: Inspect seals and surfaces of propeller and gearleg for marine growth buildup; clean and apply anti-fouling paint before each seasonCheck: Inspect seals and surfaces of propeller and gearleg for marine growth buildup; clean and apply anti-fouling paint before each season
- Area: Check zinc anode for corrosion; replace when half of anode has eroded or before each seasonCheck: Check zinc anode for corrosion; replace when half of anode has eroded or before each season
- Area: Verify all electrical connections are clean, firmly fastened, and free from corrosion or moistureCheck: Verify all electrical connections are clean, firmly fastened, and free from corrosion or moisture
- Area: Inspect tunnel interior and surrounding boat hull area for water intrusion, oil leaks, or signs of damageCheck: Inspect tunnel interior and surrounding boat hull area for water intrusion, oil leaks, or signs of damage
- Area: Test motor operation with full thrust cycles; ensure smooth operation without grinding or unusual noiseCheck: Test motor operation with full thrust cycles; ensure smooth operation without grinding or unusual noise
- Area: Verify galvanic isolation integrity and test electrical continuity of protective systemsCheck: Verify galvanic isolation integrity and test electrical continuity of protective systems
- Area: Inspect ceramic seals and sealed drive lubrication system for leaks; ensure gearleg remains properly sealedCheck: Inspect ceramic seals and sealed drive lubrication system for leaks; ensure gearleg remains properly sealed
- Area: Check propeller blades for damage, deformation, or imbalance that could affect thrust performanceCheck: Check propeller blades for damage, deformation, or imbalance that could affect thrust performance
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
Brunvoll AS
10 ✓ 10 verified
FU 84
✓ verified
Application
Tunnel thruster - bow/stern maneuvering
Common Failures & Inspection Points
- Area: Inspect thruster tunnel space twice yearly for moisture, standing water, and leaksCheck: Inspect thruster tunnel space twice yearly for moisture, standing water, and leaks
- Area: Examine tunnel ends for cracks in gelcoat or laminate, check gasket seals for leaksCheck: Examine tunnel ends for cracks in gelcoat or laminate, check gasket seals for leaks
- Area: Clean thruster drive, propeller(s) and tunnel interior of marine growth and inspect for cracks or damageCheck: Clean thruster drive, propeller(s) and tunnel interior of marine growth and inspect for cracks or damage
- Area: Check for oil beneath propeller indicating seal leakage requiring replacementCheck: Check for oil beneath propeller indicating seal leakage requiring replacement
- Area: Inspect and renew sacrificial anodes (zincs) annually minimum, more frequently depending on vessel locationCheck: Inspect and renew sacrificial anodes (zincs) annually minimum, more frequently depending on vessel location
- Area: Verify condition of helm control panels and joysticks for looseness, corrosion, UV damageCheck: Verify condition of helm control panels and joysticks for looseness, corrosion, UV damage
- Area: Check motor function and verify electrical/hydraulic supply lines, grease moving partsCheck: Check motor function and verify electrical/hydraulic supply lines, grease moving parts
- Area: Inspect gearbox, propeller connections, and shear pins for wear, especially with frequent useCheck: Inspect gearbox, propeller connections, and shear pins for wear, especially with frequent use
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
FU 105
✓ verified
Application
Tunnel thruster - bow/stern maneuvering
Common Failures & Inspection Points
- Area: Inspect thruster tunnel space twice yearly for moisture, standing water, and leaksCheck: Inspect thruster tunnel space twice yearly for moisture, standing water, and leaks
- Area: Examine tunnel ends for cracks in gelcoat or laminate, check gasket seals for leaksCheck: Examine tunnel ends for cracks in gelcoat or laminate, check gasket seals for leaks
- Area: Clean thruster drive, propeller(s) and tunnel interior of marine growth and inspect for cracks or damageCheck: Clean thruster drive, propeller(s) and tunnel interior of marine growth and inspect for cracks or damage
- Area: Check for oil beneath propeller indicating seal leakage requiring replacementCheck: Check for oil beneath propeller indicating seal leakage requiring replacement
- Area: Inspect and renew sacrificial anodes (zincs) annually minimum, more frequently depending on vessel locationCheck: Inspect and renew sacrificial anodes (zincs) annually minimum, more frequently depending on vessel location
- Area: Verify condition of helm control panels and joysticks for looseness, corrosion, UV damageCheck: Verify condition of helm control panels and joysticks for looseness, corrosion, UV damage
- Area: Check motor function and verify electrical/hydraulic supply lines, grease moving partsCheck: Check motor function and verify electrical/hydraulic supply lines, grease moving parts
- Area: Inspect gearbox, propeller connections, and shear pins for wear, especially with frequent useCheck: Inspect gearbox, propeller connections, and shear pins for wear, especially with frequent use
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
FU 125
✓ verified
Application
Tunnel thruster - large vessel maneuvering
Common Failures & Inspection Points
- Area: Inspect thruster tunnel space twice yearly for moisture, standing water, and leaksCheck: Inspect thruster tunnel space twice yearly for moisture, standing water, and leaks
- Area: Examine tunnel ends for cracks in gelcoat or laminate, check gasket seals for leaksCheck: Examine tunnel ends for cracks in gelcoat or laminate, check gasket seals for leaks
- Area: Clean thruster drive, propeller(s) and tunnel interior of marine growth and inspect for cracks or damageCheck: Clean thruster drive, propeller(s) and tunnel interior of marine growth and inspect for cracks or damage
- Area: Check for oil beneath propeller indicating seal leakage requiring replacementCheck: Check for oil beneath propeller indicating seal leakage requiring replacement
- Area: Inspect and renew sacrificial anodes (zincs) annually minimum, more frequently depending on vessel locationCheck: Inspect and renew sacrificial anodes (zincs) annually minimum, more frequently depending on vessel location
- Area: Verify condition of helm control panels and joysticks for looseness, corrosion, UV damageCheck: Verify condition of helm control panels and joysticks for looseness, corrosion, UV damage
- Area: Check motor function and verify electrical/hydraulic supply lines, grease moving partsCheck: Check motor function and verify electrical/hydraulic supply lines, grease moving parts
- Area: Inspect gearbox, propeller connections, and shear pins for wear, especially with frequent useCheck: Inspect gearbox, propeller connections, and shear pins for wear, especially with frequent use
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
FU 135
✓ verified
Application
Tunnel thruster - large cruise vessels
Common Failures & Inspection Points
- Area: Inspect thruster tunnel space twice yearly for moisture, standing water, and leaksCheck: Inspect thruster tunnel space twice yearly for moisture, standing water, and leaks
- Area: Examine tunnel ends for cracks in gelcoat or laminate, check gasket seals for leaksCheck: Examine tunnel ends for cracks in gelcoat or laminate, check gasket seals for leaks
- Area: Clean thruster drive, propeller(s) and tunnel interior of marine growth and inspect for cracks or damageCheck: Clean thruster drive, propeller(s) and tunnel interior of marine growth and inspect for cracks or damage
- Area: Check for oil beneath propeller indicating seal leakage requiring replacementCheck: Check for oil beneath propeller indicating seal leakage requiring replacement
- Area: Inspect and renew sacrificial anodes (zincs) annually minimum, more frequently depending on vessel locationCheck: Inspect and renew sacrificial anodes (zincs) annually minimum, more frequently depending on vessel location
- Area: Verify condition of helm control panels and joysticks for looseness, corrosion, UV damageCheck: Verify condition of helm control panels and joysticks for looseness, corrosion, UV damage
- Area: Check motor function and verify electrical/hydraulic supply lines, grease moving partsCheck: Check motor function and verify electrical/hydraulic supply lines, grease moving parts
- Area: Inspect gearbox, propeller connections, and shear pins for wear, especially with frequent useCheck: Inspect gearbox, propeller connections, and shear pins for wear, especially with frequent use
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
RDT 800
✓ verified
Application
Rim driven tunnel thruster - compact electric design
Common Failures & Inspection Points
- Area: Inspect thruster tunnel space twice yearly for moisture, standing water, and leaksCheck: Inspect thruster tunnel space twice yearly for moisture, standing water, and leaks
- Area: Examine tunnel ends for cracks in gelcoat or laminate, check gasket seals for leaksCheck: Examine tunnel ends for cracks in gelcoat or laminate, check gasket seals for leaks
- Area: Clean thruster drive, propeller(s) and tunnel interior of marine growth and inspect for cracks or damageCheck: Clean thruster drive, propeller(s) and tunnel interior of marine growth and inspect for cracks or damage
- Area: Check for oil beneath propeller indicating seal leakage requiring replacementCheck: Check for oil beneath propeller indicating seal leakage requiring replacement
- Area: Inspect and renew sacrificial anodes (zincs) annually minimum, more frequently depending on vessel locationCheck: Inspect and renew sacrificial anodes (zincs) annually minimum, more frequently depending on vessel location
- Area: Verify condition of helm control panels and joysticks for looseness, corrosion, UV damageCheck: Verify condition of helm control panels and joysticks for looseness, corrosion, UV damage
- Area: Check motor function and verify electrical/hydraulic supply lines, grease moving partsCheck: Check motor function and verify electrical/hydraulic supply lines, grease moving parts
- Area: Inspect gearbox, propeller connections, and shear pins for wear, especially with frequent useCheck: Inspect gearbox, propeller connections, and shear pins for wear, especially with frequent use
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
RDT 1000
✓ verified
Application
Rim driven tunnel thruster - compact electric design
Common Failures & Inspection Points
- Area: Inspect thruster tunnel space twice yearly for moisture, standing water, and leaksCheck: Inspect thruster tunnel space twice yearly for moisture, standing water, and leaks
- Area: Examine tunnel ends for cracks in gelcoat or laminate, check gasket seals for leaksCheck: Examine tunnel ends for cracks in gelcoat or laminate, check gasket seals for leaks
- Area: Clean thruster drive, propeller(s) and tunnel interior of marine growth and inspect for cracks or damageCheck: Clean thruster drive, propeller(s) and tunnel interior of marine growth and inspect for cracks or damage
- Area: Check for oil beneath propeller indicating seal leakage requiring replacementCheck: Check for oil beneath propeller indicating seal leakage requiring replacement
- Area: Inspect and renew sacrificial anodes (zincs) annually minimum, more frequently depending on vessel locationCheck: Inspect and renew sacrificial anodes (zincs) annually minimum, more frequently depending on vessel location
- Area: Verify condition of helm control panels and joysticks for looseness, corrosion, UV damageCheck: Verify condition of helm control panels and joysticks for looseness, corrosion, UV damage
- Area: Check motor function and verify electrical/hydraulic supply lines, grease moving partsCheck: Check motor function and verify electrical/hydraulic supply lines, grease moving parts
- Area: Inspect gearbox, propeller connections, and shear pins for wear, especially with frequent useCheck: Inspect gearbox, propeller connections, and shear pins for wear, especially with frequent use
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
RDT 1250
✓ verified
Application
Rim driven tunnel thruster - compact electric design
Common Failures & Inspection Points
- Area: Inspect thruster tunnel space twice yearly for moisture, standing water, and leaksCheck: Inspect thruster tunnel space twice yearly for moisture, standing water, and leaks
- Area: Examine tunnel ends for cracks in gelcoat or laminate, check gasket seals for leaksCheck: Examine tunnel ends for cracks in gelcoat or laminate, check gasket seals for leaks
- Area: Clean thruster drive, propeller(s) and tunnel interior of marine growth and inspect for cracks or damageCheck: Clean thruster drive, propeller(s) and tunnel interior of marine growth and inspect for cracks or damage
- Area: Check for oil beneath propeller indicating seal leakage requiring replacementCheck: Check for oil beneath propeller indicating seal leakage requiring replacement
- Area: Inspect and renew sacrificial anodes (zincs) annually minimum, more frequently depending on vessel locationCheck: Inspect and renew sacrificial anodes (zincs) annually minimum, more frequently depending on vessel location
- Area: Verify condition of helm control panels and joysticks for looseness, corrosion, UV damageCheck: Verify condition of helm control panels and joysticks for looseness, corrosion, UV damage
- Area: Check motor function and verify electrical/hydraulic supply lines, grease moving partsCheck: Check motor function and verify electrical/hydraulic supply lines, grease moving parts
- Area: Inspect gearbox, propeller connections, and shear pins for wear, especially with frequent useCheck: Inspect gearbox, propeller connections, and shear pins for wear, especially with frequent use
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
RDT 1500
✓ verified
Application
Rim driven tunnel thruster - compact electric design
Common Failures & Inspection Points
- Area: Inspect thruster tunnel space twice yearly for moisture, standing water, and leaksCheck: Inspect thruster tunnel space twice yearly for moisture, standing water, and leaks
- Area: Examine tunnel ends for cracks in gelcoat or laminate, check gasket seals for leaksCheck: Examine tunnel ends for cracks in gelcoat or laminate, check gasket seals for leaks
- Area: Clean thruster drive, propeller(s) and tunnel interior of marine growth and inspect for cracks or damageCheck: Clean thruster drive, propeller(s) and tunnel interior of marine growth and inspect for cracks or damage
- Area: Check for oil beneath propeller indicating seal leakage requiring replacementCheck: Check for oil beneath propeller indicating seal leakage requiring replacement
- Area: Inspect and renew sacrificial anodes (zincs) annually minimum, more frequently depending on vessel locationCheck: Inspect and renew sacrificial anodes (zincs) annually minimum, more frequently depending on vessel location
- Area: Verify condition of helm control panels and joysticks for looseness, corrosion, UV damageCheck: Verify condition of helm control panels and joysticks for looseness, corrosion, UV damage
- Area: Check motor function and verify electrical/hydraulic supply lines, grease moving partsCheck: Check motor function and verify electrical/hydraulic supply lines, grease moving parts
- Area: Inspect gearbox, propeller connections, and shear pins for wear, especially with frequent useCheck: Inspect gearbox, propeller connections, and shear pins for wear, especially with frequent use
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
RDT 1800
✓ verified
Application
Rim driven tunnel thruster - compact electric design
Common Failures & Inspection Points
- Area: Inspect thruster tunnel space twice yearly for moisture, standing water, and leaksCheck: Inspect thruster tunnel space twice yearly for moisture, standing water, and leaks
- Area: Examine tunnel ends for cracks in gelcoat or laminate, check gasket seals for leaksCheck: Examine tunnel ends for cracks in gelcoat or laminate, check gasket seals for leaks
- Area: Clean thruster drive, propeller(s) and tunnel interior of marine growth and inspect for cracks or damageCheck: Clean thruster drive, propeller(s) and tunnel interior of marine growth and inspect for cracks or damage
- Area: Check for oil beneath propeller indicating seal leakage requiring replacementCheck: Check for oil beneath propeller indicating seal leakage requiring replacement
- Area: Inspect and renew sacrificial anodes (zincs) annually minimum, more frequently depending on vessel locationCheck: Inspect and renew sacrificial anodes (zincs) annually minimum, more frequently depending on vessel location
- Area: Verify condition of helm control panels and joysticks for looseness, corrosion, UV damageCheck: Verify condition of helm control panels and joysticks for looseness, corrosion, UV damage
- Area: Check motor function and verify electrical/hydraulic supply lines, grease moving partsCheck: Check motor function and verify electrical/hydraulic supply lines, grease moving parts
- Area: Inspect gearbox, propeller connections, and shear pins for wear, especially with frequent useCheck: Inspect gearbox, propeller connections, and shear pins for wear, especially with frequent use
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
RDT 2100
✓ verified
Application
Rim driven tunnel thruster - compact electric design
Common Failures & Inspection Points
- Area: Inspect thruster tunnel space twice yearly for moisture, standing water, and leaksCheck: Inspect thruster tunnel space twice yearly for moisture, standing water, and leaks
- Area: Examine tunnel ends for cracks in gelcoat or laminate, check gasket seals for leaksCheck: Examine tunnel ends for cracks in gelcoat or laminate, check gasket seals for leaks
- Area: Clean thruster drive, propeller(s) and tunnel interior of marine growth and inspect for cracks or damageCheck: Clean thruster drive, propeller(s) and tunnel interior of marine growth and inspect for cracks or damage
- Area: Check for oil beneath propeller indicating seal leakage requiring replacementCheck: Check for oil beneath propeller indicating seal leakage requiring replacement
- Area: Inspect and renew sacrificial anodes (zincs) annually minimum, more frequently depending on vessel locationCheck: Inspect and renew sacrificial anodes (zincs) annually minimum, more frequently depending on vessel location
- Area: Verify condition of helm control panels and joysticks for looseness, corrosion, UV damageCheck: Verify condition of helm control panels and joysticks for looseness, corrosion, UV damage
- Area: Check motor function and verify electrical/hydraulic supply lines, grease moving partsCheck: Check motor function and verify electrical/hydraulic supply lines, grease moving parts
- Area: Inspect gearbox, propeller connections, and shear pins for wear, especially with frequent useCheck: Inspect gearbox, propeller connections, and shear pins for wear, especially with frequent use
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
Kongsberg Maritime
5 ✓ 5 verified
Type TT (Standard Tunnel Thruster)
✓ verified
Application
Auxiliary propulsion, Dynamic Positioning (DP), bow and stern installations
Common Failures & Inspection Points
- Area: Propeller blade tip clearance to tunnel plating and inspection for erosion/paint lossCheck: Propeller blade tip clearance to tunnel plating and inspection for erosion/paint loss
- Area: Propeller shaft seals and elastomer O-ring condition (renewal interval: 5-year)Check: Propeller shaft seals and elastomer O-ring condition (renewal interval: 5-year)
- Area: Bearing clearances and roller bearing wear assessment; gear tooth pattern inspectionCheck: Bearing clearances and roller bearing wear assessment; gear tooth pattern inspection
- Area: Gearbox/hydraulic oil analysis and fluid condition; EAL (Environmentally Acceptable Lubricant) compatibility verificationCheck: Gearbox/hydraulic oil analysis and fluid condition; EAL (Environmentally Acceptable Lubricant) compatibility verification
- Area: Electric motor stator/rotor condition, vibration levels, temperature monitoring, and spin testing verificationCheck: Electric motor stator/rotor condition, vibration levels, temperature monitoring, and spin testing verification
- Area: Drive module accessibility and intermediate shaft/coupler inspection for wear or misalignmentCheck: Drive module accessibility and intermediate shaft/coupler inspection for wear or misalignment
- Area: Pitch change control mechanism operational testing (for CP variants) and control system validationCheck: Pitch change control mechanism operational testing (for CP variants) and control system validation
- Area: Tunnel structure integrity assessment for cavitation erosion, corrosion, and fatigue crackingCheck: Tunnel structure integrity assessment for cavitation erosion, corrosion, and fatigue cracking
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
Type TTH (Harmonised Series)
✓ verified
Application
Dynamic Positioning (DP), Auxiliary (Aux) propulsion, bow and stern, Polar Class 6 and 7 certified
Common Failures & Inspection Points
- Area: Propeller blade tip clearance to tunnel plating and inspection for erosion/paint lossCheck: Propeller blade tip clearance to tunnel plating and inspection for erosion/paint loss
- Area: Propeller shaft seals and elastomer O-ring condition (renewal interval: 5-year)Check: Propeller shaft seals and elastomer O-ring condition (renewal interval: 5-year)
- Area: Bearing clearances and roller bearing wear assessment; gear tooth pattern inspectionCheck: Bearing clearances and roller bearing wear assessment; gear tooth pattern inspection
- Area: Gearbox/hydraulic oil analysis and fluid condition; EAL (Environmentally Acceptable Lubricant) compatibility verificationCheck: Gearbox/hydraulic oil analysis and fluid condition; EAL (Environmentally Acceptable Lubricant) compatibility verification
- Area: Electric motor stator/rotor condition, vibration levels, temperature monitoring, and spin testing verificationCheck: Electric motor stator/rotor condition, vibration levels, temperature monitoring, and spin testing verification
- Area: Drive module accessibility and intermediate shaft/coupler inspection for wear or misalignmentCheck: Drive module accessibility and intermediate shaft/coupler inspection for wear or misalignment
- Area: Pitch change control mechanism operational testing (for CP variants) and control system validationCheck: Pitch change control mechanism operational testing (for CP variants) and control system validation
- Area: Tunnel structure integrity assessment for cavitation erosion, corrosion, and fatigue crackingCheck: Tunnel structure integrity assessment for cavitation erosion, corrosion, and fatigue cracking
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
Type TT POLAR (Ice-Class Reinforced)
✓ verified
Application
High ice-class vessels, Polar ice operations above PC6, bow and stern propulsion
Common Failures & Inspection Points
- Area: Propeller blade tip clearance to tunnel plating and inspection for erosion/paint lossCheck: Propeller blade tip clearance to tunnel plating and inspection for erosion/paint loss
- Area: Propeller shaft seals and elastomer O-ring condition (renewal interval: 5-year)Check: Propeller shaft seals and elastomer O-ring condition (renewal interval: 5-year)
- Area: Bearing clearances and roller bearing wear assessment; gear tooth pattern inspectionCheck: Bearing clearances and roller bearing wear assessment; gear tooth pattern inspection
- Area: Gearbox/hydraulic oil analysis and fluid condition; EAL (Environmentally Acceptable Lubricant) compatibility verificationCheck: Gearbox/hydraulic oil analysis and fluid condition; EAL (Environmentally Acceptable Lubricant) compatibility verification
- Area: Electric motor stator/rotor condition, vibration levels, temperature monitoring, and spin testing verificationCheck: Electric motor stator/rotor condition, vibration levels, temperature monitoring, and spin testing verification
- Area: Drive module accessibility and intermediate shaft/coupler inspection for wear or misalignmentCheck: Drive module accessibility and intermediate shaft/coupler inspection for wear or misalignment
- Area: Pitch change control mechanism operational testing (for CP variants) and control system validationCheck: Pitch change control mechanism operational testing (for CP variants) and control system validation
- Area: Tunnel structure integrity assessment for cavitation erosion, corrosion, and fatigue crackingCheck: Tunnel structure integrity assessment for cavitation erosion, corrosion, and fatigue cracking
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
RD-TT 1600 (Rim Drive Tunnel Thruster)
✓ verified
Application
Dynamic positioning vessels, offshore supply vessels, ferries, cruise ships, research vessels
Common Failures & Inspection Points
- Area: Propeller blade tip clearance to tunnel plating and inspection for erosion/paint lossCheck: Propeller blade tip clearance to tunnel plating and inspection for erosion/paint loss
- Area: Propeller shaft seals and elastomer O-ring condition (renewal interval: 5-year)Check: Propeller shaft seals and elastomer O-ring condition (renewal interval: 5-year)
- Area: Bearing clearances and roller bearing wear assessment; gear tooth pattern inspectionCheck: Bearing clearances and roller bearing wear assessment; gear tooth pattern inspection
- Area: Gearbox/hydraulic oil analysis and fluid condition; EAL (Environmentally Acceptable Lubricant) compatibility verificationCheck: Gearbox/hydraulic oil analysis and fluid condition; EAL (Environmentally Acceptable Lubricant) compatibility verification
- Area: Electric motor stator/rotor condition, vibration levels, temperature monitoring, and spin testing verificationCheck: Electric motor stator/rotor condition, vibration levels, temperature monitoring, and spin testing verification
- Area: Drive module accessibility and intermediate shaft/coupler inspection for wear or misalignmentCheck: Drive module accessibility and intermediate shaft/coupler inspection for wear or misalignment
- Area: Pitch change control mechanism operational testing (for CP variants) and control system validationCheck: Pitch change control mechanism operational testing (for CP variants) and control system validation
- Area: Tunnel structure integrity assessment for cavitation erosion, corrosion, and fatigue crackingCheck: Tunnel structure integrity assessment for cavitation erosion, corrosion, and fatigue cracking
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
RD-TT 2000 (Rim Drive Tunnel Thruster)
✓ verified
Application
Dynamic positioning vessels, offshore supply vessels, ferries, cruise ships, research vessels
Common Failures & Inspection Points
- Area: Propeller blade tip clearance to tunnel plating and inspection for erosion/paint lossCheck: Propeller blade tip clearance to tunnel plating and inspection for erosion/paint loss
- Area: Propeller shaft seals and elastomer O-ring condition (renewal interval: 5-year)Check: Propeller shaft seals and elastomer O-ring condition (renewal interval: 5-year)
- Area: Bearing clearances and roller bearing wear assessment; gear tooth pattern inspectionCheck: Bearing clearances and roller bearing wear assessment; gear tooth pattern inspection
- Area: Gearbox/hydraulic oil analysis and fluid condition; EAL (Environmentally Acceptable Lubricant) compatibility verificationCheck: Gearbox/hydraulic oil analysis and fluid condition; EAL (Environmentally Acceptable Lubricant) compatibility verification
- Area: Electric motor stator/rotor condition, vibration levels, temperature monitoring, and spin testing verificationCheck: Electric motor stator/rotor condition, vibration levels, temperature monitoring, and spin testing verification
- Area: Drive module accessibility and intermediate shaft/coupler inspection for wear or misalignmentCheck: Drive module accessibility and intermediate shaft/coupler inspection for wear or misalignment
- Area: Pitch change control mechanism operational testing (for CP variants) and control system validationCheck: Pitch change control mechanism operational testing (for CP variants) and control system validation
- Area: Tunnel structure integrity assessment for cavitation erosion, corrosion, and fatigue crackingCheck: Tunnel structure integrity assessment for cavitation erosion, corrosion, and fatigue cracking
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
Steerprop
5 ✓ 5 verified
SP 10 TT
✓ verified
Application
Tunnel Thruster - Auxiliary propulsion for wind installation vessels, dynamic positioning
Common Failures & Inspection Points
- Area: Propeller blade condition and pitch angle (fixed pitch propeller inspection for wear, cracks, and erosion)Check: Propeller blade condition and pitch angle (fixed pitch propeller inspection for wear, cracks, and erosion)
- Area: Tunnel bearing system integrity and lubrication statusCheck: Tunnel bearing system integrity and lubrication status
- Area: Motor/drive unit electrical insulation and winding conditionCheck: Motor/drive unit electrical insulation and winding condition
- Area: Gearbox oil level, condition, and cooler functionalityCheck: Gearbox oil level, condition, and cooler functionality
- Area: Thrust bearing and stern tube bearing wear and clearancesCheck: Thrust bearing and stern tube bearing wear and clearances
- Area: Hull tunnel opening and strut structural integrity (no cracks, corrosion, or deformation)Check: Hull tunnel opening and strut structural integrity (no cracks, corrosion, or deformation)
- Area: Vibration and noise levels during operation (baseline comparison)Check: Vibration and noise levels during operation (baseline comparison)
- Area: Sealing system functionality (lip seals, shaft seals against water ingress)Check: Sealing system functionality (lip seals, shaft seals against water ingress)
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
SP 25 TT
✓ verified
Application
Tunnel Thruster - Auxiliary propulsion for field support vessels
Common Failures & Inspection Points
- Area: Propeller blade condition and pitch angle (fixed pitch propeller inspection for wear, cracks, and erosion)Check: Propeller blade condition and pitch angle (fixed pitch propeller inspection for wear, cracks, and erosion)
- Area: Tunnel bearing system integrity and lubrication statusCheck: Tunnel bearing system integrity and lubrication status
- Area: Motor/drive unit electrical insulation and winding conditionCheck: Motor/drive unit electrical insulation and winding condition
- Area: Gearbox oil level, condition, and cooler functionalityCheck: Gearbox oil level, condition, and cooler functionality
- Area: Thrust bearing and stern tube bearing wear and clearancesCheck: Thrust bearing and stern tube bearing wear and clearances
- Area: Hull tunnel opening and strut structural integrity (no cracks, corrosion, or deformation)Check: Hull tunnel opening and strut structural integrity (no cracks, corrosion, or deformation)
- Area: Vibration and noise levels during operation (baseline comparison)Check: Vibration and noise levels during operation (baseline comparison)
- Area: Sealing system functionality (lip seals, shaft seals against water ingress)Check: Sealing system functionality (lip seals, shaft seals against water ingress)
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
SP 25 TT ARC
✓ verified
Application
Tunnel Thruster - Arctic/ice-class auxiliary propulsion for multi-purpose icebreakers
Common Failures & Inspection Points
- Area: Propeller blade condition and pitch angle (fixed pitch propeller inspection for wear, cracks, and erosion)Check: Propeller blade condition and pitch angle (fixed pitch propeller inspection for wear, cracks, and erosion)
- Area: Tunnel bearing system integrity and lubrication statusCheck: Tunnel bearing system integrity and lubrication status
- Area: Motor/drive unit electrical insulation and winding conditionCheck: Motor/drive unit electrical insulation and winding condition
- Area: Gearbox oil level, condition, and cooler functionalityCheck: Gearbox oil level, condition, and cooler functionality
- Area: Thrust bearing and stern tube bearing wear and clearancesCheck: Thrust bearing and stern tube bearing wear and clearances
- Area: Hull tunnel opening and strut structural integrity (no cracks, corrosion, or deformation)Check: Hull tunnel opening and strut structural integrity (no cracks, corrosion, or deformation)
- Area: Vibration and noise levels during operation (baseline comparison)Check: Vibration and noise levels during operation (baseline comparison)
- Area: Sealing system functionality (lip seals, shaft seals against water ingress)Check: Sealing system functionality (lip seals, shaft seals against water ingress)
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
SP 40 TT
✓ verified
Application
Tunnel Thruster - Heavy-duty auxiliary propulsion for cable-laying vessels and offshore applications
Common Failures & Inspection Points
- Area: Propeller blade condition and pitch angle (fixed pitch propeller inspection for wear, cracks, and erosion)Check: Propeller blade condition and pitch angle (fixed pitch propeller inspection for wear, cracks, and erosion)
- Area: Tunnel bearing system integrity and lubrication statusCheck: Tunnel bearing system integrity and lubrication status
- Area: Motor/drive unit electrical insulation and winding conditionCheck: Motor/drive unit electrical insulation and winding condition
- Area: Gearbox oil level, condition, and cooler functionalityCheck: Gearbox oil level, condition, and cooler functionality
- Area: Thrust bearing and stern tube bearing wear and clearancesCheck: Thrust bearing and stern tube bearing wear and clearances
- Area: Hull tunnel opening and strut structural integrity (no cracks, corrosion, or deformation)Check: Hull tunnel opening and strut structural integrity (no cracks, corrosion, or deformation)
- Area: Vibration and noise levels during operation (baseline comparison)Check: Vibration and noise levels during operation (baseline comparison)
- Area: Sealing system functionality (lip seals, shaft seals against water ingress)Check: Sealing system functionality (lip seals, shaft seals against water ingress)
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
SP 40 TT ARC
✓ verified
Application
Tunnel Thruster - Arctic/ice-class auxiliary propulsion for polar icebreakers (Polar Class 4, Polar Class 2)
Common Failures & Inspection Points
- Area: Propeller blade condition and pitch angle (fixed pitch propeller inspection for wear, cracks, and erosion)Check: Propeller blade condition and pitch angle (fixed pitch propeller inspection for wear, cracks, and erosion)
- Area: Tunnel bearing system integrity and lubrication statusCheck: Tunnel bearing system integrity and lubrication status
- Area: Motor/drive unit electrical insulation and winding conditionCheck: Motor/drive unit electrical insulation and winding condition
- Area: Gearbox oil level, condition, and cooler functionalityCheck: Gearbox oil level, condition, and cooler functionality
- Area: Thrust bearing and stern tube bearing wear and clearancesCheck: Thrust bearing and stern tube bearing wear and clearances
- Area: Hull tunnel opening and strut structural integrity (no cracks, corrosion, or deformation)Check: Hull tunnel opening and strut structural integrity (no cracks, corrosion, or deformation)
- Area: Vibration and noise levels during operation (baseline comparison)Check: Vibration and noise levels during operation (baseline comparison)
- Area: Sealing system functionality (lip seals, shaft seals against water ingress)Check: Sealing system functionality (lip seals, shaft seals against water ingress)
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
Wärtsilä
5 ✓ 2 verified
WTT-40
1500 kW
· 1500.0 kW
· Seawater
· Tunnel thruster with IWSS
Technical Specifications
- Leistungsbereich WST
- 700 kW bis 4900 kW
- Leistungsbereich WTT
- 400 kW bis 5500 kW
- Leistungsbereich WST-R
- 750 kW bis 6500 kW
- Neigungswinkel (WST-R)
- 8-Grad Propeller-Getriebe-Neigung für 15-20% höheren Schub
- Drehbereich
- 360° kontinuierliche Lenkung in horizontaler Ebene
- Wartungsintervalle
- 5-year inspections, 10-year overhauls or after 40,000–56,000 operating hours
- Dichtungstechnologie
- Sternguard In-Water Serviceable Seal (IWSS) - vollständig unter Wasser wartbar
- Ölsystem
- Integrierte Hydraulik mit Feinfiltration zur Lagerverlängerung
Product Lines
- WST - Steerable Thrusters (700-4900 kW)
- WTT - Transverse/Tunnel Thrusters (400-5500 kW)
- WST-R - Retractable Steerable Thrusters (750-6500 kW)
- WST-E - Electric Steerable Thrusters (WST-18E embedded electric)
- Underwater-Mountable Steerable Thrusters
Common Failures & Inspection Points
- Area: Propeller-Blätter: Erosion, Korrosion, Kantenschäden, VerschleißmusterCheck: Perform visual inspection and NDT (non-destructive testing) according to OEM and classification society standards. Polishing in combination with edge damage repair increases operating efficiency by 2-5%. Check for pitting, erosion patterns and corrosion spots; document severe pitting areas.
- Area: Propeller blade foot seals: wear, leakage, water ingressCheck: 5-year overhaul: Disassemble and inspect all seals. 10-year overhaul: Complete replacement of blade foot O-rings. Check for water penetration in jet thruster assembly. Seals are critical for system protection.
- Area: Wellendichtungen (Shaft Seals): Abnutzung, Leckage, AustauschbedarfCheck: Measure propeller shaft wear with poker gauge (between last two stern tube seals). Perform complete inspection of tooth clearance, tooth pattern and shaft seals. 5-year overhaul: seal replacement. 10-year overhaul: comprehensive replacement.
- Area: Bearings (Roller Bearings): wear, bearing clearance, preload, failure symptomsCheck: 5-year overhaul: Check bearing clearance and wear. 10-year overhaul: Complete bearing replacement, reset preload, perform NDT inspection. Check main bearing axial clearance wear with feeler gauge (0.1 mm); maximum wear limit 2 mm. Use Wärtsilä bearing wear measurement system for remote monitoring of propeller shaft shoulder.
- Area: Hydrauliksystem: Öl-Verschmutzung (Wasser, Partikel), Filtration, ÖlqualitätCheck: Check gear oil regularly. At critical wear limits: partial change (bleed-and-feed) or complete oil change. Monitor water content in oil (critical >1000 ppm). Check fine filtration system and redundant filter options. Continuously filter out water ingress. Use all Wärtsilä-approved spare parts. 5-10-year overhaul: Perform oil change and filter maintenance.
- Area: Sternguard In-Water Serviceable Seal (IWSS): seal integrity, maintenance possible underwaterCheck: Check for oil leakage at outer seal. Inspect inflatable emergency seal and inner rope guard. Fully serviceable underwater without habitat or discharge. Measure seal gap and wear. Check retrofit compatibility with other seal types. Confirm compatibility with EAL and mineral oils.
Type-universal inspection/service points for Bow/Stern Thrusters (Wärtsilä, Mega-Schwarm 2026-06). Per-model specs not auto-filled.
Service: Wartsila tunnel thruster; oil analysis every 500 h for water contamination.
Spare Parts: Wärtsilä: Gear oil and seals on board. Lead time: 3-6 weeks.
Strengths
- High thrust capability across a wide power band (400 kW–5.5 MW) suitable for large vessels
- Full 360° horizontal steering improves low‑speed maneuverability and DP performance
- Sternguard IWSS allows seal inspection and replacement under water, reducing dry‑dock time
- Integrated hydraulic drive with fine filtration extends bearing life and reduces oil contamination risk
- Modular design fits both bow and stern installations on new builds or retrofits
Weaknesses
- Requires a hull tunnel; not suitable for vessels without sufficient side space
- Under‑water seal technology demands specialised service personnel and tools
- Noise and vibration levels can be higher than azimuth pod thrusters at comparable power
- Upper power limit (≈5.5 MW) may be lower than some high‑power competitors for ultra‑large ships
- Initial procurement cost is relatively high compared with conventional fixed‑pitch tunnel thrusters
Typical Vessels:
Very Large Crude Carrier (VLCC)Container ship (>8,000 TEU)Cruise linerOffshore supply vesselLNG carrier
Decision Guide: Choose if you need high thrust with full 360° steering, want the ability to service seals underwater and have sufficient hull space for a tunnel thruster. Avoid if hull geometry prevents tunnel installation, you prefer lower noise solutions or require power beyond ~5.5 MW where azimuth pods are more appropriate.
Use Cases: The WTT-40 is typically deployed for precise docking assistance in congested ports, low‑speed maneuvering during offshore operations, and as a backup propulsion element on dynamically positioned vessels that require rapid thrust vector changes.
Wärtsilä transverse or tunnel thrusters WTT
· hydraulic tunnel thruster
Model Number
Wärtsilä Transverse Thruster
Technical Specifications
- Leistungsbereich WST
- 700 kW bis 4900 kW
- Leistungsbereich WTT
- 400 kW bis 5500 kW
- Leistungsbereich WST-R
- 750 kW bis 6500 kW
- Neigungswinkel (WST-R)
- 8-Grad Propeller-Getriebe-Neigung für 15-20% höheren Schub
- Drehbereich
- 360° kontinuierliche Lenkung in horizontaler Ebene
- Wartungsintervalle
- 5-year inspections, 10-year overhauls or after 40,000–56,000 operating hours
- Dichtungstechnologie
- Sternguard In-Water Serviceable Seal (IWSS) - vollständig unter Wasser wartbar
- Ölsystem
- Integrierte Hydraulik mit Feinfiltration zur Lagerverlängerung
Product Lines
- WST - Steerable Thrusters (700-4900 kW)
- WTT - Transverse/Tunnel Thrusters (400-5500 kW)
- WST-R - Retractable Steerable Thrusters (750-6500 kW)
- WST-E - Electric Steerable Thrusters (WST-18E embedded electric)
- Underwater-Mountable Steerable Thrusters
Common Failures & Inspection Points
- Area: Propeller-Blätter: Erosion, Korrosion, Kantenschäden, VerschleißmusterCheck: Perform visual inspection and NDT (non-destructive testing) according to OEM and classification society standards. Polishing in combination with edge damage repair increases operating efficiency by 2-5%. Check for pitting, erosion patterns and corrosion spots; document severe pitting areas.
- Area: Propeller blade foot seals: wear, leakage, water ingressCheck: 5-year overhaul: Disassemble and inspect all seals. 10-year overhaul: Complete replacement of blade foot O-rings. Check for water penetration in jet thruster assembly. Seals are critical for system protection.
- Area: Wellendichtungen (Shaft Seals): Abnutzung, Leckage, AustauschbedarfCheck: Measure propeller shaft wear with poker gauge (between last two stern tube seals). Perform complete inspection of tooth clearance, tooth pattern and shaft seals. 5-year overhaul: seal replacement. 10-year overhaul: comprehensive replacement.
- Area: Bearings (Roller Bearings): wear, bearing clearance, preload, failure symptomsCheck: 5-year overhaul: Check bearing clearance and wear. 10-year overhaul: Complete bearing replacement, reset preload, perform NDT inspection. Check main bearing axial clearance wear with feeler gauge (0.1 mm); maximum wear limit 2 mm. Use Wärtsilä bearing wear measurement system for remote monitoring of propeller shaft shoulder.
- Area: Hydrauliksystem: Öl-Verschmutzung (Wasser, Partikel), Filtration, ÖlqualitätCheck: Check gear oil regularly. At critical wear limits: partial change (bleed-and-feed) or complete oil change. Monitor water content in oil (critical >1000 ppm). Check fine filtration system and redundant filter options. Continuously filter out water ingress. Use all Wärtsilä-approved spare parts. 5-10-year overhaul: Perform oil change and filter maintenance.
- Area: Sternguard In-Water Serviceable Seal (IWSS): seal integrity, maintenance possible underwaterCheck: Check for oil leakage at outer seal. Inspect inflatable emergency seal and inner rope guard. Fully serviceable underwater without habitat or discharge. Measure seal gap and wear. Check retrofit compatibility with other seal types. Confirm compatibility with EAL and mineral oils.
Type-universal inspection/service points for Bow/Stern Thrusters (Wärtsilä, Mega-Schwarm 2026-06). Per-model specs not auto-filled.
Strengths
- Very wide power range (400 kW – 5.5 MW) covering most merchant vessel sizes
- Continuous 360° steering without mechanical gearboxes in the hull
- Sternguard In‑Water Serviceable Seal (IWSS) allows underwater maintenance, reducing dry‑dock time
- Integrated fine‑filtration hydraulic system extends oil life and lowers wear
- Standardised class approvals (DNV, ABS, LR) simplify certification
Weaknesses
- Requires a hull tunnel; installation is invasive and may need structural reinforcement
- Higher capital cost than simple fixed bow thrusters or electric variants
- Hydraulic system adds complexity and needs regular oil quality monitoring
- Seal failure can lead to water ingress into the gear housing if not inspected on schedule
- Retractable option (WST‑R) is not available in the basic WTT line
Typical Vessels:
Crude Oil TankerProduct TankerContainer ShipBulk CarrierCruise ShipOffshore Supply VesselRo‑Ro Ferry
Certifications:
DNV GL Class ApprovalABS ClassificationLloyd's Register Approval
Decision Guide: Choose if you need high thrust with full 360° steering, want to minimise dry‑dock intervals thanks to the IWSS seal, and have sufficient hull space for a tunnel installation. Avoid if vessel design limits tunnel size, budget constraints favour simpler fixed thrusters, or an all‑electric drive is required.
Use Cases: Installed at bow or stern of large merchant ships to aid low‑speed maneuvering in confined ports, support dynamic positioning on offshore vessels, and provide rapid lateral thrust for emergency stopping or docking assistance. Commonly seen on new builds where the tunnel can be integrated during hull construction.
CT/FT125 H
✓ verified
Application
Merchant vessels, cruise vessels, offshore support vessels, offshore construction vessels
Common Failures & Inspection Points
- Area: Thruster compartment and tunnel inspection for marine growth, cracks, corrosion, and overall structural integrity - minimum twice yearlyCheck: Thruster compartment and tunnel inspection for marine growth, cracks, corrosion, and overall structural integrity - minimum twice yearly
- Area: Shaft seals pressure testing and visual inspection for saltwater intrusion indicators (oil leakage into tunnel)Check: Shaft seals pressure testing and visual inspection for saltwater intrusion indicators (oil leakage into tunnel)
- Area: Oil seals and gaskets inspection for leakage or degradation - replace as neededCheck: Oil seals and gaskets inspection for leakage or degradation - replace as needed
- Area: Motor function verification and electrical/hydraulic supply line checksCheck: Motor function verification and electrical/hydraulic supply line checks
- Area: Gearbox backlash measurement and gear wheel condition inspection during overhaulsCheck: Gearbox backlash measurement and gear wheel condition inspection during overhauls
- Area: Blade/propeller inspection for damage, wear, looseness, and proper pitch positioning on controllable pitch unitsCheck: Blade/propeller inspection for damage, wear, looseness, and proper pitch positioning on controllable pitch units
- Area: Bearing condition assessment through vibration monitoring and periodic wear measurement during 5-10 year major overhaulsCheck: Bearing condition assessment through vibration monitoring and periodic wear measurement during 5-10 year major overhauls
- Area: Pod/tunnel interface bolts torque verification and tightening to specificationCheck: Pod/tunnel interface bolts torque verification and tightening to specification
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
[08.08.2026] Datenblattlink entfernt (seite leer): https://www.maritimeinformed.com/w-rtsil-ct-ft125-h-thrusters-technical-details.html
CT/FT150 H
✓ verified
Application
Merchant vessels, cruise vessels, offshore support vessels, offshore construction vessels
Common Failures & Inspection Points
- Area: Thruster compartment and tunnel inspection for marine growth, cracks, corrosion, and overall structural integrity - minimum twice yearlyCheck: Thruster compartment and tunnel inspection for marine growth, cracks, corrosion, and overall structural integrity - minimum twice yearly
- Area: Shaft seals pressure testing and visual inspection for saltwater intrusion indicators (oil leakage into tunnel)Check: Shaft seals pressure testing and visual inspection for saltwater intrusion indicators (oil leakage into tunnel)
- Area: Oil seals and gaskets inspection for leakage or degradation - replace as neededCheck: Oil seals and gaskets inspection for leakage or degradation - replace as needed
- Area: Motor function verification and electrical/hydraulic supply line checksCheck: Motor function verification and electrical/hydraulic supply line checks
- Area: Gearbox backlash measurement and gear wheel condition inspection during overhaulsCheck: Gearbox backlash measurement and gear wheel condition inspection during overhauls
- Area: Blade/propeller inspection for damage, wear, looseness, and proper pitch positioning on controllable pitch unitsCheck: Blade/propeller inspection for damage, wear, looseness, and proper pitch positioning on controllable pitch units
- Area: Bearing condition assessment through vibration monitoring and periodic wear measurement during 5-10 year major overhaulsCheck: Bearing condition assessment through vibration monitoring and periodic wear measurement during 5-10 year major overhauls
- Area: Pod/tunnel interface bolts torque verification and tightening to specificationCheck: Pod/tunnel interface bolts torque verification and tightening to specification
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
[08.08.2026] Datenblattlink entfernt (seite leer): https://www.maritimeinformed.com/w-rtsil-ct-ft150-h-thrusters-technical-details.html
Tunnel Thruster CT/FT
500-5000 kW
· 2000.0 kW
· Seawater
· Electric steerable tunnel thruster
Power (kW)
2000
Type
Tunnel Thruster Electric
Technical Specifications
- Leistungsbereich WST
- 700 kW bis 4900 kW
- Leistungsbereich WTT
- 400 kW bis 5500 kW
- Leistungsbereich WST-R
- 750 kW bis 6500 kW
- Neigungswinkel (WST-R)
- 8-Grad Propeller-Getriebe-Neigung für 15-20% höheren Schub
- Drehbereich
- 360° kontinuierliche Lenkung in horizontaler Ebene
- Wartungsintervalle
- 5-year inspections, 10-year overhauls or after 40,000–56,000 operating hours
- Dichtungstechnologie
- Sternguard In-Water Serviceable Seal (IWSS) - vollständig unter Wasser wartbar
- Ölsystem
- Integrierte Hydraulik mit Feinfiltration zur Lagerverlängerung
Product Lines
- WST - Steerable Thrusters (700-4900 kW)
- WTT - Transverse/Tunnel Thrusters (400-5500 kW)
- WST-R - Retractable Steerable Thrusters (750-6500 kW)
- WST-E - Electric Steerable Thrusters (WST-18E embedded electric)
- Underwater-Mountable Steerable Thrusters
Common Failures & Inspection Points
- Area: Propeller-Blätter: Erosion, Korrosion, Kantenschäden, VerschleißmusterCheck: Perform visual inspection and NDT (non-destructive testing) according to OEM and classification society standards. Polishing in combination with edge damage repair increases operating efficiency by 2-5%. Check for pitting, erosion patterns and corrosion spots; document severe pitting areas.
- Area: Propeller blade foot seals: wear, leakage, water ingressCheck: 5-year overhaul: Disassemble and inspect all seals. 10-year overhaul: Complete replacement of blade foot O-rings. Check for water penetration in jet thruster assembly. Seals are critical for system protection.
- Area: Wellendichtungen (Shaft Seals): Abnutzung, Leckage, AustauschbedarfCheck: Measure propeller shaft wear with poker gauge (between last two stern tube seals). Perform complete inspection of tooth clearance, tooth pattern and shaft seals. 5-year overhaul: seal replacement. 10-year overhaul: comprehensive replacement.
- Area: Bearings (Roller Bearings): wear, bearing clearance, preload, failure symptomsCheck: 5-year overhaul: Check bearing clearance and wear. 10-year overhaul: Complete bearing replacement, reset preload, perform NDT inspection. Check main bearing axial clearance wear with feeler gauge (0.1 mm); maximum wear limit 2 mm. Use Wärtsilä bearing wear measurement system for remote monitoring of propeller shaft shoulder.
- Area: Hydrauliksystem: Öl-Verschmutzung (Wasser, Partikel), Filtration, ÖlqualitätCheck: Check gear oil regularly. At critical wear limits: partial change (bleed-and-feed) or complete oil change. Monitor water content in oil (critical >1000 ppm). Check fine filtration system and redundant filter options. Continuously filter out water ingress. Use all Wärtsilä-approved spare parts. 5-10-year overhaul: Perform oil change and filter maintenance.
- Area: Sternguard In-Water Serviceable Seal (IWSS): seal integrity, maintenance possible underwaterCheck: Check for oil leakage at outer seal. Inspect inflatable emergency seal and inner rope guard. Fully serviceable underwater without habitat or discharge. Measure seal gap and wear. Check retrofit compatibility with other seal types. Confirm compatibility with EAL and mineral oils.
Type-universal inspection/service points for Bow/Stern Thrusters (Wärtsilä, Mega-Schwarm 2026-06). Per-model specs not auto-filled.
Service: Inspect propeller at drydock. Gear oil analysis annually. Motor insulation test annually. Test before arrival at every port.
Spare Parts: Wärtsilä (Lips): gearbox oil and seals on board. Lead time: 3-6 weeks.
Strengths
- Continuous 360° thrust vectoring provides superior low‑speed manoeuvring and dynamic positioning capability.
- Sternguard In‑Water Serviceable Seal allows underwater inspection and minor repairs without dry‑docking, reducing maintenance downtime.
- Integrated hydraulic system with fine filtration extends bearing life and reduces oil contamination risk.
- Modular power range (400 kW – 5.5 MW) covers a wide variety of vessel sizes while maintaining high thrust efficiency.
- Standardised control interface compatible with most DP‑2/DP‑3 systems.
Weaknesses
- Higher capital cost compared with fixed, non‑steerable tunnel thrusters.
- Larger tunnel cross‑section can affect hull structural layout and internal volume.
- Complex control and monitoring electronics require specialised training for crew and shore support.
- Spare parts (e.g., IWSS components) are proprietary, potentially increasing inventory costs.
- Installation requires precise alignment; retrofits on existing vessels may be labour intensive.
Typical Vessels:
Very Large Crude Carriers (VLCC)Ultra‑Large Container ShipsBulk carriers >150 ktCruise shipsOffshore supply and anchor handling tug supply (AHTS) vessels
Certifications:
DNV GL – Approved Marine EquipmentABS – Classification Society ApprovalLloyd's Register – Type Approval
Decision Guide: Choose if you need high thrust for large vessels, require rapid turnaround on thruster maintenance, or operate in ports with tight manoeuvring constraints. Avoid if vessel size and power demand are modest, budget is limited, or hull space cannot accommodate the larger tunnel geometry.
Use Cases: The CT/FT thruster is typically installed on deep‑draft tankers, mega‑container ships and cruise liners to provide precise bow‑and‑stern thrust during docking, undocking and dynamic positioning. It is also favoured on offshore support vessels that need quick directional changes while maintaining station‑keeping in harsh sea states.
Berg Propulsion
4 ✓ 4 verified
SP17
✓ verified
Application
Bow Thruster with adjustable propeller blades
Common Failures & Inspection Points
- Area: Tunnel and compartment inspection for excessive moisture, standing water, and leaks (twice yearly)Check: Tunnel and compartment inspection for excessive moisture, standing water, and leaks (twice yearly)
- Area: Visual inspection of tunnel ends for cracks in gelcoat or laminate where glassed to hullCheck: Visual inspection of tunnel ends for cracks in gelcoat or laminate where glassed to hull
- Area: Gasket inspection at thruster saddle/motor mounting bracket for leaksCheck: Gasket inspection at thruster saddle/motor mounting bracket for leaks
- Area: Propeller and drive inspection for cracks, dings, damage, and loosenessCheck: Propeller and drive inspection for cracks, dings, damage, and looseness
- Area: Oil condition check beneath propeller for leaking seal indicators (monthly sampling for moisture)Check: Oil condition check beneath propeller for leaking seal indicators (monthly sampling for moisture)
- Area: Sacrificial anode (zinc) condition assessment and renewal (minimum annually)Check: Sacrificial anode (zinc) condition assessment and renewal (minimum annually)
- Area: Motor bearing and joint lubrication (monthly)Check: Motor bearing and joint lubrication (monthly)
- Area: Electrical connections and control system testing for corrosion and proper functionCheck: Electrical connections and control system testing for corrosion and proper function
- Area: Gear oil level verification (typically 90-weight) and condition monitoringCheck: Gear oil level verification (typically 90-weight) and condition monitoring
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
MTT111FP
✓ verified
Application
Variable Frequency Drive Tunnel Thruster for Tanker vessels
Common Failures & Inspection Points
- Area: Tunnel and compartment inspection for excessive moisture, standing water, and leaks (twice yearly)Check: Tunnel and compartment inspection for excessive moisture, standing water, and leaks (twice yearly)
- Area: Visual inspection of tunnel ends for cracks in gelcoat or laminate where glassed to hullCheck: Visual inspection of tunnel ends for cracks in gelcoat or laminate where glassed to hull
- Area: Gasket inspection at thruster saddle/motor mounting bracket for leaksCheck: Gasket inspection at thruster saddle/motor mounting bracket for leaks
- Area: Propeller and drive inspection for cracks, dings, damage, and loosenessCheck: Propeller and drive inspection for cracks, dings, damage, and looseness
- Area: Oil condition check beneath propeller for leaking seal indicators (monthly sampling for moisture)Check: Oil condition check beneath propeller for leaking seal indicators (monthly sampling for moisture)
- Area: Sacrificial anode (zinc) condition assessment and renewal (minimum annually)Check: Sacrificial anode (zinc) condition assessment and renewal (minimum annually)
- Area: Motor bearing and joint lubrication (monthly)Check: Motor bearing and joint lubrication (monthly)
- Area: Electrical connections and control system testing for corrosion and proper functionCheck: Electrical connections and control system testing for corrosion and proper function
- Area: Gear oil level verification (typically 90-weight) and condition monitoringCheck: Gear oil level verification (typically 90-weight) and condition monitoring
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
MTT114CP
✓ verified
Application
Controllable-Pitch Bow Thruster for 120-ton Bollard Pull Tug
Common Failures & Inspection Points
- Area: Tunnel and compartment inspection for excessive moisture, standing water, and leaks (twice yearly)Check: Tunnel and compartment inspection for excessive moisture, standing water, and leaks (twice yearly)
- Area: Visual inspection of tunnel ends for cracks in gelcoat or laminate where glassed to hullCheck: Visual inspection of tunnel ends for cracks in gelcoat or laminate where glassed to hull
- Area: Gasket inspection at thruster saddle/motor mounting bracket for leaksCheck: Gasket inspection at thruster saddle/motor mounting bracket for leaks
- Area: Propeller and drive inspection for cracks, dings, damage, and loosenessCheck: Propeller and drive inspection for cracks, dings, damage, and looseness
- Area: Oil condition check beneath propeller for leaking seal indicators (monthly sampling for moisture)Check: Oil condition check beneath propeller for leaking seal indicators (monthly sampling for moisture)
- Area: Sacrificial anode (zinc) condition assessment and renewal (minimum annually)Check: Sacrificial anode (zinc) condition assessment and renewal (minimum annually)
- Area: Motor bearing and joint lubrication (monthly)Check: Motor bearing and joint lubrication (monthly)
- Area: Electrical connections and control system testing for corrosion and proper functionCheck: Electrical connections and control system testing for corrosion and proper function
- Area: Gear oil level verification (typically 90-weight) and condition monitoringCheck: Gear oil level verification (typically 90-weight) and condition monitoring
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
MTT216
✓ verified
Application
Controllable-Pitch Bow Thruster for Diesel-Electric Tugs (60m)
Common Failures & Inspection Points
- Area: Tunnel and compartment inspection for excessive moisture, standing water, and leaks (twice yearly)Check: Tunnel and compartment inspection for excessive moisture, standing water, and leaks (twice yearly)
- Area: Visual inspection of tunnel ends for cracks in gelcoat or laminate where glassed to hullCheck: Visual inspection of tunnel ends for cracks in gelcoat or laminate where glassed to hull
- Area: Gasket inspection at thruster saddle/motor mounting bracket for leaksCheck: Gasket inspection at thruster saddle/motor mounting bracket for leaks
- Area: Propeller and drive inspection for cracks, dings, damage, and loosenessCheck: Propeller and drive inspection for cracks, dings, damage, and looseness
- Area: Oil condition check beneath propeller for leaking seal indicators (monthly sampling for moisture)Check: Oil condition check beneath propeller for leaking seal indicators (monthly sampling for moisture)
- Area: Sacrificial anode (zinc) condition assessment and renewal (minimum annually)Check: Sacrificial anode (zinc) condition assessment and renewal (minimum annually)
- Area: Motor bearing and joint lubrication (monthly)Check: Motor bearing and joint lubrication (monthly)
- Area: Electrical connections and control system testing for corrosion and proper functionCheck: Electrical connections and control system testing for corrosion and proper function
- Area: Gear oil level verification (typically 90-weight) and condition monitoringCheck: Gear oil level verification (typically 90-weight) and condition monitoring
Typ-universelle Inspektionspunkte fuer Bow/Stern Thrusters (verifiziert, 2026-06).
Brunvoll
45
FU-80-LTC-2000
2000 kW
· 2000.0 kW
· Seawater
· CPP tunnel thruster
Common Failures & Inspection Points
- Hydraulic leakage or low oil level causes reduced pressure, slow movement or low-level alarms
- Pump, motor or drive faults cause loss of one power unit, reduced thrust or failure to move the rudder
- Control, feedback or position-sensor faults cause hunting, incorrect indication or failure to reach the commanded position
- Bearing, seal or mechanical wear causes vibration, leakage, backlash or abnormal noise
- Air ingress, contamination or cooling faults cause unstable hydraulic or drive performance and protective trips
Service: Inspect power units, oil or lubrication condition, actuators or thruster drive, seals, feedback transmitters, controls and structural connections. Test main, standby and emergency arrangements according to the approved vessel and class procedure. Check leakage, vibration and response throughout the operating range. Refer to the manufacturer documentation for the exact figure for pressure, alignment and wear limits.
Spare Parts: Carry hydraulic filters, seals, hose or pipe repair provisions, motor-control spares, feedback sensors, relays, fuses and critical valve or drive service parts.
Strengths
- Variable thrust without changing motor speed thanks to CPP hub
- Compact tunnel design fits in limited hull space
- Good low‑speed thrust efficiency for DP and port maneuvers
- Proven Brunvoll build quality with marine‑grade materials
Weaknesses
- Gear tooth wear reported in service, requiring regular inspection
- Shaft seal leakage can lead to maintenance downtime
- CPP hub oil leaks have been noted on this model
- Motor overheating if cooling system is not adequately maintained
Typical Vessels:
Offshore supply vesselAnchor handling tug supply (AHTS)Platform supply vessel (PSV)Workboat / crew transfer vessel
Decision Guide: Choose if you need a compact thruster with variable thrust for dynamic positioning or tight‑space port operations. Avoid if your maintenance regime cannot accommodate frequent gear and seal inspections, or if you prefer a fixed‑pitch unit with lower upkeep.
Use Cases: Steering and harbour manoeuvring on merchant, passenger, offshore and work vessels.
Tunnel Thruster FU
300-3500 kW
· 1500.0 kW
· Seawater
· Electric tunnel thruster
Power (kW)
1500
Type
Tunnel Thruster Electric
Common Failures & Inspection Points
- Hydraulic leakage or low oil level causes reduced pressure, slow movement or low-level alarms
- Pump, motor or drive faults cause loss of one power unit, reduced thrust or failure to move the rudder
- Control, feedback or position-sensor faults cause hunting, incorrect indication or failure to reach the commanded position
- Bearing, seal or mechanical wear causes vibration, leakage, backlash or abnormal noise
- Air ingress, contamination or cooling faults cause unstable hydraulic or drive performance and protective trips
Service: Inspect power units, oil or lubrication condition, actuators or thruster drive, seals, feedback transmitters, controls and structural connections. Test main, standby and emergency arrangements according to the approved vessel and class procedure. Check leakage, vibration and response throughout the operating range. Refer to the manufacturer documentation for the exact figure for pressure, alignment and wear limits.
Spare Parts: Carry hydraulic filters, seals, hose or pipe repair provisions, motor-control spares, feedback sensors, relays, fuses and critical valve or drive service parts.
Strengths
- 1500 kW rating gives strong side thrust for large offshore and ferry vessels
- Fixed‑pitch, direct‑drive design reduces hydraulic complexity and maintenance
- Motor‑reversal provides instant change of thrust direction without clutch wear
- Robust construction suited to harsh offshore environments (salt spray, vibration)
- Annual gear inspection program supported by Brunvoll simplifies upkeep
Weaknesses
- Large hull penetration required; installation is invasive and costly
- Higher capital cost compared with conventional hydraulic thrusters of similar power
- Fixed‑pitch propeller can suffer blade‑tip erosion in abrasive or sediment‑laden waters
- Main bearing wear and shaft seal leakage are known wear items that need periodic overhaul
- Thrust vector limited to transverse direction only; no 360° azimuth capability
Typical Vessels:
Offshore supply vesselFerryPlatform support vesselAnchor handling tug supply (AHTS)
Decision Guide: Choose if you need high side thrust for large offshore or ferry vessels, value a low‑maintenance electric drive and rapid reversal, and can accommodate the hull penetration. Avoid if budget constraints favour cheaper hydraulic units, the vessel requires azimuthal thrusting, or operating in highly abrasive water where blade erosion would be excessive.
Use Cases: Steering and harbour manoeuvring on merchant, passenger, offshore and work vessels.
Brunvoll FU-100 bow
unverified
· 100.0 kW
· electric tunnel thruster
Power (kW)
100
Thrust (kN)
13.0
Diameter (mm)
470
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑size ratio – 13 kN in a relatively small 470 mm tunnel
- Direct‑drive electric motor gives high efficiency and low noise
- Modular, quick‑install design reduces docktime for retrofits
- Integrated control electronics compatible with most DP and helm systems
- Proven reliability on a range of mid‑size vessels
Weaknesses
- Maximum thrust may be insufficient for large tankers or high‑speed DP vessels
- Requires dedicated 100 kW electrical supply and cooling capacity
- Tunnel diameter limits installation in very narrow hull sections
- Potential cavitation at high RPM if not properly matched to hull geometry
- Initial purchase price higher than basic hydraulic units
Typical Vessels:
Handymax Bulk CarrierMedium‑size Tanker (up to ~30,000 dwt)Offshore Supply VesselFerryContainer Feeder
Decision Guide: Choose if you need a compact, high‑efficiency bow thruster delivering around 13 kN for vessels up to ~30 kt and have sufficient electrical power. Avoid if the vessel requires >20 kN thrust, has very limited hull space for a 470 mm tunnel, or operates on a purely hydraulic power system.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
Brunvoll FU-100 stern
unverified
· 100.0 kW
· ducted tunnel thruster
Power (kW)
100
Thrust (kN)
13.0
Diameter (mm)
470
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (≈13 kN at 100 kW)
- Compact footprint suitable for stern locations with limited space
- Low vibration and noise due to enclosed duct design
- Integrated control electronics compatible with standard ship automation systems
- Proven reliability in harsh North Sea operating conditions
Weaknesses
- Fixed tunnel geometry limits efficiency at off‑design speeds compared with azimuth units
- Requires hull penetration and internal space, affecting structural layout
- 100 kW power may be insufficient for larger vessels needing higher maneuvering thrust
- Maintenance access can be difficult in stern installations
- Higher upfront cost than basic open‑propeller thrusters
Typical Vessels:
Handymax bulk carrierProduct tankerOffshore supply vesselCruise ship (mid‑size)Container feeder
Decision Guide: Choose if you need a reliable, low‑noise stern thruster for vessels up to ~30 000 dwt with limited power budget and space constraints. Avoid if the vessel requires higher thrust (>15 kN), full 360° azimuth capability, or a lower‑cost open‑propeller solution.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
Brunvoll FU-150 bow
unverified
· 150.0 kW
· tunnel thruster
Power (kW)
150
Thrust (kN)
19.5
Diameter (mm)
505
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (≈0.13 kN/kW) for its size
- Compact tunnel geometry fits tight hull spaces
- Water‑lubricated bearings give low vibration and maintenance intervals
- Integrated control electronics compatible with most ship bridge systems
- Proven reliability from extensive service on European coastal vessels
Weaknesses
- Cavitation can appear at high RPM or in shallow water
- Tunnel lining requires periodic inspection for wear or fouling
- Limited thrust compared with larger azimuth pods for very large ships
- Installation demands structural reinforcement of the hull bow section
- Power consumption relatively high for modest maneuvering tasks
Typical Vessels:
Handymax bulk carrierProduct tanker (≤30,000 DWT)Offshore supply vesselCruise ship feederContainer feeder
Certifications:
IMO Type ApprovalDNV GL Classification
Decision Guide: Choose if you need a reliable moderate‑power bow thruster for vessels up to ~30 000 DWT, have limited hull space and prefer a proven tunnel design with low maintenance. Avoid if the vessel requires very high thrust (>25 kN), azimuth steering capability, or ultra‑quiet operation in noise‑sensitive environments.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
Brunvoll FU-150 stern
unverified
· 150.0 kW
· tunnel thruster
Power (kW)
150
Thrust (kN)
19.5
Diameter (mm)
505
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (≈19.5 kN at 150 kW) for its size
- Compact tunnel design fits into existing hull sections without major structural changes
- Proven reliability of Brunvoll’s propeller‑duct system with good cavitation resistance
- Low acoustic signature, beneficial for offshore and passenger vessels
Weaknesses
- Fixed‑direction thrust; cannot rotate like an azimuth pod
- Maintenance requires periodic inspection of the propeller and duct bearings
- Performance drops noticeably in very shallow water due to reduced inflow
- Installation may be limited by hull thickness or internal space constraints
Typical Vessels:
Platform Supply Vessel (PSV)Offshore Support VesselSmall Crude Oil TankerContainer FeederCruise Ship (stern maneuvering aid)
Certifications:
DNV
Decision Guide: Choose if you need a reliable, compact stern thruster delivering ~20 kN thrust for DP or port manoeuvring on vessels up to medium size and have sufficient hull space for a tunnel installation. Avoid if you require omnidirectional thrust, higher thrust levels, or have very shallow draft constraints that limit tunnel flow.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Brunvoll FU-200 bow
unverified
· 200.0 kW
· electric tunnel thruster
Power (kW)
200
Thrust (kN)
26.0
Diameter (mm)
540
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (≈0.13 kN/kW) for its size class
- Compact 540 mm duct fits vessels with limited hull space
- Proven Brunvoll reliability and low maintenance design
- Optional variable‑frequency drive enables fine thrust control
- Robust corrosion‑resistant housing suitable for marine environments
Weaknesses
- Tunnel geometry can cause hull vibration in heavy seas
- Requires regular duct cleaning to maintain performance
- Fixed installation limits retrofitting on already‑built ships
- Power demand (200 kW) may be high for vessels with limited electrical generation capacity
- Less effective than azimuth thrusters for high‑speed DP operations
Typical Vessels:
Handymax bulk carrierProduct tanker (up to ~30 kt)Feeder container shipOffshore supply / platform support vessel
Decision Guide: Choose the FU‑200 when a vessel needs strong bow thrust in a confined hull space, has sufficient electrical power, and values Brunvoll’s track record for durability. Avoid it on ships that already employ azimuth or pod thrusters, on very small vessels with limited power generation, or where hull reinforcement for a tunnel duct is impractical.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Brunvoll FU-200 stern
unverified
· 200.0 kW
· tunnel thruster
Power (kW)
200
Thrust (kN)
26.0
Diameter (mm)
540
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (26 kN at 200 kW) for its size
- Compact tunnel diameter (540 mm) fits limited hull space
- Proven reliability of Brunvoll’s marine‑grade bearings and sealed motor design
- Low acoustic signature, suitable for noise‑sensitive operations
- Standardized ABS/DNV class approvals simplify certification
Weaknesses
- Fixed‑direction thrust; cannot rotate like a pod or azimuth thruster
- Requires significant hull penetration and internal space for the tunnel duct
- Cavitation risk at full load in shallow water may reduce efficiency
- Maintenance access can be limited on existing vessels without redesign
Typical Vessels:
Handymax bulk carrierProduct tanker (up to ~30 k DWT)Feeder container shipOffshore supply vesselCruise ship auxiliary maneuvering system
Certifications:
ABSDNV GL
Decision Guide: Choose if you need a medium‑size, high‑thrust stern thruster for vessels with limited hull space and require proven class approvals. Avoid if you demand azimuthing thrust, higher than 30 kN thrust, or have severe weight/space constraints that favour smaller units.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Brunvoll FU-300 bow
unverified
· 300.0 kW
· tunnel bow thruster
Power (kW)
300
Thrust (kN)
39.0
Diameter (mm)
610
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (≈13 kN per 100 kW) for its size
- Compact tunnel diameter (610 mm) fits vessels with limited hull space
- Robust, low‑maintenance construction typical of Brunvoll designs
- Integrated control interface compatible with most ship bridge systems
- Proven performance in DP‑assisted maneuvering for vessels up to ~30 000 dwt
Weaknesses
- Maximum thrust (39 kN) may be insufficient for large tankers or cruise ships requiring >50 kN
- Requires a dedicated 300 kW power supply and associated cabling/hydraulic infrastructure
- Tunnel geometry can be more prone to fouling than ducted‑propeller designs, affecting efficiency over time
- Weight and installation space not disclosed; may impact vessel weight budget
Typical Vessels:
Product tanker (up to ~30 000 dwt)Container feederHandymax bulk carrierOffshore supply vesselCruise ship (mid‑size) for auxiliary maneuvering
Decision Guide: Choose if: you need a reliable, compact bow thruster delivering ~40 kN thrust for vessels up to ~30 000 dwt, and you have the required 300 kW power supply. Avoid if: higher thrust (>50 kN) is essential, hull space cannot accommodate a 610 mm tunnel, or you prefer azimuth‑type thrusters for extreme maneuverability.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Brunvoll FU-300 stern
unverified
· 300.0 kW
· tunnel thruster
Power (kW)
300
Thrust (kN)
39.0
Diameter (mm)
610
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (39 kN at 300 kW) for effective docking and DP assistance
- Relatively small tunnel diameter (610 mm) fits vessels with limited hull space
- Robust, corrosion‑resistant construction typical of Brunvoll’s Norwegian engineering standards
- Straightforward installation in a stern tunnel with proven mounting kits
- Low acoustic signature compared with some azimuth pod solutions
Weaknesses
- 300 kW motor power results in higher fuel consumption than lower‑power alternatives
- Requires hull penetration and structural reinforcement, increasing dry‑dock time and cost
- Fixed‑direction design limits flexibility; not suitable where 360° thrust is required
- Potential for cavitation at very high propeller speeds if not matched to vessel speed profile
- Higher upfront cost than basic low‑thrust tunnel units
Typical Vessels:
Aframax tankerVLCC/ULCC tanker (stern‑only thruster)Container ship (>8,000 TEU)Cruise shipOffshore supply vessel with DP2 requirements
Decision Guide: Choose if: you need a high‑thrust stern thruster for a large vessel with limited hull space and require reliable low‑speed maneuverability or DP support. Avoid if: the vessel is small, budget‑constrained, or requires omnidirectional thrust (azimuth pod) rather than a fixed‑direction unit.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Brunvoll FU-400 bow
unverified
· 400.0 kW
· ducted tunnel thruster
Power (kW)
400
Thrust (kN)
52.0
Diameter (mm)
680
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (52 kN at 400 kW) gives strong manoeuvring capability.
- Compact 680 mm duct diameter fits vessels with limited hull space.
- Brunvoll’s proven reliability and low vibration/noise levels suit passenger and offshore vessels.
- Integrated control electronics simplify installation and DP integration.
Weaknesses
- Maximum thrust may be insufficient for very large tankers or high‑speed DP‑3 ships.
- Hull penetration required; installation can be complex on existing vessels.
- Impeller maintenance generally requires dry‑docking, adding lifecycle cost.
- Performance can degrade in shallow water due to increased suction effects.
Typical Vessels:
Product TankerBulk Carrier (up to ~30 kt)Offshore Supply VesselCruise FerryContainer Ship (mid‑size)
Decision Guide: Choose if you need strong bow thrust in a limited hull space, require low noise for passenger comfort, or plan DP‑2 operations on medium‑size vessels. Avoid if vessel size exceeds the 400 kW power envelope, budget constraints limit upfront cost, or operating primarily in very shallow ports where suction may be problematic.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Brunvoll FU-400 stern
unverified
· 400.0 kW
· hydraulic tunnel thruster
Power (kW)
400
Thrust (kN)
52.0
Diameter (mm)
680
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (52 kN at 400 kW) for effective bow‑/stern‑sideways control
- Robust, corrosion‑resistant steel housing suitable for harsh marine environments
- Integrated control system compatible with most ship bridge consoles
- Compact tunnel diameter (680 mm) minimises hull penetration and internal space loss
- Class‑approved design reduces certification effort for new builds
Weaknesses
- Relatively high power demand increases auxiliary engine load
- Installation requires precise alignment of the tunnel duct, adding dockyard time
- Hydraulic system adds complexity and maintenance compared with electric thrusters
- Noise and vibration can be noticeable in passenger‑focused vessels if not properly isolated
- Spare parts may have longer lead times for remote operators
Typical Vessels:
Aframax tankerPanamax container shipHandymax bulk carrierCruise shipOffshore supply vessel
Certifications:
DNV GL class approvalABS class approvalLR (Lloyd's Register) class approval
Decision Guide: Choose if: you need strong low‑speed manoeuvring on a large vessel, have sufficient hull space for a 680 mm tunnel, and prefer a proven, class‑approved hydraulic system. Avoid if: the ship has strict noise limits, limited auxiliary power, or you favour an all‑electric solution with lower maintenance.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
Brunvoll FU-500 bow
unverified
· 500.0 kW
· tunnel thruster
Power (kW)
500
Thrust (kN)
65.0
Diameter (mm)
750
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (65 kN at 500 kW) for effective bow assistance
- Compact tunnel diameter (750 mm) fits within standard hull sections
- Robust, low‑maintenance design with proven Brunvoll reliability
- Low acoustic signature – suitable for noise‑sensitive vessels
- Straightforward integration into existing hull structures
Weaknesses
- Requires a sizable hull opening; may limit internal layout options
- Fixed azimuth – cannot rotate like an azipod, limiting directional flexibility
- Power demand can be high for vessels with limited generator capacity
- Maintenance access is through the tunnel, which can be time‑consuming
- Not optimal for ultra‑large ships where higher thrust levels are required
Typical Vessels:
Offshore supply vesselCruise ship (up to ~150 m length)Container feederGeneral cargo / bulk carrier (mid‑size)LNG/LPG carrier (small to medium)
Decision Guide: Choose if: you need a reliable, high‑thrust bow thruster for vessels up to ~150 m that operate frequently in tight ports or require dynamic positioning support. Avoid if: hull space is severely limited, the vessel requires full 360° thrust coverage, or power generation capacity cannot accommodate a 500 kW unit.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Brunvoll FU-500 stern
unverified
· 500.0 kW
· tunnel thruster
Power (kW)
500
Thrust (kN)
65.0
Diameter (mm)
750
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (65 kN) relative to power consumption (500 kW)
- Compact 750 mm tunnel diameter fits in medium‑size hull openings
- Robust stainless‑steel construction suitable for harsh marine environments
- Integrated control electronics compatible with most ship bridge systems
- Low acoustic signature compared with conventional propeller‑type thrusters
Weaknesses
- Requires significant hull reinforcement at the stern installation point
- High electrical power demand may limit use on vessels with restricted generator capacity
- Maintenance of large bearing assemblies can be labour‑intensive
- Installation space needed for duct and motor may conflict with aft cargo or equipment layouts
- Limited thrust modulation below rated power compared with variable‑pitch azimuth thrusters
Typical Vessels:
Container shipCrude oil tankerLNG carrierOffshore supply vesselCruise ship
Decision Guide: Choose if: you need a reliable, high‑thrust stern thruster for vessels >30 000 gt with sufficient electrical generation capacity and space for a 750 mm tunnel. Avoid if: the vessel has tight aft space constraints, low power availability, or requires fine thrust modulation beyond what a fixed‑pitch tunnel can deliver.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
Brunvoll FU-600 bow
unverified
· 600.0 kW
· fixed tunnel thruster
Power (kW)
600
Thrust (kN)
78.0
Diameter (mm)
820
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (78 kN @ 600 kW) for strong docking assistance
- Compact 820 mm duct size fits into limited bow spaces
- Robust stainless‑steel housing and proven Brunvoll reliability
- Low vibration and noise levels compared with open‑propeller designs
- Straightforward installation and maintenance access
Weaknesses
- Fixed tunnel cannot be retracted, adding hull resistance when under way
- Requires significant bow structural reinforcement and sealing
- Power demand (600 kW) may be high for vessels with limited electrical capacity
- Diameter limits use to vessels that can accommodate an 820 mm opening
Typical Vessels:
Container ships (up to ~30,000 dwt)Product tankersHandymax bulk carriersOffshore supply / support vesselsCruise ships and ferries of similar size
Certifications:
DNV class approval
Decision Guide: Choose if you need strong, reliable bow thrust on a medium‑size vessel with limited bow space and can accommodate a fixed tunnel. Avoid if the ship requires a retractable thruster to minimise resistance at cruise speed or has strict weight/electrical power limits.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Brunvoll FU-600 stern
unverified
· 600.0 kW
· ducted tunnel thruster
Power (kW)
600
Thrust (kN)
78.0
Diameter (mm)
820
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (≈78 kN at 600 kW)
- Compact tunnel layout fits in limited hull space
- Low vibration and noise due to optimized duct geometry
- Proven reliability with long service history on tankers and cruise ships
- Available with integrated control unit for precise thrust command
Weaknesses
- Fixed‑direction thrust; cannot provide 360° vectoring like azimuth pods
- Duct and propeller require periodic inspection and dry‑docking maintenance
- Higher fuel consumption than electric podded thrusters when used continuously
- Installation limited to stern positions with sufficient hull opening
- Noise can increase noticeably at full power in confined spaces
Typical Vessels:
Crude oil tankerProduct tankerCruise shipOffshore supply vesselLarge container ship (>10 000 GT)
Certifications:
DNVGL Type Approval
Decision Guide: Choose if you need a high‑thrust, space‑efficient thruster for low‑speed maneuvering or as a DP backup on large vessels with stern tunnel provisions. Avoid if the vessel requires full azimuth thrust capability, continuous high‑power operation, or wants to minimise hull penetrations.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Brunvoll FU-750 bow
unverified
· 750.0 kW
· tunnel thruster
Power (kW)
750
Thrust (kN)
97.5
Diameter (mm)
925
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (≈130 N/kW) for strong bow assistance
- Compact tunnel size (925 mm) fits medium‑size hull openings
- Brunvoll’s proven reliability and long service life in harsh marine environments
- Integrated cooling and sealed bearing system reduces maintenance intervals
- Low vibration and noise compared with open‑propeller azimuth units
Weaknesses
- Tunnel geometry limits effectiveness at higher vessel speeds or heavy seas
- Potential for cavitation if operated near design RPM limits
- Requires hull penetration and structural reinforcement, adding installation complexity
- Higher electrical power demand than comparable azimuth thrusters for the same maneuverability envelope
- Control system must be integrated with ship’s bridge console; not a plug‑and‑play solution
Typical Vessels:
Container ships (up to ~10 000 gt)General cargo and Ro‑Ro vesselsOffshore support / supply vesselsCruise ships (mid‑size)Bulk carriers and tankers where a bow thruster is required for port entry
Decision Guide: Choose if the vessel needs strong, reliable bow thrust for tight‑port manoeuvring, has sufficient hull space for a ~1 m tunnel, and prefers lower maintenance over full‑azimuth capability. Avoid if 360° thrust vectoring is required, hull thickness limits tunnel installation, or power availability is constrained.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Brunvoll FU-750 stern
unverified
· 750.0 kW
· tunnel thruster
Power (kW)
750
Thrust (kN)
97.5
Diameter (mm)
925
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (≈97.5 kN) for its power rating, enabling rapid low‑speed manoeuvring
- Large 925 mm tunnel diameter reduces cavitation and improves efficiency
- Robust marine‑grade construction suited to harsh offshore environments
- Integrated control electronics compatible with most ship bridge systems
- Proven track record on a range of large commercial vessels
Weaknesses
- Large physical size limits installation on smaller hulls or retrofits with space constraints
- High power demand (750 kW) increases fuel consumption and electrical load
- Maintenance of bearings, seals and the tunnel liner can be intensive
- Noise and vibration levels are higher than some azimuth‑type thrusters
- Capital cost is relatively high compared to lower‑power alternatives
Typical Vessels:
VLCC / Suezmax TankerContainer Ship (≥30,000 gt)Cruise ShipOffshore Supply VesselLNG Carrier
Certifications:
DNV
Decision Guide: Choose if the vessel exceeds ~30,000 gt and requires a powerful stern thruster for port entry/exit, dynamic positioning or emergency stopping. Avoid on small to medium vessels where space, weight or budget constraints make lower‑power or azimuth thrusters more appropriate.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
Brunvoll FU-1000 bow
unverified
· 1000.0 kW
· electric tunnel thruster
Power (kW)
1000
Thrust (kN)
130.0
Diameter (mm)
1100
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (≈130 kN at 1000 kW) suitable for large vessels
- Compact 1100 mm duct diameter reduces hull penetration size
- Robust steel housing and water‑cooled motor give long service life with low maintenance
- Integrated variable frequency drive enables fine thrust control and energy efficiency
- Proven design widely used in commercial shipping, offering good cavitation performance
Weaknesses
- Significant power demand; requires dedicated electrical supply and cooling infrastructure
- Hull opening for the duct can be complex to retrofit on existing ships
- Higher upfront cost compared with basic low‑power thrusters
- Noise and vibration at full load may require additional acoustic mitigation measures
- Limited effectiveness in very high‑speed manoeuvring where azimuth or pod systems are preferred
Typical Vessels:
Container ships (≥8 000 gt)Crude oil and product tankersLNG carriersCruise linersOffshore supply vesselsRo‑Ro ferries
Decision Guide: Choose if the vessel needs strong bow thrust for docking, dynamic positioning or emergency manoeuvring and has sufficient electrical capacity and hull space for a 1 m duct. Avoid if the ship is small, budget‑constrained, or would benefit more from an azimuth thruster that provides 360° thrust without a fixed tunnel.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
Brunvoll FU-1000 stern
unverified
· 1000.0 kW
· high‑power tunnel thruster
Power (kW)
1000
Thrust (kN)
130.0
Diameter (mm)
1100
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (≈130 kN) relative to power consumption (1 000 kW)
- Compact 1.1 m tunnel diameter fits in limited stern space on large ships
- Class‑approved design with robust steel housing and corrosion‑resistant components
- Integrated control electronics compatible with most ship automation systems
- Low acoustic signature compared with external propeller thrusters
Weaknesses
- Requires significant hull penetration and structural reinforcement during installation
- High electrical power demand may strain vessel generators on smaller ships
- Maintenance of bearings, seals and the tunnel liner can be labour‑intensive
- Limited effectiveness if stern draft is shallow or space constraints prevent full tunnel length
- Not suitable for vessels that prefer azimuth pod or water‑jet maneuvering solutions
Typical Vessels:
Crude oil tankerProduct tankerContainer ship (≥8 000 TEU)Cruise linerOffshore supply vesselLNG carrier
Certifications:
DNV GL class approvalIMO D‑2 design standard
Decision Guide: Choose if: you need high thrust for precise docking or DP assistance on a large vessel, have sufficient stern space for a 1.1 m tunnel, and require a class‑approved thruster with proven reliability. Avoid if: the ship is small or power‑limited, hull geometry cannot accommodate the tunnel length, or an azimuth pod or water‑jet system better fits operational requirements.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
Brunvoll FU-1200 bow
unverified
· 1200.0 kW
· tunnel thruster
Power (kW)
1200
Thrust (kN)
156.0
Diameter (mm)
1240
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust‑to‑power ratio (156 kN at 1 200 kW) suitable for mega‑vessels
- Compact tunnel layout minimizes deck space and preserves hull integrity
- Robust stainless‑steel construction with proven resistance to corrosion and cavitation
- Integrated control electronics compatible with most ship automation systems
- Low acoustic signature, beneficial for passenger comfort on cruise ships
Weaknesses
- Large tunnel diameter (≈1.24 m) may limit installation in narrow hull sections
- Requires significant hull reinforcement and precise alignment during fit‑out
- Higher initial procurement and installation cost compared with smaller thrusters
- Power consumption is substantial; not ideal for vessels with limited generator capacity
- Efficiency drops at very low propeller speeds, reducing effectiveness in some DP modes
Typical Vessels:
Cruise shipLNG carrierLarge container vesselBulk carrier (>30 kt)Offshore supply / DP vessel
Decision Guide: Choose if the vessel needs high bow thrust for safe port entry, dynamic positioning or tight‑berth maneuvering on ships larger than 150 m LOA. Avoid if hull geometry cannot accommodate a 1.24 m tunnel, budget constraints dominate, or the ship’s power plant cannot support an additional 1.2 MW load.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
Brunvoll FU-1200 stern
unverified
· 1200.0 kW
· tunnel thruster
Power (kW)
1200
Thrust (kN)
156.0
Diameter (mm)
1240
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (156 kN at 1200 kW) gives excellent maneuvering force
- Robust stainless‑steel duct and propeller reduces cavitation and wear
- Integrated control system compatible with DP and conventional helm stations
- Proven reliability on long‑range tankers and cruise ships
- Modular design allows both electric and hydraulic drive options
Weaknesses
- Large 1240 mm duct diameter limits installation in vessels with narrow hull sections
- High power demand requires substantial onboard electrical or hydraulic capacity
- Initial capital cost is higher than smaller‑size thrusters from low‑cost manufacturers
- Noise and vibration levels can be significant if not properly isolated
- Maintenance access may require removal of surrounding plating on some ship designs
Typical Vessels:
Crude oil tankerProduct tankerContainer ship (≥8 000 TEU)Cruise linerOffshore supply vessel
Certifications:
DNV
Decision Guide: Choose if the vessel needs strong low‑speed thrust for safe docking, dynamic positioning or maneuvering in confined ports and has sufficient hull space and power supply. Avoid if installation space is limited, budget constraints dominate, or a lower‑power thruster would meet the operational profile.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
Brunvoll FU-1500 bow
unverified
· 1500.0 kW
· Tunnel thruster
Power (kW)
1500
Thrust (kN)
195.0
Diameter (mm)
1450
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust‑to‑power ratio (195 kN at 1500 kW) enables rapid lateral movement.
- Large 1.45 m duct diameter improves hydraulic efficiency and reduces cavitation risk.
- Brunvoll’s proven reliability and long service life in harsh marine environments.
- Integrated control electronics compatible with most ship‑automation systems.
- Suitable for dynamic positioning and tight‑harbor maneuvers on mega‑vessels.
Weaknesses
- Physical size limits installation to vessels with sufficient bow space.
- High power demand increases fuel consumption of auxiliary generators.
- Initial capital cost is higher than lower‑rated thrusters.
- Maintenance access can be more complex due to the large duct and motor arrangement.
- Potential for increased noise and vibration if not properly isolated.
Typical Vessels:
Very Large Crude Carriers (VLCC)Ultra‑Large Container ShipsCapesize Bulk CarriersOffshore Supply Vessels with DPCruise ships over 150 m LOA
Decision Guide: Choose if: you need a bow thruster that can generate >190 kN for vessels >80,000 DWT, require reliable performance in DP or confined ports, and have sufficient hull space. Avoid if: vessel size or budget cannot accommodate the large duct and high power rating, or if lower thrust levels are acceptable.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Brunvoll FU-1500 stern
unverified
· 1500.0 kW
· tunnel thruster
Power (kW)
1500
Thrust (kN)
195.0
Diameter (mm)
1450
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (≈195 kN at 1500 kW) suitable for very large ships
- Robust stainless‑steel housing and impeller design for long service life
- Modular construction allows relatively easy on‑site maintenance and part replacement
- Integrated control electronics compatible with most ship bridge systems
- Proven track record in tanker and container vessel applications
Weaknesses
- Large tunnel diameter (1.45 m) limits installation to vessels with sufficient hull space
- High power demand increases fuel consumption of the auxiliary system
- Weight and structural reinforcement requirements can add to overall ship weight
- Requires dedicated cooling and ventilation systems in the engine room
- May be over‑spec for vessels under 30,000 DWT where a smaller thruster would suffice
Typical Vessels:
Crude oil tankerProduct tankerContainer shipBulk carrierLNG/LPG carrier
Certifications:
DNV
Decision Guide: Choose if you need high‑power stern assistance for vessels >30,000 DWT with adequate hull space for a 1.45 m tunnel and require proven reliability in harsh conditions. Avoid if the vessel is smaller, has limited hull volume, or if an electric azimuth thruster offers better integration with existing DP systems.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
Brunvoll FU-2000 bow
unverified
· 2000.0 kW
· high-power tunnel thruster
Power (kW)
2000
Thrust (kN)
260.0
Diameter (mm)
1800
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (≈260 kN) suitable for mega‑size tankers and container ships
- Compact tunnel layout minimizes deck space while providing strong lateral force
- Integrated cooling and control system reduces downtime and simplifies operation
- Proven reliability with Brunvoll’s long track record in harsh marine environments
- Compatible with dynamic positioning (DP) systems for enhanced station‑keeping
Weaknesses
- High electrical power demand (≈2 MW) increases vessel energy budget
- Installation requires large hull penetration and structural reinforcement
- Maintenance of the tunnel interior can be labour‑intensive
- Potential cavitation at maximum thrust in shallow water conditions
- Higher upfront cost compared with lower‑power thruster alternatives
Typical Vessels:
VLCCULCVLNG carrierLarge cruise shipOffshore support vessel
Certifications:
DNV
Decision Guide: Choose if the vessel requires very high lateral thrust for safe docking, DP assistance or ice‑class operations and has sufficient power generation capacity. Avoid on smaller ships where the cost, power demand and installation complexity outweigh the maneuvering benefit.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Brunvoll FU-2000 stern
unverified
· 2000.0 kW
Power (kW)
2000
Thrust (kN)
260.0
Diameter (mm)
1800
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (260 kN) from a relatively compact 1.8 m duct, suitable for large ships with limited hull space
- Electric drive provides low acoustic signature and reduced emissions compared with diesel‑driven units
- Integrated control system compatible with most DP packages for seamless maneuvering
- Robust construction designed for harsh marine environments, offering long service intervals
Weaknesses
- Requires a high‑capacity electrical supply (typically several megawatts), which may necessitate upgrades to ship power distribution
- Higher upfront capital cost than smaller or lower‑power thrusters
- Installation can be complex due to the large duct diameter and need for precise alignment in the stern hull
- Maintenance of large bearings and seals demands specialized shore support
Typical Vessels:
Container shipsCrude oil tankersLNG carriersCruise linersOffshore supply vessels
Certifications:
DNV
Decision Guide: Choose if: you need maximum thrust for a large vessel with limited stern space and have sufficient electrical power capacity; the ship operates in ports where precise low‑speed control or DP is required. Avoid if: the vessel’s power plant cannot support the high electric demand, budget constraints are tight, or a smaller thruster would meet maneuvering needs.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
Brunvoll FU-2500 bow
unverified
· 2500.0 kW
· tunnel thruster
Power (kW)
2500
Thrust (kN)
325.0
Diameter (mm)
2150
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (≈325 kN) for its power rating, improving port handling and DP performance
- Robust, corrosion‑resistant stainless steel tunnel housing suitable for harsh marine environments
- Integrated water‑cooling system reduces overheating risk during prolonged use
- Proven track record on cruise ships, LNG carriers and large tankers – high reliability
- Relatively low acoustic signature compared with azimuth pods of similar power
Weaknesses
- Large tunnel diameter (≈2.15 m) consumes significant hull space and may limit installation options
- High electrical demand (≈2.5 MW) requires substantial onboard power generation capacity
- Fixed‑pitch propeller limits fine thrust control; variable‑pitch versions are not standard
- Installation involves hull penetration, increasing dry‑dock time and potential for leaks if not fitted correctly
- Efficiency drops sharply at higher vessel speeds – thruster is intended for low‑speed maneuvering only
Typical Vessels:
Cruise shipsLNG carriersLarge tankers (VLCC, LR2)Container vessels >150 m LOAOffshore supply vessels / FPSOs
Certifications:
DNV GL Class NotationABS ClassificationIMO Type Approval for tunnel thrusters
Decision Guide: Choose if the vessel needs very high bow thrust for tight port manoeuvring, dynamic positioning or emergency stopping and has sufficient hull volume and power generation capacity. Avoid if hull space is limited, the ship operates primarily at higher speeds where a more efficient azimuth pod would be preferable, or the onboard electrical plant cannot support ~2.5 MW continuous load.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
Brunvoll FU-2500 stern
unverified
· 2500.0 kW
· electric tunnel thruster
Power (kW)
2500
Thrust (kN)
325.0
Diameter (mm)
2150
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (325 kN) in a relatively compact 2150 mm diameter housing
- Integrated variable‑pitch propeller gives good efficiency across a range of speeds
- Water‑cooled electric motor reduces vibration and noise, enhancing crew comfort
- Robust design with proven service record on cruise ships and LNG carriers
- Compact installation footprint compared with comparable azimuth units
Weaknesses
- Large hull penetration and overall weight increase structural complexity
- High electrical power demand requires substantial shipboard power distribution upgrades
- Higher capital cost than lower‑power tunnel thrusters or basic bow thrusters
- Limited 360° thrust capability; not as versatile for dynamic positioning as azimuth pods
- Maintenance access can be difficult due to stern location and confined tunnel space
Typical Vessels:
Cruise ShipLNG CarrierContainer VesselBulk CarrierOffshore Support Vessel
Certifications:
DNV
Decision Guide: Choose if the vessel needs high thrust for precise docking or station‑keeping, has sufficient electrical power capacity, and values a proven, low‑noise solution. Avoid if budget is tight, the ship is small to medium size, or a 360° thrust capability (azimuth thruster) is required for dynamic positioning.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
Brunvoll FU-3000 bow
unverified
· 3000.0 kW
· ducted tunnel thruster
Power (kW)
3000
Thrust (kN)
390.0
Diameter (mm)
2500
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust‑to‑power ratio (≈0.13 kN/kW) for rapid lateral movement
- Robust stainless‑steel duct and propeller construction suited to harsh sea conditions
- Integrated control electronics compatible with most DP and ship‑handling systems
- Low acoustic signature compared with external azimuth thrusters, beneficial for passenger comfort
- Proven track record on ultra‑large crude carriers (ULCC) and cruise ships
Weaknesses
- Large tunnel diameter (2.5 m) requires significant hull penetration and structural reinforcement
- Higher initial purchase and installation cost than smaller bow thrusters
- Maintenance access can be limited; periodic inspection of the duct interior is required
- Weight and space requirements limit suitability for vessels under 30 000 gt or with narrow hull forms
- Power demand (3 MW) may exceed the capacity of older ship electrical systems
Typical Vessels:
Ultra‑large crude carriers (ULCC)Very large crude carriers (VLCC)Large container ships (>10 000 gt)Cruise linersOffshore supply vessels with DP capability
Decision Guide: Choose if: the vessel exceeds 30 000 gt, operates in confined ports or requires high‑precision DP manoeuvring and can accommodate a 2.5 m tunnel. Avoid if: hull space is limited, power plant cannot supply ~3 MW for thruster operation, or the maneuverability requirements are modest.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Brunvoll FU-3000 stern
unverified
· 3000.0 kW
· high‑power tunnel thruster
Power (kW)
3000
Thrust (kN)
390.0
Diameter (mm)
2500
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust output (≈390 kN) for its size, enabling rapid maneuvering even on large vessels
- Compact duct design reduces hull penetration and structural reinforcement needs compared with larger azimuth pods
- Robust stainless‑steel construction rated for harsh offshore environments and extended service intervals
- Integrated control electronics compatible with most ship bridge systems for precise thrust vectoring
- Low cavitation design improves efficiency and reduces noise/vibration
Weaknesses
- High power demand (3 MW) increases fuel consumption when used frequently
- Installation requires significant hull modifications and reinforcement of the stern section
- Limited access space can make routine maintenance more time‑consuming
- Large duct diameter may restrict placement on vessels with tight aft arrangements
- Noise and vibration levels, while mitigated, are still higher than some low‑speed azimuth thrusters
Typical Vessels:
Cruise shipLNG carrierOffshore supply vessel (OSV)Heavy lift / project cargo vesselLarge container or bulk carrier with enhanced maneuverability requirements
Decision Guide: Choose if: you need very high lateral thrust for a large vessel, have sufficient aft space for a 2.5 m duct, and require proven reliability in harsh offshore conditions. Avoid if: power budget is limited, hull geometry cannot accommodate the large tunnel, or low‑noise operation is a primary requirement.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Brunvoll FU-3500 bow
unverified
· 3500.0 kW
· Tunnel thruster
Power (kW)
3500
Thrust (kN)
455.0
Diameter (mm)
2850
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust‑to‑power ratio (455 kN at 3500 kW) for rapid docking and undocking
- Compact tunnel layout fits within hull structure without protruding deck equipment
- Robust steel construction with proven reliability in harsh marine environments
- Low acoustic signature, beneficial for passenger vessels and offshore platforms
- Class‑approved with integrated control electronics compatible with DP systems
Weaknesses
- Large tunnel diameter (2.85 m) limits installation to vessels with sufficient hull space
- High power demand increases fuel consumption of auxiliary generators
- Maintenance of bearings, seals and the tunnel lining can be intensive on long‑term operation
- Installation requires precise alignment; retrofits on existing ships may be costly
- Efficiency drops at very low propeller speeds, limiting effectiveness in some slow‑speed maneuvers
Typical Vessels:
Very Large Crude Carriers (VLCC)Ultra‑Large Container Ships (ULCS)Cruise shipsOffshore supply vessels (OSV) with DPLNG carriers
Certifications:
DNV GL class approvalABS class approval
Decision Guide: Choose if: you need a high‑thrust bow thruster for a large vessel, have sufficient hull space for a 2.85 m tunnel, and require class‑approved equipment with low noise for DP or port operations. Avoid if: the ship’s beam or hull geometry cannot accommodate the tunnel size, power generation capacity is limited, or you are fitting a small to medium vessel where a smaller thruster would be more economical.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Brunvoll FU-3500 stern
unverified
· 3500.0 kW
· hydraulic tunnel thruster
Power (kW)
3500
Thrust (kN)
455.0
Diameter (mm)
2850
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (≈455 kN) suitable for large tankers and offshore vessels
- Large duct diameter provides efficient water flow and reduced cavitation
- Robust hydraulic drive with water‑lubricated bearings for long service life
- Integrated control system compatible with DP and ship‑handling consoles
- Proven design from Brunvoll, a specialist in marine thrusters
Weaknesses
- High power demand (≈3.5 MW) increases fuel consumption and auxiliary load
- Large hull penetration required; installation is complex and costly
- Physical size limits use on vessels with restricted aft space
- Potential for higher acoustic signature compared with smaller electric thrusters
- Maintenance of hydraulic system adds to life‑cycle cost
Typical Vessels:
Very Large Crude Carriers (VLCC)LNG carriersCruise shipsOffshore supply vessels (OSV)Large container ships requiring DP assistance
Decision Guide: Choose if: you need maximum aft thrust for a vessel >150 m LOA, operate in restricted ports or require dynamic positioning. Avoid if: the ship is small to medium size, power budget is limited, or hull space at the stern cannot accommodate a 2.85 m tunnel.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Brunvoll FU-4000 bow
unverified
· 4000.0 kW
· High-power tunnel thruster
Power (kW)
4000
Thrust (kN)
520.0
Diameter (mm)
3200
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (≈520 kN) for a single unit, enabling precise manoeuvring of large ships
- Optimised duct geometry reduces cavitation and noise, improving crew comfort and compliance with environmental limits
- Robust stainless‑steel tunnel construction provides long service life in harsh marine environments
- Integrated cooling system allows continuous high‑power operation for DP2/DP3 applications
- Proven design widely used on LNG carriers, cruise ships and offshore support vessels
Weaknesses
- Large diameter (3.2 m) requires significant hull penetration and internal space
- High electrical power demand (≈4 MW) may exceed the capacity of smaller vessel power plants
- Installation and commissioning costs are substantial compared with lower‑power thrusters
- Maintenance access can be challenging due to size and location in the bow tunnel
- Weight and structural reinforcement requirements increase overall ship weight
Typical Vessels:
LNG CarrierCruise ShipOffshore Support Vessel (OSV)Very Large Container ShipBulk Carrier (>80 kt)
Certifications:
DNV
Decision Guide: Choose if the vessel needs high thrust for tight‑berth manoeuvring, dynamic positioning (DP2/DP3) or emergency stopping and has sufficient power generation capacity. Avoid on smaller ships where hull space, power supply or budget constraints make a lower‑power thruster more appropriate.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Brunvoll FU-4000 stern
unverified
· 4000.0 kW
· tunnel thruster
Power (kW)
4000
Thrust (kN)
520.0
Diameter (mm)
3200
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust‑to‑power ratio (520 kN at 4 MW) for its size
- Proven reliability on ultra‑large commercial ships
- Low cavitation design reduces hull wear and noise
- Standard Brunvoll control unit integrates with DP systems
- Class‑approved installation procedures simplify certification
Weaknesses
- High electrical power demand (4 MW) requires robust shipboard supply
- Large tunnel diameter occupies significant hull space
- Water‑cooled stator and pump system increase maintenance complexity
- Weight and structural reinforcement requirements are substantial
- Limited suitability for small or low‑power vessels
Typical Vessels:
Container ships (>10,000 TEU)Cruise linersLNG carriersOffshore supply vesselsFPSOs and large tankers
Certifications:
DNVABS
Decision Guide: Choose if you need very high lateral thrust on a large vessel, have sufficient power generation capacity, and require a compact tunnel solution with proven class approval. Avoid if the vessel is small, power‑limited, or if an azimuth thruster would provide better all‑directional control.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
AR100
Thrust per Hersteller-Datenblatt
· Seawater
· Tunnel thruster
Common Failures & Inspection Points
- Gearbox oil leakage due to shaft seal wear after 15,000–20,000 operating hours
- Propeller blade edge erosion due to cavitation
- Hydraulic motor leakage in hydraulic variants
- Electric motor insulation degradation due to moisture
Service: Gearbox oil analysis every 1,000 operating hours. Motor insulation test annually. Propeller inspection at docking. Tunnel strainer inspection at docking.
Spare Parts: Brunvoll AS: gearbox oil and seals to be kept aboard. Lead time: 3–6 weeks.
Strengths
- DNV‑approved design with documented reliability in commercial service
- Modular construction allows relatively quick installation and replacement of the propeller blade and seal assemblies
- Standardised maintenance regime (oil analysis every 1 000 h, insulation test annually) supports predictable upkeep costs
- Available in both hydraulic and electric drive versions to suit vessel power‑distribution preferences
Weaknesses
- Gearbox oil leaks can develop after 15 000–20 000 operating hours due to seal wear
- Propeller blade edges are prone to cavitation‑induced erosion, requiring periodic inspection at dry‑dock
- Hydraulic drive variants may suffer motor leakage if seals age, increasing maintenance effort
- Electrical versions can experience insulation degradation in high‑humidity environments
Typical Vessels:
Product tanker (up to ~30 000 dwt)Bulk carrier (up to ~40 000 dwt)Container feederOffshore supply vesselPassenger ferry
Certifications:
DNV
Decision Guide: Choose the AR100 when a proven, DNV‑approved tunnel thruster of roughly 100 kW thrust is needed for medium‑size vessels that require reliable docking assistance and have an established maintenance programme. Avoid it on very large ships where higher thrust ratings are required or on vessels operating in extreme humidity without adequate ventilation for the electric motor.
Use Cases: The AR100 is typically installed at the bow or stern of merchant ships to provide sideways thrust during port entry, tight berth manoeuvres, and as an auxiliary aid to dynamic positioning systems on offshore support vessels. It is also used on ferries to improve docking turnaround times.
AR63, AU63, AW63
Thrust per Hersteller-Datenblatt
· Seawater
· Tunnel thruster
Common Failures & Inspection Points
- Gearbox oil leakage due to shaft seal wear after 15,000–20,000 operating hours
- Propeller blade edge erosion due to cavitation
- Hydraulic motor leakage in hydraulic variants
- Electric motor insulation degradation due to moisture
Service: Gearbox oil analysis every 1,000 operating hours. Motor insulation test annually. Propeller inspection at docking. Tunnel strainer inspection at docking.
Spare Parts: Brunvoll AS: gearbox oil and seals to be kept aboard. Lead time: 3–6 weeks.
Strengths
- High thrust density in a relatively short tunnel length, suitable for vessels with limited hull space
- Modular drive options allow selection of electric, hydraulic or azimuth motor to match vessel power architecture
- Robust sealed tunnel design reduces ingress of debris and simplifies dock‑side inspection
- Standardised mounting dimensions simplify retro‑fit on existing hulls
- DNV‑approved design with proven service history in North Sea operations
Weaknesses
- Gearbox oil leakage reported after 15 000–20 000 h of operation, requiring regular oil analysis
- Propeller blade edge erosion from cavitation can reduce efficiency if not monitored
- Hydraulic variants may develop motor seal leaks under high‑cycle duty
- Electric motors are sensitive to moisture; insulation degradation must be tested annually
- Limited thrust range compared with larger external azimuth pods for very large vessels
Typical Vessels:
Coastal tankerFeeder container shipHandysize bulk carrierOffshore supply vesselResearch and survey vessels
Certifications:
DNVIMO Type Approval (when installed per DNV class rules)
Decision Guide: Choose if: you need a compact, high‑thrust tunnel thruster for a vessel with limited hull space and prefer a proven DNV‑approved system; the electric AR63 is ideal when shipboard power is primarily electrical, while AU63 fits hydraulic networks. Avoid if: the vessel requires very high thrust (>200 kN) or prefers an external azimuth pod, or if maintenance intervals for gearbox oil cannot be met.
Use Cases: These thrusters are commonly installed on medium‑size tankers and feeder vessels operating in congested ports where precise low‑speed manoeuvring is critical. They are also used on offshore supply ships that need reliable bow/stern thrust for dynamic positioning in harsh sea states.
AR80A, AR80C, AU/AW80C
Thrust per Hersteller-Datenblatt
· Seawater
· Tunnel thruster
Common Failures & Inspection Points
- Gearbox oil leakage due to shaft seal wear after 15,000–20,000 operating hours
- Propeller blade edge erosion due to cavitation
- Hydraulic motor leakage in hydraulic variants
- Electric motor insulation degradation due to moisture
Service: Gearbox oil analysis every 1,000 operating hours. Motor insulation test annually. Propeller inspection at docking. Tunnel strainer inspection at docking.
Spare Parts: Brunvoll AS: gearbox oil and seals to be kept aboard. Lead time: 3–6 weeks.
Strengths
- Proven reliability with DNV class approval
- Compact installation footprint suitable for medium‑size vessels
- Separate electric and hydraulic variants to match vessel power architecture
- Low vibration and noise levels in the electric version
- Standardised maintenance intervals (oil analysis, motor insulation test)
Weaknesses
- Thrust rating limited compared with larger thruster families; may be undersized for high‑power DP vessels
- Shaft seal wear can cause oil leakage after 15 000–20 000 h of operation
- Cavitation can erode propeller edges if operated at high RPM in low‑flow conditions
- Hydraulic versions add complexity (pump, accumulator) and risk of hydraulic leaks
- Electric motor insulation may degrade in very humid environments
Typical Vessels:
Offshore Supply VesselPlatform Support VesselWorkboat / Utility vesselCoastal ferrySmall tanker or bulk carrier (≤30 000 dwt)
Certifications:
DNV
Decision Guide: Choose if you need a compact, DNV‑approved thruster for medium‑size vessels and value the option of electric or hydraulic drive. Avoid if the vessel requires very high thrust (e.g., large DP‑class tankers) or you want to minimise seal‑related maintenance.
Use Cases: Installed at bow or stern to provide low‑speed manoeuvring assistance during docking, undocking and close‑quarter operations; also used as part of a basic dynamic positioning package on offshore supply vessels.
FU100
Thrust per Hersteller-Datenblatt
· Seawater
· Tunnel thruster
Common Failures & Inspection Points
- Gearbox oil leakage due to shaft seal wear after 15,000–20,000 operating hours
- Propeller blade edge erosion due to cavitation
- Hydraulic motor leakage in hydraulic variants
- Electric motor insulation degradation due to moisture
Service: Gearbox oil analysis every 1,000 operating hours. Motor insulation test annually. Propeller inspection at docking. Tunnel strainer inspection at docking.
Spare Parts: Brunvoll AS: gearbox oil and seals to be kept aboard. Lead time: 3–6 weeks.
Strengths
- Compact tunnel geometry fits easily into limited hull space
- Integrated motor–gearbox unit simplifies installation and alignment
- Standardised mounting allows quick replacement during dry‑dock periods
- Proven track record on offshore supply vessels and coastal ferries
Weaknesses
- Shaft seal wear can cause gearbox oil leakage after 15 000–20 000 h of operation
- Propeller blade edges are prone to cavitation‑induced erosion in high‑load conditions
- Hydraulic variants may develop motor leaks if maintenance is neglected
- Electric versions can suffer insulation degradation when exposed to moisture
Typical Vessels:
Offshore Supply VesselCoastal FerryWorkboat / Utility vesselFeeder Container Ship (up to ~5 000 dwt)Small Cruise Vessel
Decision Guide: Choose the FU100 when you need a reliable, space‑saving thruster for vessels up to medium size and can accommodate routine oil‑analysis and seal inspections. Avoid it on ships requiring very high thrust levels or where continuous operation without scheduled dry‑dock access is mandatory.
Use Cases: The FU100 is normally fitted in the bow or stern tunnel of vessels that operate frequently in ports, narrow channels, or offshore rigs, providing lateral thrust for docking, undocking and low‑speed dynamic positioning assistance.
FU115
Thrust per Hersteller-Datenblatt
· Seawater
· tunnel thruster
Common Failures & Inspection Points
- Gearbox oil leakage due to shaft seal wear after 15,000–20,000 operating hours
- Propeller blade edge erosion due to cavitation
- Hydraulic motor leakage in hydraulic variants
- Electric motor insulation degradation due to moisture
Service: Gearbox oil analysis every 1,000 operating hours. Motor insulation test annually. Propeller inspection at docking. Tunnel strainer inspection at docking.
Spare Parts: Brunvoll AS: gearbox oil and seals to be kept aboard. Lead time: 3–6 weeks.
Strengths
- Proven DNV class approval ensures compliance with international standards
- Modular design allows selection of electric or hydraulic motor to match vessel power strategy
- Compact tunnel footprint suitable for vessels with limited hull space
- Standardised maintenance intervals (oil analysis, insulation testing) simplify service planning
Weaknesses
- Known wear points: shaft seal and propeller edge require replacement after 15‑20 000 h
- Cavitation can cause blade edge erosion if operating at high RPM or low inflow pressure
- Hydraulic versions may develop motor leaks, increasing maintenance effort
- Electrical version sensitive to moisture; insulation degradation must be monitored
Typical Vessels:
Container shipBulk carrierTankerOffshore supply vesselFerry / Ro‑Ro
Certifications:
DNV
Decision Guide: Choose if: you need a reliable, class‑approved thruster with flexible drive options for medium‑size vessels and have an established maintenance regime for seals and blades. Avoid if: the vessel operates at very high thrust demands where cavitation risk is unacceptable or if moisture control on electrical systems cannot be guaranteed.
Use Cases: The FU115 is typically installed in the bow or stern of merchant ships to aid low‑speed docking, undocking, and close‑quarter maneuvering. It is also used as an auxiliary thruster on vessels equipped with dynamic positioning systems where precise lateral thrust is required for station keeping.
FU37
Thrust per Hersteller-Datenblatt
· Seawater
Common Failures & Inspection Points
- Gearbox oil leakage due to shaft seal wear after 15,000–20,000 operating hours
- Propeller blade edge erosion due to cavitation
- Hydraulic motor leakage in hydraulic variants
- Electric motor insulation degradation due to moisture
Service: Gearbox oil analysis every 1,000 operating hours. Motor insulation test annually. Propeller inspection at docking. Tunnel strainer inspection at docking.
Spare Parts: Brunvoll AS: gearbox oil and seals to be kept aboard. Lead time: 3–6 weeks.
Strengths
- DNV‑approved design offering class society acceptance
- Modular construction allows installation as either bow or stern unit
- Both hydraulic and electric drive variants available to match vessel power strategy
- Straightforward maintenance regime (oil analysis every 1,000 h, annual motor insulation test)
- Proven track record on a variety of commercial vessels
Weaknesses
- Shaft seal wear leading to oil leakage after roughly 15‑20 k operating hours
- Propeller blade edge erosion caused by cavitation in high‑load conditions
- Hydraulic versions prone to motor oil leaks if seals are not refreshed timely
- Electric motors can suffer insulation degradation when exposed to moisture
Typical Vessels:
Container shipsBulk carriersTanker vesselsOffshore supply vesselsGeneral cargo and feeder ships
Certifications:
DNV
Decision Guide: Choose if: you need a class‑approved tunnel thruster with flexible drive options, have an established maintenance programme (oil analysis, seal replacement) and operate vessels that require reliable low‑speed manoeuvring. Avoid if: the vessel will run continuously at high thrust levels where cavitation is severe, or if operating environments make frequent moisture exposure likely without adequate motor protection.
Use Cases: The FU37 is typically installed on commercial ships to assist with docking, undocking and close‑quarter manoeuvres, especially in ports with limited berth space. It also supports dynamic positioning systems on offshore support vessels where precise lateral thrust is required.
FU45
Thrust per Hersteller-Datenblatt
· Seawater
· tunnel thruster
Common Failures & Inspection Points
- Gearbox oil leakage due to shaft seal wear after 15,000–20,000 operating hours
- Propeller blade edge erosion due to cavitation
- Hydraulic motor leakage in hydraulic variants
- Electric motor insulation degradation due to moisture
Service: Gearbox oil analysis every 1,000 operating hours. Motor insulation test annually. Propeller inspection at docking. Tunnel strainer inspection at docking.
Spare Parts: Brunvoll AS: gearbox oil and seals to be kept aboard. Lead time: 3–6 weeks.
Strengths
- Robust cast‑iron tunnel and shaft line suitable for harsh sea conditions
- Proven DNV class approval for both hydraulic and electric drive versions
- Relatively low installation space requirement compared with azimuth pods of similar thrust
- Modular design allows easy conversion between hydraulic and electric motor variants
Weaknesses
- Wear of shaft seals can lead to gear‑oil leakage after 15 000–20 000 operating hours
- Propeller blade edges are prone to cavitation‑induced erosion if operated at high RPM in low‑flow conditions
- Hydraulic versions may suffer from fluid leaks; electric versions require strict moisture control for motor insulation
- Tunnel geometry can generate additional hull resistance, slightly reducing fuel efficiency
Typical Vessels:
Container ships (5 000–30 000 dwt)General cargo vesselsOffshore supply and support vesselsCruise ships up to mid‑sizeBulk carriers (up to ~30 000 dwt)
Certifications:
DNV
Decision Guide: Choose if you need a reliable, class‑approved thruster for medium‑sized vessels that operate frequently in confined ports and can accommodate either hydraulic or electric drive. Avoid if the vessel requires ultra‑low noise, zero‑leakage solutions, or if hull form optimisation makes tunnel resistance unacceptable.
Use Cases: The FU45 is typically installed on new builds or retrofits where enhanced low‑speed maneuverability is required – e.g., container ships navigating tight terminals, offshore supply vessels needing precise station‑keeping, and cruise ships docking in crowded harbours. Its modular drive options make it suitable for operators transitioning from hydraulic to electric propulsion while retaining a familiar tunnel thruster footprint.
FU63
Thrust per Hersteller-Datenblatt
· Seawater
· Tunnel thruster
Common Failures & Inspection Points
- Gearbox oil leakage due to shaft seal wear after 15,000–20,000 operating hours
- Propeller blade edge erosion due to cavitation
- Hydraulic motor leakage in hydraulic variants
- Electric motor insulation degradation due to moisture
Service: Gearbox oil analysis every 1,000 operating hours. Motor insulation test annually. Propeller inspection at docking. Tunnel strainer inspection at docking.
Spare Parts: Brunvoll AS: gearbox oil and seals to be kept aboard. Lead time: 3–6 weeks.
Strengths
- Compact installation footprint suitable for vessels with limited hull space
- High thrust output relative to size, aiding precise low‑speed manoeuvring
- Proven track record in offshore and commercial fleets
- Modular hydraulic or electric drive options
Weaknesses
- Shaft seal wear leading to gearbox oil leakage after ~15 000–20 000 h
- Propeller blade edge erosion from cavitation over time
- Hydraulic variants prone to motor leaks if maintenance is lax
- Electric motor insulation can degrade in high‑humidity environments
Typical Vessels:
Offshore supply vesselFerryContainer shipBulk carrierTugboat
Decision Guide: Choose if the vessel requires strong lateral thrust in confined ports, has a shallow draft, and can accommodate regular seal‑oil analysis and propeller inspections. Avoid if maintenance intervals cannot be met or if the operating environment is highly corrosive, increasing risk of seal and motor degradation.
Use Cases: The FU63 is commonly fitted on vessels that need reliable bow or stern thrust for docking, undocking, low‑speed manoeuvring in tight waterways, and as an auxiliary aid to dynamic positioning systems.
FU74
Thrust per Hersteller-Datenblatt
· Seawater
· hydraulic tunnel thruster
Common Failures & Inspection Points
- Gearbox oil leakage due to shaft seal wear after 15,000–20,000 operating hours
- Propeller blade edge erosion due to cavitation
- Hydraulic motor leakage in hydraulic variants
- Electric motor insulation degradation due to moisture
Service: Gearbox oil analysis every 1,000 operating hours. Motor insulation test annually. Propeller inspection at docking. Tunnel strainer inspection at docking.
Spare Parts: Brunvoll AS: gearbox oil and seals to be kept aboard. Lead time: 3–6 weeks.
Strengths
- Proven DNV class approval ensures compliance with international standards
- Compact tunnel design fits into limited hull space while delivering high thrust
- Modular motor option (hydraulic or electric) allows flexibility for vessel power strategy
- Straightforward maintenance regime – oil analysis every 1,000 h and annual insulation testing
- Robust gear housing with accessible seals for relatively easy replacement
Weaknesses
- Gear oil leakage can occur after 15‑20 k operating hours due to seal wear
- Propeller blade edge erosion from cavitation is reported in high‑speed service
- Hydraulic variants may develop motor leaks, requiring vigilant monitoring of hydraulic fluid
- Electrical versions are sensitive to moisture; insulation degradation has been observed
Typical Vessels:
Container shipTankerBulk carrierCruise linerOffshore supply vessel
Certifications:
DNV
Decision Guide: Choose if: you need a reliable, class‑approved thruster for vessels up to ~150 m LOA with limited hull space and prefer a proven hydraulic drive or an optional electric motor. Avoid if: the vessel operates in extreme cavitation environments where blade erosion would be critical, or if moisture‑prone electrical installations cannot guarantee long‑term insulation integrity.
Use Cases: The FU74 is typically installed on new builds and retrofits of medium‑size cargo ships and cruise vessels to improve docking precision, low‑speed maneuvering in ports, and dynamic positioning support where lateral thrust is required without sacrificing hull strength.
FU80
Thrust per Hersteller-Datenblatt
· Seawater
· tunnel thruster
Common Failures & Inspection Points
- Gearbox oil leakage due to shaft seal wear after 15,000–20,000 operating hours
- Propeller blade edge erosion due to cavitation
- Hydraulic motor leakage in hydraulic variants
- Electric motor insulation degradation due to moisture
Service: Gearbox oil analysis every 1,000 operating hours. Motor insulation test annually. Propeller inspection at docking. Tunnel strainer inspection at docking.
Spare Parts: Brunvoll AS: gearbox oil and seals to be kept aboard. Lead time: 3–6 weeks.
Strengths
- High thrust‑to‑power ratio in a relatively small tunnel envelope
- Modular design allows selection of hydraulic or electric motor per vessel preference
- DNV class approval provides recognised safety and reliability standards
- Accessible gear housing enables routine oil analysis every 1,000 h as recommended
Weaknesses
- Gear‑oil leakage reported after 15–20 k operating hours due to shaft seal wear
- Propeller blade edge erosion from cavitation in high‑load conditions
- Hydraulic motor versions can develop leaks in the hydraulic circuit over time
- Electric motor insulation may degrade in humid environments, requiring annual testing
Typical Vessels:
Offshore supply vesselAnchor handling tug supply (AHTS)Platform support vesselMultipurpose workboat
Certifications:
DNV
Decision Guide: Choose the FU80 when a compact, DNV‑approved thruster with flexible drive options is needed for vessels that operate frequently in ports or close to offshore installations. Avoid if the vessel requires very high thrust levels beyond the FU80’s rating or if operating conditions make frequent seal maintenance impractical.
Use Cases: Commonly installed on offshore support ships and supply vessels to provide precise low‑speed manoeuvring during docking, anchor handling, and dynamic positioning tasks where space for a larger thruster is limited.
FU93
Thrust per Hersteller-Datenblatt
· Seawater
· Tunnel thruster
Common Failures & Inspection Points
- Gearbox oil leakage due to shaft seal wear after 15,000–20,000 operating hours
- Propeller blade edge erosion due to cavitation
- Hydraulic motor leakage in hydraulic variants
- Electric motor insulation degradation due to moisture
Service: Gearbox oil analysis every 1,000 operating hours. Motor insulation test annually. Propeller inspection at docking. Tunnel strainer inspection at docking.
Spare Parts: Brunvoll AS: gearbox oil and seals to be kept aboard. Lead time: 3–6 weeks.
Strengths
- High thrust‑to‑power ratio suitable for large vessels
- Modular design allows selection of electric or hydraulic motor
- Robust gear set with documented service life up to 20 000 operating hours
- Low vibration and noise levels compared with external azimuth thrusters
- Easy access for routine maintenance (oil analysis, propeller inspection)
Weaknesses
- Gear oil leakage can occur after 15‑20 000 h due to shaft seal wear
- Propeller blade edge erosion from cavitation is a known issue
- Hydraulic versions may develop motor leaks over time
- Electric motor insulation degrades in high‑humidity environments
- Tunnel grille requires inspection and cleaning at each docking
Typical Vessels:
Container shipBulk carrierTankerCruise linerOffshore supply vessel
Certifications:
DNV
Decision Guide: Choose if you need a proven, high‑thrust tunnel thruster with flexible drive options and can accommodate regular oil analysis and grille inspections. Avoid if operating in extremely humid climates without adequate ventilation or if maintenance windows cannot support the recommended 1 000‑hour service intervals.
Use Cases: The FU93 is commonly installed on newbuilds requiring strong lateral thrust for port entry/exit, dynamic positioning of offshore vessels, and maneuvering of large tankers or container ships in confined waterways. Its modular drive makes it suitable for both electric‑driven DP systems and hydraulic‑driven conventional setups.
Kongsberg
45
TT-100 bow
· 100.0 kW
· hydraulic tunnel thruster
Power (kW)
100
Thrust (kN)
12.0
Diameter (mm)
580
Type
tunnel
Location
bow
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- High thrust‑to‑power ratio (12 kN @ 100 kW) for its compact 580 mm diameter
- Proven Kongsberg reliability and integration with standard control consoles
- Sealed hydraulic system reduces oil leakage risk and simplifies maintenance
- Relatively low installation space requirement, suitable for vessels with limited hull opening
Weaknesses
- Fixed‑direction thrust; no 360° azimuth capability
- Maximum thrust may be insufficient for large vessels or strong cross‑currents
- Tunnel geometry can increase local hull resistance and affect fuel efficiency at higher speeds
- Not certified for ice‑class operations
Typical Vessels:
Product tanker (up to ~30 000 dwt)Handymax bulk carrierOffshore supply vesselMedium‑size container shipFerry or cruise‑ship tender
Certifications:
DNV GL Approved EquipmentABS Type ApprovalIMO Type Approval (general thruster class)
Decision Guide: Choose if the vessel needs a compact bow thruster with up to 12 kN thrust, operates in temperate ports, has a limited power budget (~100 kW) and does not require azimuth steering or ice‑class capability. Avoid if higher thrust (>20 kN), 360° maneuverability, or ice‑strengthened operation is required.
Use Cases: Typical deployments include port entry/exit of product tankers and offshore supply vessels, tight‑berth handling for medium‑size ferries, and low‑speed docking maneuvers for cruise‑ship tenders in confined harbours.
TT-100 stern
· 100.0 kW
· Tunnel thruster
Power (kW)
100
Thrust (kN)
12.0
Diameter (mm)
580
Type
tunnel
Location
stern
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- Compact 580 mm tunnel fits vessels with limited hull space
- High thrust‑to‑power ratio (12 kN @ 100 kW) for efficient bollard pull
- Proven Kongsberg hydraulic drive offers reliable service life
- Low acoustic signature and vibration compared with open‑propeller units
- Straightforward retrofit into existing stern tunnels
Weaknesses
- Maximum thrust of 12 kN may be insufficient for large vessels or high‑speed DP operations
- Fixed‑pitch propeller limits thrust vector flexibility versus azimuth thrusters
- Hydraulic system requires regular oil monitoring and periodic seal replacement
- Cavitation risk in shallow water at high RPMs
- Limited scalability – not suitable for vessels requiring >200 kW power
Typical Vessels:
Coastal tanker (≤30,000 DWT)Offshore supply vessel (OSV)Ferry / Ro‑RoWorkboat / Tug auxiliarySmall cruise‑ship tender
Certifications:
IMO Type Approval (D‑2)
Decision Guide: Choose if the ship needs modest stern thrust, has restricted tunnel dimensions and already uses hydraulic power; budget and simplicity are priorities. Avoid if high maneuverability, large bollard pull, or 360° thrust vectoring is required, as an azimuth or permanent‑magnet thruster would be more appropriate.
Use Cases: Commonly installed in the stern tunnels of medium‑size tankers and offshore supply vessels to aid low‑speed docking, harbor turns, and limited dynamic positioning. Also fitted on ferries for quick port entry/exit where space and weight are at a premium.
TT-150 bow
· 150.0 kW
· Tunnel Thruster
Power (kW)
150
Thrust (kN)
18.0
Diameter (mm)
620
Type
tunnel
Location
bow
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- Compact 620 mm duct fits vessels with limited hull space
- High thrust‑to‑power ratio (18 kN at 150 kW) for medium‑size ships
- Proven Kongsberg reliability and extensive service network
- Standardised hydraulic system simplifies integration and maintenance
- Well‑documented inspection points and failure modes
Weaknesses
- Fixed‑pitch tunnel design offers less directional flexibility than azimuth units
- Maximum thrust (18 kN) may be insufficient for large tankers or high‑wind conditions
- Hull penetration required, increasing installation complexity and potential for vibration
- Lower overall efficiency compared with modern rim‑drive or permanent‑magnet thrusters
Typical Vessels:
Product tanker (up to ~30 000 dwt)Bulk carrier (handymax class)Container feederOffshore supply vesselCruise ship auxiliary (mid‑size)
Decision Guide: Choose if you need a reliable, compact bow thruster for medium‑sized vessels where hull space is limited and moderate thrust (≈18 kN) suffices for docking or low‑speed manoeuvring. Avoid if the vessel requires higher thrust levels, full 360° azimuth capability, or the most energy‑efficient solution available.
Use Cases: The TT‑150 is typically installed on vessels that operate in confined ports or narrow waterways, providing lateral thrust during berthing, unberthing and low‑speed manoeuvres. It also supports limited dynamic positioning tasks on offshore support ships where a full DP system is not required.
TT-150 stern
· 150.0 kW
· Tunnel Thruster
Power (kW)
150
Thrust (kN)
18.0
Diameter (mm)
620
Type
tunnel
Location
stern
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- Compact installation envelope (620 mm duct) fits vessels with limited hull space.
- High thrust‑to‑power ratio for a 150 kW unit, delivering 18 kN of lateral force.
- Proven Kongsberg hydraulic control system with built‑in diagnostics and fault monitoring.
- Standardised mounting interface simplifies retrofit on existing stern sections.
- Robust double‑gear hydraulic drive reduces wear and extends service intervals.
Weaknesses
- Fixed‑direction thrust; requires separate bow thruster for full DP capability.
- Thrust limited to ~18 kN, which may be insufficient for very large tankers or ice‑class vessels.
- Hydraulic system adds complexity compared with electric tunnel thrusters (e.g., PM models).
- Propeller blades are prone to marine growth and require regular cleaning in warm waters.
- No built‑in ice protection; not suitable for high‑ice environments without additional measures.
Typical Vessels:
Container ships (up to ~5,000 TEU)General cargo vesselsMedium‑size tankers (up to ~30,000 DWT)Bulk carriers (up to ~40,000 DWT)Offshore supply and support vessels
Decision Guide: Choose if you need a reliable, space‑efficient stern thruster for vessels up to medium size where 18 kN thrust meets manoeuvring requirements and hydraulic control is preferred. Avoid on ships requiring higher thrust, full azimuth capability at the stern, or operation in heavy ice conditions.
Use Cases: Installed on the stern of container, bulk carrier and tanker hulls to provide lateral thrust during docking, undocking, low‑speed port turns, and as a supplemental thruster for dynamic positioning systems on DP2 vessels. Frequently used where a compact ducted solution is required without sacrificing significant bollard pull.
TT-200 bow
· 200.0 kW
· hydraulic tunnel thruster
Power (kW)
200
Thrust (kN)
24.0
Diameter (mm)
660
Type
tunnel
Location
bow
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- High thrust‑to‑power ratio (24 kN @ 200 kW) for its compact size
- Small tunnel diameter (660 mm) fits vessels with limited hull space
- Proven Kongsberg reliability and extensive global support network
- Standardised hydraulic control system simplifies integration with existing HPUs
- Easy access for routine inspection of propeller blades and seals
Weaknesses
- Maximum thrust (24 kN) may be insufficient for high‑bollard‑pull or DP‑2 applications
- Fixed‑pitch tunnel design can generate hull vibration and drag when not in use
- Requires a dedicated hydraulic power unit, adding weight and space requirements
- Not rated for ice‑class operations; unsuitable for Arctic service
- Non‑retractable installation limits flexibility on vessels that need reduced draft
Typical Vessels:
Handymax bulk carrierProduct tanker (≤30 kt)Offshore supply vesselContainer feederCruise ship (mid‑size) for bow maneuvering
Certifications:
DNV GL Class Approval
Decision Guide: Choose if the vessel needs moderate bow thrust (~24 kN), has limited hull space, operates in temperate waters and already uses a hydraulic power system. Avoid if high bollard‑pull (>30 kN), ice‑class capability, or retractable thruster geometry is required.
Use Cases: The TT‑200 is typically installed on medium‑size commercial ships for port entry/exit, tight berth handling, and low‑speed dynamic positioning (DP0/1). It also serves as an auxiliary thrust source on offshore supply vessels during anchor handling or emergency maneuvers.
TT-200 stern
· 200.0 kW
· hydraulic tunnel thruster
Power (kW)
200
Thrust (kN)
24.0
Diameter (mm)
660
Type
tunnel
Location
stern
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- High thrust‑to‑power ratio for its size (24 kN @ 200 kW)
- Compact tunnel housing fits in limited hull space
- Proven Kongsberg hydraulic drive with built‑in redundancy
- Standardised mounting and control interface simplifies integration
- Low initial cost compared with azimuth thrusters of similar power
Weaknesses
- Limited maneuverability – fixed thrust direction only
- Lower total thrust than comparable azimuth units, unsuitable for high‑power DP
- Tunnel flow can increase hull resistance and affect fuel efficiency at higher speeds
- Maintenance intensive seals and bearing wear require regular inspection
- Less effective in very shallow water where tunnel inlet may be partially blocked
Typical Vessels:
Product tanker (up to ~30 000 dwt)Offshore supply vesselCoastal container shipFerry / Ro‑RoSmall cruise‑ship tender
Certifications:
DNV Class Approval
Decision Guide: Choose if you need a cost‑effective, compact stern thruster for vessels up to medium size where fixed thrust is sufficient and budget constraints dominate. Avoid if the vessel requires high maneuverability (e.g., dynamic positioning), very high bollard pull, or operates in extremely shallow water where tunnel blockage is a risk.
Use Cases: The TT‑200 is typically installed on the stern of small to medium commercial vessels to provide docking assistance, low‑speed port manoeuvring, emergency bollard‑pull capability and as a backup propulsion aid for ships that rely primarily on main propellers.
TT-250 bow
· 250.0 kW
· hydraulic tunnel thruster
Power (kW)
250
Thrust (kN)
30.0
Diameter (mm)
700
Type
tunnel
Location
bow
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- High thrust‑to‑power ratio (30 kN @ 250 kW) for its size
- Compact 700 mm tunnel fits vessels with limited hull space
- Proven Kongsberg reliability and double‑gear hydraulic drive reduces wear
- Integrated monitoring compatible with ship automation systems
- Suitable for a wide range of medium‑size commercial ships
Weaknesses
- Hydraulic system requires regular oil maintenance and leak checks
- Limited azimuth range compared with full‑circle azimuth thrusters
- Lower overall efficiency than newer permanent‑magnet electric units
- Potential fouling of the propeller blades in low‑speed, high‑biofouling areas
- Maximum thrust (30 kN) may be insufficient for very large vessels or heavy DP requirements
Typical Vessels:
Product tankers (10–30 kt)Handymax / Supramax bulk carriersOffshore supply vesselsCruise ship tenders and small cruise shipsContainer feeders up to ~5,000 TEU
Certifications:
DNV GL class approvalABS classification
Decision Guide: Choose if you need a compact, proven hydraulic bow thruster delivering around 30 kN for vessels up to roughly 40 kt and operate in ports where space is limited and maintenance infrastructure for hydraulics exists. Avoid if you require higher thrust, full 360° azimuth capability, or want the energy‑efficiency benefits of an electric permanent‑magnet unit.
Use Cases: The TT‑250 is typically installed on medium‑size merchant ships to provide precise low‑speed manoeuvring during port entry/exit, docking, and tug‑assist operations. It also supports limited dynamic positioning tasks on offshore supply vessels where a modest bow thrust contribution is sufficient.
TT-250 stern
· 250.0 kW
· Tunnel thruster
Power (kW)
250
Thrust (kN)
30.0
Diameter (mm)
700
Type
tunnel
Location
stern
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- High thrust‑to‑power ratio (30 kN @ 250 kW) for its size
- Robust double‑gear hydraulic drive with built‑in redundancy
- Compact 700 mm propeller diameter fits narrow hull sections
- Proven Kongsberg control integration with DP systems
- Standardised maintenance points and spare‑part availability
Weaknesses
- Fixed‑pitch propeller limits thrust optimisation across speed range
- No 360° azimuth capability – only straight‑line thrust
- Maximum thrust may be insufficient for large tankers or ice‑class vessels
- Hydraulic system adds complexity compared with fully electric rim‑drive units
Typical Vessels:
Handymax bulk carrierProduct tanker (≤30 kton)Offshore supply vesselSmall cruise shipResearch / survey vessel
Decision Guide: Choose if: you need a reliable, space‑efficient stern thruster for vessels up to ~30 kN thrust, especially where integration with existing Kongsberg DP control is required. Avoid if: the ship demands higher thrust (>100 kN), azimuth steering, or operation in heavy ice conditions where an Arctic or rim‑drive thruster would be more appropriate.
Use Cases: The TT‑250 is typically installed on medium‑size commercial ships to provide bow‑/stern‑side assistance during docking, undocking and low‑speed manoeuvres in confined ports. It is also used as a secondary DP actuator on vessels that already have main azimuth thrusters, offering redundancy for dynamic positioning.
TT-300 bow
· 300.0 kW
· hydraulic tunnel thruster
Power (kW)
300
Thrust (kN)
36.0
Diameter (mm)
740
Type
tunnel
Location
bow
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- Compact 740 mm tunnel fits vessels with limited hull space.
- High thrust‑to‑power ratio (36 kN @ 300 kW) suitable for medium‑size ships.
- Proven Kongsberg/ Rolls‑Royce reliability and worldwide service network.
- Standard hydraulic drive integrates easily with existing ship systems.
- Well‑documented inspection and maintenance procedures.
Weaknesses
- Fixed‑pitch propeller is less efficient than azimuth or permanent‑magnet designs.
- Provides only lateral thrust; no 360° steering capability.
- Requires hull penetration and reinforcement, increasing leak risk.
- Not rated for heavy ice conditions or extreme DP loads.
- Higher noise and vibration compared with rim‑drive thrusters.
Typical Vessels:
Container shipBulk carrierGeneral cargo vesselRo‑Ro ferryOffshore supply vesselCruise ship
Certifications:
DNV GLABS
Decision Guide: Choose if you need a reliable, compact bow thruster with moderate power (≈300 kW) for vessels up to ~150 m LOA that have limited hull space and do not require full 360° thrust. Avoid if the vessel operates in ice‑class conditions, requires maximum efficiency (e.g., permanent‑magnet or rim‑drive units), or needs omnidirectional thrust for advanced dynamic positioning.
Use Cases: The TT‑300 is typically installed on the bow of medium‑size merchant ships to provide low‑speed maneuvering assistance during port entry/exit, docking, and close‑quarter operations. It also supports limited dynamic positioning tasks on offshore supply vessels or cruise ships that do not have a full DP system.
TT-300 stern
· 300.0 kW
· hydraulic tunnel thruster
Power (kW)
300
Thrust (kN)
36.0
Diameter (mm)
740
Type
tunnel
Location
stern
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- Compact 740 mm duct fits in medium‑size hulls without excessive structural reinforcement
- High thrust‑to‑power ratio (36 kN at 300 kW) for vessels up to ~150 m LOA
- Proven Kongsberg reliability and worldwide spare‑parts support
- Standardised hydraulic control system simplifies integration with existing ship automation
- Well‑documented inspection and maintenance procedures (propeller blades, shaft seal, bearings, hydraulics)
Weaknesses
- Provides only transverse thrust; no 360° azimuth capability for advanced DP manoeuvring
- Hull suction can reduce efficiency in heavy seas or when operating near the bow/stern
- Installation requires hull penetration and internal duct space, increasing dry‑dock time
- Potential cavitation noise at high RPMs, which may be a concern for passenger vessels
- Hydraulic system adds maintenance overhead compared with electric PM thrusters
Typical Vessels:
Medium‑size tankers (up to ~30 kt)Container ships (up to ~150 m length)Bulk carriers (handymax class)Cruise liners (mid‑size) Offshore supply vessels
Certifications:
IMO Type ApprovalDNV Class approval
Decision Guide: Choose the TT‑300 when a cost‑effective, compact lateral thrust solution is needed for medium‑sized commercial ships that require reliable docking assistance but do not need full azimuth manoeuvring or high‑power DP capability. Avoid it on vessels requiring ice‑class operation, high‑speed dynamic positioning, or where noise and vibration must be minimised, in which case an electric permanent‑magnet or azimuth thruster may be more suitable.
Use Cases: The TT‑300 is typically installed on the stern of tankers, container ships and bulk carriers to aid low‑speed manoeuvring in ports, assist with berthing against cross‑currents, and provide supplemental thrust for emergency steering. It is also used on cruise ships and offshore supply vessels where space constraints favour a tunnel layout over an azimuth unit.
TT-400 bow
· 400.0 kW
· hydraulic tunnel thruster
Power (kW)
400
Thrust (kN)
48.0
Diameter (mm)
820
Type
tunnel
Location
bow
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- High thrust‑to‑power ratio (48 kN @ 400 kW) for effective bow assistance
- Compact 820 mm tunnel diameter fits vessels with limited hull space
- Robust double‑gear hydraulic drive reduces risk of sudden failure
- Low acoustic and vibration signature, helping meet port noise limits
- Integrated condition monitoring compatible with Kongsberg Vessel Insight
Weaknesses
- Fixed‑pitch propeller offers less fine thrust control than azimuth units
- Hydraulic system requires regular oil maintenance and leak checks
- Bow installation is exposed to grounding damage in shallow ports
- Maximum thrust may be insufficient for very large vessels (>30,000 dwt) needing higher bollard pull
Typical Vessels:
Container shipBulk carrierGeneral cargo vesselRo‑Ro ferryOffshore supply vessel
Certifications:
DNV
Decision Guide: Choose the TT‑400 when you need a compact, high‑thrust bow thruster for vessels up to about 30 000 dwt and value proven hydraulic reliability with integrated monitoring. Avoid it on ice‑class ships, ultra‑large vessels requiring >60 kN thrust, or where an electric permanent‑magnet unit would simplify maintenance.
Use Cases: The TT‑400 is typically installed in the bow tunnel of medium‑size merchant ships to provide precise low‑speed manoeuvring during port entry/exit, assist dynamic positioning on offshore supply vessels, and support emergency stop maneuvers where high thrust is required but space is limited.
TT-400 stern
· 400.0 kW
· Tunnel thruster
Power (kW)
400
Thrust (kN)
48.0
Diameter (mm)
820
Type
tunnel
Location
stern
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- High thrust‑to‑power ratio for its size (48 kN at 400 kW)
- Compact tunnel diameter (820 mm) fits vessels with limited hull space
- Proven Kongsberg reliability and global service network
- Standardised hydraulic interface simplifies integration and maintenance
- Suitable for retro‑fit installations on existing ships
Weaknesses
- Fixed‑direction thrust; no azimuth swing for lateral manoeuvring
- Lower maximum bollard‑pull compared with larger azimuth thrusters of similar power
- Installation requires hull penetration and structural reinforcement
- Potential cavitation noise at high RPM, which may affect passenger comfort on cruise vessels
- Hydraulic system adds complexity versus electric tunnel units
Typical Vessels:
Product tanker (up to ~30 000 dwt)Container ship (up to ~5 000 TEU)Cruise ship (mid‑size, up to ~150 m length)Offshore supply vesselMultipurpose bulk carrier
Decision Guide: Choose if the vessel needs a reliable, space‑efficient stern thruster for low‑speed manoeuvring or DP assistance and budget constraints limit the use of full azimuth units. Avoid if 360° thrust vectoring, very high bollard pull, or ultra‑quiet operation are mandatory.
Use Cases: The TT‑400 is typically installed on medium‑size tankers, container ships and cruise vessels to aid docking, undocking and low‑speed manoeuvres in confined ports; it also serves as a secondary thruster on offshore supply vessels that require limited dynamic positioning capability without the cost of full azimuth systems.
TT-500 bow
· 500.0 kW
· hydraulic fixed‑pitch tunnel thruster
Power (kW)
500
Thrust (kN)
60.0
Diameter (mm)
900
Type
tunnel
Location
bow
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- High thrust‑to‑power ratio (60 kN from 500 kW) for its size
- Compact 900 mm tunnel diameter fits vessels with limited hull space
- Proven Kongsberg reliability and global after‑sales support
- Integrated monitoring compatible with Kongsberg ship control systems
Weaknesses
- Fixed‑pitch design – no 360° azimuth capability
- Requires dedicated hydraulic power pack, adding system complexity
- Thrust limited compared with larger 800–1000 kW thrusters for very large vessels
- Maintenance of shaft seals and hydraulic components is critical
Typical Vessels:
Medium‑size container ships (up to ~8,000 TEU)Bulk carriers (30–50 kt)Product tankers (20–40 kt)Ro‑Ro vesselsOffshore support vessels
Certifications:
IMO Type Approval
Decision Guide: Choose if you need a moderate‑power bow thruster with high thrust density for vessels up to ~50 kt and have limited hull space. Avoid if the vessel requires very high bollard‑pull, azimuth steering, or wants to minimise hydraulic system complexity.
Use Cases: Commonly installed on newbuilds and retrofits to improve port manoeuvrability, especially where a compact bow tunnel is required for tight berthing situations in congested ports.
TT-500 stern
· 500.0 kW
· hydraulic tunnel thruster
Power (kW)
500
Thrust (kN)
60.0
Diameter (mm)
900
Type
tunnel
Location
stern
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- Compact 0.9 m duct size fits in medium‑sized hull forms
- High thrust‑to‑power ratio for a conventional tunnel design (60 kN @ 500 kW)
- Proven Kongsberg hydraulic control system with built‑in diagnostics
- Standardised mounting and spare parts across the TT product line
- Ease of installation on new builds and retrofits
Weaknesses
- Fixed‑pitch propeller limits thrust optimisation at varying speeds
- Hydraulic drive adds maintenance overhead compared with direct‑drive PM thrusters
- Maximum thrust (60 kN) may be insufficient for large DP‑class vessels or ice‑strengthened ships
- No 360° azimuth capability – only provides transverse force
Typical Vessels:
Offshore supply vesselCruise ship (mid‑size)Container feederGeneral cargo / RoRo ferryMedium‑size tanker or bulk carrier (up to ~150 k DWT)
Certifications:
DNV GL class approvalABS class approval
Decision Guide: Choose if you need a reliable, compact stern thruster delivering up to 60 kN for vessels up to about 150 k DWT where cost and proven hydraulic technology are priorities. Avoid if the vessel requires higher thrust, energy‑efficient PM or azimuth solutions, or full 360° maneuverability for high‑DP operations.
Use Cases: The TT‑500 is typically installed on offshore support ships for low‑speed docking assistance, on cruise vessels to aid stern‑first manoeuvring in port, and on medium‑size container or tanker ships where a single stern thruster improves berth handling without the expense of an azimuth unit.
TT-600 bow
· 600.0 kW
· hydraulic‑driven tunnel thruster
Power (kW)
600
Thrust (kN)
72.0
Diameter (mm)
980
Type
tunnel
Location
bow
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- High thrust output (72 kN) in a relatively compact 980 mm duct suitable for deep‑draft ships
- Proven Kongsberg reliability and extensive global support network
- Integrated double‑gear hydraulic drive offers smooth, precise thrust control
- Lower upfront cost compared with comparable azimuth thrusters of the same power
- Standardised hull penetration kit simplifies installation on new builds or retrofits
Weaknesses
- Fixed‑direction thrust; requires separate steering gear for yawing, limiting maneuverability versus a 360° azimuth unit
- Hull penetration creates potential points for corrosion and water ingress if not maintained
- Hydraulic system can be noisier and generate more vibration than electric PM thrusters
- Slightly lower overall propulsive efficiency at very low speeds compared with permanent‑magnet designs
- Maintenance of hydraulic seals and bearings is required on a 5‑year overhaul cycle
Typical Vessels:
Container ships (>8 000 TEU)Very Large Crude Carriers (VLCC) and Suezmax tankersCruise linersLNG carriersOffshore supply vessels and platform support ships
Certifications:
DNVABSLR
Decision Guide: Choose if you need high bow thrust for a large vessel, have limited deck‑space for an azimuth unit, and want a cost‑effective solution with proven service support. Avoid if the ship requires full 360° thrust vectoring, ultra‑quiet operation, or minimal hull penetrations for ice‑class or highly regulated vessels.
Use Cases: The TT‑600 is typically installed on deep‑draft, high‑displacement ships to provide powerful bow assistance during port entry/exit, tight berthing maneuvers, and as an auxiliary thrust source for dynamic positioning when combined with stern thrusters. It is also used on retrofits where space constraints preclude larger azimuth installations.
TT-600 stern
· 600.0 kW
· Tunnel Thruster
Power (kW)
600
Thrust (kN)
72.0
Diameter (mm)
980
Type
tunnel
Location
stern
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- High thrust‑to‑power ratio (72 kN @ 600 kW) for rapid low‑speed manoeuvre
- Compact tunnel diameter (980 mm) fits into limited hull space
- Proven Kongsberg reliability with double‑gear hydraulic drive and built‑in redundancy
- Straight‑through flow reduces cavitation risk compared to smaller units
- Standardised mounting kit simplifies retro‑fit on existing stern sections
Weaknesses
- Fixed thrust direction – no azimuth capability, limiting lateral control
- Hull penetration required; structural reinforcement adds installation cost
- Shaft seal and bearing wear demand regular inspection (5‑year overhaul typical)
- Lower overall propulsive efficiency than rim‑drive or azimuth thrusters at very low speeds
- Hydraulic system generates noise/vibration that may affect crew comfort
Typical Vessels:
Container shipBulk carrierProduct tankerOffshore supply vesselCruise liner (stern‑assist)
Certifications:
IMO Type ApprovalDNV GL Class Approval
Decision Guide: Choose if you need a robust, high‑thrust stern thruster for vessels up to ~150 m LOA where space is limited and azimuth capability is not required. Avoid if the vessel requires 360° thrust vectoring, ultra‑low noise operation, or maximum propulsive efficiency at very low speeds.
Use Cases: The TT‑600 is commonly installed on medium‑size cargo ships and offshore vessels to provide bow‑or stern‑assist during docking, undocking, and low‑speed manoeuvring in confined ports. It also serves as a secondary thruster for DP‑2/DP‑3 systems where primary azimuth units handle the main thrust vectoring.
TT-750 bow
· 750.0 kW
· hydraulic tunnel thruster
Power (kW)
750
Thrust (kN)
90.0
Diameter (mm)
1100
Type
tunnel
Location
bow
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- High thrust‑to‑power ratio (90 kN @ 750 kW) for strong low‑speed manoeuvring
- Compact tunnel diameter (1.1 m) fits into limited hull space
- Proven Kongsberg hydraulic drive with built‑in redundancy and fast response
- Standardised maintenance points; easy access to propeller, seals and bearings
- Widely accepted by classification societies (DNV, ABS, USCG)
Weaknesses
- Hydraulic system adds weight and requires regular oil handling compared with electric PM thrusters
- Fixed‑pitch propeller limits fine thrust control at very low speeds
- Hull penetration creates a permanent opening that must be reinforced in the structure
- Noise and vibration higher than newer permanent‑magnet designs
- Maintenance of shaft seals and bearings is critical; failure can lead to water ingress
Typical Vessels:
Cruise shipsFerriesOffshore supply vessels (OSV)Container ships up to ~200 m LOALNG carriers with bow‑first manoeuvring requirements
Certifications:
DNV class approvalABS classificationUSCG Type Approval
Decision Guide: Choose if you need a high‑thrust, compact bow thruster for vessels that already use hydraulic power and value proven reliability and easy service access. Avoid if emission limits or noise restrictions favour electric permanent‑magnet thrusters, or when space for a larger tunnel is unavailable.
Use Cases: The TT‑750 is typically installed in the bow of large passenger ferries and cruise ships to provide rapid sideways thrust during docking, as well as on offshore supply vessels that require strong low‑speed manoeuvring for DP operations in confined ports. It is also used on container or LNG carriers where a single high‑power bow thruster reduces reliance on tug assistance.
TT-750 stern
· 750.0 kW
· hydraulic tunnel thruster
Power (kW)
750
Thrust (kN)
90.0
Diameter (mm)
1100
Type
tunnel
Location
stern
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- High thrust‑to‑power ratio (90 kN at 750 kW) for rapid bow‑or stern‑side manoeuvring
- Compact 1.1 m tunnel diameter fits vessels with limited hull space
- Proven Kongsberg hydraulic drive system with low vibration and proven service record
- Integrated shaft seal and double‑gear hydraulic arrangement reduces oil leakage risk
Weaknesses
- Fixed‑pitch propeller – no 360° azimuth capability, limiting thrust vectoring flexibility
- Hydraulic power unit adds weight and requires regular fluid inspection/maintenance
- Not rated for ice‑class or extreme Arctic conditions; unsuitable for polar operations
- Installation limited to stern positions where sufficient tunnel height is available
Typical Vessels:
Container shipCruise linerOffshore supply vesselLNG carrierRo‑Ro ferry
Decision Guide: Choose if you need a high‑power, compact stern thruster for dynamic positioning or tight‑harbour manoeuvring on vessels that do not require azimuth thrust or ice‑class capability. Avoid if the ship operates in polar/ice environments, needs full 360° thrust vectoring, or prefers an electric (PM) drive to eliminate hydraulic maintenance.
Use Cases: The TT‑750 is commonly installed on large merchant ships and offshore vessels that require strong lateral thrust for docking, undocking, and DP operations where hull space is at a premium. It is favoured on new builds and retrofits where a reliable, class‑approved hydraulic solution is preferred over more complex azimuth units.
TT-800 bow
· 800.0 kW
· hydraulic tunnel thruster
Power (kW)
800
Thrust (kN)
96.0
Diameter (mm)
1140
Type
tunnel
Location
bow
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- High thrust‑to‑power ratio (96 kN at 800 kW) for rapid bow‑side manoeuvring
- Compact duct diameter (1.14 m) fits into limited hull spaces
- Proven Kongsberg hydraulic control system with built‑in diagnostics
- Standardised mounting and retrofit kits simplify installation on existing ships
- Robust steel construction suitable for routine port operations
Weaknesses
- Fixed‑direction thrust – no 360° azimuth capability
- Hydraulic system requires regular seal and fluid maintenance
- Not certified for ice‑class or extreme Arctic conditions
- Vibration levels can be higher than modern electric PM thrusters
- Limited to bow installation; stern retrofit may need structural modifications
Typical Vessels:
Product tankers (up to 30 kt)Bulk carriers (10‑30 kt)Container ships (5‑8 k TEU)Cruise vesselsOffshore supply & anchor handling tug supply (AHTS) vessels
Decision Guide: Choose if you need a high‑power bow thruster that fits into a relatively small tunnel and the ship already uses hydraulic control systems. Avoid if you require 360° azimuth thrust, ice‑class capability, or want to minimise maintenance by using electric permanent‑magnet units.
Use Cases: The TT‑800 is commonly installed on medium‑size commercial vessels to provide bow‑side thrust for docking, undocking and low‑speed manoeuvring in congested ports. It also supports dynamic positioning assistance on offshore support ships where rapid lateral forces are needed but full DP capability is not required.
TT-800 stern
· 800.0 kW
· hydraulic tunnel thruster
Power (kW)
800
Thrust (kN)
96.0
Diameter (mm)
1140
Type
tunnel
Location
stern
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- High thrust‑to‑power ratio (96 kN @ 800 kW) suitable for vessels up to ~150 m LOA
- Proven Kongsberg design with integrated condition‑monitoring sensors for propeller and hydraulic parameters
- Robust double‑gear hydraulic drive tolerates harsh marine environments
- Standardised 1 140 mm duct diameter fits common hull penetrations without major structural modification
Weaknesses
- Fixed‑direction thrust; no azimuth capability, limiting manoeuvre flexibility compared with azimuth thrusters
- Hydraulic system requires regular oil analysis and filter changes, increasing maintenance workload
- Larger hull opening (≈1.2 m) can affect structural integrity if not properly reinforced
- Lower overall efficiency than newer permanent‑magnet or rim‑drive tunnel units, resulting in higher fuel consumption for DP operations
Typical Vessels:
Container shipBulk carrierCrude oil tankerProduct tankerCruise linerOffshore supply vessel
Certifications:
DNVIMO Type Approval
Decision Guide: Choose the TT‑800 when a reliable, high‑thrust stern thruster is needed for vessels that rely on fixed‑direction thrust for docking or DP support and where hydraulic infrastructure already exists. Avoid it if 360° azimuth capability, lower noise, or maximum energy efficiency (e.g., PM or rim‑drive thrusters) are primary requirements.
Use Cases: The TT‑800 is typically installed in the stern tunnel of large merchant ships to provide low‑speed manoeuvring during port entry/exit, assist dynamic positioning systems on offshore vessels, and improve handling in confined waterways where precise thrust control is essential.
TT-1000 bow
· 1000.0 kW
· Tunnel thruster
Power (kW)
1000
Thrust (kN)
120.0
Diameter (mm)
1300
Type
tunnel
Location
bow
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- Very high power density – 1000 kW in a relatively compact 1300 mm tunnel gives strong bow thrust for large vessels.
- Proven Kongsberg reliability with integrated double‑gear hydraulic drive and standardised maintenance points.
- Available in both constant‑pitch (CP) and fixed‑pitch (FP) propeller options to match vessel control strategies.
- Straight‑through installation simplifies retrofits on existing hulls compared with azimuth units.
- Compatible with Kongsberg’s DP control suite, facilitating seamless integration for dynamic positioning.
Weaknesses
- Large hydraulic power demand; requires robust shipboard hydraulic infrastructure and regular fluid maintenance.
- Thrust is limited to ~120 kN – may be insufficient for the largest ultra‑large crude carriers that favour azimuth thrusters.
- Tunnel geometry restricts installation in vessels with shallow hull sections or limited internal volume.
- Not rated for heavy ice conditions; Arctic operations need the dedicated ARC series instead.
- Fixed thrust direction (no 360° swing) limits manoeuvring flexibility compared with azimuth‑type units.
Typical Vessels:
Very Large Crude Carrier (VLCC)Container ship (>8,000 TEU)Cruise linerOffshore supply vessel with DP2Ro‑Ro passenger ferry
Decision Guide: Choose the TT‑1000 when you need high bow thrust in a compact tunnel layout, have existing hydraulic capacity, and operate in temperate waters where ice capability is not required. Avoid it on vessels that demand full 360° azimuth control, operate regularly in heavy ice, or require thrust levels beyond ~120 kN.
Use Cases: The TT‑1000 is typically installed on large commercial ships to provide precise low‑speed manoeuvring during port entry/exit and to support DP operations on offshore platforms. It is also used on cruise ships for tight docking maneuvers where a powerful, reliable bow thruster is essential.
TT-1000 stern
· 1000.0 kW
· hydraulic tunnel thruster
Power (kW)
1000
Thrust (kN)
120.0
Diameter (mm)
1300
Type
tunnel
Location
stern
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- High power‑to‑size ratio (1000 kW in a 1300 mm tunnel) suitable for medium‑large vessels
- 120 kN thrust gives excellent low‑speed manoeuvring and DP support
- Proven Kongsberg/Rolls‑Royce hydraulic architecture with double‑gear drive and redundant cylinders
- Available in both constant‑pitch (CP) and fixed‑pitch (FP) propeller options for tailored performance
- Standardised mounting simplifies retrofit on existing hulls
Weaknesses
- Requires dedicated high‑capacity hydraulic plant, increasing installation cost and space demand
- Fixed tunnel orientation limits thrust direction to port/starboard only – no 360° swing like azimuth units
- Maintenance intensive: propeller blades, shaft seals and hydraulic system need regular inspection
- Not rated for ice or extreme Arctic conditions (requires the separate ARC family)
- Thrust lower than comparable high‑power azimuth thrusters of similar rating
Typical Vessels:
Container shipCrude oil tankerLNG carrierOffshore supply vesselCruise liner
Decision Guide: Choose if the vessel needs a high‑thrust stern thruster for DP or close‑quarter docking and already has hydraulic capacity; avoid if ice‑class operation, 360° thrust is required, or space constraints prevent a 1.3 m tunnel.
Use Cases: The TT‑1000 is commonly installed on large commercial ships to provide lateral thrust during port entry/exit, dynamic positioning (DP2) maneuvers, emergency stopping, and low‑speed manoeuvring in confined waterways.
TT-1200 bow
· 1200.0 kW
· tunnel thruster
Power (kW)
1200
Thrust (kN)
144.0
Diameter (mm)
1460
Type
tunnel
Location
bow
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- High thrust output (144 kN) relative to power rating, suitable for large vessels
- Compact duct size (1.46 m) fits within moderate hull openings
- Proven Kongsberg hydraulic drive with built‑in redundancy
- Standardized installation interface used on many new builds
- Robust design tolerates fouling and moderate ice conditions
Weaknesses
- Fixed‑direction thrust; no 360° azimuth capability
- Requires hull penetration, increasing structural complexity and potential leakage points
- Hydraulic system demands regular seal and fluid maintenance
- Higher acoustic signature compared with newer electric PM or rim‑drive thrusters
- Weight and space penalties versus integrated azimuth units
Typical Vessels:
Container shipCruise linerOffshore supply vesselLNG carrierRo‑Ro ferry
Decision Guide: Choose if the vessel needs strong, reliable bow thrust for port manoeuvring or DP support and already has hydraulic power‑pack infrastructure. Avoid if a 360° azimuth capability, lower noise footprint, or future‑proof electric propulsion is required.
Use Cases: Installed on new builds and retrofits where high lateral thrust is needed for berthing, unberthing, low‑speed manoeuvring in confined waterways, and as an auxiliary thruster for dynamic positioning systems on medium‑to‑large commercial ships.
TT-1200 stern
· 1200.0 kW
· Fixed‑pitch tunnel thruster
Power (kW)
1200
Thrust (kN)
144.0
Diameter (mm)
1460
Type
tunnel
Location
stern
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- 1.2 MW motor provides strong thrust (144 kN) suitable for large vessels.
- Compact propeller diameter (1460 mm) eases integration in existing hull forms.
- Proven Kongsberg/Rolls‑Royce design with integrated double‑gear hydraulic drive for reliable control.
- Standardised mounting and service interfaces simplify installation and maintenance.
- Compatible with IMO type‑approval and DNV class verification for commercial vessels.
Weaknesses
- Requires a dedicated high‑capacity hydraulic power unit, increasing plant space and weight.
- Fixed‑pitch propeller limits thrust vectoring to the transverse axis only; no 360° swing capability.
- Higher acoustic signature and vibration compared with electric azimuth units.
- Maintenance intensive on propeller blades and shaft seals in harsh marine environments.
- Large power rating may be over‑spec for smaller vessels, impacting fuel efficiency.
Typical Vessels:
Very Large Crude Carrier (VLCC)Ultra‑large Container ShipCruise ShipOffshore Supply VesselLNG Carrier
Certifications:
IMO Type ApprovalDNV GL Class Approval
Decision Guide: Choose if the vessel needs high stern thrust for berthing, un‑dock or dynamic positioning and already has a hydraulic power system compatible with Kongsberg thrusters. Avoid if 360° azimuth capability, lower acoustic emissions, or an all‑electric propulsion architecture are required.
Use Cases: The TT‑1200 is typically installed on the stern of large tankers, container ships and cruise liners to provide rapid transverse thrust during docking, emergency manoeuvres and dynamic positioning support. It is also used on offshore supply vessels where high thrust is needed for station‑keeping in adverse weather.
TT-1500 bow
· 1500.0 kW
· Tunnel thruster
Power (kW)
1500
Thrust (kN)
180.0
Diameter (mm)
1700
Type
tunnel
Location
bow
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- High thrust output (180 kN) in a relatively compact tunnel diameter (1.7 m).
- Proven Kongsberg design with extensive field service data and standardised inspection points.
- Integrated double‑gear hydraulic drive offers reliable power transmission and easy fault isolation.
- Fixed‑pitch propeller delivers consistent thrust direction, simplifying control algorithms for DP or manual operation.
- Standardised bearing and seal modules allow scheduled replacement without major hull work.
Weaknesses
- Fixed azimuth – cannot rotate 360°, limiting manoeuvre flexibility compared with azimuth thrusters.
- Large hull penetration required; installation costs rise on vessels with limited bow space.
- High power demand (1 500 kW) increases auxiliary plant load and fuel consumption.
- Cavitation risk at maximum thrust may reduce efficiency in very shallow water.
- Maintenance‑intensive bearings, seals and propeller blades require regular visual inspection and periodic overhaul.
Typical Vessels:
Container ships (>5 000 TEU)Crude oil or product tankers (30 000–80 000 dwt)LNG carriersOffshore supply vesselsCruise liners
Decision Guide: Choose if the vessel needs a high‑thrust, space‑efficient bow thruster for port entry/exit or DP assistance and can accommodate a fixed‑direction tunnel unit. Avoid if 360° azimuth capability is required, hull space is severely limited, or lower auxiliary power consumption is a priority.
Use Cases: The TT‑1500 is typically installed on large ocean‑going vessels that require strong lateral thrust for tight port manoeuvring, dynamic positioning support during offshore operations, and rapid docking of high‑draft ships where bow thruster effectiveness is critical.
TT-1500 stern
· 1500.0 kW
· tunnel thruster
Power (kW)
1500
Thrust (kN)
180.0
Diameter (mm)
1700
Type
tunnel
Location
stern
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- 1500 kW power delivering 180 kN thrust gives strong berth‑handling capability.
- Large 1.7 m propeller diameter offers high hydraulic efficiency within a compact hull opening.
- Kongsberg double‑gear hydraulic system provides fast response and redundancy.
- Integrated shaft seal design minimises oil leakage risk in harsh marine environments.
- Proven on mega‑fleet vessels (verified_megafleet_2026-06 source).
Weaknesses
- Fixed‑direction thrust; no 360° azimuth capability.
- Requires hull penetration, adding structural complexity and corrosion points.
- High hydraulic power demand may overload existing shipboard systems.
- Maintenance intensive – regular inspection of blades, shaft seals and bearings required.
- Not certified for Arctic ice conditions; unsuitable for Polar Class vessels without the ARC variant.
Typical Vessels:
Container ShipCruise ShipLNG CarrierOil TankerBulk Carrier
Certifications:
IMO Type ApprovalDNV Classification
Decision Guide: Choose if you need high fixed‑direction thrust at the stern of a large vessel and already have hydraulic infrastructure in place. Avoid if you require 360° azimuthing, ice‑class operation, or want to minimise hull penetrations.
Use Cases: Commonly installed on large tankers, container ships and cruise liners for bow‑to‑stern manoeuvring, dynamic positioning assistance on LNG carriers, and as a backup thrust unit during emergency berthing operations.
TT-1800 bow
· 1800.0 kW
· hydraulic tunnel thruster
Power (kW)
1800
Thrust (kN)
216.0
Diameter (mm)
1940
Type
tunnel
Location
bow
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- Very high thrust (216 kN) in a single unit – suitable for VLCCs, ULCCs and large offshore support ships
- Proven Kongsberg/Rolls‑Royce reliability with extensive field service history
- Available in both constant‑pitch (CP) and fixed‑pitch (FP) propeller versions to match vessel control philosophy
- Integrated double‑gear hydraulic drive provides smooth, high‑torque response for DP operations
- Standardised hull penetration dimensions simplify installation on new builds
Weaknesses
- Large tunnel diameter requires significant hull space and structural reinforcement
- Only transverse thrust – no azimuth capability, limiting manoeuvre flexibility compared with azimuth thrusters
- Hydraulic system adds complexity, oil handling requirements and higher maintenance workload
- Not certified for extreme ice conditions; Arctic‑class vessels need the dedicated ARC variant
- Higher vibration levels at full power may require additional acoustic mitigation on passenger ships
Typical Vessels:
Very Large Crude Carrier (VLCC)Ultra Large Crude Carrier (ULCC)Large LNG carrierPanamax/Post‑Panamax container shipOffshore supply vessel (OSV) with DP capability
Certifications:
DNVABS
Decision Guide: Choose if you need >200 kN of bow thrust on a large hull, already have hydraulic power‑pack infrastructure and value Kongsberg’s global support network. Avoid if the vessel operates in ice class conditions, has limited hull space for a 2 m tunnel, or requires full 360° azimuth thrust for advanced DP manoeuvring.
Use Cases: The TT‑1800 is typically installed on deep‑draft tankers and LNG carriers to provide rapid lateral thrust during port entry/exit, emergency stopping, and dynamic positioning while offshore. It is also used on large OSVs that require strong bow pull for station‑keeping near rigs.
TT-1800 stern
· 1800.0 kW
· Tunnel thruster
Power (kW)
1800
Thrust (kN)
216.0
Diameter (mm)
1940
Type
tunnel
Location
stern
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- Very high thrust (216 kN) relative to power (1 800 kW), giving strong manoeuvring capability.
- Large 1.94 m propeller diameter provides good hydraulic efficiency and low cavitation risk.
- Proven Kongsberg design with integrated double‑gear hydraulic pump for reliable control.
- Available in constant‑pitch or fixed‑pitch versions to match vessel propulsion strategy.
- Compact tunnel installation minimizes above‑deck space compared with azimuth units.
Weaknesses
- Requires a sizeable hull opening (≈2 m) which can affect structural integrity and construction cost.
- Fixed thrust direction; no 360° swing like an azimuth thruster, limiting flexibility in tight berths.
- Hydraulic system adds complexity and maintenance workload compared with electric PM thrusters.
- High power demand may increase overall ship energy consumption if used frequently.
- Weight and installation space not published, but typical tunnel units are heavy and may affect stability calculations.
Typical Vessels:
Aframax TankerPanamax Container ShipCruise Vessel (mid‑size)Offshore Supply VesselRo‑Ro Ferry
Decision Guide: Choose if the vessel needs very high stern thrust for docking, dynamic positioning or emergency manoeuvring and already has a hydraulic power system; avoid if hull space is limited, azimuth capability is required, or an all‑electric propulsion concept is preferred.
Use Cases: The TT‑1800 is commonly installed on large commercial ships to provide rapid bow‑to‑stern thrust during port entry/exit, assist in low‑speed manoeuvres under wind or current, and supplement DP systems for fine positioning when the main propeller is at low rpm.
TT-2000 bow
· 2000.0 kW
· Tunnel thruster
Power (kW)
2000
Thrust (kN)
240.0
Diameter (mm)
2100
Type
tunnel
Location
bow
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- Very high thrust‑to‑size ratio (240 kN from a 2.1 m tunnel) suitable for mega‑vessels
- Proven Kongsberg hydraulic drive system with double‑gear pump and robust bearing design
- Integrated monitoring of shaft seal pressure and hydraulic parameters for condition‑based maintenance
- Standardised mounting interface simplifies installation on new builds and retrofits
- Available in both constant‑pitch (CP) and fixed‑pitch (FP) propeller options
Weaknesses
- Large tunnel diameter limits use on vessels with restricted hull space or thin plating
- High hydraulic power demand (≈2 MW) increases overall plant load and fuel consumption
- Maintenance intensive – requires regular inspection of propeller blades, shaft seals and hydraulic fluid
- Weight and structural reinforcement requirements can add to construction cost
- Not optimised for extreme ice conditions; Arctic‑thruster variants are required for polar operations
Typical Vessels:
Post‑Panamax Container ShipVery Large Crude Carrier (VLCC)LNG CarrierCruise ShipOffshore Supply Vessel with DP capability
Certifications:
DNV GL ApprovalABS ClassificationLR (Lloyd’s Register) Approval
Decision Guide: Choose if the vessel needs high bow‑thruster thrust for safe port manoeuvring or dynamic positioning and has sufficient hull space for a 2.1 m tunnel. Avoid on small to medium vessels, ice‑class ships requiring Arctic thrusters, or when hydraulic power availability is limited.
Use Cases: The TT‑2000 is typically installed on mega‑container ships entering congested terminals, VLCCs docking at deep‑water berths, cruise liners performing precise berth alignment, and offshore supply vessels that operate under DP‑2 requirements where rapid lateral thrust is essential.
TT-2000 stern
· 2000.0 kW
· Fixed‑pitch tunnel thruster
Power (kW)
2000
Thrust (kN)
240.0
Diameter (mm)
2100
Type
tunnel
Location
stern
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- Very high thrust (240 kN) suitable for mega‑vessels and DP assistance
- Robust hydraulic drive system with proven Kongsberg reliability
- Large propeller diameter (2100 mm) gives efficient low‑speed thrust
- Standardised installation dimensions for new‑builds and retrofits
- Integrated monitoring of seal pressure and hydraulic parameters
Weaknesses
- Requires substantial hull penetration and internal space
- High power demand (2 MW) increases fuel consumption when used continuously
- Fixed‑pitch design limits thrust vectoring compared with azimuth units
- Maintenance intensive – seals, bearings and hydraulic fluid need regular checks
- Noise and vibration can be higher than rim‑drive or PM thrusters
Typical Vessels:
Very Large Crude Carriers (VLCC)Ultra‑Large Container ShipsLNG carriers (>125 kt)Cruise shipsOffshore supply vessels with DP requirements
Decision Guide: Choose if the vessel needs very high stern thrust for port manoeuvring or as a DP auxiliary on large hulls and already has hydraulic power available. Avoid if space is limited, 360° thrust capability is required, or lower fuel consumption and reduced vibration are higher priorities.
Use Cases: The TT‑2000 is typically installed on the stern of mega‑size tankers, container ships and cruise vessels to provide powerful low‑speed manoeuvring during docking, undocking and emergency bollard‑pull situations. It also serves as an auxiliary thruster in dynamic positioning systems where high thrust reserve is needed.
TT-2200 bow
· 2200.0 kW
· Tunnel thruster
Power (kW)
2200
Thrust (kN)
264.0
Diameter (mm)
2260
Type
tunnel
Location
bow
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- Very high thrust (264 kN) suitable for ultra‑large ships
- Large propeller diameter reduces cavitation and improves efficiency
- Proven Kongsberg hydraulic control system with built‑in diagnostics
- Robust mechanical design rated for continuous operation in harsh sea conditions
- Standardised dimensions simplify integration on new builds
Weaknesses
- Large tunnel size limits installation to vessels with sufficient hull space
- High power demand (2 200 kW) increases fuel consumption and requires substantial hydraulic infrastructure
- Maintenance intensive – propeller blades, seals and bearings require regular inspection
- Fixed‑direction thrust; cannot provide 360° maneuverability like azimuth units
- Weight and structural reinforcement add to overall ship weight budget
Typical Vessels:
VLCC / ULCC crude carriersLarge container ships (>150 m)Cruise linersOffshore supply vesselsLNG carriers
Decision Guide: Choose the TT‑2200 when a vessel needs very high bow thrust for safe docking and low‑speed maneuvering, has sufficient hull volume for a 2.26 m tunnel, and can accommodate the hydraulic power plant. Avoid it on smaller ships, vessels with tight space constraints, or when 360° thrust capability is required (e.g., dynamic positioning using azimuth thrusters).
Use Cases: The TT‑2200 is typically installed as a bow thruster on ultra‑large tankers and container ships to assist in port entry, alongside mooring operations, and on cruise ships for precise berthing. It is also used on offshore supply vessels that require strong lateral thrust while operating near platforms.
TT-2200 stern
· 2200.0 kW
· Tunnel Thruster
Power (kW)
2200
Thrust (kN)
264.0
Diameter (mm)
2260
Type
tunnel
Location
stern
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- Very high thrust output (264 kN) suitable for large vessels and tight port manoeuvring
- Large propeller diameter reduces cavitation and improves efficiency at low speeds
- Integrated double‑gear hydraulic drive offers reliable power transmission and redundancy
- Proven Kongsberg design with extensive field service history and spare‑part support
- Standardised mounting dimensions simplify installation on new builds or retrofits
Weaknesses
- Fixed‑direction thrust; cannot provide 360° azimuth like a pod thruster
- High hydraulic power demand increases auxiliary system load and fuel consumption
- Large duct size limits applicability to vessels with sufficient hull volume at the stern
- Maintenance intensive – regular inspection of propeller blades, shaft seals and hydraulic components required
- Weight and installation complexity are significant; may affect stability calculations
Typical Vessels:
Very Large Crude Carriers (VLCC)Ultra‑Large Container Ships (ULCS)Cruise shipsOffshore supply vesselsRo‑Ro ferries
Decision Guide: Choose if the vessel requires very high lateral thrust for stern manoeuvring, has sufficient hull space for a 2.26 m tunnel and can accommodate the hydraulic power plant. Avoid if azimuthal thrust is required, hull geometry is constrained, or auxiliary power budget is limited.
Use Cases: The TT‑2200 is typically installed on large tankers, container ships and cruise vessels to provide precise low‑speed control during docking, undocking, and close‑quarter manoeuvres in confined ports. It also serves as an auxiliary thrust source for dynamic positioning systems on offshore support ships.
TT-2500 bow
· 2500.0 kW
· hydraulic tunnel thruster
Power (kW)
2500
Thrust (kN)
300.0
Diameter (mm)
2500
Type
tunnel
Location
bow
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- Very high thrust (≈300 kN) in a single unit, enabling rapid bow‑sideways manoeuvres for mega‑vessels
- Proven Kongsberg reliability and extensive global support network
- Available with constant‑pitch or fixed‑pitch propeller blades to match specific performance curves
- Robust double‑gear hydraulic drive reduces wear and extends service intervals
- Compatible with Arctic Thruster (ARC) sealing technology for cold‑water operations
Weaknesses
- Large tunnel diameter reduces hull strength in the bow area and requires significant structural reinforcement
- No 360° azimuth capability – manoeuvring is limited to transverse thrust only
- Higher power consumption compared with electric or permanent‑magnet thrusters of similar thrust
- Installation and retro‑fit are complex, often requiring dry‑dock time and extensive piping work
- Maintenance intensive: regular inspection of propeller blades, shaft seals and hydraulic system required
Typical Vessels:
VLCC / ULCC crude carriersLarge LNG carriers (≥125 k m³)Ultra‑large container ships (>15 000 TEU)Bulk carriers >200 ktOffshore support vessels with high bow‑side thrust requirements
Certifications:
DNV GL Type ApprovalABS Classification
Decision Guide: Choose if: you need very high bow thrust for a vessel ≥150 m length, operate in harsh or icy waters where robust sealing is required, and have the structural allowance for a 2.5 m tunnel. Avoid if: you prefer 360° azimuth manoeuvrability, are limited by hull space or weight, or seek lower power consumption solutions such as permanent‑magnet thrusters.
Use Cases: The TT‑2500 is typically installed on mega‑size tankers and container ships to provide rapid lateral positioning during docking, undocking, and close‑quarter manoeuvres in congested ports. It is also used on LNG carriers for precise alignment with shore facilities and on offshore supply vessels that require strong bow thrust when operating alongside rigs or in ice‑prone regions.
TT-2500 stern
· 2500.0 kW
· hydraulic tunnel thruster
Power (kW)
2500
Thrust (kN)
300.0
Diameter (mm)
2500
Type
tunnel
Location
stern
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- Very high thrust (300 kN) suitable for VLCCs, ULCS and other mega‑vessels
- Proven Kongsberg/Rolls‑Royce hydraulic drive with robust double‑gear system
- Standardised inspection points simplify scheduled maintenance
- Integrated with Kongsberg control & DP packages for seamless operation
Weaknesses
- Large tunnel diameter (2.5 m) reduces usable hull space and may affect structural strength
- Only provides fixed‑direction thrust; no 360° azimuth capability
- High hydraulic power demand (≈2.5 MW) increases fuel consumption and requires dedicated pump capacity
- Installation is limited to stern positions on vessels with sufficient beam
Typical Vessels:
Very Large Crude Carrier (VLCC)Ultra‑Large Container Ship (ULCS)LNG carrierBulk carrier (>200 kt)Offshore support vessel (FPSO, supply ship)
Certifications:
DNV
Decision Guide: Choose if the vessel needs maximum static thrust for low‑speed maneuvering or DP assistance and has sufficient hull volume for a 2.5 m tunnel. Avoid if 360° azimuth thrust is required, hull space is limited, or hydraulic power availability is constrained.
Use Cases: Installed on large tankers and container ships to provide powerful bow‑/stern‑side thrust during port entry, emergency stopping, and dynamic positioning operations where high bollard pull is essential.
TT-3000 bow
· 3000.0 kW
· Hydraulic tunnel thruster
Power (kW)
3000
Thrust (kN)
360.0
Diameter (mm)
2900
Type
tunnel
Location
bow
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- Very high power and thrust (3 MW / 360 kN) suitable for the largest merchant ships
- Large propeller diameter (2.9 m) gives superior hydraulic efficiency compared with smaller tunnel units
- Integrated Kongsberg control system compatible with existing DP and maneuvering consoles
- Proven reliability on mega‑fleet installations, with extensive field service support
- Standardised hydraulic interface simplifies retro‑fit on vessels already equipped with high‑capacity hydraulic systems
Weaknesses
- Large hull penetration (≈3 m) limits installation to ships with sufficient bow space and structural reinforcement
- High hydraulic power demand requires robust pumps and larger fluid reservoirs, increasing plant weight and complexity
- Maintenance intensive – seals, O‑rings and bearing play must be inspected at 5‑year intervals
- Fixed‑direction thrust (no azimuth) reduces flexibility compared with 360° azimuth thrusters in tight berths
- Higher initial cost and longer lead time than smaller standard tunnel units
Typical Vessels:
Very Large Crude Carriers (VLCC)Ultra‑Large Container Vessels (ULCV)LNG carriers (>125 ktons)Cruise shipsOffshore supply vessels and platform support ships
Certifications:
DNVABSLloyd's Register
Decision Guide: Choose if the vessel requires maximum bow thrust for safe maneuvering in confined ports, has existing high‑capacity hydraulic infrastructure, or operates under dynamic positioning where extra lateral force improves station keeping. Avoid if hull space is limited, a 360° azimuth capability is essential, or the ship’s power plant cannot support the required hydraulic load.
Use Cases: The TT‑3000 is typically installed on mega‑size tankers and container ships to assist in low‑speed docking, emergency stopping, and DP‑assisted station keeping. It is also used on cruise liners for precise berth alignment and on offshore vessels that need strong lateral thrust for dynamic positioning near rigs or platforms.
TT-3000 stern
· 3000.0 kW
· high‑power tunnel thruster
Power (kW)
3000
Thrust (kN)
360.0
Diameter (mm)
2900
Type
tunnel
Location
stern
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- Very high thrust (360 kN) suitable for the largest tankers, cruise ships and DP‑operated vessels
- Robust hydraulic drive with double‑gear system offering reliable control under heavy loads
- Large tunnel diameter reduces cavitation risk and improves efficiency at high power levels
- Integrated monitoring of shaft seal pressure and hydraulic parameters for condition‑based maintenance
- Available in both constant‑pitch (CP) and fixed‑pitch (FP) propeller options to match vessel DP strategy
Weaknesses
- Large physical envelope requires significant hull penetration and structural reinforcement
- Higher installation and lifecycle cost compared with lower‑power tunnel thrusters or azimuth units of similar rating
- Hydraulic system complexity increases maintenance workload and spare‑parts inventory
- Limited retrofit suitability for vessels with restricted stern space or low‑draft constraints
- Noise and vibration levels can be higher than comparable rim‑drive or permanent‑magnet designs
Typical Vessels:
Very Large Crude Carrier (VLCC)Ultra‑Large Container Ship (ULCS)Cruise ship (>150 000 GT)Offshore supply vessel with DP2/DP3LNG carrier (large class)
Certifications:
DNV
Decision Guide: Choose if the vessel requires maximum stern thrust for safe berthing, dynamic positioning or emergency maneuvering on ships >150 000 GT where hull space permits a large tunnel. Avoid if the ship has limited stern volume, tight budget constraints, or if an azimuth or rim‑drive thruster can meet the required thrust with lower installation complexity.
Use Cases: The TT‑3000 is typically installed on new builds of ultra‑large tankers, cruise liners and DP‑capable offshore vessels to provide reliable low‑speed control during port entry, emergency stop‑and‑go maneuvers, and precise station‑keeping in offshore operations. It is also used as a retrofit on existing large ships that need upgraded maneuverability for stricter port regulations.
TT-3500 bow
· 3500.0 kW
· Tunnel thruster
Power (kW)
3500
Thrust (kN)
420.0
Diameter (mm)
3300
Type
tunnel
Location
bow
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- Very high thrust (420 kN) suitable for mega‑vessels and DP assistance
- Large propeller diameter reduces cavitation and improves efficiency at high power
- Proven Kongsberg hydraulic drive with robust control integration
- Modular installation – can be fitted as a fixed or retractable unit
- Extensive service network and documented maintenance procedures
Weaknesses
- Large tunnel size (3.3 m) limits applicability on vessels with restricted hull space
- High hydraulic power demand; requires sizable pumps and reservoirs
- Higher fuel consumption compared with newer electric or permanent‑magnet thrusters
- Maintenance intensive – propeller blades, shaft seals and bearings need regular inspection
- Weight and installation complexity increase dry‑dock time
Typical Vessels:
Very Large Crude Carrier (VLCC)Ultra‑Large Container Ship (ULCS)LNG carrierCruise shipOffshore supply vesselHeavy lift / RoRo vessel
Certifications:
IMO Type ApprovalDNV GL class approval
Decision Guide: Choose if the vessel requires very high bow thrust for safe docking or dynamic positioning, has sufficient hydraulic power capacity and enough hull volume to accommodate a 3.3 m tunnel. Avoid on smaller ships, vessels with tight hull constraints, or when energy efficiency and low emissions are primary drivers – in those cases an electric or permanent‑magnet thruster may be preferable.
Use Cases: The TT‑3500 is typically installed on large tankers, container ships and cruise liners to provide powerful bow thrust for port entry/exit, tight berth handling, emergency bollard‑pull maneuvers and as a supplemental DP actuator in harsh weather conditions.
TT-3500 stern
· 3500.0 kW
· Electric tunnel thruster
Power (kW)
3500
Thrust (kN)
420.0
Diameter (mm)
3300
Type
tunnel
Location
stern
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- Very high thrust (420 kN) suitable for large ships and dynamic positioning
- Robust Kongsberg design with proven reliability in harsh conditions
- Large propeller diameter (3.3 m) gives good hydraulic efficiency at low speeds
- Integrated hydraulic control system simplifies installation and operation
- Standardised hull opening reduces custom engineering work
Weaknesses
- Large tunnel diameter requires significant hull penetration and structural reinforcement
- Higher power consumption (3 500 kW) increases fuel‑related operating costs
- Only provides thrust in a fixed direction; no 360° azimuth capability
- Hydraulic components add maintenance complexity compared with fully electric azimuth units
- Weight and space requirements may limit suitability for smaller vessels
Typical Vessels:
VLCC / ULCC crude carriersLNG carriers (large class)Ultra‑large container ships (>10 000 TEU)Cruise shipsOffshore support and supply vessels with DP requirements
Certifications:
IMO Type ApprovalDNV GL Class approval
Decision Guide: Choose if you need very high stern thrust for a large vessel, require proven reliability and standardised installation, and have sufficient hull space for a 3.3 m tunnel. Avoid if you need full 360° maneuverability, have limited hull opening size, or prefer lower‑power electric azimuth solutions.
Use Cases: The TT‑3500 is typically installed on mega‑size tankers, LNG carriers and large cruise ships to provide powerful low‑speed thrust for berthing, unberthing, dynamic positioning in confined ports, and emergency stop manoeuvres. It is also used on offshore vessels that require strong stern thrust for station‑keeping during DP operations.
TT-4000 bow
· 4000.0 kW
· Tunnel thruster
Power (kW)
4000
Thrust (kN)
480.0
Diameter (mm)
3700
Type
tunnel
Location
bow
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- Very high thrust (480 kN) enables rapid berthing and unberthing of mega‑vessels
- Large 3.7 m propeller diameter reduces cavitation and improves efficiency at full power
- Integrated hydraulic drive with Kongsberg control system allows fine thrust modulation and DP support
- Proven Kongsberg/Rolls‑Royce reliability and extensive class approvals
- Modular design simplifies installation in new builds and major retrofits
Weaknesses
- Large hull penetration (≈3.7 m) requires substantial structural reinforcement
- High power demand (4 MW) increases ship’s overall energy consumption
- Heavy unit mass and associated hydraulic equipment add significant weight aloft
- Maintenance complexity – frequent inspection of propeller blades, shaft seals and hydraulic system
- Limited suitability for small or medium‑size vessels where space and power are constrained
Typical Vessels:
VLCC / ULCC crude carriersUltra‑large container ships (ULCS)LNG carriers (Q‑Fit, Q‑Max)Large cruise linersOffshore supply & construction vessels with DP capability
Certifications:
DNV GL class approvalABS class approvalIMO Type Approval
Decision Guide: Choose if the vessel requires very high bow thrust for tight port manoeuvring, dynamic positioning or ice‑class operations and has sufficient hull space and power generation capacity. Avoid on smaller ships, vessels with limited hydraulic power budgets, or where installation envelope cannot accommodate a 3.7 m tunnel.
Use Cases: The TT‑4000 is typically installed on mega‑size tankers, container ships and cruise vessels to provide rapid lateral thrust for berthing in congested terminals, to support DP operations during offshore work, and to assist emergency stop manoeuvres where conventional rudders are insufficient.
TT-4000 stern
· 4000.0 kW
· hydraulic tunnel thruster
Power (kW)
4000
Thrust (kN)
480.0
Diameter (mm)
3700
Type
tunnel
Location
stern
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- Very high static thrust (480 kN) suitable for mega‑size tankers and cruise ships
- Robust hydraulic drive with Kongsberg’s proven diagnostics and condition monitoring
- Large tunnel diameter provides efficient water flow and lower cavitation risk
- Standardised installation – fits existing hull openings designed for TT series units
- Class‑approved and widely supported by Kongsberg service network
Weaknesses
- Fixed‑direction thrust; no 360° azimuth capability, limiting maneuvering flexibility
- Significant hull penetration required (3.7 m tunnel) which may affect structural integrity and internal layout
- Higher hydraulic power consumption compared with electric or azimuth thrusters for the same manoeuvre
- Maintenance intensive – requires regular inspection of propeller blades, shaft seals and hydraulic system
- Weight and space requirements restrict use on smaller vessels
Typical Vessels:
VLCC / ULCC crude oil tankersLNG carriers (Q‑Fit, Q‑Max)Large cruise shipsOffshore supply & anchor handling tug supply vessels (AHTS)Very large container ships (>10 000 TEU)
Certifications:
DNV GL class approvalABS class approvalLloyd's Register approval
Decision Guide: Choose the TT‑4000 when a vessel needs maximum static thrust for safe docking, undocking or DP support and has sufficient hull space for a 3.7 m tunnel; avoid it on ships that require full azimuth maneuverability, have limited beam/hold space, or where lower power electric thrusters are more economical.
Use Cases: Installed in the stern of mega‑tankers and cruise liners to provide powerful low‑speed thrust for port entry, emergency bollard pull, and as a primary DP‑2/DP‑3 maneuvering aid; also used on offshore supply vessels to assist with precise station‑keeping during offshore operations.
TT-4500 bow
· 4500.0 kW
· Tunnel thruster
Power (kW)
4500
Thrust (kN)
540.0
Diameter (mm)
4100
Type
tunnel
Location
bow
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- Very high thrust (540 kN) enables rapid bow‑side maneuvering of mega‑size ships.
- Integrated with Kongsberg DP control systems for seamless dynamic positioning support.
- Robust double‑gear hydraulic drive and proven Kongsberg bearing design reduce downtime.
- Large propeller diameter provides good low‑speed efficiency compared to smaller units.
Weaknesses
- Large tunnel size (4.1 m) limits installation to vessels with sufficient hull volume.
- High power demand (4.5 MW) increases fuel consumption and requires a sizable hydraulic power unit.
- Tunnel thrusters lack 360° azimuth capability, limiting manoeuvre flexibility in tight berths.
- Maintenance of the large propeller and shaft seals can be labour‑intensive.
Typical Vessels:
VLCCULCCUltra‑large container shipLarge LNG carrierCruise ship (≥200 m)Offshore support vessel with DP2/DP3
Certifications:
DNVABS
Decision Guide: Choose if the vessel requires very high bow thrust for safe docking or DP operation and already uses Kongsberg control architecture. Avoid if hull space is limited, a 360° azimuth thruster is preferred, or power consumption must be minimised.
Use Cases: Installed in a dedicated bow tunnel on mega‑size tankers and container ships to provide rapid lateral thrust during docking, undocking, and dynamic positioning maneuvers; also used as an emergency stop thruster on vessels with high manoeuvring demands.
TT-4500 stern
· 4500.0 kW
· High‑power tunnel thruster
Power (kW)
4500
Thrust (kN)
540.0
Diameter (mm)
4100
Type
tunnel
Location
stern
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- Very high thrust (540 kN) enables rapid stern‑side manoeuvring of mega‑ships.
- Large propeller diameter reduces cavitation and improves efficiency at full power.
- Proven Kongsberg hydraulic drive system with built‑in redundancy for DP operations.
- Compact stern installation compared with azimuth units of similar thrust, saving deck space.
- Standardised hull penetration and mounting kits simplify integration on new builds.
Weaknesses
- Power demand of 4 500 kW requires substantial electrical/hydraulic plant capacity.
- Large tunnel diameter necessitates significant structural reinforcement of the stern.
- Hydraulic seals and propeller blades are maintenance‑intensive, especially in harsh environments.
- Limited steering angle (typically ±30°) compared with full‑rotation azimuth thrusters.
- Weight and space requirements may preclude installation on smaller vessels.
Typical Vessels:
ULCC / VLCC tankerLarge LNG carrierUltra‑large container ship (>15 000 TEU)Cruise ship (≥200 m length)Offshore support vessel with DP2 requirement
Certifications:
DNV GL class approvalABS classificationIMO Type Approval for thrusters (Resolution MSC.428(98))
Decision Guide: Choose if the ship requires very high stern thrust for safe docking or dynamic positioning of vessels >150 000 gt and has sufficient hull space and power plant capacity. Avoid on smaller ships, on projects where low‑power consumption or full 360° steering is a priority, or when an electric azimuth thruster offers better integration with existing propulsion architecture.
Use Cases: The TT‑4500 is typically installed on mega‑tankers and large container vessels to provide rapid stern‑side thrust during port entry/exit, assist DP2 stations in offshore operations, and give additional manoeuvring reserve for ice‑class or high‑wind conditions. It is also used on cruise ships where a powerful stern thruster complements bow thrusters for tight berthing.
TT-5000 bow
· 5000.0 kW
· hydraulic tunnel thruster
Power (kW)
5000
Thrust (kN)
600.0
Diameter (mm)
4500
Type
tunnel
Location
bow
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- Very high thrust (≈600 kN) enables rapid lateral manoeuvring of mega‑vessels.
- Robust hydraulic drive with double‑gear system provides reliable power transmission.
- Large tunnel diameter reduces cavitation and improves efficiency at high thrust levels.
- Proven Kongsberg/Rolls‑Royce design with extensive field service history.
Weaknesses
- Large physical envelope (4.5 m tunnel) limits installation to vessels with sufficient hull volume.
- High hydraulic power demand increases auxiliary plant load and fuel consumption.
- Maintenance complexity – requires regular inspection of propeller blades, shaft seals and hydraulic system.
- Weight and structural reinforcement requirements add to construction cost.
Typical Vessels:
VLCC / ULCCLNG carrier (large LNG carriers)Cruise shipOffshore supply vessel (OSV) – heavy liftBulk carrier (>200 kt)
Certifications:
IMO Type Approval (D‑2)
Decision Guide: Choose if the vessel needs very high bow thrust for DP or tight‑port manoeuvring and has sufficient hull space for a 4.5 m tunnel. Avoid on smaller ships, where the size, weight and hydraulic power requirements outweigh the maneuvering benefit.
Use Cases: Installed on ultra‑large crude carriers, large LNG carriers and cruise liners to provide rapid side thrust during docking, undocking and dynamic positioning in confined waterways; also used on heavy‑lift offshore vessels that require strong bow control for cargo handling operations.
TT-5000 stern
· 5000.0 kW
· high‑power tunnel thruster
Power (kW)
5000
Thrust (kN)
600.0
Diameter (mm)
4500
Type
tunnel
Location
stern
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Strengths
- Very high static thrust (≈600 kN) suitable for VLCCs and ultra‑large container ships
- Large propeller diameter provides good hydraulic efficiency and reduced cavitation
- Proven Kongsberg/Rolls‑Royce design with integrated double‑gear hydraulic drive and robust sealing system
- Compatible with DP2/DP3 dynamic positioning systems
- Standard class approvals (IMO Type Approval, DNV) simplify certification
Weaknesses
- Large hull penetration required; limits installation on vessels with restricted stern space
- Higher power consumption (5 MW) increases fuel use and auxiliary load
- Tunnel configuration offers only axial thrust – no 360° vectoring like azimuth units
- Hydraulic system adds maintenance complexity and potential leak points
- Weight and size may affect payload calculations on marginal vessels
Typical Vessels:
VLCCULCS (Ultra‑Large Container Ship)Very Large Bulk CarrierLNG carrierOffshore support vessel with DP requirements
Certifications:
IMO Type ApprovalDNV Class approval
Decision Guide: Choose if the vessel needs very high axial thrust for safe berthing, un‑loading or emergency bollard‑pull and has sufficient stern space for a large tunnel unit. Avoid if 360° thrust vectoring is required, hull penetration must be minimized, or power efficiency is a primary concern compared with azimuth thrusters.
Use Cases: The TT‑5000 is typically installed on the stern of ultra‑large tankers and container ships to provide powerful low‑speed maneuverability during docking, undocking, and emergency stop scenarios. It also serves as a supplemental thrust source for DP2/DP3 offshore vessels operating in confined ports or high‑current areas.
Kamewa TT Series
500-4000 kW
· 2500.0 kW
· Seawater
· Electric tunnel thruster
Power (kW)
2500
Type
Tunnel Thruster Electric
Technical Specifications
- Tunnelthrusters
- Output 200–3,700 kW, propeller diameter 1,600–2,000 mm, thrust up to 229 kN, available in CP (Constant Pitch) and FP (Fixed Pitch)
- Azimuth-thrusters
- Leistung 330-6.500 kW (mechanical/hybrid), neun Baumgroessen, Zugkraft optimiert fuer Bollard-Pull, 360°-Schwenkung
- Arctic Thruster (ARC)
- Power from 3 MW to >10 MW, no oil-sea interfaces, adaptive seals, Polar-Class-2 and Icebreaker-7 to 9 MW
- Permanent Magnet (PM) Thrusters
- TT-PM 1000 kW (146 kN), TT-PM 1600 kW (229 kN), Effizienzsteigerung 7-13% gegenueber Diesel-Elektrik
- Hydraulik-standard
- Double gear hydraulics for control/ventilation/lubricant, double cylinder with pressure pipe safety, seal tank with refueling capacity
- Lagerung
- Rollenlager fuer Schubwelle, Schmierung mit Fett, Dichtung an Lagergehausen, Toleranz-Freispiele typisch 0,5-2,0 mm
Product Lines
- US Azimuth Thruster
- Arctic Thruster (ARC)
- TCNS/C Azimuth Thruster (Swing-up/Retractable)
- Rim Drive Azimuth Thruster (RD-AZ)
- Tunnel Thruster Type TT/TTH
- Permanent Magnet Tunnel Thruster (TT-PM)
- Rim Drive Tunnel Thruster (RD-TT)
- Underwater Mountable Azimuth Thruster (UUC/UUC-PM)
- Retractable Azimuth Thruster (UL/ULE)
- Azipull Thruster (Integrated PM Motor)
Common Failures & Inspection Points
- Area: Propellerblaetter: Verschleiss, Risse, Verformung, SeewuchsbewuchsCheck: Sichtpruefung auf Schaedigungen, Freispiel, Blattoberflaeche glatt ohne Kratzer/Dellen. Blattwurzel-O-Ringe auf Verschleiss checken, Spitzzenspiel messen. Bei Zweifeln: 1,5 bar Luftdruck auf VT-Nippel, Seifenblasen-Test auf Oellecks.
- Area: Propellerwellen-Dichtung: Durchfeuchtuung, Oelaustrittsverlust, VerschleissCheck: Visual inspection for leaks around shaft seal, check sealing cavity (monitored automatically via ARC). Observe seal clip pressure (e.g. via sensor output). At 5-year overhaul: renew seal. Check adaptive pressure regulation.
- Area: Lagerfreispiel/Lagerverschleiss: Axiales/Radiales Play ueber Norm, BohrlochabtragCheck: Calipers/counter gauges: measure shaft diameter and bores (target value via manufacturer data sheet). Document caliper readings. If exceeded: replace bearing journal/bearing shells. Observe vibration/noise during operation.
- Area: Hydraulikfluid: Verschmutzung, Feuchtigkeit, Alterung, Farb-/GeruechsveraenderungCheck: Check fluid level in tank (target level). Color test: light/yellowish OK, cloudy/dark = change required. Particle count (if available). Change filter per manufacturer interval. Perform pressure test on hydraulic line.
- Area: Hydraulik-Leitungen/Verbindungen: Risse, Lecks, Verformung, korrosive BelaegeCheck: Visual inspection of all hoses, pipes, connections for defects. Check for dryness, corrosion (rust spots), kink marks. High-frequency leak test if necessary. Observe operating pressure during voyage.
- Area: Elastomer-Bauteile (O-Ringe, Dichtlippen, Gummistuecke): Hartung, Risse, QuellungserscheinungenCheck: Visual inspection of all O-rings/seals for wear, hardening, deformation. Test with finger pressure (elasticity). Clean O-ring grooves/lubricate with gearbox oil (at 5-year overhaul). Replace damaged parts.
Type-universal inspection/service points for bow/stern thrusters (Kongsberg, Mega-Swarm 2026-06). Per-model specs not auto-populated.
Service: Kamewa TT series. VFD enables soft start and speed control. Annual gear oil change. Propeller inspection at drydock.
Spare Parts: Rolls-Royce (Kongsberg): gearbox oil and seals on board. Lead time: 3-6 weeks.
Strengths
- High power rating (up to 2 500 kW) delivering up to ~229 kN thrust in a compact tunnel layout
- Integrated variable frequency drive enables soft start, fine speed regulation and energy‑efficient operation
- Available with constant‑pitch or fixed‑pitch propellers for optimisation of bollard‑pull performance
- Robust double‑gear hydraulic control system and roll‑bearing shaft design reduce wear and extend service intervals
- Proven class‑approved design widely installed on DP‑equipped tankers, container ships and offshore vessels
Weaknesses
- Tunnel geometry occupies significant hull volume; not suitable for vessels with limited beam or shallow draft
- Thrust is fixed in a single direction – no 360° azimuth capability, limiting manoeuvre flexibility compared with azimuth thrusters
- High‑power electric drive and hydraulic control increase initial cost and require specialised maintenance (seal, bearing, propeller inspections)
- Potential for cavitation at very high thrust settings, especially on low‑speed vessels
- Maintenance of shaft seals and roll bearings is critical; failure can lead to costly dry‑dock repairs
Typical Vessels:
Crude oil tankerProduct tankerContainer ship (≥8 000 TEU)Bulk carrier (≥150 000 dwt)LNG/LPG carrierOffshore supply vesselCruise ship
Certifications:
DNV GL Type Approval
Decision Guide: Choose if: you need high static thrust for low‑speed manoeuvring or DP support, have sufficient hull space for a tunnel installation, and prefer an electric drive with proven reliability. Avoid if: vessel geometry limits tunnel size, you require full 360° thrust vectoring, or budget constraints favour lower‑cost azimuth units.
Use Cases: The TT series is typically installed on large tankers and container ships to provide bow‑ and stern‑thruster assistance during docking, undocking and low‑speed manoeuvres. It is also used as a DP‑auxiliary thruster on offshore supply vessels and cruise ships where high bollard pull and precise speed control are required.
Caterpillar / MaK
44
CMP-TT-50 bow
unverified
· 50.0 kW
· tunnel thruster
Power (kW)
50
Thrust (kN)
6.0
Diameter (mm)
540
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (6 kN at only 50 kW).
- Compact 540 mm tunnel fits in vessels with limited bow space.
- Caterpillar brand provides worldwide service support and parts availability.
- Low acoustic signature compared with larger azimuth units, beneficial for noise‑sensitive operations.
- Simple fixed‑direction installation reduces control system complexity.
Weaknesses
- Maximum thrust of 6 kN may be inadequate for large tankers or high‑power tugs.
- Tunnel geometry can induce hull stress and requires proper reinforcement during installation.
- Fixed‑direction design lacks the vectoring flexibility of azimuth thrusters.
- Seals and water‑lubricated bearings demand regular inspection in harsh marine environments.
- Power rating limited to 50 kW; not suitable where higher power margins are required.
Typical Vessels:
Offshore supply vesselCoastal cargo shipSmall passenger ferryResearch / survey vesselWorkboat
Decision Guide: Choose if you need a reliable, compact bow thruster for vessels up to ~2 000 GT with limited power budget and require low noise during docking or station‑keeping. Avoid if the vessel demands thrust above 8–10 kN, azimuth capability, or operates in high‑power maneuvering scenarios such as large tankers or high‑speed tugs.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CMP-TT-50 stern
unverified
· 50.0 kW
· tunnel thruster
Power (kW)
50
Thrust (kN)
6.0
Diameter (mm)
540
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Compact 540 mm diameter fits into limited hull space at the stern
- Good thrust‑to‑power ratio (6 kN from 50 kW) for vessels up to ~5,000 GT
- Robust Cat Marine design with proven service life in harsh marine environments
- Straight‑forward installation and integration with existing control systems
- Low acoustic signature compared with larger azimuth thrusters
Weaknesses
- Maximum thrust of 6 kN may be insufficient for larger ships or heavy‑weather maneuvering
- Higher power consumption relative to some high‑efficiency electric thrusters
- Limited ice‑class certification (if required) and not suited for polar operations
- Spare‑parts logistics tied to Cat Marine network, which can affect lead times in remote ports
- Fixed tunnel orientation offers less directional flexibility than azimuth units
Typical Vessels:
Offshore Supply VesselCoastal FerryWorkboat / Utility vesselFeeder Container Ship (up to ~5,000 GT)Small Cruise or Passenger ship
Decision Guide: Choose if: you need a compact, reliable stern thruster for vessels up to about 5,000 GT with moderate maneuvering requirements and prefer Cat Marine after‑sales support. Avoid if: the vessel demands higher thrust (>10 kN), ice‑class operation, or a fully steerable azimuth solution.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CMP-TT-75 bow
unverified
· 75.0 kW
· tunnel thruster
Power (kW)
75
Thrust (kN)
9.0
Diameter (mm)
560
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (≈9 kN from 75 kW) for its size
- Compact 560 mm tunnel diameter fits tight hull spaces
- Robust, low‑maintenance design typical of Cat Marine Power units
- Integrated with standard marine control systems and optional variable‑frequency drive
- IMO D‑2 compliance (marine equipment safety standard)
Weaknesses
- Limited maximum thrust compared with larger azimuth or pod thrusters (>10 kN)
- Fixed direction; cannot provide 360° thrust vectoring
- Performance drops in very shallow water due to tunnel suction effects
- May require hull reinforcement at installation point
Typical Vessels:
Bulk Carrier (Handymax/Handysize)Container Ship (Feeder class)Offshore Supply VesselFerryCoastal Cargo Vessel
Certifications:
IMO D-2
Decision Guide: Choose if: you need a cost‑effective, compact bow thruster delivering up to 9 kN for vessels under 30 000 gt operating in moderate sea states and confined ports. Avoid if: the vessel requires high thrust (>10 kN), full 360° maneuverability, or operates frequently in very shallow water where tunnel suction is a concern.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CMP-TT-75 stern
unverified
· 75.0 kW
· tunnel thruster
Power (kW)
75
Thrust (kN)
9.0
Diameter (mm)
560
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Compact 560 mm diameter fits in limited hull spaces
- High thrust‑to‑power ratio (≈9 kN @ 75 kW) for its size class
- Proven Cat Marine reliability with low vibration and noise levels
- Straightforward installation at the stern with standard mounting brackets
- Integrated cooling and sealed bearing design reduces routine maintenance
Weaknesses
- Maximum thrust of 9 kN may be insufficient for larger vessels or high‑wind conditions
- Tunnel geometry can cause cavitation if operated near full power continuously
- Less maneuverability than azimuth (azipod) units, especially for tight turning circles
- Maintenance access requires removal of the duct cover, which can be time‑consuming on cramped decks
- Limited to vessels with sufficient hull thickness to accommodate the tunnel aperture
Typical Vessels:
Offshore supply vessel (OSV)Crew transfer vessel (CTV)Ferry / passenger craftWorkboat / utility vesselSmall container feeder or coastal trader
Decision Guide: Choose if the vessel needs a cost‑effective, compact stern thruster for moderate thrust requirements and has adequate hull thickness for a tunnel installation. Avoid on large tankers, cruise ships, or vessels that demand high‑power azimuth propulsion for extreme maneuverability.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CMP-TT-100 bow
unverified
· 100.0 kW
· tunnel thruster
Power (kW)
100
Thrust (kN)
12.0
Diameter (mm)
580
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (12 kN at 100 kW) for its size class
- Compact bow installation – 580 mm duct fits in moderate hull openings
- Integrated, marine‑grade control electronics supplied by Cat Marine Power
- Proven brand reputation for reliability and service support
Weaknesses
- Maximum thrust may be insufficient for large vessels or high wind/current conditions
- Duct diameter can affect hull form resistance when the thruster is not in use
- Requires regular bearing lubrication and periodic duct cleaning to maintain performance
- Noise and vibration levels are typical of conventional tunnel designs, not low‑noise variants
Typical Vessels:
Offshore Supply VesselContainer Ship (up to ~150 m LOA)Cruise FerryGeneral Cargo / Bulk Carrier (mid‑size)Coastal Patrol or Research vessel
Decision Guide: Choose the CMP‑TT‑100 when a moderate 12 kN bow thrust is needed, hull space for a 580 mm tunnel is available, and you prefer Cat Marine Power’s after‑sales support. Avoid it on very large vessels, high‑speed ships, or where higher thrust (>15 kN) or ultra‑low noise is mandatory.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CMP-TT-100 stern
unverified
· 100.0 kW
· tunnel thruster
Power (kW)
100
Thrust (kN)
12.0
Diameter (mm)
580
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (12 kN at only 100 kW).
- Compact 580 mm diameter duct fits in limited stern spaces.
- Robust stainless‑steel construction rated for harsh marine environments.
- Integrated low‑noise, low‑vibration motor and control electronics.
- Cat Marine Power’s global service network simplifies maintenance.
Weaknesses
- Maximum thrust (12 kN) may be insufficient for larger vessels or high‑wind conditions.
- Installation requires a dedicated cooling water circuit and sufficient stern clearance.
- Power demand of 100 kW can strain smaller ship electrical systems if not properly sized.
- Spare parts specific to Cat Marine models may have longer lead times in remote ports.
Typical Vessels:
Medium‑size tankers (up to ~30,000 DWT)Container ships (up to ~10,000 TEU)Offshore supply vesselsCruise ferriesLNG carriers (small to medium)
Decision Guide: Choose if: you need a reliable 12 kN stern thruster for vessels up to ~30,000 DWT, have adequate stern space for a 580 mm duct, and value Cat Marine’s service support. Avoid if: the vessel requires higher thrust (>15 kN), has severe space constraints, or the ship’s power plant cannot accommodate an additional 100 kW load.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CMP-TT-150 bow
unverified
· 150.0 kW
· tunnel thruster
Power (kW)
150
Thrust (kN)
18.0
Diameter (mm)
620
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (≈0.12 kN/kW) for its size
- Caterpillar’s proven reliability and global service network
- Compact duct design fits most bow sections up to 620 mm diameter
- Low vibration and noise thanks to balanced impeller and optimized tunnel geometry
- Integrated monitoring compatible with Caterpillar PowerTech control systems
Weaknesses
- Diameter (620 mm) may be too large for narrow hulls or retrofits
- Fixed‑pitch design limits fine thrust modulation compared with azimuth units
- Maximum thrust of 18 kN may be insufficient for very large vessels or high‑wind conditions
- Higher power consumption than smaller thrusters when operating at low load
Typical Vessels:
Container feederRo‑Ro ferryOffshore supply vesselCruise ship (mid‑size)LNG carrier (small to medium)
Certifications:
ABSDNV GL
Decision Guide: Choose if you need a dependable 150 kW bow thruster with solid thrust for vessels up to ~200 m LOA, have sufficient bow space for a 620 mm tunnel, and value Caterpillar’s service support. Avoid if the vessel requires higher thrust (>20 kN), has very tight hull constraints, or prefers azimuth/azipod maneuvering solutions.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CMP-TT-150 stern
unverified
· 150.0 kW
· tunnel thruster
Power (kW)
150
Thrust (kN)
18.0
Diameter (mm)
620
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (18 kN at 150 kW) provides strong lateral force for tight port operations.
- Robust tunnel geometry reduces cavitation and extends service life in abrasive water conditions.
- Standardized stern mounting kit simplifies installation on new builds or retrofits.
- Caterpillar’s global dealer network offers rapid spare‑parts supply and field support.
- Integrated control interface compatible with most ship bridge consoles.
Weaknesses
- Relatively large tunnel diameter (620 mm) may limit fit in vessels with restricted hull space.
- Power demand of 150 kW can strain limited auxiliary generators on smaller ships.
- Noise and vibration levels are higher than low‑speed propeller‑type thrusters, requiring additional acoustic mitigation.
- Weight and detailed dimensions are not publicly disclosed, complicating early‑stage weight‑budget calculations.
Typical Vessels:
Container ships (up to 5 000 gt)Handymax / Supramax bulk carriersRo‑Ro ferriesOffshore supply vesselsCruise ship tenders
Decision Guide: Choose if the vessel requires strong stern thrust for docking, dynamic positioning backup, or maneuvering in confined ports and you value Caterpillar’s service network. Avoid if hull space cannot accommodate a 620 mm tunnel, auxiliary power is limited, or acoustic noise must be minimized.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CMP-TT-200 bow
unverified
· 200.0 kW
· tunnel thruster
Power (kW)
200
Thrust (kN)
24.0
Diameter (mm)
660
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (24 kN at 200 kW)
- Compact 660 mm tunnel fits medium‑size vessels with limited hull space
- Robust Caterpillar Marine Power construction and proven reliability
- Integrated control electronics compatible with most bridge systems
- Relatively low acoustic signature compared with larger azimuth units
Weaknesses
- Requires hull penetration and structural reinforcement during installation
- Tunnel geometry can cause increased hull vibration and potential fouling
- Limited to bow‑only thrust vectoring; no 360° rotation like azimuth pods
- Maximum thrust may be insufficient for very large vessels or high‑wind conditions
- Higher power consumption than smaller auxiliary thrusters
Typical Vessels:
Handymax bulk carrierProduct tanker (up to ~30,000 dwt)Offshore supply vesselCruise ship (mid‑size)Container feeder
Decision Guide: Choose if you need a reliable, cost‑effective bow thruster for vessels up to about 150 m LOA where hull space is limited and dynamic positioning assistance is required. Avoid if the vessel demands higher thrust levels (>30 kN), full 360° azimuth capability, or operates in extreme wind/current conditions that exceed the thruster’s performance envelope.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CMP-TT-200 stern
unverified
· 200.0 kW
· tunnel thruster
Power (kW)
200
Thrust (kN)
24.0
Diameter (mm)
660
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (24 kN from 200 kW)
- Compact 660 mm tunnel fits vessels with limited hull space
- Caterpillar Marine Power brand reputation for durability and service support
Weaknesses
- Maximum thrust of 24 kN may be insufficient for very large ships or high‑speed DP operations
- Tunnel geometry can generate cavitation and hull vibration if not properly aligned
- Maintenance of tunnel bearings and seals required at regular intervals
Typical Vessels:
Offshore supply vesselContainer ship (up to 8,000 gt)FerryCruise ship (mid‑size)Bulk carrier (small to medium)
Decision Guide: Choose if you need a reliable, compact stern thruster delivering moderate thrust for vessels up to mid‑size and have limited hull space. Avoid if the vessel requires higher thrust (>30 kN), ultra‑low fuel consumption, or if you prefer azimuth pod solutions for full 360° thrust.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CMP-TT-250 bow
unverified
· 250.0 kW
· tunnel thruster
Power (kW)
250
Thrust (kN)
30.0
Diameter (mm)
700
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (30 kN at 250 kW) for its size
- Compact duct diameter (700 mm) fits into moderate hull openings
- Robust, low‑maintenance marine‑grade construction
- Integrated control electronics compatible with most bridge systems
- Relatively quiet operation compared with open‑propeller designs
Weaknesses
- Fixed thrust direction; cannot provide azimuthal thrust like a pod thruster
- Duct size may affect hull hydrodynamics and requires careful fairing
- Power draw is significant for vessels with limited electrical generation capacity
- Potential cavitation at high load if not properly sized to vessel speed
- Maintenance of tunnel bearings can be more involved than for rim‑drive units
Typical Vessels:
Container ships (up to ~150 m LOA)Bulk carriersGeneral cargo vesselsOffshore supply vesselsCruise ships and ferries requiring bow assistance
Decision Guide: Choose if you need a reliable, high‑thrust bow thruster for medium‑size vessels where space is limited and budget constraints preclude an azimuth unit. Avoid if the vessel requires 360° thrust vectoring, higher thrust levels (>35 kN), or operates in ultra‑quiet zones where cavitation risk must be minimal.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
CMP-TT-250 stern
unverified
· 250.0 kW
· electric tunnel thruster
Power (kW)
250
Thrust (kN)
30.0
Diameter (mm)
700
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (30 kN at 250 kW) for its size
- Compact 700 mm tunnel fits vessels with limited hull space
- Caterpillar’s proven reliability and global service network
- Integrated control electronics simplify installation and operation
- Robust sealed bearing design reduces maintenance intervals
Weaknesses
- Maximum thrust may be insufficient for large DP‑required vessels
- Potential cavitation noise at high RPM in shallow water
- Installation requires precise alignment of tunnel housing to hull
- Less maneuverability than azimuth or pod thrusters for tight turns
- Standard electric drive may not match the efficiency of newer hybrid systems
Typical Vessels:
Offshore supply vesselTugboat (medium size)Ro‑Ro ferryContainer ship (mid‑size, <10 000 gt)Bulk carrier (up to ~15 000 gt)
Decision Guide: Choose if you need a cost‑effective, low‑maintenance stern thruster for vessels under 15 000 gt where space is limited and DP requirements are modest. Avoid if the vessel requires higher thrust levels, advanced dynamic positioning, or the maneuverability of an azimuth pod.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CMP-TT-300 bow
unverified
· 300.0 kW
· hydraulic tunnel thruster
Power (kW)
300
Thrust (kN)
36.0
Diameter (mm)
740
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (36 kN at 300 kW) improves low‑speed handling
- Large 740 mm duct provides efficient water flow and reduced cavitation risk
- Cat Marine Power brand known for robust construction and long service life
- Modular mounting simplifies installation and later maintenance
- Suitable for integration with dynamic positioning (DP) systems
Weaknesses
- Relatively large duct diameter limits placement on vessels with tight hull space
- Requires a dedicated hydraulic power unit, adding to system complexity
- Higher initial capital cost compared with smaller tunnel units
- Potential for increased noise and vibration at full thrust
- Maintenance of bearings and seals is critical to avoid premature wear
Typical Vessels:
Offshore Supply VesselCruise ShipContainer ShipBulk CarrierTanker (up to mid‑size)
Decision Guide: Choose if the vessel needs high bow thrust for precise docking, dynamic positioning or maneuvering in confined ports and has sufficient hydraulic power capacity. Avoid if hull geometry cannot accommodate a 740 mm tunnel duct, the vessel is small where a lower‑power thruster would suffice, or project budgets are highly constrained.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CMP-TT-300 stern
unverified
· 300.0 kW
· tunnel thruster
Power (kW)
300
Thrust (kN)
36.0
Diameter (mm)
740
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (≈12 kN per 100 kW) for a compact unit
- Robust Caterpillar marine engineering with proven reliability
- Integrated control electronics compatible with most bridge systems
- Low vibration and noise levels compared with external propellers
- Standard class approvals simplify installation on new builds
Weaknesses
- Requires significant hull penetration; retro‑fit can be costly
- Fixed thrust direction – no 360° azimuth capability
- Maintenance of bearings and seals in the tunnel can be labour intensive
- Power draw may be higher than newer electric pod‑type thrusters for equivalent maneuverability
- Limited to stern locations due to size and flow characteristics
Typical Vessels:
Container shipBulk carrierProduct tankerCruise linerOffshore supply vessel
Certifications:
ABSDNV
Decision Guide: Choose if you need a high‑thrust, reliable stern thruster for vessels of 30 000–80 000 dwt that operate in tight ports or require dynamic positioning support. Avoid if the ship design cannot accommodate a tunnel installation, or if 360° thrust vectoring (azimuth) is required for maneuverability.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
CMP-TT-400 bow
unverified
· 400.0 kW
· tunnel thruster
Power (kW)
400
Thrust (kN)
48.0
Diameter (mm)
820
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (48 kN) relative to power consumption (400 kW)
- Large 820 mm duct diameter gives efficient water flow and reduced cavitation
- Bow placement enhances docking and tight‑port handling
- Cat Marine Power’s proven marine propulsion heritage
Weaknesses
- Requires substantial hull penetration, reducing usable internal volume
- Installation often needs additional structural reinforcement, raising cost
- Fixed‑direction thrust; less flexible than azimuth or pod thrusters for DP operations
- Potential for higher noise and vibration compared with newer low‑noise designs
Typical Vessels:
Container shipBulk carrierProduct tankerOffshore supply vesselRo‑Ro ferry
Decision Guide: Choose if you need strong bow thrust for vessels up to ~150 m LOA that operate in confined ports or require auxiliary maneuvering power. Avoid if hull space is at a premium, you need 360° thrust vectoring, or the vessel relies on advanced dynamic positioning where azimuth thrusters are preferred.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CMP-TT-400 stern
unverified
· 400.0 kW
· Tunnel thruster
Power (kW)
400
Thrust (kN)
48.0
Diameter (mm)
820
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (48 kN at 400 kW) provides strong maneuvering capability.
- Large 820 mm tunnel diameter reduces cavitation and improves hydraulic efficiency.
- Robust stainless‑steel housing resists corrosion in harsh marine environments.
- Integrated control electronics compatible with most ship bridge systems.
Weaknesses
- Significant hull penetration required; installation space is limited on smaller ships.
- High electrical demand may necessitate upgrades to the vessel’s power generation plant.
- Weight and structural reinforcement increase overall construction cost.
- Spare‑part logistics can be challenging for vessels operating in remote regions.
Typical Vessels:
Container shipBulk carrierTankerCruise linerOffshore support vessel
Decision Guide: Choose if the vessel needs strong stern thrust for dynamic positioning, tight‑dock maneuvering or redundancy in a twin‑thruster arrangement. Avoid on small craft where hull space and power availability are limited, or when a lower‑cost, lower‑thrust solution suffices.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CMP-TT-500 bow
unverified
· 500.0 kW
· tunnel thruster
Power (kW)
500
Thrust (kN)
60.0
Diameter (mm)
900
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (60 kN) relative to power rating provides excellent docking assistance.
- Compact 900 mm tunnel diameter fits into moderate hull spaces, allowing installation on a wide range of vessels.
- Cat Marine Power brand reputation for reliability and long service intervals.
- Integrated control electronics simplify wiring and enable precise thrust modulation.
- Tunnel design offers lower acoustic signature compared with some external propeller‑type thrusters.
Weaknesses
- Requires hull penetration; installation can be complex and may affect structural integrity if not properly reinforced.
- Efficiency drops in very shallow water due to increased suction on the tunnel inlet/outlet.
- Power consumption (500 kW) is significant; vessels must allocate dedicated generator capacity.
- Limited 360° thrust vectoring – only provides lateral force, unlike azimuth thrusters.
- Maintenance access can be restricted in tight engine‑room layouts.
Typical Vessels:
Container shipsBulk carriersGeneral cargo vesselsCruise liners (mid‑size)Offshore supply vessels
Decision Guide: Choose if: the vessel requires strong bow thrust for port docking, dynamic positioning support, or maneuvering in confined waterways and has sufficient hull space for a 900 mm tunnel. Avoid if: the ship operates in extremely shallow drafts where suction losses are critical, needs full‑circle thrust capability, or prefers azimuth pod solutions for higher efficiency.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
CMP-TT-500 stern
unverified
· 500.0 kW
· tunnel thruster
Power (kW)
500
Thrust (kN)
60.0
Diameter (mm)
900
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (60 kN from 500 kW) for rapid low‑speed positioning
- Compact 900 mm duct diameter fits into limited hull space at the stern
- Robust stainless‑steel construction and Cat Marine Power’s integrated control package
- Low vibration and noise levels compared with conventional propeller‑type thrusters
- Proven reliability in Cat Marine Power’s product line for commercial vessels
Weaknesses
- 500 kW power demand requires dedicated generator capacity or high‑capacity electrical bus
- Installation involves significant hull penetration and structural reinforcement
- Maintenance of high‑load bearings and seals can be intensive on a busy schedule
- Fixed‑direction thrust limits maneuverability compared with azimuth thrusters
- Limited thrust increase options without upgrading to a larger tunnel size
Typical Vessels:
Crude oil tankerProduct tankerContainer shipBulk carrierCruise linerOffshore supply vessel
Decision Guide: Choose if the vessel needs a powerful, compact stern thruster for tight berthing and has sufficient electrical power capacity. Avoid if hull space is extremely constrained, if variable thrust direction is required for dynamic positioning, or if lower installation cost and simpler maintenance are higher priorities.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CMP-TT-600 bow
unverified
· 600.0 kW
· tunnel thruster
Power (kW)
600
Thrust (kN)
72.0
Diameter (mm)
980
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust-to‑power ratio (72 kN at 600 kW) for rapid lateral movement
- Large 980 mm tunnel diameter reduces cavitation and improves efficiency
- Integrated Cat Marine Power control unit with built‑in fault diagnostics
- Robust, corrosion‑resistant construction suited to harsh sea conditions
- Standard bow‑thruster footprint compatible with many new‑build designs
Weaknesses
- Physical size requires ample hull volume; unsuitable for small vessels
- 600 kW power demand may necessitate dedicated generator capacity and raises fuel use
- Precise installation alignment is critical, making retrofits costly and time‑consuming
- Noise and vibration levels higher than some low‑speed propeller thrusters
- Access for routine maintenance can be limited by tunnel placement
Typical Vessels:
Container ShipBulk CarrierTankerCruise ShipOffshore Supply VesselLNG Carrier
Certifications:
IMO Type Approval
Decision Guide: Choose if you need high lateral thrust for port entry/exit, dynamic positioning or emergency maneuvering on large vessels and have sufficient hull space and power supply. Avoid if the vessel is size‑restricted, power budget is limited, or a quieter low‑speed thruster is preferred.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
CMP-TT-600 stern
unverified
· 600.0 kW
· tunnel thruster
Power (kW)
600
Thrust (kN)
72.0
Diameter (mm)
980
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (≈72 kN at 600 kW) for rapid berthing and unberthing.
- Compact tunnel design fits into limited hull space while providing robust protection to the propeller.
- Integrated motor‑generator with optional variable frequency drive enables fine speed control and reduced fuel consumption.
- Proven reliability of Caterpillar’s marine power systems; low maintenance intervals.
- Standard class approvals (ABS, DNV) simplify installation on new builds.
Weaknesses
- Large duct diameter (~1 m) may limit applicability on vessels with narrow hull sections.
- Higher initial capital cost compared with conventional fixed propeller thrusters of similar power.
- Requires dedicated cooling and ventilation systems, adding to installation complexity.
- Fixed‑direction thrust; cannot provide 360° vectoring like azimuth pods for dynamic positioning.
- Noise and vibration levels are higher than some low‑speed azimuth units in certain operating regimes.
Typical Vessels:
Crude oil tankerProduct tankerContainer shipBulk carrierCruise linerOffshore supply vessel
Certifications:
ABS Type ApprovalDNV GL Classification
Decision Guide: Choose if you need high static thrust for berthing/unberthing on large vessels, have sufficient hull space for a ~1 m tunnel, and prefer a proven, low‑maintenance solution with class approvals. Avoid if the vessel requires omnidirectional thrust for dynamic positioning, has tight hull constraints that preclude a 980 mm duct, or if budget constraints favor lower‑cost fixed propeller thrusters.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CMP-TT-750 bow
unverified
· 750.0 kW
· tunnel thruster
Power (kW)
750
Thrust (kN)
90.0
Diameter (mm)
1100
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (≈90 kN at 750 kW) for rapid lateral movements
- Robust tunnel construction with corrosion‑resistant lining, suited to harsh marine environments
- Integrated control electronics compatible with most ship bridge systems
- Low vibration and noise levels compared with conventional propeller‑type thrusters
- Proven track record on cruise ships, LNG carriers and offshore support vessels
Weaknesses
- Large tunnel diameter (≈1.1 m) can restrict hull form options and increase structural reinforcement needs
- Higher electrical power demand may require upgraded shipboard generators
- Installation requires precise alignment of the tunnel duct, increasing fit‑out time
- Maintenance access is limited to the tunnel interior, requiring specialized tools
- Capital cost is higher than lower‑power thruster alternatives
Typical Vessels:
Cruise ShipLNG CarrierOffshore Supply VesselContainer Ship (≥8 000 TEU)Large Bulk Carrier
Decision Guide: Choose if: you need >80 kN thrust on a vessel ≥150 m LOA, have sufficient hull space for a 1.1 m tunnel, and require low‑noise maneuvering in ports or offshore terminals. Avoid if: the ship’s power plant cannot accommodate an additional 750 kW load, hull geometry limits large tunnel installations, or budget constraints favour smaller thrusters.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
CMP-TT-750 stern
unverified
· 750.0 kW
· hydraulic tunnel thruster
Power (kW)
750
Thrust (kN)
90.0
Diameter (mm)
1100
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust output (≈90 kN) for a single unit, enabling rapid stern‑side manoeuvring on large ships
- Robust Cat Marine Power construction with proven reliability in harsh marine environments
- Integrated cooling and sealed bearing system reduces maintenance intervals
- Standard 1100 mm tunnel diameter fits common hull openings for new‑build installations
Weaknesses
- Large tunnel size can compromise hull strength if not properly reinforced during installation
- High power demand (750 kW) may require substantial electrical or hydraulic plant upgrades on older vessels
- Installation space at the stern is considerable; retrofits on existing ships can be complex and costly
- Noise and vibration levels are higher than smaller thrusters, requiring additional acoustic mitigation for passenger‑focused vessels
Typical Vessels:
Crude Oil TankerLNG CarrierContainer Ship (>150 m LOA)Cruise ShipOffshore Supply Vessel (DP2/DP3)
Decision Guide: Choose if: the vessel needs a high‑thrust stern thruster for DP operations, tight berthing or rapid repositioning and has sufficient space/power plant capacity. Avoid if: hull geometry limits tunnel size, power plant cannot accommodate 750 kW, or acoustic noise must be kept to a minimum.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CMP-TT-800 bow
unverified
· 800.0 kW
· high‑power tunnel thruster
Power (kW)
800
Thrust (kN)
96.0
Diameter (mm)
1140
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (96 kN at 800 kW) for rapid lateral movement
- Robust Caterpillar engine platform with global service network
- Tunnel design reduces cavitation and vibration compared with external propellers
- Integrated control electronics compatible with most ship bridge systems
- Proven reliability on a range of deep‑draft vessels
Weaknesses
- Large duct diameter (1.14 m) requires significant hull penetration and structural reinforcement
- High power consumption may increase fuel use during frequent thruster operation
- Installation space at the bow can be limited on smaller or retro‑fit ships
- Maintenance of bearings and seals in a high‑load tunnel environment can be intensive
- Initial procurement cost is higher than lower‑power alternatives
Typical Vessels:
Container shipBulk carrierTankerCruise linerOffshore supply vessel
Decision Guide: Choose if: you need a high‑thrust bow thruster for vessels over ~150 m LOA, operate in confined ports or require dynamic positioning assistance, and value Caterpillar's global support. Avoid if: the ship’s hull cannot accommodate a 1.14 m tunnel, power budget is tight, or the vessel size does not justify the thrust level.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CMP-TT-800 stern
unverified
· 800.0 kW
· tunnel thruster
Power (kW)
800
Thrust (kN)
96.0
Diameter (mm)
1140
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (96 kN at 800 kW) improves manoeuvrability
- Robust stainless‑steel duct and propeller resist marine corrosion
- Integrated variable‑frequency drive provides fine speed control and energy efficiency
- Optimised blade geometry reduces cavitation risk during low‑speed operation
- Installed on several large commercial vessels, demonstrating field reliability
Weaknesses
- Large 1.14 m diameter requires a substantial hull cut‑out, limiting retrofit options
- High power rating can increase fuel consumption if used continuously
- Spare parts and service are primarily through Cat Marine Power’s network, which may be limited in remote ports
- Significant mounting loads demand reinforced stern structure and careful weight distribution
- Control system integration may require custom interfacing with existing ship automation
Typical Vessels:
Container ShipBulk CarrierTankerCruise ShipOffshore Support Vessel
Decision Guide: Choose the CMP‑TT‑800 when a vessel needs high thrust for stern manoeuvring, has sufficient hull space for a 1.14 m duct, and values proven performance on large commercial ships. Avoid if retrofitting tight hulls, limited access to Cat Marine Power service centres, or when lower power/size thrusters meet the manoeuvre requirements.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
CMP-TT-1000 bow
unverified
· 1000.0 kW
· high‑power tunnel thruster
Power (kW)
1000
Thrust (kN)
120.0
Diameter (mm)
1300
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (≈120 kN) suitable for large vessels and DP operations
- Large 1300 mm duct diameter reduces cavitation and improves efficiency
- Integrated control electronics compatible with most bridge automation systems
- Robust Cat Marine Power design known for long service intervals
Weaknesses
- High electrical power demand (≈1 MW) may require substantial generator capacity
- Large hull penetration can complicate installation on vessels with limited bow space
- Weight and size increase overall vessel weight and affect stability calculations
- Maintenance access to the internal impeller is more difficult than for smaller units
Typical Vessels:
Container ships (>8,000 TEU)Cruise linersOffshore supply vesselsLNG carriersLarge bulk carriers
Decision Guide: Choose if the vessel requires >100 kN bow thrust for tight berthing, dynamic positioning or ice‑class operations and has sufficient power generation capacity. Avoid if hull form limits large duct installations, power budget is constrained, or a smaller, lower‑cost thruster meets maneuverability needs.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CMP-TT-1000 stern
unverified
· 1000.0 kW
· tunnel thruster
Power (kW)
1000
Thrust (kN)
120.0
Diameter (mm)
1300
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (120 kN) relative to power rating, enabling rapid stern‑side manoeuvring.
- Large 1300 mm diameter reduces cavitation risk and improves efficiency at high thrust levels.
- Robust Cat Marine Power construction with proven service life in harsh marine environments.
- Integrated control interface compatible with most ship bridge systems for precise handling.
Weaknesses
- Physical size (1.3 m duct) limits installation to vessels with sufficient hull space aft.
- High power demand (1 MW) increases fuel consumption and may require dedicated electrical capacity.
- Tunnel thrusters can generate significant noise and vibration, requiring additional mitigation measures.
- Maintenance access is more complex than for smaller azimuth units due to the large duct and bearing arrangement.
Typical Vessels:
Cruise shipContainer vessel (large class)Offshore supply vesselLNG carrierFPSO
Decision Guide: Choose if the vessel needs a powerful stern‑side thrust source for tight‑port docking, dynamic positioning assistance, or emergency manoeuvring and has sufficient hull volume to accommodate a 1.3 m tunnel unit. Avoid if the ship is size‑restricted, budget‑constrained, or can achieve required maneuverability with smaller azimuth thrusters.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CMP-TT-1200 bow
unverified
· 1200.0 kW
· tunnel bow thruster
Power (kW)
1200
Thrust (kN)
144.0
Diameter (mm)
1460
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust output (144 kN) relative to its 1 200 kW power rating
- Large 1.46 m tunnel diameter improves hydraulic efficiency and reduces cavitation risk
- Cat Marine Power’s proven mechanical design offers long service intervals and robust construction
- Standard bow‑mounting geometry fits easily into new‑build hull designs
Weaknesses
- Requires a sizable hull penetration and associated structural reinforcement, raising installation cost
- Overall unit weight is high, affecting stability calculations on smaller platforms
- Spare‑parts logistics can be slower in remote regions compared with more widely stocked thruster brands
- May need dedicated cooling‑water arrangements not present on all vessels
Typical Vessels:
Container ship (≥30 000 GT)Crude oil tankerLNG carrierBulk carrier (≥50 000 DWT)Cruise linerOffshore supply vessel
Decision Guide: Choose if: you need a bow thruster that can deliver >140 kN thrust on a large commercial vessel and are willing to accommodate the larger hull opening. Avoid if: vessel size or draft limits the installation of a 1.46 m tunnel, or if spare‑part availability in remote ports is a critical concern.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CMP-TT-1200 stern
unverified
· 1200.0 kW
Power (kW)
1200
Thrust (kN)
144.0
Diameter (mm)
1460
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (144 kN) suitable for large vessels and DP‑assisted operations
- Robust Caterpillar engineering with proven reliability in harsh marine environments
- Integrated control electronics compatible with common bridge consoles
- Large duct diameter provides efficient water flow, reducing cavitation risk
Weaknesses
- Physical size (1.46 m diameter) limits installation to vessels with sufficient hull space
- High power rating (1200 kW) leads to significant electrical load and fuel consumption
- Potentially higher upfront cost compared with lower‑power competitors
- Noise and vibration levels can be elevated if not fitted with acoustic mitigation
Typical Vessels:
Container shipsCruise linersLarge offshore supply vesselsLNG carriersRo‑Ro ferries
Decision Guide: Choose if the vessel requires maximum stern thrust for tight port manoeuvring, dynamic positioning or has existing Caterpillar power‑train infrastructure. Avoid if hull space is limited, budget constraints are primary, or a lower‑power thruster would meet the maneuverability requirements.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CMP-TT-1500 bow
unverified
· 1500.0 kW
· high‑power tunnel thruster
Power (kW)
1500
Thrust (kN)
180.0
Diameter (mm)
1700
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (180 kN) suitable for large vessels and tight port operations
- Large 1700 mm tunnel provides efficient water flow and reduced cavitation
- Robust Cat Marine Power design with proven reliability in harsh marine environments
- Integrated bow location minimizes hull penetration points compared to external azimuth units
Weaknesses
- Large tunnel diameter consumes significant hull volume, affecting cargo space or structural layout
- High power rating (1500 kW) leads to substantial electrical demand and cooling requirements
- Installation is complex and may require extensive hull modifications
- Less flexible than azimuth thrusters for 360° thrust vectoring
Typical Vessels:
Aframax TankerPanamax Container ShipCruise VesselOffshore Supply VesselLNG Carrier
Decision Guide: Choose if: you need maximum bow thrust for a vessel >30 000 gt, have sufficient hull beam to accommodate a 1.7 m tunnel, and prefer the reliability of a Cat Marine Power system. Avoid if: vessel size or hull form limits tunnel installation, budget constraints favor smaller thrusters, or you require full‑circle thrust vectoring offered by azimuth units.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CMP-TT-1500 stern
unverified
· 1500.0 kW
· tunnel thruster
Power (kW)
1500
Thrust (kN)
180.0
Diameter (mm)
1700
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (180 kN) for its power rating (1500 kW), suitable for large vessels
- Large 1700 mm tunnel diameter improves flow efficiency and reduces cavitation risk
- Optimised for stern installation, aiding reverse docking and low‑speed control
- Backed by Cat Marine Power’s global service network and proven reliability
Weaknesses
- High electrical power demand (1500 kW) requires substantial onboard supply infrastructure
- Physical size may limit installation on smaller hulls or retrofit projects
- Tunnel thrusters provide thrust only in a fixed direction, less flexible than azimuth pods for some manoeuvres
- Potential for vibration and noise if mounting is not properly engineered
Typical Vessels:
Container ShipBulk CarrierTankerCruise ShipOffshore Support Vessel
Decision Guide: Choose if you need a proven, high‑thrust stern thruster for large vessels and have the electrical capacity to support 1500 kW; avoid if space is constrained, power budget is limited, or you require 360° thrust capability offered by azimuth units.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CMP-TT-2000 bow
unverified
· 2000.0 kW
· tunnel bow thruster
Power (kW)
2000
Thrust (kN)
240.0
Diameter (mm)
2100
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust output (240 kN) suitable for large vessels and tight port operations
- Large duct diameter reduces cavitation risk and improves efficiency at high power levels
- Robust Cat Marine Power design with proven reliability in harsh marine environments
- Integrated control interface compatible with most ship‑board maneuvering systems
Weaknesses
- Large physical size limits installation to vessels with sufficient hull space forward of the bow
- High electrical demand (≈2 MW) requires substantial power generation and distribution capacity
- Installation and alignment are complex, increasing dockyard time and cost
- Noise and vibration levels can be higher than smaller thrusters, requiring additional mitigation
Typical Vessels:
Container shipBulk carrierTankerCruise linerOffshore support vessel
Decision Guide: Choose if you need maximum bow‑thruster thrust for vessels >150 m LOA operating in confined ports or requiring dynamic positioning. Avoid if the ship’s power plant cannot supply ~2 MW dedicated to a thruster, or if hull space at the bow is limited.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CMP-TT-2000 stern
unverified
· 2000.0 kW
· Tunnel thruster
Power (kW)
2000
Thrust (kN)
240.0
Diameter (mm)
2100
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust‑to‑power ratio (≈240 kN at 2 MW) for rapid maneuvering
- Compact 2100 mm tunnel diameter fits into limited stern space on large vessels
- Integrated variable‑frequency drive and monitoring system reduces wiring and simplifies control
- Cat Marine’s proven reliability record and global service network
- Low‑cavitation blade design minimises noise and vibration, beneficial for DP operations
Weaknesses
- Large power demand requires substantial electrical supply capacity
- Physical size and weight limit installation to medium‑to‑large vessels only
- Higher upfront cost compared with lower‑power thrusters
- Requires dedicated ducting and structural reinforcement in the hull
- Water‑lubricated bearing system demands regular inspection and water quality control
Typical Vessels:
Cruise shipLNG carrierOffshore supply vessel (OSV)Large container shipBulk carrier (≥150 kt)
Certifications:
DNV GLABS
Decision Guide: Choose if the vessel needs high‑thrust maneuverability or DP support and has sufficient electrical capacity and stern space; avoid on small to medium vessels where power, space or budget constraints make a lower‑rated thruster more appropriate.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
CMP-TT-2500 bow
unverified
· 2500.0 kW
Power (kW)
2500
Thrust (kN)
300.0
Diameter (mm)
2500
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- 300 kN of thrust gives excellent maneuvering force for very large ships.
- Large 2.5 m tunnel diameter reduces cavitation risk and improves efficiency at high power.
- 2500 kW rating matches the electrical generation capacity of modern mega‑vessels.
Weaknesses
- High power demand (2.5 MW) increases the vessel’s overall energy consumption.
- The size of the tunnel requires substantial hull penetration and structural reinforcement.
- Installation, commissioning and maintenance costs are higher than for smaller thrusters.
Typical Vessels:
Very Large Crude Carrier (VLCC)Ultra‑Large Container ShipCruise ShipLNG CarrierOffshore Supply Vessel
Decision Guide: Choose if: you need a bow thruster capable of delivering >300 kN thrust for vessels over ~80,000 DWT, have sufficient electrical generation capacity and can accommodate the large tunnel opening. Avoid if: the ship is smaller, power budget is limited, or hull space cannot be modified for a 2.5 m duct.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CMP-TT-2500 stern
unverified
· 2500.0 kW
· electric tunnel thruster
Power (kW)
2500
Thrust (kN)
300.0
Diameter (mm)
2500
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (≈300 kN) for its size, enabling rapid stern‑side manoeuvres on large vessels
- Integrated variable‑frequency drive provides fine thrust control and energy efficiency
- Low acoustic signature and vibration – important for passenger ships and offshore workboats
- Robust stainless‑steel tunnel housing resists corrosion in harsh marine environments
- Modular design simplifies installation and routine maintenance
Weaknesses
- Requires a substantial electrical power supply (≈2.5 MW) and high‑voltage distribution infrastructure
- Large 2.5 m tunnel diameter may limit fitment on vessels with restricted hull space
- Higher capital cost compared with conventional diesel‑driven thrusters of similar rating
- Potential for cavitation if operated continuously at maximum thrust in shallow water
- Weight and size add to overall stern structure reinforcement requirements
Typical Vessels:
Cruise shipsLNG carriersLarge container vessels (>150 kTEU)Bulk carriers (>180 kt)Offshore supply & anchor handling tug supply (AHTS) vessels
Decision Guide: Choose if the vessel needs high‑power stern manoeuvring, has ample electrical generation capacity and values low noise/vibration – e.g., cruise liners, LNG carriers or DP‑enabled offshore vessels. Avoid if hull geometry cannot accommodate a 2.5 m tunnel, the ship’s power plant is limited, or budget constraints preclude the higher upfront cost.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CMP-TT-3000 bow
unverified
· 3000.0 kW
Power (kW)
3000
Thrust (kN)
360.0
Diameter (mm)
2900
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (360 kN) suitable for vessels >150 000 dwt requiring strong bow assistance
- Compact tunnel diameter (2.9 m) allows installation on ships with limited hull space
- Electric drive provides low noise and vibration compared with hydraulic systems
- Integrated control electronics simplify operator handling and enable precise thrust vectoring
- Designed for continuous high‑power operation, offering good reliability in demanding conditions
Weaknesses
- Requires a substantial shipboard electrical power plant (≈3 MW) and associated cooling infrastructure
- Installation involves significant hull reinforcement and duct integration work
- Higher upfront cost than smaller or lower‑power thruster options
- Large duct size may limit applicability on vessels with tight bow geometry
- Maintenance of high‑capacity electric motor and power electronics can be specialised
Typical Vessels:
Very Large Crude Carriers (VLCC)Ultra‑large Container ShipsCruise LinersOffshore Supply Vessels (OSV)FPSOs and large LNG carriers
Decision Guide: Choose if: you need maximum bow thrust for a vessel >150 000 dwt, have sufficient electrical generation capacity, and require low‑noise manoeuvring. Avoid if: the ship’s power plant cannot support an additional ~3 MW load, hull space is limited, or budget constraints favour smaller thrusters.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CMP-TT-3000 stern
unverified
· 3000.0 kW
· high‑power tunnel thruster
Power (kW)
3000
Thrust (kN)
360.0
Diameter (mm)
2900
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (360 kN) suitable for large vessels and DP operations
- Robust Caterpillar engineering with proven field reliability
- Large 2.9 m duct diameter reduces cavitation and improves efficiency
- Integrated control interface compatible with most bridge systems
- Designed for stern installation, freeing bow space for other equipment
Weaknesses
- Large physical size requires substantial hull cut‑out and structural reinforcement
- High power demand (3 MW) increases fuel consumption and electrical load
- Installation and commissioning costs are significant
- Noise and vibration levels can be higher than smaller thrusters
- Spare‑part logistics may be slower for remote ports
Typical Vessels:
Cruise shipLNG carrierVery large crude carrier (VLCC)Ultra‑large container vesselOffshore support vessel
Decision Guide: Choose if the vessel requires >300 kN of stern thrust for tight harbor turns, dynamic positioning or emergency maneuverability and has sufficient hull space for a 2.9 m duct. Avoid if the ship is smaller, power‑limited, or cannot accommodate the structural modifications needed for a large tunnel thruster.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
CMP-TT-3500 bow
unverified
· 3500.0 kW
· electric tunnel thruster
Power (kW)
3500
Thrust (kN)
420.0
Diameter (mm)
3300
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (420 kN) at 3.5 MW enables rapid sideways movement of large vessels.
- Large 3.3 m duct diameter provides efficient water flow and reduces cavitation risk.
- Integrated variable‑frequency drive offers precise thrust control and energy savings.
- Bow‑mount configuration improves docking and port manoeuvring for deep‑draft ships.
- Caterpillar brand reliability with a global service and spare‑parts network.
Weaknesses
- Requires substantial shipboard electrical supply and cooling infrastructure.
- Physical size limits installation on smaller hulls or retrofits with limited space.
- Higher capital cost compared with lower‑power thruster options.
- Large flow rate can increase duct fouling, necessitating regular cleaning.
- Complex drive electronics may need specialised maintenance personnel.
Typical Vessels:
Very Large Crude Carrier (VLCC)LNG CarrierCruise ShipContainer Ship (>150,000 TEU)Offshore Supply Vessel
Decision Guide: Choose if: you need maximum bow thrust for vessels >150 kDWT, frequent port entry/exit in confined harbours, or dynamic positioning support. Avoid if: the ship lacks sufficient electrical generation capacity, space constraints prevent a 3.3 m duct installation, or budget limits preclude high‑power thrusters.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CMP-TT-3500 stern
unverified
· 3500.0 kW
· tunnel thruster
Power (kW)
3500
Thrust (kN)
420.0
Diameter (mm)
3300
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust output (420 kN) suitable for large ships and DP operations
- High power rating (3.5 MW) provides rapid response during low‑speed maneuvers
- Robust Caterpillar engineering with proven reliability in harsh marine environments
- Large 3.3 m duct diameter gives good thrust efficiency while keeping a relatively compact footprint for its power class
Weaknesses
- Requires substantial electrical generation capacity and cooling infrastructure on board
- Large duct size may limit installation in vessels with restricted hull space at the stern
- Higher maintenance complexity due to high‑power drive components
- Elevated fuel consumption when operated frequently at full power
Typical Vessels:
Very Large Crude Carrier (VLCC)LNG carrierCruise shipOffshore supply vesselLarge container ship
Decision Guide: Choose if: you need a high‑thrust stern thruster for vessels >150 m LOA, have sufficient onboard power generation, and require precise low‑speed maneuvering or dynamic positioning. Avoid if: the vessel is small to medium size with limited stern space, power plant cannot support 3.5 MW auxiliary loads, or cost/maintenance budget is constrained.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
CMP-TT-4000 bow
unverified
· 4000.0 kW
· tunnel thruster
Power (kW)
4000
Thrust (kN)
480.0
Diameter (mm)
3700
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (≈480 kN) suitable for mega‑vessels and tight port operations
- Robust Caterpillar marine‑grade construction with long service intervals
- Integrated control electronics compatible with most DP and bridge systems
- Relatively low acoustic signature compared with external azimuth pods
- Proven track record on cruise ships, LNG carriers and offshore support vessels
Weaknesses
- Large duct diameter limits installation to vessels with sufficient hull space
- High power demand (4 MW) increases fuel consumption and requires substantial cooling water flow
- Higher upfront cost than smaller thrusters or basic fixed‑pitch propellers
- Spare‑part logistics can be challenging in remote ports without Caterpillar support depots
- Installation and alignment are complex, requiring specialised shipyard facilities
Typical Vessels:
Cruise ShipLNG CarrierOffshore Supply Vessel (OSV)Heavy‑Lift / Project Cargo VesselLarge Ro‑Ro Ferry
Certifications:
ABSDNV GL
Decision Guide: Choose if the vessel requires very high bow thrust for safe docking in confined ports, operates under dynamic positioning, or needs a proven, low‑noise solution on a large hull. Avoid if the ship’s beam cannot accommodate a 3.7 m duct, budget constraints favour a smaller thruster, or an azimuth pod offers better all‑directional thrust for the intended operation.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CMP-TT-4000 stern
unverified
· 4000.0 kW
· tunnel thruster
Power (kW)
4000
Thrust (kN)
480.0
Diameter (mm)
3700
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust output (480 kN) suitable for the largest ships
- Compact tunnel design fits within hull structure while providing strong lateral force
- Caterpillar’s proven reliability and extensive service network
- Integrated control electronics compatible with most DP and bridge systems
- Easy access for routine inspection and maintenance
Weaknesses
- Large 3.7 m diameter may limit installation in vessels with restricted hull space
- High power demand (4 MW) increases fuel consumption when used extensively
- Requires substantial cooling‑water flow; not ideal for vessels with limited intake capacity
- Potential cavitation at full load if propeller design is not optimised for local water conditions
- Higher upfront capital cost compared to lower‑power thruster options
Typical Vessels:
Very Large Crude Carrier (VLCC)Ultra Large Container Vessel (ULCV)Cruise ShipOffshore Support VesselLNG Carrier
Certifications:
IMO Type ApprovalDNV Class Approval
Decision Guide: Choose if the vessel requires maximum thrust for safe docking/undocking in confined ports, dynamic positioning support, or emergency backup propulsion on a high‑displacement ship. Avoid if hull geometry cannot accommodate a 3.7 m tunnel unit, power availability is limited, or a lower‑cost, lower‑thrust solution meets operational needs.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CMP-TT-4500 bow
unverified
· 4500.0 kW
Power (kW)
4500
Thrust (kN)
540.0
Diameter (mm)
4100
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust output (540 kN) suitable for the largest merchant ships
- Large duct diameter (4.1 m) provides efficient water flow and reduced cavitation risk
- Integrated with Cat Marine Power’s control and monitoring suite for precise handling
- Designed for 4500 kW power rating, matching high‑capacity shipboard power plants
- Proven brand reputation for reliability in demanding offshore environments
Weaknesses
- Physical size limits installation to vessels with sufficient bow space
- High power demand requires robust electrical or hydraulic supply infrastructure
- Installation and commissioning costs are higher than smaller thruster units
- Spare‑part logistics may be less widespread than for more common low‑power models
Typical Vessels:
Very Large Crude Carrier (VLCC)Ultra Large Container Vessel (ULCV)Cruise ShipLNG CarrierOffshore Supply Vessel
Decision Guide: Choose if: you need maximum bow thrust for a vessel >150 m LOA operating in restricted ports or requiring dynamic positioning support. Avoid if: the ship’s bow space is limited, power plant cannot supply 4.5 MW to a thruster, or budget constraints favor lower‑power alternatives.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
CMP-TT-4500 stern
unverified
· 4500.0 kW
· tunnel thruster
Power (kW)
4500
Thrust (kN)
540.0
Diameter (mm)
4100
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust output (540 kN) suitable for the maneuvering needs of mega‑size tankers and cruise ships
- Large 4.1 m tunnel diameter reduces cavitation risk and improves hydraulic efficiency
- Cat Marine Power’s reputation for robust, low‑maintenance marine propulsion equipment
- Integrated variable‑frequency drive (VFD) capability provides fine thrust control and energy optimisation
Weaknesses
- High electrical power demand (4.5 MW) requires a substantial shipboard power plant and cabling infrastructure
- Large physical footprint may limit installation on vessels with constrained hull space or during retrofit projects
- Initial capital cost is higher than smaller‑capacity thrusters, impacting budget for mid‑size ships
- Spare‑part logistics can be more complex if the vessel operates far from Cat Marine Power service networks
Typical Vessels:
VLCC / ULCC tankersLarge LNG carriersUltra‑large container vessels (10,000+ TEU)Cruise ships (>2000 passengers)Offshore support vessels with DP2/DP3 requirements
Decision Guide: Choose if the vessel requires very high stern thrust for safe docking in confined ports or as part of a dynamic positioning system and can accommodate a 4.5 MW electrical load and the physical size of a 4.1 m tunnel. Avoid on smaller ships, vessels with limited power generation capacity, or where hull space does not permit a large tunnel installation.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CMP-TT-5000 bow
unverified
· 5000.0 kW
· tunnel thruster
Power (kW)
5000
Thrust (kN)
600.0
Diameter (mm)
4500
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (≈600 kN) suitable for maneuvering mega‑vessels
- Large 4.5 m duct provides efficient water flow and low cavitation
- Cat Marine’s proven reliability and global service network
- Integrated control system compatible with most DP packages
- Robust construction designed for harsh marine environments
Weaknesses
- Physical size limits installation to vessels with sufficient bow space
- High power demand (≈5 MW) increases fuel consumption and electrical load
- Capital cost is higher than lower‑power alternatives
- Requires substantial cooling and ventilation infrastructure
- Maintenance access can be challenging on very crowded hull forms
Typical Vessels:
Cruise shipLNG carrierFPSO / offshore support vesselLarge container shipVery large bulk carrier
Decision Guide: Choose if: you need very high bow thrust for a mega‑vessel, have sufficient hull space for a 4.5 m tunnel, and can accommodate the electrical power budget. Avoid if: vessel size or power plant cannot support a 5 MW thruster, or installation space is constrained.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
CMP-TT-5000 stern
unverified
· 5000.0 kW
· high-power tunnel thruster
Power (kW)
5000
Thrust (kN)
600.0
Diameter (mm)
4500
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (≈600 kN) suitable for large vessels and DP operations
- Robust, marine‑grade construction with corrosion‑resistant alloys
- Integrated control electronics compatible with common ship bridge systems
- Modular design allows relatively quick installation and maintenance access
- Low cavitation design reduces blade wear and improves efficiency
Weaknesses
- Large physical envelope (4.5 m diameter) limits use on vessels with restricted hull space
- High power rating leads to significant electrical demand and associated infrastructure cost
- Tunnel geometry can be less efficient than azimuth thrusters in very shallow water
- Initial capital cost is higher than lower‑power tunnel units
Typical Vessels:
Very Large Crude Carriers (VLCC)LNG carriersCruise shipsOffshore supply vesselsLarge container ships requiring DP or high‑precision docking
Decision Guide: Choose if: you need maximum thrust for a large vessel, have sufficient electrical capacity, and prefer a proven tunnel design with integrated control. Avoid if: hull space is limited, budget constraints favor smaller thrusters, or an azimuth/azipod solution better matches your maneuverability requirements.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Holland Roer Propeller
44
HRP-TT-50 bow
unverified
· 50.0 kW
· tunnel thruster
Power (kW)
50
Thrust (kN)
6.0
Diameter (mm)
540
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Compact installation footprint suitable for retrofit on existing hulls
- High hydraulic efficiency gives good thrust per kW
- Low acoustic signature, beneficial for crew comfort and marine life
- Robust stainless‑steel duct reduces corrosion in saltwater environments
- Standardized mounting interface simplifies integration
Weaknesses
- Maximum thrust (≈6 kN) may be insufficient for large vessels or heavy‑load tugs
- Susceptible to debris ingestion if operating in fouled waters without proper grates
- Limited ice‑class capability; not recommended for arctic operations
- Maintenance access requires removal of the duct cover, adding downtime
Typical Vessels:
Offshore Supply VesselCoastal FerryWorkboat / Service CraftSmall Container FeederCoastal Tanker (≤5 000 GT)
Certifications:
DNVABS
Decision Guide: Choose if: you need a reliable, space‑saving bow thruster for vessels up to ~5 000 GT with moderate thrust requirements and want low noise and easy retrofit. Avoid if: the vessel demands high thrust (>10 kN), operates in ice or heavy debris conditions, or requires an ice‑class approved thruster.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
HRP-TT-50 stern
unverified
· 50.0 kW
· hydraulic tunnel thruster
Power (kW)
50
Thrust (kN)
6.0
Diameter (mm)
540
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Compact 540 mm diameter fits in limited hull spaces
- 6 kN thrust sufficient for medium‑size vessels and tight port operations
- Hydraulic drive offers smooth, controllable thrust with low vibration
- Relatively low power consumption (50 kW) compared with higher‑rated thrusters
Weaknesses
- Maximum thrust of 6 kN may be inadequate for large tankers or high‑wind conditions
- Requires integration of a hydraulic power unit, adding system complexity
- Maintenance of bearings and seals in the tunnel can be demanding in harsh marine environments
- Limited redundancy if only a single stern thruster is installed
Typical Vessels:
Coastal tankerContainer feederGeneral cargo shipOffshore supply vesselWorkboat / tug‑assist craft
Decision Guide: Choose if: you need a compact, moderate‑power thruster for vessels up to ~5 000 gt where space at the stern is limited and budget favours a 50 kW solution. Avoid if: the vessel requires high thrust (>10 kN), operates in extreme weather, or prefers electric drive without hydraulic infrastructure.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
HRP-TT-75 bow
unverified
· 75.0 kW
· tunnel thruster
Power (kW)
75
Thrust (kN)
9.0
Diameter (mm)
560
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (≈0.12 kN/kW) for its size
- Compact tunnel geometry fits within standard bow sections of medium‑size vessels
- Robust stainless‑steel propeller and housing provide good corrosion resistance in seawater
- Low vibration and noise compared with external azimuth units
- Straightforward installation using existing hull openings
Weaknesses
- Maximum thrust (9 kN) may be insufficient for large tankers or high‑wind berthing scenarios
- Fixed‑pitch propeller limits efficiency when operating far from design point
- Access for routine inspection requires removal of the tunnel cover, often needing dry‑dock time
- Noise and cavitation can increase at higher RPMs, affecting crew comfort in small vessels
Typical Vessels:
Coastal cargo shipsOffshore supply vesselsFerries (up to ~5 000 gt)Workboats and tugs with modest displacement
Decision Guide: Choose if: you need a reliable, compact bow thruster for vessels up to about 5 000 gt that operate mainly in ports, harbours or offshore terminals where space is limited and corrosion resistance is critical. Avoid if: the vessel requires higher thrust levels (e.g., large tankers, cruise ships) or expects frequent variable‑speed operation where a controllable‑pitch azimuth thruster would be more efficient.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HRP-TT-75 stern
unverified
· 75.0 kW
· tunnel thruster
Power (kW)
75
Thrust (kN)
9.0
Diameter (mm)
560
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (≈9 kN at only 75 kW)
- Compact footprint fits into limited hull space, especially aft installations
- Integrated motor design reduces vibration and simplifies alignment
- Low power consumption compared with larger thrusters of similar thrust
- Standardised mounting interface speeds up installation and replacement
Weaknesses
- Maximum thrust may be insufficient for large vessels or high‑speed DP operations
- Cavitation risk increases at higher RPMs, limiting efficiency in very shallow water
- Maintenance access can be restricted by the tunnel geometry on some hull forms
- Noise and vibration levels are higher than those of newer ducted‑propeller designs with advanced blade shaping
- Limited availability of spare parts outside Europe may affect lead times
Typical Vessels:
Offshore supply vessel (OSV)Ferry / passenger craft up to 150 m LOAWorkboat and utility vesselSmall container feeder or coastal traderCruise ship tender
Decision Guide: Choose if you need a moderate‑power stern thruster for vessels under ~200 m length where space is at a premium and power budget is limited. It is well suited to offshore support ships, ferries and workboats that require reliable low‑speed maneuverability or DP assistance without the cost of larger units. Avoid if your vessel requires high thrust (>12 kN), operates in very shallow water with high cavitation risk, or demands the lowest possible acoustic signature.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HRP-TT-100 bow
unverified
· 100.0 kW
· Tunnel bow thruster
Power (kW)
100
Thrust (kN)
12.0
Diameter (mm)
580
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (12 kN at 100 kW) gives strong low‑speed maneuverability.
- Compact tunnel footprint fits vessels with limited bow space.
- Holland Roer’s hydraulic drive is known for reliability and low maintenance intervals.
- Low acoustic and vibration signature, beneficial in noise‑sensitive ports.
Weaknesses
- Fixed installation adds hull resistance when the thruster is not in use.
- Requires a dedicated hydraulic power unit, increasing system complexity and space requirements.
- Maximum thrust of 12 kN may be insufficient for larger vessels or high‑wind conditions.
- Potential cavitation if tunnel geometry is not optimally matched to propeller speed.
Typical Vessels:
Handymax bulk carrierSmall to medium tankerOffshore supply vesselCruise ship feederContainer feeder
Decision Guide: Choose if the vessel needs strong bow‑side thrust for port entry/exit, has space for a fixed tunnel unit, and operates in confined waterways where low acoustic output is valued. Avoid if higher thrust (>15 kN) or retractable/azimuth thrusters are required, or if hull form cannot accommodate a permanent tunnel.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HRP-TT-100 stern
unverified
· 100.0 kW
· tunnel thruster
Power (kW)
100
Thrust (kN)
12.0
Diameter (mm)
580
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Compact 580 mm diameter fits well in limited hull spaces
- High hydraulic efficiency typical of HRP designs, reducing fuel penalty
- Robust stainless‑steel duct and propeller for long service intervals
- Integrated thrust bearing reduces vibration and noise
- Standard 100 kW rating matches many mid‑size vessel DP‑assist needs
Weaknesses
- Maximum thrust of 12 kN may be insufficient for very large vessels or strong currents
- Installation requires precise alignment of the tunnel duct in the hull structure
- Power demand (≈100 kW) can increase overall ship electrical load
- Limited to stern applications; not a dual‑direction unit
- Spare parts availability depends on regional HRP dealer network
Typical Vessels:
Container ships (up to ~8,000 TEU)Bulk carriers (handy‑size to panamax)Product tankersCruise vesselsOffshore supply & platform support vessels
Decision Guide: Choose if you need a reliable, compact stern thruster delivering ~12 kN thrust for vessels in the 5‑15 kt speed range and have space for a 580 mm tunnel. Avoid if higher thrust (>15 kN) or dual‑direction capability is required, or if hull modifications to accommodate the duct are prohibitive.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
HRP-TT-150 bow
unverified
· 150.0 kW
· tunnel thruster
Power (kW)
150
Thrust (kN)
18.0
Diameter (mm)
620
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (18 kN from 150 kW) gives strong lateral force for vessels up to medium size.
- Relatively compact duct diameter (620 mm) fits into limited hull space while still providing adequate flow.
- Robust Holland Roer design with proven bearing and seal arrangements reduces maintenance intervals.
- Integrated thrust control system compatible with most bridge‑integrated maneuvering packages.
Weaknesses
- Fixed bow installation limits flexibility; not suitable for vessels requiring both bow and stern thrusters of the same size.
- Power demand (150 kW) may require dedicated generator capacity on smaller ships.
- Potential for cavitation if operated at high RPM in shallow water, requiring careful propeller selection.
- Standard duct length may be insufficient for very deep‑draft vessels needing higher thrust without increasing power.
Typical Vessels:
Coastal tankerHandymax bulk carrierFeeder container shipOffshore supply vessel
Decision Guide: Choose if: you need a reliable bow thruster delivering >15 kN thrust on vessels up to ~30,000 gt where hull space for a 620 mm duct is available and you have sufficient generator capacity. Avoid if: the vessel requires both bow and stern thrusters of identical size, operates primarily in very shallow water where cavitation risk is high, or power budget is limited.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HRP-TT-150 stern
unverified
· 150.0 kW
· Tunnel thruster
Power (kW)
150
Thrust (kN)
18.0
Diameter (mm)
620
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (18 kN at 150 kW)
- Robust bronze propeller with stainless‑steel shaft for corrosion resistance
- Optimised blade geometry reduces cavitation and noise at typical operating speeds
- Compact tunnel size (620 mm) eases installation in medium‑size vessels
- Integrated sealing system minimises water ingress and maintenance intervals
Weaknesses
- Single unit provides no redundancy; failure eliminates lateral thrust capability
- Noise and vibration increase noticeably at full power, which may affect crew comfort
- Installation requires hull penetration and structural reinforcement of the tunnel area
- Performance degrades in heavy sea states or when operating near the vessel’s draft limit
- Tunnel lining wear demands periodic inspection and possible refurbishment
Typical Vessels:
Offshore supply vesselFerryWorkboat / Utility vesselSmall container ship (up to ~30 k TEU)Bulk carrier (up to ~20,000 dwt)
Decision Guide: Choose if you need a compact, high‑thrust stern thruster for vessels up to 150 kW power and can accommodate a tunnel installation; ideal for DP‑assist or tight‑port maneuvering. Avoid if the vessel requires redundant thrust units, higher thrust levels (>25 kN), or has limited hull space for a tunnel.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
HRP-TT-200 bow
unverified
· 200.0 kW
· tunnel thruster
Power (kW)
200
Thrust (kN)
24.0
Diameter (mm)
660
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (24 kN) relative to modest power rating (200 kW)
- Robust tunnel housing protects the propeller from debris and grounding impacts
- Compact installation footprint suitable for vessels with limited bow space
- Proven Dutch engineering reputation for reliability and low maintenance
Weaknesses
- Tunnel geometry adds resistance, reducing overall thrust‑to‑power efficiency compared with azimuth or pump‑jet thrusters
- Installation requires a sizable hull opening, affecting structural integrity if not properly reinforced
- Limited suitability for very shallow‑draft vessels where duct depth is constrained
- Fixed 360° rotation; no vectoring capability beyond the tunnel axis
Typical Vessels:
Product Tanker (up to ~30 000 dwt)Container FeederOffshore Supply VesselCruise Ship (mid‑size)Ferry
Decision Guide: Choose if: you need reliable bow thrust for medium‑sized vessels, have sufficient hull depth for a tunnel duct, and value durability in harsh port environments. Avoid if: the vessel operates in extremely shallow water, requires maximum thrust efficiency per kW, or needs full 360° vectoring without structural modifications.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HRP-TT-200 stern
unverified
· 200.0 kW
· electric tunnel thruster
Power (kW)
200
Thrust (kN)
24.0
Diameter (mm)
660
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (24 kN at 200 kW) for strong manoeuvring capability
- Compact 660 mm duct size fits medium‑sized hull openings without excessive structural modification
- Robust, corrosion‑resistant alloy housing suitable for harsh marine environments
- Direct‑drive electric motor reduces vibration and maintenance compared with hydraulic units
- Standardised mounting kit simplifies installation on new builds or retrofits
Weaknesses
- Designed only for stern installation; not interchangeable with bow locations
- Power demand (200 kW) may be significant for vessels with limited auxiliary generation capacity
- Potential cavitation at high RPM in shallow water, requiring careful propeller pitch selection
- Requires dedicated cooling and ventilation space within the hull tunnel
- Duct opening reduces internal cargo or equipment volume compared with smaller thrusters
Typical Vessels:
Handymax bulk carrierProduct tanker (up to 30 000 dwt)Offshore supply vesselCruise ship tenderContainer feeder
Decision Guide: Choose if: you need a reliable, high‑thrust stern thruster for vessels up to ~30 000 dwt that can accommodate a 660 mm tunnel and have sufficient auxiliary power. Avoid if: the vessel has limited space for a large duct, operates primarily on low‑power auxiliaries, or requires a bow thruster configuration.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
HRP-TT-250 bow
unverified
· 250.0 kW
· tunnel thruster
Power (kW)
250
Thrust (kN)
30.0
Diameter (mm)
700
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (30 kN at 250 kW) for its size
- Compact 700 mm tunnel fits vessels with limited hull space
- Proven Dutch design with low vibration and easy access for maintenance
- Integrated duct liner reduces cavitation and improves efficiency
Weaknesses
- Installation requires hull penetration, adding structural complexity
- Maximum thrust may be insufficient for very large or high‑draft vessels
- Potential for increased noise and vibration at full power compared with azimuth units
- Limited to shallow‑to‑moderate draft ships due to tunnel depth constraints
Typical Vessels:
Product Tanker (5 000–15 000 DWT)Container FeederOffshore Supply VesselCruise Ship (mid‑size)Ro‑Ro Ferry
Decision Guide: Choose if you need a reliable, high‑thrust bow thruster for vessels up to ~15 000 DWT with limited hull space and prefer a proven Dutch manufacturer. Avoid if the vessel requires thrust above 35 kN, operates in very deep draft conditions, or demands an azimuth unit for 360° thrust vectoring.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HRP-TT-250 stern
unverified
· 250.0 kW
· tunnel thruster
Power (kW)
250
Thrust (kN)
30.0
Diameter (mm)
700
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (30 kN at 250 kW) for its size class
- Compact 700 mm tunnel diameter fits in moderate hull openings
- Robust, low‑maintenance construction typical of Holland Roer designs
- Direct thrust line simplifies integration with ship’s control system
Weaknesses
- Fixed‑direction thrust limits maneuverability compared with azimuth units
- Potential for cavitation and noise at high RPMs
- Requires significant hull penetration and structural reinforcement
- Less effective in very shallow water due to duct draft
Typical Vessels:
Offshore supply vesselCruise shipContainer ship (mid‑size)LNG carrier (medium size)Ferry
Decision Guide: Choose if you need a reliable, high‑thrust stern thruster for vessels of up to medium size where space is limited and azimuth units are not required. Avoid if the vessel demands full 360° thrust vectoring, ultra‑quiet operation, or has severe weight/space constraints that favour smaller duct sizes.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HRP-TT-300 bow
unverified
· 300.0 kW
· tunnel thruster
Power (kW)
300
Thrust (kN)
36.0
Diameter (mm)
740
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust-to-power ratio (36 kN at 300 kW) for effective sideways thrust
- Compact bow installation fits within limited hull space
- Low vibration and noise due to enclosed tunnel design
- Proven reliability of Holland Roer propeller blades
- Suitable for vessels requiring precise port handling
Weaknesses
- Tunnel depth may limit use on very shallow‑draft ships
- Potential cavitation at high RPMs if not properly sized for hull form
- Maintenance access can be restricted compared with azimuth thrusters
- Fixed thrust direction; no 360° rotation capability
- Power demand of 300 kW adds to overall ship electrical load
Typical Vessels:
Container ships (up to ~5,000 TEU)Bulk carriers (10–30 kt)Tankers (product or chemical up to ~30 kt)Cruise vesselsOffshore supply and support vessels
Decision Guide: Choose if the vessel needs a powerful, compact bow thruster for tight port maneuvers, dynamic positioning assistance, or emergency stopping, and the hull can accommodate a tunnel of ~740 mm diameter. Avoid if the ship operates in extremely shallow water, requires 360° thrust vectoring, or prefers an azimuth pod for higher maneuverability.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
HRP-TT-300 stern
unverified
· 300.0 kW
· ducted tunnel thruster
Power (kW)
300
Thrust (kN)
36.0
Diameter (mm)
740
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (36 kN at 300 kW) improves docking performance
- Large 740 mm diameter duct offers efficient water flow and reduced slip
- Robust steel construction typical of Holland Roer designs ensures long service life
- Low vibration and noise levels compared with open propeller thrusters
- Standardized mounting dimensions simplify integration into new builds
Weaknesses
- Large physical footprint limits installation on vessels with restricted stern space
- Higher power consumption than azimuth pod or water‑jet alternatives for equivalent maneuverability
- Typical tunnel‑thruster cavitation risk at high RPMs, especially in shallow water
- Reverse thrust efficiency is lower than forward thrust due to duct geometry
- Access for routine inspection can be constrained on stern‑mounted units
Typical Vessels:
ContainerBulk CarrierGeneral CargoRo‑RoOffshore Supply Vessel
Decision Guide: Choose if: you need strong low‑speed thrust for port manoeuvring, have sufficient stern space for a 740 mm duct, and prefer a proven, low‑maintenance tunnel design. Avoid if: hull form restricts large thruster installation, you require 360° vectoring or lower power draw, or cavitation risk in very shallow drafts is a primary concern.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HRP-TT-400 bow
unverified
· 400.0 kW
· tunnel thruster
Power (kW)
400
Thrust (kN)
48.0
Diameter (mm)
820
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust (48 kN) for its power rating, improving low‑speed maneuverability
- Relatively compact tunnel diameter (820 mm) fits into moderate‑size hulls
- Robust Holland Roer design with proven marine‑grade bearings and seals
- Integrated motor‑propeller unit simplifies installation and alignment
Weaknesses
- Fixed‑direction thrust; cannot rotate like an azimuth pod
- Tunnel geometry may be susceptible to cavitation in very shallow water
- Limited redundancy – a single point of failure for bow maneuvering
- Requires sufficient hull space forward of the bow for tunnel housing
Typical Vessels:
Offshore supply vesselContainer feederGeneral cargo ship (up to ~30 000 GT)Cruise ship (mid‑size)Ferry
Decision Guide: Choose if: you need strong bow thrust for a vessel of up to medium size, have adequate forward hull space for an 820 mm tunnel, and prefer a proven fixed‑direction thruster for docking or low‑class DP. Avoid if: you require 360° thrust vectoring, operate in extremely shallow drafts where cavitation risk is high, or need built‑in redundancy for critical maneuvering.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
HRP-TT-400 stern
unverified
· 400.0 kW
· tunnel thruster
Power (kW)
400
Thrust (kN)
48.0
Diameter (mm)
820
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (48 kN @ 400 kW) for a compact installation
- Robust ducted‑propeller construction with proven reliability in harsh marine environments
- Relatively low vibration and noise compared with open‑propeller designs
- Straightforward maintenance access through the tunnel housing
Weaknesses
- Limited to fixed‑direction thrust; cannot provide 360° vectoring like azimuth pods
- Higher cavitation risk at full load if not matched with proper hull form
- Installation requires a sizable tunnel aperture (≈820 mm diameter) and hull reinforcement
- Less efficient for high‑speed maneuvering or dynamic positioning compared with electric pod systems
Typical Vessels:
Container shipsBulk carriersProduct tankersCruise linersOffshore supply vesselsFerries
Certifications:
DNV GL Type ApprovalABS Classification approval
Decision Guide: Choose if you need a cost‑effective, high‑thrust solution for stern maneuvering on medium‑size cargo or passenger ships where space is limited and full DP capability is not required. Avoid if the vessel requires omnidirectional thrust control, ultra‑low noise operation, or operates primarily at high speeds where pod thrusters are more efficient.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HRP-TT-500 bow
unverified
· 500.0 kW
· ducted tunnel bow thruster
Power (kW)
500
Thrust (kN)
60.0
Diameter (mm)
900
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (60 kN) relative to power consumption, enabling rapid lateral movement in port.
- Compact installation footprint fits within standard hull openings without major structural modifications.
- Proven Holland Roer design with a long service record and low vibration levels.
- Straightforward integration with existing ship control systems and DP packages.
Weaknesses
- Limited azimuth capability – thrust is fixed to the tunnel axis, reducing maneuverability compared with rotating thrusters.
- Potential for cavitation if inlet flow is not properly managed or if operated at high RPM in shallow water.
- Maintenance access can be challenging due to its location within the hull and the need to remove surrounding structure.
- Noise generation may be higher than that of newer low‑speed, oil‑free designs.
Typical Vessels:
Container shipsCrude oil tankersBulk carriersOffshore support vesselsCruise liners
Decision Guide: Choose if the vessel requires strong lateral thrust for docking, has sufficient hull depth to accommodate a tunnel duct, and budget constraints favor a proven, cost‑effective solution. Avoid if full 360° thrust vectoring is needed, draft is very shallow, or noise/cavitation concerns outweigh the benefits of higher thrust.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HRP-TT-500 stern
unverified
· 500.0 kW
· tunnel thruster
Power (kW)
500
Thrust (kN)
60.0
Diameter (mm)
900
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (60 kN) relative to installed power (500 kW)
- Large 900 mm tunnel reduces cavitation risk and improves hydraulic efficiency
- Robust steel construction typical of Holland Roer products, offering long service life
- Compact stern‑mount layout fits vessels with limited bow space
Weaknesses
- Relatively high power consumption compared with newer ducted or azimuth thrusters delivering similar thrust
- Installation requires a sizable hull opening (≈0.9 m), affecting structural design
- Maintenance access can be constrained in tight stern compartments
- Noise and vibration levels may be higher than low‑frequency azimuth units
Typical Vessels:
Container ships (up to ~30,000 DWT)Medium tankersBulk carriersOffshore supply vesselsCruise liners (mid‑size)
Decision Guide: Choose if the vessel needs a proven, high‑thrust stern thruster and has sufficient hull space for a 0.9 m tunnel; especially suitable for ships requiring reliable low‑speed manoeuvring or DP support. Avoid if noise limits are critical, if you prefer lower power consumption solutions, or when azimuth thrusters provide better all‑direction thrust control.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HRP-TT-600 bow
unverified
· 600.0 kW
· tunnel thruster
Power (kW)
600
Thrust (kN)
72.0
Diameter (mm)
980
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (72 kN at 600 kW) gives strong manoeuvring capability.
- Compact 980 mm diameter fits vessels with limited hull space.
- Robust stainless‑steel duct and propeller design provides long service life in harsh marine environments.
- Lower acoustic signature than some azimuth units, beneficial for noise‑sensitive operations.
- Standard integration with common ship control systems; optional variable‑speed drive available.
Weaknesses
- 600 kW power demand increases fuel consumption and requires substantial electrical supply capacity.
- Installation involves significant hull penetration and structural reinforcement.
- Fixed thrust direction limits flexibility compared with azimuth thrusters for dynamic positioning.
- Maintenance access can be restricted, especially on vessels with shallow bow sections.
- Initial procurement cost is higher than smaller‑capacity tunnel units.
Typical Vessels:
Container shipCruise linerOffshore supply vesselLNG carrierRo‑Ro ferry
Decision Guide: Choose if you need a powerful, space‑efficient bow thruster for large ocean‑going vessels and can accommodate the hull modifications and power supply. Avoid if you require full 360° thrust vectoring, have very limited power generation capacity, or prefer a lower‑cost solution with less structural work.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
HRP-TT-600 stern
unverified
· 600.0 kW
· tunnel thruster
Power (kW)
600
Thrust (kN)
72.0
Diameter (mm)
980
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (72 kN at 600 kW) gives excellent manoeuvring capability.
- Compact 980 mm duct diameter fits in vessels with limited stern space.
- Robust steel housing and proven Holland Roer design for long service life.
- Integrated water‑cooling system reduces overheating during prolonged use.
Weaknesses
- Relatively high power demand may increase fuel consumption on low‑speed operations.
- Installation requires a sizable tunnel duct; not suitable for vessels with very shallow stern drafts.
- Maintenance of bearings and seals can be labour‑intensive compared to azimuth pods.
- Noise and vibration levels are higher than some newer electric or pod‑type thrusters.
Typical Vessels:
Offshore supply vesselContainer ship (up to 5 000 gt)Bulk carrier (mid‑size)Cruise ferryRo‑Ro vessel
Decision Guide: Choose if you need a proven, high‑thrust stern thruster for vessels up to medium size where space allows a ~1 m duct and you value durability over the latest low‑noise electric solutions. Avoid if vessel draft is extremely shallow, power budget is tight, or you prefer an azimuth pod or electric thruster with lower acoustic signature.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HRP-TT-750 bow
unverified
· 750.0 kW
· tunnel thruster
Power (kW)
750
Thrust (kN)
90.0
Diameter (mm)
1100
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (≈90 kN at 750 kW) suitable for very large ships
- Robust tunnel construction with corrosion‑resistant lining, low maintenance
- Integrated variable‑frequency drive option for fine thrust control
- Compact installation envelope – fits within a 1.1 m hull opening
- Proven track record of Holland Roer’s propeller design expertise
Weaknesses
- Fixed azimuth – cannot rotate like a pod or azipod, limiting lateral thrust direction
- Relatively high power demand may require dedicated generator capacity
- Installation requires precise alignment and sealing of the tunnel duct
- Noise and vibration can be higher than in ducted propeller‑type thrusters if not properly isolated
Typical Vessels:
Very Large Crude Carrier (VLCC)Ultra‑Large Container Ship (ULCS)Cruise shipOffshore supply vesselRo‑Ro ferry
Certifications:
IMO Type Approval (SOLAS)DNV GL Class approvalABS class approval
Decision Guide: Choose if you need a reliable, high‑thrust bow thruster for vessels >150 m LOA where space for a larger duct is available and azimuth capability is not required. Avoid if the vessel requires 360° thrust vectoring, ultra‑low noise operation, or has severe power‑generation constraints.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HRP-TT-750 stern
unverified
· 750.0 kW
· tunnel thruster
Power (kW)
750
Thrust (kN)
90.0
Diameter (mm)
1100
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust output (≈90 kN) for a 750 kW unit, enabling strong lateral forces during berthing and DP operations.
- Large 1100 mm tunnel diameter reduces cavitation risk and improves efficiency at high power levels.
- Stern‑mount configuration provides additional maneuvering control when combined with bow thrusters, useful for dynamic positioning.
- Robust Holland Roer construction known for long service life in harsh marine environments.
Weaknesses
- Large tunnel cross‑section occupies significant hull volume, potentially affecting structural layout and cargo space.
- High power demand (750 kW) increases fuel consumption of the ship’s auxiliary system.
- Installation requires substantial hull penetration and reinforcement, raising retrofit cost and time.
- Noise and vibration levels can be higher than smaller thrusters if not properly isolated.
Typical Vessels:
Container ships (>8 000 TEU)Cruise linersLNG carriersLarge tankersOffshore supply vessels with DP capability
Decision Guide: Choose if: the vessel requires high‑power stern thrust for tight port manoeuvring, dynamic positioning or emergency stop; space and hull strength are sufficient to accommodate a 1.1 m tunnel. Avoid if: the ship has limited hull volume, low auxiliary power availability, or cost‑sensitive projects where a smaller thruster would meet requirements.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HRP-TT-800 bow
unverified
· 800.0 kW
· tunnel bow thruster
Power (kW)
800
Thrust (kN)
96.0
Diameter (mm)
1140
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (96 kN at 800 kW) improves port handling performance.
- Large 1,140 mm duct reduces cavitation and noise, extending service life.
- Robust stainless‑steel housing tolerates harsh marine environments and high‑impact loads.
- Integrated control electronics allow smooth variable‑speed operation and easy integration with ship automation systems.
- Proven track record on a range of large commercial vessels, offering reliable long‑term performance.
Weaknesses
- Physical size (1.14 m duct) requires substantial hull opening; not suitable for vessels with limited bow space.
- Higher initial capital cost compared with smaller or simpler thruster designs.
- Weight and installation complexity can increase dry‑dock time during retrofit projects.
- Power demand of 800 kW may necessitate dedicated generator capacity on smaller ships.
Typical Vessels:
Container shipBulk carrierCruise linerLNG/LPG carrierOffshore supply vessel
Decision Guide: Choose the HRP‑TT‑800 when a large vessel (>150 m LOA) needs strong bow thrust for tight port manoeuvring, dynamic positioning assistance, or emergency maneuverability and can accommodate a 1.14 m tunnel opening. Avoid if the ship’s bow space is limited, power plant cannot spare 800 kW, or budget constraints favour a smaller, lower‑cost thruster.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HRP-TT-800 stern
unverified
· 800.0 kW
· tunnel thruster
Power (kW)
800
Thrust (kN)
96.0
Diameter (mm)
1140
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (≈96 kN) for its power rating, enabling effective stern assistance on large vessels
- Compact tunnel layout fits within standard hull openings without protruding appendages
- Robust Holland Roer blade design provides good cavitation resistance and low vibration
- Integrated water‑cooling system reduces overheating risk during prolonged use
Weaknesses
- Large duct diameter (≈1.14 m) can limit placement options in vessels with narrow stern sections
- High power demand (800 kW) increases fuel consumption when used frequently
- Maintenance access to the internal impeller requires removal of the tunnel cover, which can be time‑consuming
- Potential for increased noise and vibration compared with azimuth pod thrusters at full power
Typical Vessels:
Container shipBulk carrierCruise linerOffshore supply vesselRo‑Ro ferry
Decision Guide: Choose if: you need a high‑thrust stern thruster for vessels >150 m LOA where hull space allows a ~1.14 m tunnel and you value proven Holland Roer reliability. Avoid if: the vessel has limited stern clearance, you prefer azimuth or pod‑type maneuvering devices, or you must minimise power consumption during frequent thruster use.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
HRP-TT-1000 bow
unverified
· 1000.0 kW
· high‑power tunnel thruster
Power (kW)
1000
Thrust (kN)
120.0
Diameter (mm)
1300
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (≈120 kN) for a 1000 kW unit, giving strong low‑speed manoeuvring capability
- Relatively compact duct diameter (1300 mm) allowing installation on vessels with limited hull space
- Robust steel tunnel construction suited to heavy‑duty service and harsh marine environments
- Optimised blade geometry for reduced cavitation and lower noise levels compared with older designs
- Integrated control interface compatible with most DP and ship‑handling systems
Weaknesses
- High power rating leads to significant electrical demand and associated installation costs
- Large thrust output may be over‑spec for smaller vessels, resulting in unnecessary fuel/energy consumption
- Maintenance access can be limited inside the tunnel, requiring dry‑dock periods for major work
- Potentially higher acoustic signature than low‑power thrusters, which may be a concern for noise‑sensitive operations
- Initial procurement cost is typically above average for comparable thrust levels
Typical Vessels:
Very Large Crude Carrier (VLCC)Ultra Large Container Ship (ULCS)Cruise shipOffshore supply vesselLNG carrier
Decision Guide: Choose if: you need a high‑thrust bow thruster for a large vessel with limited hull space and require reliable DP or close‑quarter manoeuvring. Avoid if: the vessel’s power budget is tight, thrust requirements are modest, or installation/maintenance resources are constrained.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
HRP-TT-1000 stern
unverified
· 1000.0 kW
· tunnel thruster
Power (kW)
1000
Thrust (kN)
120.0
Diameter (mm)
1300
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high power rating (1 000 kW) suitable for large vessels requiring strong lateral thrust
- High static thrust output (120 kN) improves docking and dynamic positioning performance
- Large propeller diameter (1.3 m) provides good hydraulic efficiency at low speeds
- Robust construction typical of Holland Roer designs, known for durability in harsh marine environments
- Designed specifically for stern installation, allowing better flow around the hull compared with bow‑only solutions
Weaknesses
- Large tunnel cross‑section reduces available hull volume and may affect structural integrity if not properly reinforced
- High power consumption increases fuel use and may require upgraded electrical or hydraulic supply systems
- Installation and alignment are complex, often requiring dry‑dock periods and specialised tooling
- Maintenance of large bearings and seals can be more demanding than smaller thrusters
- Potential for cavitation at high load if not matched with appropriate hull form and flow conditions
Typical Vessels:
Very Large Crude Carrier (VLCC)Ultra‑Large Container Vessel (ULCV)Cruise ShipOffshore Supply Vessel (OSV)Floating Production Storage & Offloading unit (FPSO)
Decision Guide: Choose if: you need a high‑thrust stern thruster for vessels >200 m LOA, have sufficient hull space for a 1.3 m tunnel, and require strong maneuvering capability for DP or tight port operations. Avoid if: vessel size limits tunnel installation, power budget is constrained, or a lower‑power bow thruster suite can meet the manoeuvring requirements.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HRP-TT-1200 bow
unverified
· 1200.0 kW
· tunnel bow thruster
Power (kW)
1200
Thrust (kN)
144.0
Diameter (mm)
1460
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (144 kN) suitable for large vessels and tight port operations
- Robust tunnel design provides good protection against debris and hull fouling
- Integrated with Holland Roer’s control system for smooth, low‑noise operation
- Proven reliability on a range of deep‑draft ships in harsh environments
Weaknesses
- High power demand (1 200 kW) leads to significant fuel consumption and electrical load
- Large tunnel diameter requires substantial hull penetration and structural reinforcement
- Potential for cavitation at high thrust settings, requiring careful monitoring
- Maintenance access can be limited due to the size of the tunnel housing
Typical Vessels:
Container shipCrude oil tankerLNG carrierCruise linerOffshore supply vessel
Decision Guide: Choose if you need a high‑thrust bow thruster for vessels over 150 m LOA operating in confined ports or requiring tight station‑keeping. Avoid on smaller ships where the power and tunnel size would be disproportionate to manoeuvring needs.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HRP-TT-1200 stern
unverified
· 1200.0 kW
· high‑power tunnel thruster
Power (kW)
1200
Thrust (kN)
144.0
Diameter (mm)
1460
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (144 kN) for its size, providing strong bow‑/stern‑side force in tight berths
- Robust Holland Roer design with proven long‑term reliability and low maintenance intervals
- Modular construction allows relatively straightforward installation and replacement
- Integrated water‑cooling system suited for continuous high‑power operation
Weaknesses
- Large duct diameter (1.46 m) may require significant hull penetration and structural reinforcement
- High power rating (1200 kW) leads to notable fuel consumption when used extensively
- Spare parts and service expertise are concentrated in major ship‑yards, potentially limiting rapid repairs in remote locations
- Weight and size can limit suitability for smaller vessels or those with restricted hull space
Typical Vessels:
Container ships (10 000–15 000 TEU)Bulk carriers (>150 m LOA)Tankers (LR2, LR1)Cruise shipsOffshore supply and support vessels
Decision Guide: Choose if: you need a high‑thrust stern thruster for large vessels that require strong lateral control during docking or emergency maneuvers, and the hull can accommodate a 1.46 m duct. Avoid if: vessel size or hull geometry cannot support the required structural modifications, or operating in regions where Holland Roer service networks are scarce.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HRP-TT-1500 bow
unverified
· 1500.0 kW
· tunnel thruster
Power (kW)
1500
Thrust (kN)
180.0
Diameter (mm)
1700
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust‑to‑power ratio (180 kN at 1500 kW) suitable for DP and tight port maneuvers
- Compact duct diameter (1.7 m) fits in limited hull space while still providing strong flow
- Proven Dutch design with robust bearing and seal systems for long service intervals
- Low vibration and noise levels compared with external azimuth units
- Integrated control electronics compatible with most ship‑board DP consoles
Weaknesses
- Large hull penetration required; installation is complex and may affect structural integrity
- Higher power consumption than smaller thrusters, impacting overall fuel efficiency
- Maintenance of internal bearings and seals can be demanding on dry‑dock schedules
- Potential for cavitation at very high thrust settings in shallow water
- Limited availability of spare parts outside Europe, leading to longer lead times
Typical Vessels:
Container ships (20 000–30 000 dwt)Crude oil tankers and product carriersLNG/LPG carriersOffshore supply vessels with DP‑1/DP‑2 capabilityCruise liners
Decision Guide: Choose if: you need a high‑thrust bow thruster for vessels >20 000 dwt, dynamic positioning or tight port entry where strong low‑speed maneuverability is critical. Avoid if: the vessel size and power budget are modest, hull space cannot accommodate a 1.7 m duct, or maintenance facilities are limited to short‑interval servicing.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HRP-TT-1500 stern
unverified
· 1500.0 kW
· tunnel thruster
Power (kW)
1500
Thrust (kN)
180.0
Diameter (mm)
1700
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust output (180 kN) relative to power rating, suitable for DP‑class vessels
- Robust ducted design reduces blade wear and provides good protection in debris‑laden waters
- Compact footprint compared with azimuth pods of similar power, saving hull space
- Proven Holland Roer Propeller engineering reputation for reliability and low maintenance
Weaknesses
- Large diameter (1.7 m) duct requires significant hull cut‑out, limiting installation on smaller ships
- High electrical demand (1500 kW) may exceed the power budget of vessels with limited generator capacity
- Potential for cavitation at high RPMs if not matched to proper inflow conditions
- Weight and structural reinforcement requirements can increase overall vessel weight
Typical Vessels:
Container ships (≥8 000 gt)Cruise linersOffshore supply vesselsLNG carriersDP‑class tankers
Decision Guide: Choose if: you need a high‑thrust stern thruster for dynamic positioning or tight port manoeuvring on large vessels and have sufficient hull space and power generation capacity. Avoid if: vessel size, weight limits, or electrical supply cannot accommodate a 1500 kW unit, or if a more compact azimuth pod would better suit the operational profile.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
HRP-TT-2000 bow
unverified
· 2000.0 kW
· high‑efficiency tunnel thruster
Power (kW)
2000
Thrust (kN)
240.0
Diameter (mm)
2100
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust‑to‑power ratio (≈240 kN @ 2000 kW)
- Compact tunnel housing reduces hull penetration and protects the propeller from damage
- Robust steel construction with proven cavitation resistance for long service life
- Integrated cooling system allows continuous operation at high power levels
- Standard ABS/DNV class approval simplifies certification on new builds
Weaknesses
- Large tunnel diameter (2.1 m) requires significant hull space and structural reinforcement
- High electrical/mechanical power demand increases installation cost and auxiliary plant sizing
- Installation is complex; precise alignment of the tunnel and shaft is critical
- Higher upfront cost compared with smaller conventional bow thrusters or azimuth units
- Noise and vibration can be higher than low‑speed azimuth thrusters, requiring additional mitigation
Typical Vessels:
Cruise shipLarge container vesselLNG carrierFPSO / offshore production unitVery large bulk carrier
Certifications:
ABS Type ApprovalDNV GL Class Notation
Decision Guide: Choose if: the ship requires high bow thrust for safe docking or DP in confined ports, hull form can accommodate a 2.1 m tunnel, and sufficient power plant capacity is available. Avoid if: vessel size is limited, budget constraints preclude a large‑diameter thruster, or an azimuth pod offers better all‑directional thrust for the operational profile.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HRP-TT-2000 stern
unverified
· 2000.0 kW
· tunnel thruster
Power (kW)
2000
Thrust (kN)
240.0
Diameter (mm)
2100
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (240 kN) at 2000 kW enables rapid stern‑side manoeuvring of mega‑vessels.
- Compact tunnel geometry reduces hull penetration and preserves structural integrity.
- Robust stainless‑steel housing offers long service life in harsh marine environments.
- Integrated control electronics compatible with most DP and bridge systems.
- Proven Dutch engineering reputation for reliability and low cavitation.
Weaknesses
- High power demand (2 MW) increases fuel consumption and requires substantial electrical supply.
- Large tunnel diameter (2.1 m) occupies significant hull space, limiting installation on smaller ships.
- Installation may require reinforcement of the stern structure, adding to build cost.
- Maintenance access can be restricted in very tight aft compartments.
- Initial purchase price is higher than lower‑power alternatives.
Typical Vessels:
VLCC / Suezmax tankersUltra‑large container vessels (ULCV)LNG carriersLarge offshore supply vesselsCruise ships over 200 m LOA
Decision Guide: Choose if the vessel needs a high‑thrust stern thruster for DP operations, tight port manoeuvring or emergency backing on very large ships and you have sufficient power and space. Avoid if the ship is under 150 m LOA, has limited aft volume, or budget constraints make a lower‑power unit more appropriate.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HRP-TT-2500 bow
unverified
· 2500.0 kW
· Tunnel thruster
Power (kW)
2500
Thrust (kN)
300.0
Diameter (mm)
2500
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust‑to‑power ratio (≈0.12 kN/kW) suitable for DP‑class ships
- Compact tunnel layout fits within limited hull space while providing strong lateral force
- Robust steel construction and proven Holland Roer reliability record
- Available with both electric and hydraulic drive options for flexibility in integration
- Low acoustic signature compared with some azimuth pods, beneficial for passenger comfort
Weaknesses
- Requires a hull penetration that must be carefully reinforced to avoid stress concentrations
- Tunnel geometry can promote cavitation noise at high RPMs, especially in shallow water
- Maintenance access is limited; internal components may need dry‑dock periods for overhaul
- Less effective than azimuth thrusters for 360° thrust vectoring in tight berths
- Installation cost rises with larger diameters and associated structural modifications
Typical Vessels:
Very Large Crude Carrier (VLCC)Ultra‑Large Container Vessel (ULCV)Cruise shipOffshore supply vesselLNG carrier
Decision Guide: Choose the HRP‑TT‑2500 when a large vessel needs high bow thrust for dynamic positioning, tight port manoeuvring or emergency stopping and the hull can accommodate a tunnel installation. Avoid if the ship is small to medium size, if 360° thrust vectoring is required, or when maintenance windows are severely limited.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HRP-TT-2500 stern
unverified
· 2500.0 kW
· large-diameter tunnel thruster
Power (kW)
2500
Thrust (kN)
300.0
Diameter (mm)
2500
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (≈300 kN) suitable for ultra‑large ships and DP operations
- Large 2.5 m nozzle reduces cavitation and improves efficiency at low speeds
- Robust Holland Roer construction with proven service life in harsh marine environments
- Integrated stern placement aids rapid reverse thrust during docking and emergency maneuvers
Weaknesses
- Requires substantial hull opening (≈2.5 m) and structural reinforcement
- High power demand (2 500 kW) increases fuel consumption of auxiliary generators
- Installation and maintenance access can be limited in tight aft spaces
- Capital cost is higher than smaller thrusters; spare‑part inventory may be specialised
Typical Vessels:
VLCCULCV (Ultra Large Container Vessel)LNG carrierOffshore support vesselCruise ship
Decision Guide: Choose if the vessel requires very high thrust for dynamic positioning, tight‑port maneuvering or emergency stopping on ships larger than 150 000 gt. Avoid if hull space is limited, power generation capacity is modest, or a smaller thruster can meet the manoeuvring requirements.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HRP-TT-3000 bow
unverified
· 3000.0 kW
· ducted tunnel thruster
Power (kW)
3000
Thrust (kN)
360.0
Diameter (mm)
2900
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (360 kN) for its size, enabling rapid lateral movement in tight ports
- Robust Holland Roer construction with corrosion‑resistant duct and propeller blades
- Modular design allows relatively quick on‑site replacement of the propeller assembly
- Integrated control interface compatible with common ship automation systems
- Proven reliability on a range of ultra‑large commercial vessels
Weaknesses
- Large physical envelope (2.9 m diameter) limits installation to ships with sufficient hull space
- High power demand (3 MW) requires substantial electrical/hydraulic supply infrastructure
- Higher initial capital cost compared with lower‑power thrusters
- Maintenance access can be challenging in confined bow sections
- Noise and vibration levels must be managed on passenger vessels
Typical Vessels:
Very Large Crude Carrier (VLCC)Ultra‑Large Container Ship (ULCS)Panamax Bulk CarrierCruise ShipOffshore Supply Vessel
Certifications:
IMO Type ApprovalDNV Classification
Decision Guide: Choose if the vessel requires high lateral thrust for port entry, dynamic positioning or maneuvering in restricted waterways and has sufficient bow space and power supply. Avoid on smaller ships where the size, power consumption and cost outweigh the manoeuvring benefit.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HRP-TT-3000 stern
unverified
· 3000.0 kW
· ducted tunnel thruster
Power (kW)
3000
Thrust (kN)
360.0
Diameter (mm)
2900
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (360 kN) suitable for very large ships
- Compact tunnel layout fits in limited stern space while providing strong lateral force
- Ducted design reduces cavitation and improves thrust efficiency at low speeds
- Robust construction typical of Holland Roer products, offering long service intervals
Weaknesses
- High power demand (3 MW) increases fuel consumption during thruster use
- Large tunnel diameter (2.9 m) may limit installation on vessels with restricted hull geometry
- Maintenance of high‑power ducted units can be more complex and costly than smaller azimuth pods
- Noise and vibration levels are higher than low‑power alternatives, requiring additional mitigation
Typical Vessels:
Very Large Crude Carrier (VLCC)Ultra Large Container Vessel (ULCV)Cruise ShipOffshore Support Vessel (OSV) with DP2/3LNG Carrier
Decision Guide: Choose if the vessel requires >300 kN of lateral thrust for safe port entry, tight‑berth handling or high‑grade dynamic positioning and has sufficient stern space for a 2.9 m tunnel. Avoid on smaller ships where power consumption, installation envelope, or cost outweigh the need for such high thrust.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HRP-TT-3500 bow
unverified
· 3500.0 kW
· tunnel thruster
Power (kW)
3500
Thrust (kN)
420.0
Diameter (mm)
3300
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (420 kN) suitable for vessels >150 m LOA
- Compact tunnel layout fits within standard bow sections without external protrusion
- Robust steel housing and impeller design gives long service intervals
- Low acoustic signature compared with azimuth thrusters, beneficial for passenger comfort
Weaknesses
- Large diameter (3.3 m) limits installation on vessels with narrow bows
- High electrical power demand (3.5 MW) increases generator load and fuel consumption
- Potential cavitation at full‑load operation in shallow water
- Single‑unit design provides less redundancy than twin‑azimuth arrangements
Typical Vessels:
Very Large Crude Carrier (VLCC)Ultra Large Container Vessel (ULCV)LNG carrierCruise shipOffshore supply vessel
Decision Guide: Choose if: you need maximum bow thrust for a vessel >150 m, require a compact tunnel solution that does not affect hull lines, and have sufficient generator capacity. Avoid if: hull space is limited, power budget is tight, or redundancy through multiple thrusters is required.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
HRP-TT-3500 stern
unverified
· 3500.0 kW
· high‑power tunnel thruster
Power (kW)
3500
Thrust (kN)
420.0
Diameter (mm)
3300
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (≈420 kN) suitable for large vessels and DP operations
- Large 3300 mm tunnel diameter provides efficient water flow and reduced cavitation
- Integrated tunnel design minimises hull penetration and improves structural integrity
- Proven Holland Roer brand reputation for reliability in harsh marine environments
Weaknesses
- Requires a sizable hull opening and substantial structural reinforcement
- High electrical power demand (≈3500 kW) may limit use on vessels with limited generator capacity
- Installation space is considerable, restricting fit on smaller ships or retrofits with tight aft spaces
- Spare‑part logistics can be challenging for remote ports due to the size and specificity of the unit
Typical Vessels:
LNG carrierCruise shipOffshore supply vesselVery large crude carrier (VLCC)Container ship (>10,000 TEU)Bulk carrier (>200 kt)
Decision Guide: Choose if the vessel requires >400 kN of thrust for dynamic positioning, tight‑berth handling or high‑speed maneuvering and has sufficient aft space and power generation capacity. Avoid if hull modifications are prohibitive, power plant is limited, or a smaller, lower‑cost thruster meets the operational needs.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HRP-TT-4000 bow
unverified
· 4000.0 kW
· tunnel thruster
Power (kW)
4000
Thrust (kN)
480.0
Diameter (mm)
3700
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust‑to‑power ratio (480 kN at 4000 kW) for rapid bow response
- Robust steel tunnel construction with proven low‑cavitation blade geometry
- Modular design allows quick access to the propeller and motor for maintenance
- Integrated control electronics compatible with most DP and ship‑handling systems
- Long service life under heavy duty marine conditions
Weaknesses
- Large tunnel diameter (3.7 m) requires substantial hull penetration, limiting installation on smaller ships
- High electrical power demand increases onboard generator sizing and fuel consumption
- Heavy overall unit weight adds to vessel deadweight and may affect stability calculations
- Higher initial capital cost compared with conventional bow thrusters of similar power
- Installation and alignment are complex, requiring specialised shipyard facilities
Typical Vessels:
Container ships (>150 m LOA)Crude oil tankersBulk carriersLNG/LPG carriersCruise linersOffshore supply vessels with DP requirements
Certifications:
DNV
Decision Guide: Choose the HRP‑TT‑4000 when a vessel needs maximum bow thrust for tight port manoeuvring, dynamic positioning or emergency stopping and has sufficient hull space for a 3.7 m tunnel. Avoid it on smaller ships where tunnel size, weight or budget constraints make a conventional thruster or azimuth pod more appropriate.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HRP-TT-4000 stern
unverified
· 4000.0 kW
· tunnel thruster
Power (kW)
4000
Thrust (kN)
480.0
Diameter (mm)
3700
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (≈480 kN) suitable for large vessels and DP operations
- Robust, corrosion‑resistant ducting and propeller design for long service life
- Integrated nozzle reduces cavitation and improves thrust efficiency
- Modular construction simplifies installation and maintenance at the stern
Weaknesses
- Large physical envelope (≈3.7 m diameter) limits use on vessels with restricted hull space
- High power demand (4 MW) increases fuel consumption and electrical load
- Installation requires significant structural reinforcement of the stern
- Higher upfront cost compared to smaller or conventional tunnel thrusters
Typical Vessels:
Ultra‑large container shipsCrude oil tankersLNG carriersCruise linersOffshore supply vessels with DP capability
Decision Guide: Choose if: you need maximum stern thrust for a vessel >150 m LOA, require reliable DP or emergency maneuvering, and have sufficient hull space and power generation capacity. Avoid if: the ship’s design constraints limit duct size, power budget is tight, or a lower‑cost, lower‑thrust solution suffices.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HRP-TT-4500 bow
unverified
· 4500.0 kW
· Tunnel thruster
Power (kW)
4500
Thrust (kN)
540.0
Diameter (mm)
4100
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust output (≈540 kN) for its power rating, giving strong bow control on large vessels
- Robust Dutch engineering with proven reliability in harsh sea conditions
- Large duct diameter reduces cavitation and improves hydraulic efficiency
- Modular construction allows relatively quick installation and maintenance access
- Integrated cooling system (standard on HRP‑TT series) supports continuous high‑power operation
Weaknesses
- Physical size (4.1 m diameter) limits fit on smaller hulls or vessels with restricted bow space
- High power demand (≈4.5 MW) increases fuel consumption of the ship’s auxiliary system
- Requires substantial hull penetration and reinforcement, adding to installation cost
- May need dedicated hydraulic/electrical supply infrastructure not present on older ships
Typical Vessels:
Container ships (>150 m)Crude oil & product tankersLNG/LPG carriersCruise linersOffshore support vessels with DP requirements
Decision Guide: Choose if the vessel needs strong bow thrust for port entry/exit, dynamic positioning or emergency maneuvering and has sufficient bow volume to accommodate a 4.1 m duct. Avoid on smaller ships where space is limited, on vessels with low auxiliary power capacity, or when a lower‑cost, lower‑power thruster would meet the maneuverability requirements.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HRP-TT-4500 stern
unverified
· 4500.0 kW
· high‑power tunnel thruster
Power (kW)
4500
Thrust (kN)
540.0
Diameter (mm)
4100
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust output (≈540 kN) suitable for the largest merchant ships
- Large duct diameter (4.1 m) reduces cavitation and improves efficiency
- Robust steel housing designed for harsh marine environments
- Modular design allows integration with variable‑frequency drives for fine speed control
- Proven Holland Roer engineering reputation for reliability
Weaknesses
- Requires a substantial hull cut‑out; not suitable for vessels with limited stern space
- High electrical power demand (≈4.5 MW) may necessitate upgrades to ship’s power system
- Installation often needs reinforcement of the surrounding structure, increasing build cost
- Spare‑part inventory can be larger due to the size and custom nature of the unit
- Limited availability of detailed performance data pending verification
Typical Vessels:
VLCC (Very Large Crude Carrier)ULCV (Ultra Large Container Vessel)LNG carrierOffshore supply vesselDP‑class tanker or bulk carrier
Decision Guide: Choose if the vessel requires extreme lateral thrust for DP operations, tight port manoeuvring, or has sufficient stern space and power generation capacity. Avoid on smaller ships, vessels with restricted hull openings, or when a lower‑cost, lower‑power thruster meets the maneuverability requirements.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HRP-TT-5000 bow
unverified
· 5000.0 kW
· tunnel thruster
Power (kW)
5000
Thrust (kN)
600.0
Diameter (mm)
4500
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust‑to‑power ratio (600 kN at 5 MW) suitable for mega‑vessels
- Robust duct design minimizes cavitation and extends service life
- Integrated control system compatible with most DP packages
- Proven reliability on LNG carriers, cruise ships and offshore platforms
- Modular installation allows relatively straightforward retrofits
Weaknesses
- Large hull penetration (4.5 m diameter) requires significant structural reinforcement
- High electrical power demand increases onboard generation load
- Fixed thrust direction limits maneuverability compared with azimuth units
- Installation and commissioning costs are substantial
- Weight and size may restrict use on smaller or weight‑sensitive vessels
Typical Vessels:
LNG CarrierCruise ShipVery Large Container VesselBulk Carrier (>200 kt)FPSO / Offshore Supply Vessel
Decision Guide: Choose if you need maximum bow thrust for a vessel >150 m with limited space for azimuth thrusters and require proven, low‑cavitation performance for DP or tight port maneuvers. Avoid on smaller ships where the duct size, power consumption and cost outweigh the benefit, or when 360° thrust vectoring is essential.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HRP-TT-5000 stern
unverified
· 5000.0 kW
· tunnel thruster
Power (kW)
5000
Thrust (kN)
600.0
Diameter (mm)
4500
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (≈600 kN) suitable for mega‑size ships
- Robust tunnel design with cavitation‑reduction features
- Integrated control electronics compatible with most DP systems
- Proven reliability in long‑term offshore and tanker service
- Modular installation allowing retrofits on existing hulls
Weaknesses
- High power demand (≈5 MW) requiring substantial electrical/hydraulic supply
- Large tunnel diameter (4.5 m) limits placement to vessels with ample stern space
- Heavy and bulky, increasing overall ship weight and affecting stability calculations
- Higher acquisition and installation cost compared with lower‑rated thrusters
- Maintenance access can be challenging due to size
Typical Vessels:
VLCC (Very Large Crude Carrier)ULCV (Ultra‑Large Container Vessel)LNG carrierOffshore supply vessel (OSV) with DP3 capabilityLarge cruise ship
Decision Guide: Choose if the vessel requires extreme low‑speed thrust for safe berthing, unberthing or dynamic positioning on ships >200 000 gt where standard thrusters are insufficient. Avoid on smaller vessels, in power‑limited installations, or when hull space cannot accommodate a 4.5 m tunnel.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Hydromaster
44
HM-TT-50 bow
unverified
· 50.0 kW
· tunnel thruster
Power (kW)
50
Thrust (kN)
6.0
Diameter (mm)
540
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (6 kN at only 50 kW) improves maneuverability without excessive engine load.
- Relatively small tunnel diameter (540 mm) fits in limited hull space, allowing retrofits on existing ships.
- Standard bow mounting and control interface simplify integration with ship’s navigation console.
- Robust duct construction reduces vibration and prolongs service life under typical port‑maneuvering cycles.
Weaknesses
- Maximum thrust of 6 kN may be insufficient for large vessels or high‑speed dynamic positioning requirements.
- Tunnel geometry can promote cavitation at higher RPMs, increasing noise and wear if operated near design limits.
- Installation requires hull penetration and precise duct sealing, adding dry‑dock time and cost.
- Limited thrust range compared with azimuth thrusters reduces flexibility for tight berth handling.
Typical Vessels:
Offshore supply vesselCoastal container shipSmall tanker (up to ~5,000 GT)FerryCruise‑ship tender
Decision Guide: Choose if: you need a compact, cost‑effective bow thruster delivering moderate thrust for vessels up to roughly 5,000 GT and have limited hull space. Avoid if: the vessel requires high thrust (>10 kN), dynamic positioning capability, or you prefer an azimuth unit for greater maneuvering freedom.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
HM-TT-50 stern
unverified
· 50.0 kW
· tunnel thruster
Power (kW)
50
Thrust (kN)
6.0
Diameter (mm)
540
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Compact 540 mm tunnel diameter fits into medium‑size hull sections
- Adequate 6 kN thrust for vessels up to ~5 000 dwt, improving docking control
- Stern placement enhances aft maneuverability and reduces propeller wash interference
- Relatively low power consumption compared with larger thrusters of similar thrust
- Simple installation – integrates into existing hull structure without external pods
Weaknesses
- Thrust may be insufficient for large tankers, cruise ships or high‑wind port conditions
- Tunnel size limits retrofit options on vessels with narrow aft sections
- Typical tunnel thrusters generate cavitation noise and vibration that may require mitigation
- Maintenance of bearing and seal assemblies can be frequent in harsh marine environments
- Fixed thrust direction; no azimuth capability for 360° vectoring
Typical Vessels:
Handymax bulk carrierSmall container ship (up to ~5 000 dwt)Coastal tankerOffshore supply vesselFerry or passenger craft operating in confined ports
Decision Guide: Choose the HM‑TT‑50 when a medium‑size vessel needs reliable, moderate thrust for port entry/exit and has limited aft space. Avoid it on very large ships, vessels requiring high DP performance, or where noise/cavitation must be minimized.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
HM-TT-75 bow
unverified
· 75.0 kW
· tunnel thruster
Power (kW)
75
Thrust (kN)
9.0
Diameter (mm)
560
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (9 kN from 75 kW) for its size class
- Compact 560 mm duct fits well on vessels with limited bow space
- Tunnel design provides good protection of the propeller and reduced risk of fouling
- Relatively low acoustic signature compared with open‑propeller thrusters
- Standard 400 V electrical interface simplifies integration on many ship power systems
Weaknesses
- Maximum thrust (9 kN) may be insufficient for large vessels or high‑wind/strong‑current conditions
- Tunnel geometry can promote cavitation at high RPM, requiring careful blade selection
- Maintenance access to bearings and seals is more involved than on external azimuth units
- Limited thrust vectoring – only straight‑ahead lateral force
- Performance drops noticeably in very shallow water due to reduced inflow
Typical Vessels:
Offshore supply vesselCoastal ferrySmall container feeder (up to ~3,000 gt)Cruise ship tenderPatrol or research vessel
Decision Guide: Choose if the vessel requires a moderate‑power bow thruster for improved docking and low‑speed maneuvering, has limited bow space, and operates primarily in coastal or port environments. Avoid if the ship needs high thrust (>12 kN), operates in extreme weather/current conditions, or prefers an azimuthing unit with 360° thrust vectoring.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HM-TT-75 stern
unverified
· 75.0 kW
· tunnel thruster
Power (kW)
75
Thrust (kN)
9.0
Diameter (mm)
560
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (≈0.12 kN/kW) for its size
- Compact tunnel design fits tight hull spaces, especially at the stern
- Robust stainless‑steel duct and propeller with proven bearing life
- Low acoustic signature compared with azimuth units of similar power
- Straightforward integration with existing ship‑control systems
Weaknesses
- Fixed‑direction thrust limits maneuverability versus azimuth thrusters
- Maximum thrust (9 kN) may be insufficient for larger vessels or strong currents
- Cavitation can appear at high RPMs, requiring careful propeller selection
- Maintenance access is tighter in stern installations than bow locations
- No built‑in variable‑frequency drive; external controller required
Typical Vessels:
Offshore Supply VesselCoastal FerryWorkboat / Utility vesselSmall Bulk Carrier (≤2,000 GT)Patrol or Coast Guard craft
Decision Guide: Choose if: you need a cost‑effective, low‑noise maneuvering aid for vessels up to ~2,000 GT with limited hull space and can accept fixed‑direction thrust. Avoid if: the vessel requires high thrust levels, 360° vectoring, or operates in very strong currents where an azimuth thruster would be more efficient.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
HM-TT-100 bow
unverified
· 100.0 kW
· tunnel thruster
Power (kW)
100
Thrust (kN)
12.0
Diameter (mm)
580
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (12 kN at 100 kW) for its size
- Compact 580 mm tunnel fits most bow spaces on medium‑size vessels
- Proven Hydromaster design with low acoustic signature and easy routine maintenance
- Integrated control electronics compatible with common bridge automation systems
Weaknesses
- Maximum thrust of 12 kN may be insufficient for large tankers or high‑power DP requirements
- Hull penetration required; installation can be complex and costly compared with azimuth units
- Potential cavitation at full load in shallow water conditions
- Less maneuverability than a 360° azimuth thruster for vessels needing tight turning circles
Typical Vessels:
FerryOffshore supply vesselCruise ship (mid‑size)Container feederCoastal bulk carrier
Decision Guide: Choose if you need a reliable, space‑efficient bow thruster for vessels up to ~150 m with moderate thrust requirements and prefer a proven tunnel design at lower cost. Avoid if the vessel demands higher thrust (>15 kN), full 360° thrust vectoring, or minimal hull modifications.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HM-TT-100 stern
unverified
· 100.0 kW
· electric tunnel thruster
Power (kW)
100
Thrust (kN)
12.0
Diameter (mm)
580
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (12 kN at only 100 kW).
- Compact 580 mm tunnel diameter fits a wide range of hull forms.
- Designed for stern installation, allowing better flow and reduced interference with bow thrusters.
- Standardised mounting hardware simplifies retrofit on existing vessels.
Weaknesses
- Maximum thrust may be insufficient for large tankers or high‑speed DP vessels.
- Tunnel geometry can be prone to cavitation in very shallow water or at high RPMs.
- Stern placement can limit access for routine inspection and maintenance.
- No publicly documented certifications; class approval must be verified with the manufacturer.
Typical Vessels:
Offshore supply vesselCoastal tankerFerryContainer feederWorkboat
Decision Guide: Choose if you need a moderate‑power thruster for vessels up to about 30 kt service speed, where space is limited and a stern installation offers better flow. Avoid on very large ships requiring >15 kN thrust or when class societies demand specific type approvals that are not yet confirmed for this model.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HM-TT-150 bow
unverified
· 150.0 kW
· electric tunnel thruster
Power (kW)
150
Thrust (kN)
18.0
Diameter (mm)
620
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (≈0.12 kN/kW) for its size class
- Compact 620 mm duct fits in vessels with limited bow space
- Direct‑drive electric motor reduces mechanical complexity and maintenance
- Integrated cooling system suitable for continuous low‑speed operation
- Standardized mounting simplifies installation on new builds or retrofits
Weaknesses
- Maximum thrust of 18 kN may be insufficient for very large tankers or high‑draft vessels
- Tunnel geometry can generate higher hull resistance when the thruster is not in use
- Requires dedicated power supply and cooling capacity on board
- Noise and vibration levels are higher than some azimuth pod solutions
Typical Vessels:
Offshore Supply VesselFerryCoastal Container Ship (up to ~5 000 gt)Cruise‑ship tenderWorkboat / Utility vessel
Decision Guide: Choose if you need a reliable, medium‑size bow thruster for vessels up to about 10 000 gt where space is limited and a proven electric drive is preferred. Avoid if the ship requires thrust above 20 kN, ultra‑low vibration/noise solutions, or if hull form constraints prevent tunnel installation.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HM-TT-150 stern
unverified
· 150.0 kW
· Tunnel thruster
Power (kW)
150
Thrust (kN)
18.0
Diameter (mm)
620
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust-to-power ratio (18 kN from 150 kW) for its compact size
- Relatively small duct diameter (620 mm) eases integration in vessels with limited stern space
- Hydromaster reputation for robust construction and long service life
- Optional variable‑frequency drive allows fine thrust control and fuel savings
Weaknesses
- Maximum thrust may be insufficient for very large tankers or high‑speed DP operations
- Wear rings in the tunnel require regular inspection and replacement, increasing maintenance effort
- Performance can degrade noticeably in heavy sea states due to limited propeller wash
- Installation demands a dedicated stern tunnel, involving structural modifications
Typical Vessels:
ContainerGeneral CargoRo‑RoOffshore Support VesselCruise Ship (mid‑size)
Decision Guide: Choose if: you need a compact, high‑thrust stern thruster for vessels up to medium displacement where space is limited and precise low‑speed control is required (e.g., DP1 offshore supply or mid‑size container ships). Avoid if: the vessel requires higher thrust levels, operates in extreme sea conditions regularly, or you prefer azimuthing units for greater maneuverability.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HM-TT-200 bow
unverified
· 200.0 kW
· electric tunnel thruster
Power (kW)
200
Thrust (kN)
24.0
Diameter (mm)
660
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (24 kN from 200 kW) improves maneuverability
- Relatively compact 660 mm tunnel diameter fits into typical bow spaces on medium vessels
- Electric drive offers low emissions and easier integration with ship power systems
- Robust tunnel construction reduces wear in abrasive port environments
Weaknesses
- Tunnel geometry can be prone to cavitation when operating at high RPM or in shallow water
- Requires regular inspection and cleaning of the tunnel lining to prevent fouling
- Electric motor cooling and power supply must be accommodated in the vessel’s electrical layout
- Maximum thrust may be insufficient for very large vessels (>30 000 DWT) or heavy‑weather operations
Typical Vessels:
Container ship (up to ~30 000 DWT)Bulk carrier (up to ~25 000 DWT)General cargo vesselOffshore support vesselCruise ferry
Decision Guide: Choose if: you need a reliable 24 kN bow thrust on a medium‑size ship and have space for a 660 mm tunnel; you prefer an electric drive for lower emissions and easier integration. Avoid if: the vessel requires higher thrust levels, operates frequently in very shallow water where cavitation risk is high, or has severe weight/space constraints that preclude a tunnel thruster of this size.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HM-TT-200 stern
unverified
· 200.0 kW
· tunnel thruster
Power (kW)
200
Thrust (kN)
24.0
Diameter (mm)
660
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (24 kN from 200 kW) for effective low‑speed control
- Relatively compact tunnel diameter (660 mm) simplifies stern integration on medium‑size vessels
- Direct‑drive electric motor reduces mechanical complexity and improves reliability
- Low acoustic signature compared with larger azimuth thrusters, beneficial for passenger comfort
Weaknesses
- Tunnel geometry can limit efficiency at higher vessel speeds; thrust drops off quickly beyond ~5 kn lateral speed
- Potential for cavitation in shallow water or high‑load conditions, requiring careful hull reinforcement
- Maintenance access to the internal motor and bearings may be restricted by the confined tunnel space
- Limited azimuth capability – provides only transverse thrust, not full 360° vectoring
Typical Vessels:
Container ships (up to ~8 000 gt)General cargo vesselsOffshore supply & utility vesselsFerries and Ro‑Ro shipsMedium‑size cruise liners
Decision Guide: Choose if: you need a cost‑effective, high‑thrust transverse thruster for vessels up to medium size where space at the stern is limited and precise low‑speed manoeuvring is required. Avoid if: you require full azimuth thrust, operate frequently in deep‑water high‑speed transits, or have strict cavitation constraints that demand a larger tunnel or alternative propulsion.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HM-TT-250 bow
unverified
· 250.0 kW
· tunnel thruster
Power (kW)
250
Thrust (kN)
30.0
Diameter (mm)
700
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (30 kN at 250 kW)
- Compact 700 mm diameter fits in vessels with limited hull space
- Proven Hydromaster design with low vibration and noise levels
- Straightforward installation in bow tunnels
- Standardized control interface compatible with most ship automation systems
Weaknesses
- Maximum thrust may be insufficient for very large or high‑draft vessels
- Single‑unit configuration offers limited redundancy
- Requires regular bearing and seal maintenance typical of tunnel thrusters
- Noise and cavitation can increase at full power in shallow water
Typical Vessels:
Offshore supply vesselFerryContainer ship (up to ~150 m LOA)Small to medium tankerCruise‑ship tender
Decision Guide: Choose if you need a reliable 30 kN bow thruster for vessels up to about 20,000 DWT where hull space is limited and a compact tunnel solution is preferred. Avoid if the vessel requires higher thrust levels, dual‑unit redundancy, or operates primarily in very shallow water where cavitation risk is high.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HM-TT-250 stern
unverified
· 250.0 kW
· tunnel thruster
Power (kW)
250
Thrust (kN)
30.0
Diameter (mm)
700
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (30 kN at 250 kW) for compact installations
- Relatively small hull penetration (700 mm diameter) fits medium‑size vessels
- Hydromaster’s proven mechanical design with low maintenance requirements
- Optional variable frequency drive enables fine thrust control and energy savings
- Integrated cooling system reduces risk of overheating in continuous port operations
Weaknesses
- Performance drops sharply at higher vessel speeds; not suited for high‑speed maneuvering
- Potential cavitation and noise at full power, which may be a concern for passenger vessels
- Hull penetration required; installation can be complex on existing ships
- Less effective than azimuth thrusters for rapid directional changes in heavy seas
- Limited thrust vectoring – only straight‑line lateral force
Typical Vessels:
Container shipCruise linerFerryOffshore supply vesselSmall tanker
Decision Guide: Choose if you need a compact, high‑thrust stern thruster for port docking, station‑keeping or low‑speed maneuvering on vessels where hull space is limited and budget constraints favour proven tunnel technology. Avoid if the vessel operates frequently in heavy seas, requires rapid multi‑directional thrust, or has strict noise‑abatement requirements that favor azimuth or podded thrusters.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HM-TT-300 bow
unverified
· 300.0 kW
· tunnel thruster
Power (kW)
300
Thrust (kN)
36.0
Diameter (mm)
740
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (36 kN) relative to power rating (300 kW)
- Large 740 mm duct improves hydraulic efficiency and reduces cavitation risk
- Compact bow installation compatible with typical ship hull forms
Weaknesses
- Relatively large duct diameter may limit placement on vessels with narrow bow sections
- High electrical power demand (300 kW) requires adequate onboard supply capacity
- Brand visibility is limited, which can affect spare‑part availability and support
Typical Vessels:
Medium‑size tankers (up to ~30,000 dwt)Container ships (up to ~20,000 teu)Offshore supply vesselsBulk carriers (up to ~40,000 dwt)
Decision Guide: Choose if you need strong bow thrust for vessels up to medium size and have sufficient hull space for a 740 mm duct. Avoid if the vessel has tight bow geometry, limited power generation capacity, or if you prefer a brand with widely documented support networks.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HM-TT-300 stern
unverified
· 300.0 kW
· tunnel thruster
Power (kW)
300
Thrust (kN)
36.0
Diameter (mm)
740
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (36 kN from 300 kW) for its size
- Compact tunnel geometry fits within standard hull sections
- Robust, low‑maintenance brushless motor and sealed hydraulic system
- Integrated control unit compatible with most bridge consoles
- Proven performance in stern‑installation where space is limited
Weaknesses
- Provides only fixed‑direction thrust; no 360° vectoring like azimuth units
- Hull penetration required, increasing risk of water ingress if seals fail
- Access for routine inspection can be restricted by the tunnel housing
- Noise and vibration levels rise noticeably at full power
- Less effective for vessels requiring high‑precision DP compared with pod thrusters
Typical Vessels:
Product tankerChemical tankerOffshore supply vessel (OSV)Small container shipRo‑Ro ferry
Decision Guide: Choose if: you need a cost‑effective, high‑thrust solution for stern‑mounted lateral control on medium‑size vessels and DP requirements are modest. Avoid if: the vessel demands full azimuth thrust, ultra‑low vibration, or highest‑grade class approvals that are only granted to pod/azimuth systems.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HM-TT-400 bow
unverified
· 400.0 kW
· tunnel thruster
Power (kW)
400
Thrust (kN)
48.0
Diameter (mm)
820
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (48 kN at 400 kW) suitable for large vessels
- Large 820 mm tunnel diameter provides efficient water flow and reduced cavitation risk
- Robust, low‑maintenance design typical of Hydromaster’s tunnel units
- Compact hull penetration compared with azimuth thrusters, saving deck space
- Straightforward integration with existing ship control systems
Weaknesses
- Requires a relatively large hull opening (820 mm) which may affect structural integrity
- Fixed thrust direction; cannot rotate like an azimuth unit
- Higher power demand than smaller thrusters, impacting fuel consumption during DP operation
- Potential for increased noise and vibration at full load
- Limited suitability for vessels with very shallow draft or restricted hull space
Typical Vessels:
Container shipBulk carrierCruise linerOffshore supply vesselLNG/LPG carrier
Decision Guide: Choose if the vessel needs high bow thrust for tight berthing, dynamic positioning or maneuvering in confined ports and can accommodate a ~0.8 m hull opening. Avoid if space for hull penetration is limited, a rotating azimuth thruster is preferred, or power budget is constrained.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HM-TT-400 stern
unverified
· 400.0 kW
· tunnel thruster
Power (kW)
400
Thrust (kN)
48.0
Diameter (mm)
820
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (48 kN) relative to power rating, giving strong maneuverability at the stern
- Compact 820 mm duct diameter fits within typical hull sections without excessive structural modification
- Robust stainless‑steel construction common to Hydromaster units, offering good corrosion resistance and low maintenance
- Integrated control electronics compatible with most ship bridge systems for easy DP integration
Weaknesses
- 400 kW power demand can be significant for vessels with limited auxiliary generation capacity
- Tunnel geometry may generate higher acoustic noise and vibration compared with azimuth thrusters
- Installation requires a relatively large hull opening, potentially limiting use on smaller or heavily compartmentalised ships
- Limited thrust vectoring (fixed direction) – not suitable where 360° thrust is required
Typical Vessels:
Offshore Supply VesselCruise ShipContainer ShipProduct TankerRo‑Ro Ferry
Decision Guide: Choose if: you need strong, reliable stern thrust for DP or tight berthing on a vessel that can accommodate an 820 mm tunnel and has sufficient auxiliary power. Avoid if: space for the duct is constrained, acoustic noise is a critical issue, or a fully rotatable azimuth thruster would better meet maneuverability requirements.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HM-TT-500 bow
unverified
· 500.0 kW
· tunnel thruster
Power (kW)
500
Thrust (kN)
60.0
Diameter (mm)
900
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (60 kN) for its power rating, giving strong bow control in tight ports
- Large 900 mm tunnel diameter provides efficient water flow and lower cavitation risk
- Compact bow‑mounting arrangement fits vessels with limited hull space compared to larger azimuth units
- Integrated cooling system designed for continuous low‑speed operation
- Modular design simplifies installation and maintenance
Weaknesses
- 500 kW power demand can be a significant load on the ship's electrical plant
- Physical size of the tunnel may limit retrofit options on smaller hulls or vessels with shallow bow sections
- Limited to applications requiring ≥50 kN thrust; over‑spec for small ferries or tugs
- No publicly documented dual‑fuel or hybrid variant, restricting use on low‑emission projects
- Absence of widely advertised class certifications may require additional approval steps
Typical Vessels:
Container ships (5 000–10 000 TEU)Product tankers and chemical carriersBulk carriers (30 000–80 000 dwt)Offshore supply vesselsCruise liners (mid‑size)
Decision Guide: Choose if: you need strong bow thrust for precise docking or dynamic positioning on a vessel that can accommodate a 900 mm tunnel and has sufficient electrical generation capacity. Avoid if: hull space is constrained, the vessel’s power plant cannot support a 500 kW motor, or the required thrust is below 50 kN making the unit oversized.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HM-TT-500 stern
unverified
· 500.0 kW
· tunnel thruster
Power (kW)
500
Thrust (kN)
60.0
Diameter (mm)
900
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Provides high thrust (60 kN) relative to its power rating, improving docking control.
- Compact duct diameter (900 mm) fits in vessels with limited hull space.
- Stern mounting aids reverse‑heading maneuvers and dynamic positioning.
- 500 kW motor matches the power budgets of medium‑size commercial ships.
Weaknesses
- Relatively high electrical demand for a tunnel thruster of this size.
- Installation in the stern may require additional hull reinforcement.
- Typical tunnel‑thruster noise and vibration levels can affect crew comfort.
- Effectiveness decreases at higher vessel speeds where flow through the duct becomes turbulent.
Typical Vessels:
General cargoContainer ship (up to ~30,000 DWT)Medium tankerOffshore supply vessel
Decision Guide: Choose if you need a robust stern thruster delivering ≥60 kN thrust for vessels up to medium size and have sufficient power allocation. Avoid if the ship has strict noise limits, very limited hull space, or operates primarily at high speeds where tunnel‑thruster efficiency drops.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
HM-TT-600 bow
unverified
· 600.0 kW
· tunnel thruster
Power (kW)
600
Thrust (kN)
72.0
Diameter (mm)
980
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (72 kN @ 600 kW) for rapid lateral movement
- Compact 980 mm tunnel diameter fits into limited bow space on large vessels
- Robust, water‑cooled motor reduces overheating during prolonged use
- Low vibration and noise levels compared with external azimuth units
- Straightforward maintenance access through the hull opening
Weaknesses
- Significant power draw increases overall fuel consumption when used frequently
- Hull penetration required; installation is more invasive than retractable units
- Potential for cavitation at high thrust settings, especially in shallow water
- Limited effectiveness on very large vessels that require multiple thrusters for DP
- Weight and structural reinforcement requirements can add to construction cost
Typical Vessels:
Container ship (≥30 000 GT)Crude oil tankerLNG carrierCruise linerOffshore supply vessel
Decision Guide: Choose if: you need strong lateral thrust for berthing in confined ports, have sufficient bow space for a ~1 m tunnel, and require reliable, low‑maintenance maneuvering. Avoid if: the vessel is small (<30 000 GT), budget constraints limit power consumption, or hull modifications are undesirable.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
HM-TT-600 stern
unverified
· 600.0 kW
· tunnel thruster
Power (kW)
600
Thrust (kN)
72.0
Diameter (mm)
980
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (72 kN) suitable for large tankers and container ships
- Robust tunnel design with proven Hydromaster reliability and low maintenance
- Compact installation compared to external azimuth units, saving deck space
- Integrated cooling system typical of Hydromaster models reduces overheating risk
Weaknesses
- Large tunnel diameter (980 mm) may require significant hull modifications
- High power demand (600 kW) increases vessel electrical load and fuel consumption
- Fixed stern location limits flexibility; not usable for bow‑side maneuvering
- Potential cavitation at very high RPMs if not properly matched to hull form
Typical Vessels:
Crude Oil TankerProduct TankerContainer ShipBulk CarrierCruise Vessel
Decision Guide: Choose if you need >70 kN of stern thrust on a vessel that can accommodate a ~1‑m tunnel and you prefer a proven, low‑maintenance solution from an established supplier. Avoid if the ship has limited hull space, lower thrust requirements, or if you require bow‑side or 360° thrust capability offered by azimuth thrusters.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HM-TT-750 bow
unverified
· 750.0 kW
· electric tunnel thruster
Power (kW)
750
Thrust (kN)
90.0
Diameter (mm)
1100
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (≈90 kN) for its tunnel diameter, enabling strong lateral forces in tight berths
- Compact tunnel layout fits within standard bow sections of Panamax‑size ships
- Integrated cooling system reduces overheating during prolonged manoeuvres
- Robust stainless‑steel housing suited to harsh marine environments
Weaknesses
- 750 kW power demand requires substantial shipboard electrical capacity and cabling
- Large tunnel opening may reduce hull strength if not reinforced during installation
- Potential for cavitation at full‑load thrust, requiring careful propeller design
- Higher initial cost compared with lower‑power thrusters of similar size
Typical Vessels:
Container shipCrude oil tankerLNG carrierCruise linerLarge bulk carrier
Decision Guide: Choose if: you need a high‑thrust bow thruster for vessels >30 000 gt where precise low‑speed handling is critical and sufficient electrical power is available. Avoid if: the ship has limited shaft space, tight budget constraints, or the hull cannot accommodate a 1.1 m tunnel without major reinforcement.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HM-TT-750 stern
unverified
· 750.0 kW
· tunnel thruster
Power (kW)
750
Thrust (kN)
90.0
Diameter (mm)
1100
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (90 kN) provides strong low‑speed manoeuvring capability.
- Large 1.1 m tunnel diameter helps reduce cavitation and improves efficiency at high power levels.
- 750 kW motor size matches the requirements of vessels above 30,000 dwt for reliable stern assistance.
- Compact tunnel layout allows integration into existing hull structures without external protrusions.
Weaknesses
- High power rating leads to increased fuel consumption and electrical load.
- Diameter of 1100 mm requires significant hull penetration and internal space.
- Installation may be complex on vessels with limited stern volume or structural constraints.
- Spare‑part availability could be limited if Hydromaster has a smaller global service network.
Typical Vessels:
Crude oil tankerProduct tankerContainer shipBulk carrierOffshore supply vessel
Decision Guide: Choose if the vessel needs a powerful stern thruster for tight‑port docking, dynamic positioning support or emergency manoeuvring on ships >30,000 dwt. Avoid if hull space is constrained, power budget is limited, or a more widely supported brand is required for spare‑part logistics.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HM-TT-800 bow
unverified
· 800.0 kW
· tunnel thruster
Power (kW)
800
Thrust (kN)
96.0
Diameter (mm)
1140
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (96 kN) relative to power rating, suitable for large ships
- Large duct diameter (1140 mm) provides efficient water flow and reduced cavitation risk
- Compact bow installation frees deck space compared with external azimuth units
- Integrated motor cooling compatible with standard shipboard HVAC loops
Weaknesses
- High electrical demand (800 kW) may require dedicated generator capacity
- Significant hull penetration; installation must be carefully sealed to avoid leaks
- Noise and vibration can be noticeable in passenger‑focused vessels
- Limited thrust vectoring compared with azimuth or pod thrusters
Typical Vessels:
Container ship (≥8,000 TEU)Cruise linerLNG carrierLarge bulk carrierOffshore supply vessel
Decision Guide: Choose if: you need high bow thrust for precise docking of large vessels and have sufficient hull space for a 1.14 m duct; power plant can support an 800 kW dedicated thruster. Avoid if: vessel size is small, power budget limited, or you require full‑vectoring azimuth propulsion.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HM-TT-800 stern
unverified
· 800.0 kW
· tunnel thruster
Power (kW)
800
Thrust (kN)
96.0
Diameter (mm)
1140
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (96 kN) relative to power rating (800 kW), enabling rapid lateral movements.
- Large 1140 mm duct diameter reduces cavitation and improves efficiency at high thrust levels.
- Stern installation provides excellent control during reverse manoeuvres and tight berthing.
- Robust construction typical of Hydromaster units, suited for heavy‑duty marine environments.
Weaknesses
- 800 kW power demand can strain vessel electrical or hydraulic generation capacity.
- Physical size of the duct requires significant hull penetration and internal space.
- Higher installation cost compared with smaller thrusters or azimuth pods.
- Maintenance access may be limited on existing vessels without major retro‑fit.
Typical Vessels:
Large container shipsCrude oil tankersLNG carriersCruise linersOffshore supply vessels
Decision Guide: Choose if the vessel needs high‑power stern thrust for tight port manoeuvring, dynamic positioning assistance or rapid reverse response. Avoid if the ship has limited power generation capacity, space constraints in the hull, or if a lower‑cost azimuth pod can meet the manoeuvre requirements.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
HM-TT-1000 bow
unverified
· 1000.0 kW
· hydraulic tunnel thruster
Power (kW)
1000
Thrust (kN)
120.0
Diameter (mm)
1300
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (120 kN) suitable for large ships and tight port manoeuvring
- Large 1300 mm tunnel reduces cavitation and improves efficiency at high power
- Robust hydraulic drive offers reliable performance in harsh marine environments
- Integrated control interface compatible with most ship bridge systems
- Designed for easy retro‑fit into existing hull structures of appropriate size
Weaknesses
- Significant power demand (1 000 kW) increases vessel fuel consumption
- Large tunnel diameter requires substantial hull penetration and structural reinforcement
- Higher initial cost and installation time compared with smaller thrusters
- Hydraulic system adds complexity to maintenance programmes
- Spare‑part availability may be limited if Hydromaster has a small dealer network
Typical Vessels:
Container shipCrude oil tankerLiquefied gas carrierCruise linerOffshore supply vessel
Decision Guide: Choose if: you need >100 kN bow thrust for a vessel ≥150 m LOA, have sufficient hull space for a 1.3 m tunnel, and can accommodate the power and hydraulic infrastructure. Avoid if: the ship is small, power‑limited, or cannot allocate the required tunnel volume without major structural modifications.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HM-TT-1000 stern
unverified
· 1000.0 kW
· high‑power tunnel thruster
Power (kW)
1000
Thrust (kN)
120.0
Diameter (mm)
1300
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- 120 kN thrust at 1000 kW gives an excellent thrust‑to‑power ratio for a tunnel unit
- Large 1300 mm tunnel diameter provides high flow capacity and reduced cavitation risk
- Integrated monitoring and fault diagnostics simplify maintenance on board
- Compact stern placement frees deck space compared with external azimuth units
- Designed for continuous low‑speed operation, suitable for dynamic positioning support
Weaknesses
- 1300 mm tunnel requires significant hull cut‑out, limiting installation on smaller ships
- High electrical demand (1 MW) may exceed the power budget of vessels with limited generators
- Installation and alignment are complex and often require dry‑dock time
- Single‑unit design offers less redundancy than twin‑azimuth arrangements
- Potential for increased noise and vibration if not properly isolated
Typical Vessels:
Container ship (≥150 m LOA)Bulk carrierCruise linerLNG/LPG carrierOffshore supply vessel
Decision Guide: Choose if: you need high stern thrust for vessels >150 m, have sufficient hull space for a 1.3 m tunnel, and want integrated condition monitoring. Avoid if: the ship is small or power‑limited, you require redundant maneuvering systems, or you prefer azimuth thrusters for 360° thrust.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HM-TT-1200 bow
unverified
· 1200.0 kW
· tunnel thruster
Power (kW)
1200
Thrust (kN)
144.0
Diameter (mm)
1460
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (144 kN) relative to power consumption (1.2 MW)
- Compact ducted design fits within standard bow tunnel dimensions (≈1.46 m diameter)
- Integrated control electronics for precise vectoring and reduced pilot workload
- Robust steel housing suitable for harsh marine environments
- Low vibration and noise compared with external azimuth pods
Weaknesses
- Requires significant hull penetration and structural reinforcement
- Higher power demand can increase ship’s overall fuel consumption
- Maintenance of bearing and seal assemblies is more intensive than some pod‑type thrusters
- Potential for cavitation at very high thrust settings, especially in shallow water
- Limited to bow installations; not optimized for stern applications
Typical Vessels:
Container ships (>30 000 dwt)Crude oil and product tankersLNG carriersCruise linersOffshore supply vessels
Decision Guide: Choose if the vessel needs high bow thrust for port entry/exit, dynamic positioning or emergency maneuvering on ships >30 000 dwt and has sufficient power margin. Avoid if the ship is small, power‑limited, or if a simpler, lower‑cost stern thruster would meet the maneuverability requirements.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HM-TT-1200 stern
unverified
· 1200.0 kW
· high‑power tunnel thruster
Power (kW)
1200
Thrust (kN)
144.0
Diameter (mm)
1460
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (144 kN) relative to power rating, giving excellent low‑speed manoeuvring
- Large 1460 mm duct diameter reduces cavitation and improves efficiency at high thrust levels
- Robust construction typical of Hydromaster units, suited for continuous DP operation
- Integrated control electronics compatible with most bridge automation systems
- Proven design for stern installation where space is often more generous
Weaknesses
- High power demand (1200 kW) leads to significant fuel consumption when used frequently
- Large duct size requires substantial hull penetration and may limit applicability on smaller ships
- Installation and maintenance access can be challenging due to the size of the tunnel
- Weight and structural reinforcement requirements are higher than for smaller thrusters
- Limited to stern mounting; not suitable where a bow thruster is required
Typical Vessels:
Container ships (>8,000 TEU)Cruise linersLNG carriersOffshore supply vessels (OSV)FPSOs and large tankers
Decision Guide: Choose if: you need very high thrust for a large vessel with ample stern space, operate in confined ports or require DP support. Avoid if: the ship is smaller, has limited hull volume for a 1.46 m tunnel, or you prefer more compact azimuth thrusters for bow applications.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HM-TT-1500 bow
unverified
· 1500.0 kW
· electric tunnel thruster
Power (kW)
1500
Thrust (kN)
180.0
Diameter (mm)
1700
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (180 kN) provides excellent low‑speed maneuvering power.
- Large 1.7 m duct diameter reduces cavitation and improves efficiency.
- Modular, stainless‑steel construction simplifies installation and maintenance.
- Integrated variable‑frequency drive allows precise thrust control and energy savings.
- Robust design suited for continuous operation in demanding port environments.
Weaknesses
- High power rating leads to significant electrical load and operating cost.
- Requires substantial hull penetration and structural reinforcement at the bow.
- Size may limit installation on vessels with restricted bow space.
- Initial capital expense is higher than lower‑power thruster alternatives.
- Needs dedicated cooling water system and regular alignment checks to avoid vibration.
Typical Vessels:
Container shipBulk carrierCrude oil tankerLNG/LPG carrierCruise linerOffshore supply vessel
Decision Guide: Choose if the vessel exceeds ~100 000 dwt and requires strong bow thrust for tight port turns, dynamic positioning support, or emergency maneuverability. Avoid if hull space is limited, vessel size is small to medium (where a lower‑power thruster suffices), or electrical generation capacity cannot accommodate 1500 kW.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
HM-TT-1500 stern
unverified
· 1500.0 kW
· tunnel thruster
Power (kW)
1500
Thrust (kN)
180.0
Diameter (mm)
1700
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (180 kN) suitable for precise low‑speed manoeuvring of large ships
- Large 1700 mm tunnel diameter gives good hydraulic efficiency and lower cavitation risk
- Integrated cooling system designed for continuous high‑power operation
- Compact stern installation frees deck space compared to external azimuth units
Weaknesses
- High power rating (1 500 kW) leads to significant electrical demand and may require dedicated generators
- Physical size of the tunnel requires substantial hull penetration and structural reinforcement
- Installation and maintenance access can be limited in tight stern spaces
- Noise and vibration levels are higher than low‑power thrusters, requiring mitigation measures
Typical Vessels:
Cruise shipsLNG carriersOffshore supply vesselsLarge container vesselsRo‑Ro ferries
Decision Guide: Choose if the vessel needs high thrust for tight port manoeuvring, dynamic positioning or emergency backing and has sufficient electrical capacity. Avoid if the ship’s power plant cannot support a 1 500 kW load, space for a large tunnel is limited, or low‑noise operation is a primary requirement.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HM-TT-2000 bow
unverified
· 2000.0 kW
· hydraulic tunnel thruster
Power (kW)
2000
Thrust (kN)
240.0
Diameter (mm)
2100
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (240 kN) suitable for vessels >150 m LOA
- Large duct diameter reduces cavitation and improves efficiency at high power levels
- Integrated control electronics compatible with most DP‑1/DP‑2 systems
- Robust stainless‑steel housing designed for harsh marine environments
Weaknesses
- Very high power demand (≈2000 kW) increases fuel consumption when used frequently
- Large hull penetration required, limiting applicability on smaller ships or retrofits
- Maintenance access can be restricted due to the size of the duct and internal components
- Weight and centre‑of‑gravity impact not published, requiring detailed stability analysis
Typical Vessels:
Container shipCrude oil tankerLNG carrierCruise linerOffshore supply vessel
Decision Guide: Choose if the vessel requires high bow thrust for confined‑port operations, dynamic positioning support, or emergency maneuvering and can accommodate the power and hull‑penetration requirements. Avoid if the ship has limited power generation capacity, a narrow hull that cannot accept a 2.1 m duct, or if lower‑cost, lower‑power thrusters meet the manoeuvring needs.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HM-TT-2000 stern
unverified
· 2000.0 kW
· Stern tunnel thruster
Power (kW)
2000
Thrust (kN)
240.0
Diameter (mm)
2100
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (240 kN) suitable for large ships and tight port operations
- Large 2100 mm tunnel diameter provides efficient water flow and good thrust‑to‑power ratio
- Integrated into the stern, improving handling during reverse thrust and dynamic positioning
Weaknesses
- Requires a sizable hull opening (≈2.1 m) which may limit installation on smaller vessels
- Higher power demand (2000 kW) increases fuel consumption compared with lower‑rated units
- Potential for cavitation at maximum thrust if not matched with proper propeller design
Typical Vessels:
Crude oil tankerContainer shipBulk carrierCruise linerOffshore supply vessel
Decision Guide: Choose if the vessel needs strong stern thrust for berthing, un‑berthing or dynamic positioning and has sufficient hull space for a 2.1 m tunnel. Avoid if hull geometry is constrained, power budget is limited, or the ship’s maneuverability requirements are modest.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
HM-TT-2500 bow
unverified
· 2500.0 kW
· high‑power tunnel thruster
Power (kW)
2500
Thrust (kN)
300.0
Diameter (mm)
2500
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (300 kN) suitable for large ships and DP operations
- Large 2.5 m duct diameter provides efficient water flow and reduced cavitation risk at design speed
- Robust hydraulic drive rated for continuous 2500 kW operation
- Standard bow‑mounting simplifies integration on new builds and retrofits
- Compatible with typical ship power systems (400 V AC) without special voltage requirements
Weaknesses
- Large physical size limits installation to vessels with sufficient bow space
- High power consumption increases fuel usage when operated frequently
- Hydraulic system complexity can raise maintenance costs and require specialized spares
- Potential for increased noise and vibration compared with smaller thrusters
- Limited market presence of Hydromaster may affect spare‑part lead times
Typical Vessels:
TankerContainer ShipBulk CarrierLNG CarrierOffshore Support Vessel
Decision Guide: Choose if: you need >250 kN bow thrust for vessels over ~150 m LOA, require reliable DP or tight‑berth maneuvering, and have sufficient bow volume for a 2.5 m duct. Avoid if: vessel size is small, space constraints exist, or operating budgets cannot accommodate higher power and maintenance demands.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
HM-TT-2500 stern
unverified
· 2500.0 kW
· tunnel thruster
Power (kW)
2500
Thrust (kN)
300.0
Diameter (mm)
2500
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High power (2 500 kW) provides strong thrust (300 kN) for large vessels
- Large 2.5 m tunnel diameter gives efficient water flow and reduced slip loss
- Stern location improves astern maneuverability and aids DP operations
- Direct‑drive electric motor reduces mechanical complexity compared with hydraulic units
Weaknesses
- Physical size of the 2.5 m tunnel requires substantial hull penetration and internal space
- High electrical power demand may exceed the capacity of older shipboard generators
- Installation and alignment are critical; misalignment can cause vibration and cavitation
- Maintenance access is more difficult on stern installations compared with bow units
Typical Vessels:
Large Crude Oil TankerContainer Ship (>10,000 TEU)Bulk Carrier (≥30,000 dwt)Cruise ShipOffshore Supply Vessel with DP requirements
Decision Guide: Choose if the vessel requires a high‑thrust stern thruster for precise astern handling or dynamic positioning on ships >30 000 dwt and has sufficient electrical generation capacity. Avoid if hull space is limited, power supply is constrained, or a smaller, lower‑cost bow thruster would meet maneuvering needs.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HM-TT-3000 bow
unverified
· 3000.0 kW
· tunnel thruster
Power (kW)
3000
Thrust (kN)
360.0
Diameter (mm)
2900
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (360 kN) suitable for mega‑vessels and DP operations
- Large 2900 mm diameter reduces cavitation and improves efficiency
- Integrated control electronics compatible with most bridge systems
- Modular construction eases installation and maintenance
- Proven reliability in long‑haul container and cruise ship applications
Weaknesses
- High power demand (3 MW) increases fuel consumption and electrical load
- Large physical footprint requires substantial hull penetration space
- Heavy overall weight may affect vessel stability calculations
- Higher upfront cost compared with smaller thrusters
- Requires extensive ducting and sealing work during installation
Typical Vessels:
Container shipCruise linerBulk carrierLNG carrierOffshore supply vessel
Decision Guide: Choose if: you need maximum bow thrust for a vessel >150 m LOA, operate in tight ports or require DP support, and have sufficient power generation capacity. Avoid if: hull space is limited, the vessel’s power plant cannot accommodate an additional 3 MW load, or budget constraints preclude high‑cost thrusters.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
HM-TT-3000 stern
unverified
· 3000.0 kW
· high‑power tunnel thruster
Power (kW)
3000
Thrust (kN)
360.0
Diameter (mm)
2900
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (360 kN) for a single unit, enabling rapid stern‑side manoeuvring of large vessels
- Compact tunnel layout fits within standard hull openings without excessive external protrusion
- Integrated water‑cooling system designed for continuous DP operation
- Robust hydraulic drive rated for 3000 kW, offering reliable performance in harsh marine environments
Weaknesses
- High electrical power demand (3 MW) requires substantial onboard generation capacity
- Large tunnel diameter (2.9 m) may limit installation on vessels with restricted hull space
- Potential for cavitation at high thrust settings, requiring careful propeller design and monitoring
- Maintenance access to the internal impeller can be more involved than for azimuth thrusters
Typical Vessels:
Ultra‑large container shipsCruise linersLNG carriersOffshore supply vesselsDP‑class tankers
Decision Guide: Choose if: you need a single stern thruster capable of delivering >350 kN thrust for fast berthing, un‑berthing or DP assistance on large vessels and have sufficient generator capacity. Avoid if: hull space is limited, power plant cannot accommodate an extra 3 MW load, or you prefer azimuth units with 360° thrust vectoring.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HM-TT-3500 bow
unverified
· 3500.0 kW
· high-power tunnel thruster
Power (kW)
3500
Thrust (kN)
420.0
Diameter (mm)
3300
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (420 kN) suitable for large ships and DP support
- Large tunnel diameter (3300 mm) provides efficient water flow and lower cavitation risk
- Integrated variable‑frequency drive enables precise thrust control and energy savings
- Robust stainless‑steel housing and sealed motor for low maintenance in harsh marine environments
- Modular design allows relatively quick installation and replacement
Weaknesses
- Large physical size limits fitment on vessels with restricted bow space or narrow hull forms
- High power rating (3.5 MW) results in significant electrical demand and cooling water requirements
- Higher upfront cost compared with lower‑power thruster options
- Spare parts and service expertise may be less widely available than for more common brands
- Installation may require structural reinforcement of the hull due to high thrust loads
Typical Vessels:
Container ship (≥ 10,000 TEU)Crude oil or product tanker (≥ 150 kDWT)LNG carrierCruise linerOffshore supply vessel with DP capability
Decision Guide: Choose if the vessel requires very high bow thrust for safe maneuvering in confined ports, operates under dynamic positioning, or exceeds 150 kDWT where standard thrusters lack sufficient power. Avoid if hull geometry cannot accommodate a 3.3 m tunnel, electrical supply is limited, or the required thrust is well below 300 kN.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
HM-TT-3500 stern
unverified
· 3500.0 kW
· tunnel thruster
Power (kW)
3500
Thrust (kN)
420.0
Diameter (mm)
3300
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (420 kN) suitable for large tankers and container ships
- High power rating (3500 kW) enables rapid response for dynamic positioning
- Large duct diameter (3.3 m) provides efficient water flow and reduced cavitation
- Stern installation improves reverse‑maneuvering control in confined ports
Weaknesses
- Large hull penetration required, increasing installation complexity
- High electrical power demand may limit use on vessels with restricted generator capacity
- Physical size (3.3 m diameter) restricts fit to ships with ample stern space
- Potential for increased noise and vibration compared with smaller thrusters
Typical Vessels:
Crude oil tankerProduct tankerContainer ship (>10,000 TEU)Bulk carrier (≥150 kt)Cruise liner
Decision Guide: Choose if the vessel requires strong stern thrust for DP or tight‑port maneuvering and has sufficient electrical power and hull space. Avoid if the ship’s power plant is limited, space at the stern is constrained, or a lower‑cost, lower‑power thruster meets the operational needs.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
HM-TT-4000 bow
unverified
· 4000.0 kW
· tunnel bow thruster
Power (kW)
4000
Thrust (kN)
480.0
Diameter (mm)
3700
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (480 kN) suitable for mega‑size tankers and container ships
- Large 3.7 m duct diameter reduces cavitation and improves hydraulic efficiency
- Robust tunnel construction offers low maintenance and good resistance to fouling
- Integrated variable‑frequency drive enables precise thrust control for DP operations
- Proven design widely used in commercial shipyards for new builds
Weaknesses
- Requires substantial electrical supply (≈4 MW) and dedicated cooling infrastructure
- Physical size demands significant hull penetration space, limiting retrofit options on smaller ships
- Higher capital cost compared with lower‑power thrusters or azimuth pods for the same vessel class
- Noise and vibration levels rise sharply at maximum thrust, requiring additional acoustic mitigation
- Installation complexity can extend shipyard schedule
Typical Vessels:
Very Large Crude Carrier (VLCC)Ultra‑Large Container Ship (ULCS)LNG carrierOffshore supply vessel (large DP class)Cruise liner (≥150 m)
Decision Guide: Choose the HM‑TT‑4000 when a vessel has ample electrical generation capacity, needs maximum low‑speed thrust for port entry/exit or dynamic positioning, and can accommodate the large tunnel aperture. Avoid it on ships with limited hull space, lower power budgets, or where a smaller thruster or azimuth pod would meet maneuverability requirements more cost‑effectively.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HM-TT-4000 stern
unverified
· 4000.0 kW
· tunnel thruster
Power (kW)
4000
Thrust (kN)
480.0
Diameter (mm)
3700
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (480 kN) suitable for the largest tankers, cruise ships and offshore vessels
- Compact tunnel installation saves deck space compared with external azimuth units
- Robust sealed housing reduces corrosion risk in harsh seawater environments
- Integrated cooling system handles 4 MW of motor power reliably
- Proven design for high‑power applications with low maintenance intervals
Weaknesses
- Large hull penetration required; installation is complex and costly
- High electrical demand (≈4 MW) may exceed the power budget on smaller ships
- Noise and vibration levels can be significant at full power, requiring mitigation measures
- Limited effectiveness for low‑speed or low‑thrust maneuvers compared with smaller thrusters
- Initial capital cost is high relative to lower‑power tunnel units
Typical Vessels:
Very Large Crude Carrier (VLCC)Ultra‑Large Container Vessel (ULCV)Cruise ShipLNG CarrierOffshore Supply Vessel (OSV)
Decision Guide: Choose the HM‑TT‑4000 when a vessel requires extreme lateral thrust for safe docking, tight‑berth operations or dynamic positioning on ships above 150 000 gt. Avoid it on smaller vessels, where power availability, hull space and cost do not justify the high thrust capability.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
HM-TT-4500 bow
unverified
· 4500.0 kW
· tunnel thruster
Power (kW)
4500
Thrust (kN)
540.0
Diameter (mm)
4100
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (≈540 kN) suitable for mega‑vessels and offshore platforms
- Large 4.1 m duct provides efficient water flow and reduced cavitation risk at design load
- Robust steel housing with corrosion‑resistant lining for long service life in harsh marine environments
- Integrated cooling system allows continuous operation during extended manoeuvring periods
Weaknesses
- Large diameter requires substantial hull penetration space, limiting installation on smaller ships
- High power demand (≈4.5 MW) increases fuel consumption and electrical load
- Installation and alignment are complex and may require specialised dockyard facilities
- Initial procurement cost is higher than lower‑power alternatives
Typical Vessels:
Cruise shipsLNG carriersVery large crude carriers (VLCC)Offshore supply vesselsFloating production storage and offloading units (FPSO)
Decision Guide: Choose if: you need very high bow‑side thrust for a vessel >150 m LOA, operate in confined ports or require precise dynamic positioning. Avoid if: hull space is limited, the vessel’s power plant cannot support an additional ~4.5 MW load, or budget constraints favour smaller thrusters.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
HM-TT-4500 stern
unverified
· 4500.0 kW
· tunnel thruster
Power (kW)
4500
Thrust (kN)
540.0
Diameter (mm)
4100
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (540 kN) suitable for large ships
- Large duct diameter (4.1 m) reduces cavitation and improves efficiency
- Integrated steering control compatible with most bridge systems
- Robust, marine‑grade construction typical of Hydromaster products
- Proven design for stern installation on new‑build vessels
Weaknesses
- Very high power demand (4.5 MW) increases fuel consumption and electrical load
- Large hull penetration required, impacting structural design and corrosion protection
- Requires substantial cooling water flow; fouling can affect performance
- Maintenance of bearings and seals is intensive in harsh sea conditions
- Limited effectiveness at extremely low speeds due to tunnel blockage
Typical Vessels:
ContainerBulk CarrierTankerCruise ShipOffshore Support Vessel
Decision Guide: Choose if you need high thrust for a large vessel, have sufficient hull space for a 4.1 m duct, and require reliable stern‑side manoeuvring or DP support. Avoid if the ship has limited power generation capacity, tight hull constraints, or operates primarily at very low speeds where tunnel efficiency drops.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
HM-TT-5000 bow
unverified
· 5000.0 kW
· tunnel thruster
Power (kW)
5000
Thrust (kN)
600.0
Diameter (mm)
4500
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (≈600 kN) suitable for ultra‑large ships
- Large 4.5 m duct diameter reduces cavitation and improves efficiency
- Integrated cooling system allows continuous operation at full power
- Modular design simplifies installation in new builds
- Low‑noise blade geometry meets stringent acoustic standards
Weaknesses
- Enormous size limits retrofit options on smaller hulls
- High electrical demand (≈5 MW) requires robust shipboard power supply
- Significant hull penetration and structural reinforcement needed
- Maintenance access can be challenging due to duct dimensions
- Installation cost is higher than standard 2‑3 MW thrusters
Typical Vessels:
VLCCULCCLarge LNG carrierUltra‑large container ship (ULCV)Offshore supply vessel (OSV) – heavy lift variant
Decision Guide: Choose if: you need maximum bow thrust for a vessel >200 000 gt operating in confined ports or requiring dynamic positioning; you have sufficient onboard power and structural capacity. Avoid if: hull space is limited, power generation is constrained, or the vessel size does not justify the 600 kN thrust capability.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
HM-TT-5000 stern
unverified
· 5000.0 kW
· tunnel thruster
Power (kW)
5000
Thrust (kN)
600.0
Diameter (mm)
4500
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (≈600 kN) suitable for mega‑vessels
- Robust tunnel construction provides good protection against debris
- Stern location improves push‑pull control during docking and DP operations
- Modular design allows retrofit into existing hulls with a 4.5 m tunnel
Weaknesses
- Large tunnel diameter (≈4.5 m) consumes significant hull space
- High power rating (5 MW) leads to substantial electrical demand and operating cost
- Potential for cavitation at full‑load conditions if not properly sized for propeller speed
- Limited market presence of the Hydromaster brand may affect spare‑part availability
Typical Vessels:
Very Large Crude Carrier (VLCC)LNG carrierCruise shipOffshore supply vesselLarge container ship
Decision Guide: Choose if the vessel requires >500 kN of stern thrust for tight‑port maneuvering, DP or emergency stopping and has sufficient hull volume for a 4.5 m tunnel. Avoid if hull space is constrained, power supply is limited, or a more widely supported brand is preferred.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
Mitsubishi Thruster
44
MIT-TT-50 bow
unverified
· 50.0 kW
· tunnel thruster
Power (kW)
50
Thrust (kN)
6.0
Diameter (mm)
540
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (6 kN @ 50 kW) for its size
- Robust Mitsubishi build quality with proven service record
- Compact duct diameter (540 mm) fits into narrow hull sections
- Low maintenance tunnel design – no exposed propeller blades
- Integrated control interface compatible with most ship bridge systems
Weaknesses
- Maximum thrust of 6 kN limits use on larger vessels or high‑wind conditions
- Installation requires significant hull penetration and structural reinforcement
- Potential for cavitation at full power in shallow water
- Noise and vibration can be noticeable on small passenger vessels
- Limited availability of spare parts in remote ports compared with more common brands
Typical Vessels:
Coastal container ships (up to ~150 m LOA)General cargo & feeder vesselsOffshore support and supply vesselsFerries and Ro‑Ro craftSmall cruise liners and luxury yachts
Decision Guide: Choose if you need a reliable, space‑efficient bow thruster for vessels up to medium size where 6 kN thrust is sufficient for port entry and low‑speed maneuvering. Avoid on large tankers, ultra‑large container ships, or any vessel that requires higher thrust levels or DP‑class redundancy.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
MIT-TT-50 stern
unverified
· 50.0 kW
· Tunnel thruster
Power (kW)
50
Thrust (kN)
6.0
Diameter (mm)
540
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Compact duct size (540 mm) fits tight hull spaces while still providing useful thrust for maneuvering.
- High thrust‑to‑power ratio (6 kN @ 50 kW) gives good bollard pull for vessels up to ~5,000 GT.
- Mitsubishi’s proven bearing and seal design reduces maintenance intervals.
- Low acoustic signature compared with larger azimuth units, beneficial in noise‑sensitive ports.
Weaknesses
- Maximum thrust of 6 kN may be insufficient for large tankers or high‑wind offshore operations.
- Tunnel geometry can be prone to duct fouling; regular cleaning required to maintain performance.
- Limited azimuth capability – fixed‑direction only, so vessel must rely on rudders or additional thrusters for full vectoring.
Typical Vessels:
Offshore Supply VesselCoastal FerryWorkboat / Tug (small)Coastal Container ShipBulk carrier (up to ~5,000 GT)
Decision Guide: Choose if: you need a reliable, compact stern thruster for vessels under ~5,000 GT where space is limited and moderate thrust is sufficient. Avoid if: the vessel requires high bollard pull (>10 kN), full‑azimuth maneuverability, or operates in heavily fouled waters without regular cleaning capability.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
MIT-TT-75 bow
unverified
· 75.0 kW
· tunnel thruster
Power (kW)
75
Thrust (kN)
9.0
Diameter (mm)
560
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Compact 560 mm diameter fits in limited hull spaces
- 75 kW motor provides adequate thrust (9 kN) for vessels up to ~5,000 gt
- Integrated duct design improves thrust efficiency and reduces cavitation
- Mitsubishi’s proven reliability record and low maintenance requirements
Weaknesses
- Maximum thrust may be insufficient for large tankers or high‑speed DP operations
- Fixed tunnel geometry limits retrofit flexibility compared with azimuth thrusters
- Power rating (75 kW) restricts use on vessels requiring higher bollard pull
Typical Vessels:
Offshore supply vesselFerryCoastal cargo shipSmall container feederWorkboat / tug‑assist craft
Decision Guide: Choose if: you need a reliable, space‑efficient bow thruster for vessels up to ~5,000 gt with moderate thrust requirements and limited installation envelope. Avoid if: the vessel demands higher bollard pull (>12 kN), operates in extreme ice or high‑speed DP conditions, or requires azimuthing capability.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
MIT-TT-75 stern
unverified
· 75.0 kW
· tunnel thruster
Power (kW)
75
Thrust (kN)
9.0
Diameter (mm)
560
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (9 kN from 75 kW) for its size
- Compact 560 mm tunnel diameter fits into tight hull spaces
- Low acoustic signature compared with azimuth pods, beneficial in noise‑sensitive areas
- Simple installation and integration on existing stern structures
Weaknesses
- Limited thrust makes it unsuitable for very large vessels or high‑wind conditions
- Potential cavitation at maximum RPM, requiring careful propeller selection
- Maintenance of bearing housings can be labour‑intensive in harsh marine environments
- Fixed direction; cannot provide 360° thrust like a bow‑thruster/azimuth unit
Typical Vessels:
Offshore Supply Vessel (OSV)Coastal Container ShipFerrySmall Bulk CarrierWorkboat / Tug (up to ~2,000 GT)
Decision Guide: Choose if: you need a reliable, compact stern thruster for vessels up to about 2,000 GT where space is limited and noise control matters. Avoid if: the vessel requires higher thrust levels for extreme weather docking or prefers an azimuth‑type system with full 360° manoeuvrability.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
MIT-TT-100 bow
unverified
· 100.0 kW
· tunnel thruster
Power (kW)
100
Thrust (kN)
12.0
Diameter (mm)
580
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (12 kN @ 100 kW) for its size class
- Compact duct diameter (580 mm) eases installation in vessels with limited hull space
- Mitsubishi’s reputation for robust electric motor design and long service life
- Straight‑forward integration with standard bow thruster control consoles
Weaknesses
- Fixed‑direction thrust; cannot rotate like an azimuth pod
- Potential cavitation at high load if water flow is not optimised
- Maintenance of bearing and seal assemblies required in harsh sea water environments
- Limited maximum thrust compared with larger or multi‑unit thruster packages
Typical Vessels:
Container ships (up to ~8 000 TEU)Bulk carriers (handysize to panamax)General cargo vesselsOffshore supply & support vesselsCruise ships and ferries requiring bow assistance
Decision Guide: Choose if you need a reliable, space‑efficient bow thruster delivering ~12 kN thrust for medium‑size commercial vessels and you are satisfied with fixed transverse thrust. Avoid if the vessel requires higher thrust levels, azimuth steering capability, or ultra‑low noise performance typical of passenger‑comfort designs.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
MIT-TT-100 stern
unverified
· 100.0 kW
· tunnel thruster
Power (kW)
100
Thrust (kN)
12.0
Diameter (mm)
580
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (12 kN at 100 kW)
- Compact 580 mm tunnel diameter fits vessels with limited hull space
- Mitsubishi’s proven reliability and low maintenance intervals
- Integrated variable frequency drive provides fine speed control
- Stainless‑steel blade construction offers good corrosion resistance
Weaknesses
- Maximum thrust (12 kN) may be insufficient for larger vessels or high‑wind conditions
- Potential cavitation at full power in shallow water
- Installation requires significant hull penetration and structural reinforcement
- Higher acoustic noise compared with azimuth pod thrusters
- Not optimal for vessels exceeding roughly 10,000 DWT where higher thrust is required
Typical Vessels:
Offshore supply vesselCoastal container or general cargo ship (up to ~8,000 DWT)FerrySmall tankerWorkboat / tug‑assist craft
Decision Guide: Choose if you need a compact, high‑efficiency stern thruster delivering around 12 kN for vessels up to ~10,000 DWT where hull space is limited and precise low‑speed control is required. Avoid on large tankers, ultra‑large container ships or any vessel that demands thrust well above 15 kN, or when noise and cavitation are critical concerns.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
MIT-TT-150 bow
unverified
· 150.0 kW
· tunnel thruster
Power (kW)
150
Thrust (kN)
18.0
Diameter (mm)
620
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (18 kN from 150 kW)
- Compact 620 mm tunnel diameter fits medium‑size hulls
- Mitsubishi’s reputation for robust hydraulic drive systems
- Relatively low acoustic signature compared with azimuth units
Weaknesses
- Maximum thrust may be insufficient for very large vessels or high wind/current conditions
- Fixed‑direction thrust; no 360° vectoring capability
- Requires dedicated duct space within the hull, impacting structural layout
- Potential cavitation at high propeller speeds if not properly matched to hull form
Typical Vessels:
Container ship (up to ~150 m LOA)General cargo vesselOffshore supply vesselCoastal ferry / cruise ferrySmall to medium coastal tanker
Decision Guide: Choose if you need a reliable, compact bow thruster delivering moderate thrust for vessels up to ~150 m length where hull space is limited and a fixed‑direction system is acceptable. Avoid if the vessel requires higher thrust levels, full 360° thrust vectoring, or operates in extreme wind/current environments that exceed the 18 kN capability.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
MIT-TT-150 stern
unverified
· 150.0 kW
· tunnel thruster
Power (kW)
150
Thrust (kN)
18.0
Diameter (mm)
620
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (18 kN @ 150 kW) for its size
- Compact tunnel geometry fits into standard stern tunnels (≈620 mm diameter)
- Proven Mitsubishi reliability and low vibration levels
- Straightforward integration with existing ship electrical systems
- Relatively low initial cost compared with azimuth pods
Weaknesses
- Reduced efficiency in heavy seas or strong currents
- Potential hull stress at high thrust settings
- Cavitation risk if operated near maximum rating for prolonged periods
- Limited maneuverability compared with rotating (azimuth) thrusters
- Maintenance access can be constrained by tunnel location
Typical Vessels:
Container feederProduct tankerHandymax bulk carrierOffshore supply vesselCruise ship (mid‑size)
Decision Guide: Choose if: you need a reliable, cost‑effective stern thruster for vessels up to ~30 000 dwt with moderate docking requirements and have space for a 620 mm tunnel. Avoid if: the vessel requires very high thrust (>20 kN), operates in ice or extreme weather, or you prefer the greater maneuverability of azimuth or podded thrusters.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
MIT-TT-200 bow
unverified
· 200.0 kW
· tunnel thruster
Power (kW)
200
Thrust (kN)
24.0
Diameter (mm)
660
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (24 kN at only 200 kW)
- Compact 660 mm tunnel fits moderate‑size hulls without major structural changes
- Mitsubishi brand reputation for mechanical reliability and long service life
- Low acoustic and vibration signature, beneficial for passenger comfort
- Standard electrical interface compatible with most ship control systems
Weaknesses
- Maximum thrust may be insufficient for large vessels or high‑wind/sea‑state docking
- Tunnel geometry adds a small amount of hull resistance when the thruster is idle
- Access for internal maintenance can require dry‑docking or removal of interior panels
- Potential cavitation at full load in shallow water conditions
- No built‑in redundancy; a single unit must be complemented by other manoeuvring aids on critical vessels
Typical Vessels:
Offshore Supply Vessel (OSV)Ro‑Ro / Passenger FerryCruise ship tenderSmall container or feeder vessel (up to ~150 m LOA)Medium‑size bulk carrier or tanker (up to ~30 kt deadweight)
Decision Guide: Choose the MIT‑TT‑200 when a vessel needs reliable moderate bow thrust for docking and low‑speed manoeuvring, has limited hull space for a thruster tunnel, and values Mitsubishi’s proven service record. Avoid it on very large ships, DP‑critical platforms, or where thrust requirements exceed 25 kN or where additional redundancy is mandatory.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
MIT-TT-200 stern
unverified
· 200.0 kW
· tunnel thruster
Power (kW)
200
Thrust (kN)
24.0
Diameter (mm)
660
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (24 kN at 200 kW) for its size
- Compact 660 mm diameter fits medium‑size hull openings
- Mitsubishi’s reputation for reliability and low maintenance
- Relatively quiet operation compared with open‑propeller thrusters
- Straightforward retro‑fit into existing stern structures
Weaknesses
- Fixed thrust direction; requires helm control or separate steering gear
- Performance can degrade in very deep drafts or high sea states
- Hull penetration needed for installation, affecting structural integrity if not properly reinforced
- Less maneuvering flexibility than azimuth or pod‑type thrusters
- Power consumption higher than newer electric pod solutions for equivalent thrust
Typical Vessels:
Container ship (up to ~30,000 DWT)Bulk carrier (up to ~35,000 DWT)Product tankerOffshore supply vesselCruise ship (mid‑size)
Decision Guide: Choose if the vessel needs a proven, compact stern thruster for improved docking/undocking without requiring full 360° thrust capability and space is limited. Avoid if you require azimuth steering, operate in very deep water or high‑energy sea states, or are pursuing an all‑electric pod propulsion architecture.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
MIT-TT-250 bow
unverified
· 250.0 kW
· tunnel bow thruster
Power (kW)
250
Thrust (kN)
30.0
Diameter (mm)
700
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (30 kN from 250 kW) improves maneuvering efficiency
- Compact 700 mm tunnel fits within the hull of many mid‑size ships without excessive structural modification
- Mitsubishi’s reputation for robust, low‑maintenance marine propulsion components
- Modular design allows relatively quick installation and straightforward integration with common bridge control systems
- Proven performance in a variety of vessel classes, supporting reliable port entry/exit
Weaknesses
- Requires a dedicated 250 kW power supply, which may be limiting for vessels with constrained electrical generation capacity
- Installation demands sufficient hull space; retro‑fits on older ships can be costly and time‑consuming
- Noise and vibration levels are higher than some azimuth or pod thrusters, potentially affecting crew comfort in noise‑sensitive applications
- Maintenance of bearing and seal assemblies in the marine environment adds periodic downtime
- Fixed‑direction thrust limits flexibility compared with rotating (azimuth) thruster solutions
Typical Vessels:
Container ships (up to ~10,000 GT)Bulk carriers (mid‑size)Ro‑Ro ferries and short‑sea passenger vesselsOffshore supply vesselsCruise ships and large ferries
Decision Guide: Choose if the vessel needs strong low‑speed maneuverability in confined ports, has adequate hull space for a 700 mm tunnel, and can allocate a 250 kW power source. Avoid if the ship is small with limited power generation, requires omnidirectional thrust, or prioritises ultra‑low noise levels over raw thrust.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
MIT-TT-250 stern
unverified
· 250.0 kW
· tunnel thruster
Power (kW)
250
Thrust (kN)
30.0
Diameter (mm)
700
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Provides up to 30 kN of thrust for effective sideways maneuvering
- Compact 700 mm tunnel diameter fits medium‑size hull openings
Weaknesses
- Requires a hull opening of 700 mm, limiting installation on smaller vessels
- Maximum thrust of 30 kN may be insufficient for very large ships that need higher manoeuvring power
Decision Guide: Choose if you need a reliable mid‑size stern thruster with a good thrust‑to‑power ratio and can accommodate a 700 mm tunnel opening. Avoid if the vessel is too small to fit the tunnel or requires higher than 30 kN of thrust for safe maneuvering.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
MIT-TT-300 bow
unverified
· 300.0 kW
· electric tunnel thruster
Power (kW)
300
Thrust (kN)
36.0
Diameter (mm)
740
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (36 kN @ 300 kW) provides strong lateral force for docking and low‑speed maneuvering.
- Compact 740 mm tunnel diameter fits within the bow sections of many large vessels without excessive hull penetration.
- Direct‑drive electric motor reduces hydraulic fluid handling, maintenance intervals and vibration compared with hydraulic thrusters.
- Mitsubishi’s proven marine propulsion heritage offers reliable long‑term operation and global support network.
- Low acoustic and electromagnetic emissions are advantageous for port‑area operations and compliance with noise regulations.
Weaknesses
- 300 kW electrical demand requires a robust shipboard power supply and may impact overall energy budgeting.
- Fixed tunnel orientation limits thrust direction to port‑starboard or starboard only; no 360° azimuth capability.
- Installation involves hull penetration and structural reinforcement, increasing dockyard time and cost.
- Potential for cavitation at maximum thrust in shallow water conditions, which can reduce efficiency and increase wear.
- Large tunnel size may be unsuitable for vessels with very narrow bow sections or limited internal volume.
Typical Vessels:
Container ships (≥150 m LOA)Cruise linersOffshore supply vesselsLNG carriersRo‑Ro ferries
Decision Guide: Choose if: you need a high‑thrust bow thruster for a large vessel with sufficient electrical generation capacity and enough hull space for a 740 mm tunnel. Avoid if: the ship’s power plant cannot spare 300 kW, the bow geometry is too narrow, or azimuth thrust capability is required.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
MIT-TT-300 stern
unverified
· 300.0 kW
· tunnel thruster
Power (kW)
300
Thrust (kN)
36.0
Diameter (mm)
740
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (36 kN at 300 kW) for effective stern manoeuvring
- Compact 740 mm tunnel diameter fits vessels with limited hull space
- Mitsubishi’s proven reliability and worldwide service network
- Simple mechanical design reduces the number of moving parts and eases routine maintenance
Weaknesses
- Tunnel installation requires a relatively deep hull opening, limiting use on very shallow‑draft ships
- Higher acoustic signature compared with newer azimuth or pump‑jet thrusters
- Fixed thrust direction; cannot provide 360° thrust like an azimuth unit
- Hull resistance penalty when the thruster is not in operation
Typical Vessels:
Medium‑size tankers (up to ~30 000 dwt)Bulk carriers (up to ~40 000 dwt)Offshore supply vesselsFerries and Ro‑Ro shipsCruise ship stern sections
Decision Guide: Choose the MIT‑TT‑300 when you need a reliable, high‑thrust stern thruster for vessels up to medium size, have sufficient hull depth for tunnel installation, and value Mitsubishi’s global support. Avoid it on very shallow‑draft ships, or when 360° thrust capability and minimal acoustic impact are critical, in which case an azimuth pod or pump‑jet may be preferable.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
MIT-TT-400 bow
unverified
· 400.0 kW
· tunnel thruster
Power (kW)
400
Thrust (kN)
48.0
Diameter (mm)
820
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust-to-power ratio (48 kN at 400 kW) for effective sideways force.
- Compact 820 mm tunnel diameter fits into narrow hull sections, preserving cargo space.
- Proven Mitsubishi reliability and service network worldwide.
- Straight‑forward integration with standard vessel control systems.
Weaknesses
- Tunnel geometry leads to higher blade wear and more frequent maintenance than azimuth units.
- Limited thrust vectoring (fixed 90° direction) compared with rotating pod thrusters.
- Noise and vibration can be higher in confined tunnel spaces, requiring acoustic mitigation on passenger vessels.
Typical Vessels:
Container shipBulk carrierGeneral cargo vesselCruise liner (mid‑size)Offshore supply vessel
Decision Guide: Choose if you need a high‑thrust bow thruster that fits within a restricted hull space and can be serviced globally via Mitsubishi’s network. Avoid if the vessel requires full 360° thrust capability, ultra‑low acoustic signature, or minimal maintenance intervals typical of azimuth pod systems.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
MIT-TT-400 stern
unverified
· 400.0 kW
· tunnel thruster
Power (kW)
400
Thrust (kN)
48.0
Diameter (mm)
820
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (48 kN) suitable for large ships and DP operations
- Robust Mitsubishi engineering with proven reliability in marine environments
- Compact footprint compared to azimuth units, fitting into limited stern space
- Direct integration with existing shaft‑line power systems (400 kW)
- Relatively simple control interface – standard PWM or variable frequency drive
Weaknesses
- Significant power demand (400 kW) increases fuel consumption and generator sizing
- Large duct diameter (820 mm) requires substantial hull penetration, affecting structural design
- Maintenance access is confined to the tunnel space, potentially lengthening service intervals
- Higher initial cost than lower‑power tunnel models or basic bow thrusters
- Potential for cavitation at high load if not matched with proper propeller geometry
Typical Vessels:
Container ships (>10 000 gt)Crude oil and product tankersLNG carriersOffshore supply vessels (DP‑2/3)Cruise liners
Decision Guide: Choose if the vessel requires strong lateral thrust for docking, low‑speed maneuvering or dynamic positioning on a large hull and can accommodate the 400 kW power demand. Avoid if the ship is small to medium size, has limited stern space, or if lower power consumption and simpler installation are higher priorities than maximum thrust.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
MIT-TT-500 bow
unverified
· 500.0 kW
· tunnel thruster
Power (kW)
500
Thrust (kN)
60.0
Diameter (mm)
900
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (60 kN at 500 kW) gives strong lateral force for tight docking.
- Robust stainless‑steel tunnel housing resists corrosion in harsh marine environments.
- Integrated variable‑frequency drive allows fine speed control and reduced fuel consumption at low loads.
- Modular design simplifies installation and on‑board maintenance, with quick‑access panels for bearing replacement.
- Proven Mitsubishi brand reputation for reliability and long service intervals.
Weaknesses
- Large duct diameter (900 mm) consumes significant hull space and may limit placement options.
- High power rating requires substantial cooling water flow and a dedicated electrical supply, increasing installation complexity.
- Initial capital cost is higher than comparable low‑power thrusters.
- Spare parts and specialized service expertise can be less readily available in remote ports.
- Noise and vibration levels are higher than some newer ductless (azimuth) designs.
Typical Vessels:
Container ships (>10,000 gt)Cruise linersOffshore supply vesselsLNG carriersLarge Ro‑Ro ferries
Decision Guide: Choose if the vessel requires strong bow thrust for tight port entry, dynamic positioning, or emergency maneuvering on a large hull where space permits a 900 mm tunnel. Avoid if the ship is small, power‑limited, or if hull space constraints make a ducted thruster impractical; consider azimuth or rim‑drive units in those cases.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
MIT-TT-500 stern
unverified
· 500.0 kW
· tunnel thruster
Power (kW)
500
Thrust (kN)
60.0
Diameter (mm)
900
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (≈60 kN) relative to power rating (500 kW)
- Large 900 mm tunnel diameter provides good hydraulic efficiency
- Robust, marine‑grade construction typical of Mitsubishi equipment
- Integrated control interface compatible with most ship bridge systems
- Proven reliability on a range of commercial vessels
Weaknesses
- Significant hull penetration required for installation
- High power demand can increase overall vessel fuel consumption
- Potential cavitation at full‑load conditions if not properly sized to hull form
- Installation and commissioning costs are relatively high
- Limited suitability for small vessels with restricted stern space
Typical Vessels:
Container shipBulk carrierTankerCruise linerOffshore supply vesselLNG/LPG carrier
Decision Guide: Choose if the vessel needs strong stern maneuvering power for tight berthing, dynamic positioning or emergency thrust reversal and has sufficient hull space for a 900 mm tunnel. Avoid on small craft, vessels with strict weight/power limits, or where installation cost outweighs maneuverability benefits.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
MIT-TT-600 bow
unverified
· 600.0 kW
· tunnel thruster
Power (kW)
600
Thrust (kN)
72.0
Diameter (mm)
980
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (72 kN) from a relatively compact tunnel diameter (980 mm)
- Proven reliability and support from Mitsubishi Heavy Industries brand
- Low acoustic signature compared with external azimuth units, beneficial for passenger comfort
- Straight‑forward integration with existing ship control and DP systems
Weaknesses
- Requires hull penetration; installation is more invasive than pod‑type thrusters
- Performance drops in very high sea states or strong cross‑currents compared to azimuth thrusters
- Maintenance of bearings, seals and the tunnel duct can be labour‑intensive
- Limited 360° thrust vectoring – only provides lateral force at the bow
Typical Vessels:
Container shipCruise linerLNG carrierBulk carrierTanker
Decision Guide: Choose if: you need a powerful, space‑efficient bow thruster for a large vessel with existing tunnel provisions and value proven OEM support. Avoid if: the vessel requires omnidirectional thrust, operates frequently in heavy seas, or you wish to minimise hull penetrations.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
MIT-TT-600 stern
unverified
· 600.0 kW
· Tunnel thruster
Power (kW)
600
Thrust (kN)
72.0
Diameter (mm)
980
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (72 kN) relative to its 600 kW power rating gives strong maneuverability.
- Compact tunnel geometry (980 mm diameter) fits within limited hull space, preserving deck area.
- Robust steel construction and integrated water‑cooling system enhance durability in harsh marine environments.
- Direct thrust line at the stern improves control during reverse docking and backing maneuvers.
- Standardized mounting interface simplifies retro‑fit on existing vessels.
Weaknesses
- Tunnel design can generate hull vibration and noise, especially at high load factors.
- Efficiency drops sharply above low ship speeds; not suitable as primary propulsion aid.
- Maintenance requires periodic inspection of bearings, seals and the tunnel liner for cavitation wear.
- Installation demands precise hull penetration and structural reinforcement, increasing dock‑time cost.
- Limited azimuth capability compared with rotating pod or azipod thrusters.
Typical Vessels:
Container ships (up to ~150 m LOA)Bulk carriersProduct tankersCruise vesselsOffshore supply and support vessels
Decision Guide: Choose if you need a high‑thrust, compact stern thruster for vessels that require strong low‑speed maneuverability and have limited hull space. Avoid if the vessel relies on advanced azimuth or podded propulsion for primary thrust, or if vibration and noise are critical concerns.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
MIT-TT-750 bow
unverified
· 750.0 kW
· tunnel thruster
Power (kW)
750
Thrust (kN)
90.0
Diameter (mm)
1100
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (≈90 kN) relative to power rating, enabling effective sideways push on large ships
- Compact 1100 mm duct fits within moderate hull spaces while still delivering strong thrust
- Mitsubishi’s proven reliability and low‑maintenance design with water‑lubricated bearings
- Integrated variable frequency drive allows fine speed control for docking maneuvers
- Modular duct sections simplify installation and future maintenance
Weaknesses
- Fixed‑direction thrust; cannot provide 360° vectoring like azimuth thrusters
- Large duct occupies internal hull volume, potentially reducing cargo or equipment space
- High power draw at full duty can increase fuel consumption for vessels with limited electrical generation capacity
- Installation requires hull penetration and structural reinforcement, adding to build cost
- Noise and vibration levels are higher than some azimuth‑type thrusters, which may affect passenger comfort on cruise ships
Typical Vessels:
Container shipBulk carrierCruise linerOffshore supply vesselRo‑Ro ferry
Decision Guide: Choose if: you need a high‑thrust, reliable bow thruster for vessels up to ~150 m LOA where hull space allows a 1.1 m duct and fixed‑direction thrust is sufficient (e.g., container ships, cruise liners, OSVs). Avoid if: the vessel requires full 360° thrust vectoring, has severe space constraints, or operates under strict noise‑abatement regimes where an azimuth thruster would be preferable.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
MIT-TT-750 stern
unverified
· 750.0 kW
· tunnel thruster
Power (kW)
750
Thrust (kN)
90.0
Diameter (mm)
1100
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (90 kN at 750 kW) gives strong manoeuvring capability
- Compact 1.1 m tunnel diameter fits within typical hull forms without excessive space penalty
- Mitsubishi’s proven reliability and global service network reduce downtime
- Integrated cooling system and low‑vibration design improve operational life
- Standard class approvals (ABS, DNV GL) simplify certification for new builds
Weaknesses
- 750 kW electrical demand requires substantial power plant capacity
- Large hull penetration area may increase structural reinforcement work
- Fixed‑direction thruster; not as versatile as azimuth or pod units for DP applications
- Noise and cavitation can be noticeable at full load, affecting crew comfort
- Higher upfront cost compared with generic low‑power tunnel thrusters
Typical Vessels:
Container shipBulk carrierCrude oil tankerLiquefied gas carrierCruise linerOffshore supply vesselRo‑Ro ferry
Certifications:
ABSDNV GL
Decision Guide: Choose the MIT‑TT‑750 when a large vessel (>30,000 GT) needs strong, reliable stern thrust for docking, undocking and low‑speed manoeuvring, especially where class approvals from ABS or DNV are required. Avoid it on small vessels with limited power budgets, on ships that prefer 360° azimuth thrusters for dynamic positioning, or when hull modifications to accommodate a large tunnel are impractical.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
MIT-TT-800 bow
unverified
· 800.0 kW
· tunnel thruster
Power (kW)
800
Thrust (kN)
96.0
Diameter (mm)
1140
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (96 kN at 800 kW) provides strong low‑speed manoeuvring capability
- Relatively compact tunnel diameter of 1.14 m fits within medium‑size hull openings
- Low acoustic and vibration signature, suitable for passenger‑oriented ships
- Integrated variable‑frequency drive enables precise thrust control and energy efficiency
- Mitsubishi Heavy Industries reputation for durability and long service intervals
Weaknesses
- Large tunnel cross‑section may limit placement in narrow hull sections or affect internal volume
- High power demand can increase fuel consumption during frequent manoeuvring operations
- Installation requires significant structural reinforcement of the hull forepeak
- Spare‑parts distribution and service support are strongest in Asia/EU, weaker in some remote regions
- Potential for cavitation if operated continuously near maximum thrust
Typical Vessels:
Cruise ShipLNG CarrierContainer Vessel (>150,000 DWT)Offshore Supply VesselFerry
Decision Guide: Choose the MIT‑TT‑800 when a large vessel needs strong bow thrust for docking in tight ports, dynamic positioning support, or low‑speed manoeuvring and the hull can accommodate a 1.14 m tunnel. Avoid it on smaller ships with limited power budgets, vessels where hull space is at a premium, or operations where spare‑part logistics are constrained.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
MIT-TT-800 stern
unverified
· 800.0 kW
· high‑power tunnel thruster
Power (kW)
800
Thrust (kN)
96.0
Diameter (mm)
1140
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Delivers a high thrust‑to‑power ratio (96 kN @ 800 kW) suitable for large vessels
- Mitsubishi’s proven reliability and long service life in harsh marine environments
- Optimised blade geometry reduces cavitation and noise during operation
- Integrated variable frequency drive enables fine thrust control and energy efficiency
- Compact tunnel design fits within standard stern tunnel sections on new‑builds
Weaknesses
- Large diameter (1.14 m) requires substantial hull penetration and structural reinforcement
- High power rating leads to significant electrical demand and operating cost
- Installation and routine maintenance can be labour‑intensive due to confined tunnel space
- Initial procurement cost is higher than lower‑power alternatives
- Spare‑part logistics may be slower in remote ports without Mitsubishi service agents
Typical Vessels:
Aframax TankerPanamax Container ShipHandymax Bulk CarrierCruise ShipOffshore Supply Vessel (OSV)DP‑class Workboat
Decision Guide: Choose if: you need high stern thrust for large vessels operating in confined ports, require DP support or emergency backup, and have the electrical infrastructure for an 800 kW unit. Avoid if: vessel size is modest, budget constraints dominate, or hull space cannot accommodate a 1.14 m tunnel.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
MIT-TT-1000 bow
unverified
· 1000.0 kW
· tunnel thruster
Power (kW)
1000
Thrust (kN)
120.0
Diameter (mm)
1300
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust output (≈120 kN) for its size, enabling tight port turns and berthing assistance on large vessels
- Robust Mitsubishi steel housing and impeller design provides long service intervals and resistance to marine fouling
- Integrated control electronics compatible with most ship‑board DP/ANC systems for seamless automation
- Proven track record in commercial and offshore applications, offering high reliability under continuous operation
- Modular installation – the 1300 mm duct fits standard bow thruster openings on new builds and retrofits
Weaknesses
- High power demand (≈1 MW) requires substantial electrical supply and cooling capacity on board
- Physical size and weight may limit installation on smaller vessels or those with restricted hull space
- Tunnel geometry can be more susceptible to cavitation at very high RPMs compared with azimuth thrusters
- Initial capital cost is higher than lower‑power alternatives from less‑known manufacturers
Typical Vessels:
Container ships (≥8,000 TEU)Cruise linersLarge bulk carriersLNG/LPG carriersOffshore support vessels and FPSOs
Decision Guide: Choose if: you need a high‑thrust bow thruster for a vessel >30 000 gt that operates in congested or wind‑exposed ports, and the ship’s power plant can accommodate a ~1 MW electric load. Avoid if: the vessel is small (<10 000 gt) with limited hull space or electrical capacity, or if budget constraints favour lower‑power units.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
MIT-TT-1000 stern
unverified
· 1000.0 kW
· tunnel thruster
Power (kW)
1000
Thrust (kN)
120.0
Diameter (mm)
1300
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (120 kN) relative to power rating, giving excellent manoeuvring force.
- Large 1300 mm duct diameter reduces cavitation and improves hydraulic efficiency.
- Robust stainless‑steel construction typical of Mitsubishi marine equipment, offering long service life.
- Integrated control interface compatible with most ship bridge systems for precise thrust vectoring.
Weaknesses
- High power demand (1 MW) increases fuel consumption when used frequently.
- Large physical size requires substantial hull penetration and reinforcement, limiting installation on smaller ships.
- Installation and maintenance can be more complex due to the larger bearing and seal assemblies.
- Higher initial cost compared with lower‑power thruster options.
Typical Vessels:
Very Large Crude Carrier (VLCC)Container ship (>10,000 TEU)Cruise linerOffshore supply vesselLarge Ro‑Ro ferry
Decision Guide: Choose if the vessel needs high thrust for tight port manoeuvring or dynamic positioning and can accommodate a 1.3 m duct diameter with sufficient power generation. Avoid if the ship has limited stern space, lower power availability, or if cost sensitivity outweighs the need for maximum thrust.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
MIT-TT-1200 bow
unverified
· 1200.0 kW
· tunnel thruster
Power (kW)
1200
Thrust (kN)
144.0
Diameter (mm)
1460
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust output (≈144 kN) relative to installed power, enabling rapid lateral movement.
- Large 1460 mm tunnel diameter reduces cavitation and improves efficiency at high thrust levels.
- Mitsubishi’s proven control electronics integrate with most ship‑automation systems for smooth operation.
- Robust mechanical design suited to continuous use on large tankers, container ships and cruise vessels.
- Standardized mounting dimensions simplify installation in new builds or retrofits.
Weaknesses
- Large physical envelope requires significant hull penetration and internal space.
- High electrical power demand (≈1.2 MW) may necessitate upgrades to ship’s power distribution system.
- Maintenance of the bearing and seal assemblies can be labour‑intensive on vessels with limited dry‑dock windows.
- Noise and vibration levels are higher than smaller thrusters, potentially affecting crew comfort in nearby compartments.
- Initial procurement cost is higher than lower‑power alternatives.
Typical Vessels:
Very Large Crude Carriers (VLCC)Ultra‑Large Container ShipsCruise LinersLNG/LPG carriersOffshore supply vessels
Decision Guide: Choose if the vessel requires high lateral thrust for tight berthing, dynamic positioning or limited tug assistance—especially on ships >30 000 DWT with sufficient power generation capacity. Avoid if hull space is constrained, the ship’s electrical system cannot support ~1.2 MW continuous load, or low‑cost maneuvering solutions are acceptable.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
MIT-TT-1200 stern
unverified
· 1200.0 kW
· Tunnel thruster
Power (kW)
1200
Thrust (kN)
144.0
Diameter (mm)
1460
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (≈144 kN) suitable for large tankers and cruise ships
- Compact tunnel installation saves deck space compared with azimuth pods
- Robust stainless‑steel construction rated for harsh marine environments
- Integrated control system compatible with most DP packages
- Proven track record from Mitsubishi Heavy Industries in global fleets
Weaknesses
- High power demand (≈1 200 kW) increases fuel consumption and generator load
- Fixed‑direction thrust limits maneuverability compared with rotating azimuth units
- Tunnel geometry can be prone to cavitation if not properly sized for hull speed
- Maintenance access is confined within the tunnel, requiring dry‑dock periods
- Initial procurement cost is significant for vessels that may not need such high thrust
Typical Vessels:
Very Large Crude Carrier (VLCC)Ultra‑Large Container Vessel (ULCV)Cruise ShipLNG CarrierOffshore Supply Vessel
Decision Guide: Choose if: the vessel needs a high‑thrust, space‑efficient stern thruster for docking or dynamic positioning and already has hull provisions for a tunnel installation. Avoid if: you prefer full 360° thrust vectoring (azimuth pods), have limited power generation capacity, or the hull cannot accommodate a large tunnel aperture.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
MIT-TT-1500 bow
unverified
· 1500.0 kW
· tunnel thruster
Power (kW)
1500
Thrust (kN)
180.0
Diameter (mm)
1700
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust-to-power ratio (180 kN at 1500 kW) for strong bow assistance
- Large 1.7 m tunnel diameter promotes efficient water flow and low cavitation
- Integrated Mitsubishi control system with variable‑pitch blades enables precise thrust modulation
- Proven reliability on ultra‑large vessels; maintenance access through hull opening is straightforward
- Meets IMO D‑2 type approval, simplifying class certification
Weaknesses
- Large diameter requires significant hull space, limiting installation on smaller ships
- High power demand increases vessel electrical load and may need dedicated generators
- Extensive hull penetration raises construction cost and time
- Higher upfront purchase price compared with lower‑power thrusters
- Spare parts can have longer lead times in remote ports
Typical Vessels:
Container shipBulk carrierTankerCruise linerLNG/LPG carrierOffshore supply vessel
Certifications:
IMO D-2
Decision Guide: Choose if the vessel requires strong bow maneuverability in confined ports, has sufficient hull space for a 1.7 m tunnel and can accommodate the 1500 kW power demand. Avoid on smaller vessels where hull opening size or power availability is limited, or when budget constraints prioritize lower‑cost thrusters.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
MIT-TT-1500 stern
unverified
· 1500.0 kW
· tunnel thruster
Power (kW)
1500
Thrust (kN)
180.0
Diameter (mm)
1700
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (180 kN) suitable for large tankers, container ships and bulk carriers.
- Compact tunnel diameter (1.7 m) allows installation in relatively confined hull spaces compared with larger ducted propellers.
- Robust tunnel design protects the impeller from debris and grounding impacts, extending service life.
Weaknesses
- Large tunnel cross‑section requires significant hull penetration and structural reinforcement.
- 1500 kW power rating leads to high fuel consumption when operated for extended periods.
- Installation at the stern can be complex, especially on vessels with limited aft space or existing steering gear.
Typical Vessels:
Very Large Crude Carrier (VLCC)Ultra‑Large Container Vessel (ULCV)Panamax Bulk CarrierCruise ShipOffshore Supply Vessel
Decision Guide: Choose if: you need a high‑thrust stern thruster for a vessel >30 000 gt, have sufficient aft hull space for a 1.7 m tunnel, and require reliable maneuverability for docking or DP support. Avoid if: the ship is small to medium size, budget constraints limit power consumption, or hull geometry cannot accommodate the tunnel diameter.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
MIT-TT-2000 bow
unverified
· 2000.0 kW
· Tunnel thruster
Power (kW)
2000
Thrust (kN)
240.0
Diameter (mm)
2100
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust output (≈240 kN) relative to its 2 MW power rating, giving strong lateral force for large vessels.
- Compact tunnel layout fits within the hull without protruding external pods, preserving hull hydrodynamics.
- Mitsubishi’s proven control electronics provide smooth, low‑vibration operation and easy integration with ship bridge systems.
- Robust steel tunnel construction offers long service life and resistance to marine corrosion.
- Standardised connection interface simplifies installation and replacement on new builds or retrofits.
Weaknesses
- Large tunnel diameter (≈2.1 m) requires significant hull opening, limiting suitability for vessels with narrow bow sections.
- High power demand (2 MW) increases fuel consumption when used frequently, impacting overall energy efficiency.
- Maintenance of the internal duct and bearing seals can be labour‑intensive compared with simpler azimuth thrusters.
- Potential for cavitation at full‑load conditions if water flow is not optimally managed.
Typical Vessels:
Container shipsCruise linersOffshore supply vesselsLNG carriersBulk carriers
Decision Guide: Choose the MIT‑TT‑2000 when you need maximum bow thrust for a large vessel and have sufficient hull space for a 2.1 m tunnel. Avoid it on smaller ships or where power budget is limited, as its size and energy draw may outweigh the manoeuvring benefit.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
MIT-TT-2000 stern
unverified
· 2000.0 kW
· high‑efficiency tunnel thruster
Power (kW)
2000
Thrust (kN)
240.0
Diameter (mm)
2100
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (≈240 kN @ 2 MW) for large vessels
- Compact tunnel layout fits within narrow hull sections while providing strong lateral force
- Robust steel housing and low‑cavitation blade design reduce wear and maintenance intervals
- Integrated control electronics compatible with most DP and ship‑handling systems
Weaknesses
- Large 2.1 m tunnel diameter may limit installation on vessels with restricted hull space
- High power demand (2 MW) increases auxiliary load and fuel consumption during operation
- Access for routine inspection can be difficult due to the enclosed tunnel geometry
- Initial procurement cost is higher than lower‑power alternatives
Typical Vessels:
Container shipCrude oil tankerProduct tankerCruise linerOffshore supply vessel
Decision Guide: Choose if: you need a high‑thrust stern thruster for vessels >80 m beam, DP or tight port manoeuvring, and have sufficient hull space for a 2.1 m tunnel. Avoid if: the vessel’s hull form cannot accommodate the tunnel diameter, power budget is limited, or a lower‑cost, lower‑power solution suffices.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
MIT-TT-2500 bow
unverified
· 2500.0 kW
· tunnel thruster
Power (kW)
2500
Thrust (kN)
300.0
Diameter (mm)
2500
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust-to-power ratio (≈120 N/kW) suitable for mega‑vessels
- Optimised tunnel geometry reduces hydrodynamic losses and vibration
- Integrated variable frequency drive enables precise thrust control
- Mitsubishi Heavy Industries reputation for durability and long service life
- Standardised mounting kit simplifies installation on new builds
Weaknesses
- Large 2.5 m tunnel diameter limits use in vessels with narrow hull sections
- High electrical power demand (≈2.5 MW) requires robust shipboard supply
- Access for routine inspection and blade replacement can be confined within the tunnel
- Potential cavitation noise at full‑load conditions
- Initial capital cost is higher than smaller, lower‑power alternatives
Typical Vessels:
Container ships (≥8 000 TEU)Cruise linersLNG carriersVery large crude carriers (VLCC) and Aframax tankersOffshore supply vessels with dynamic positioning
Decision Guide: Choose if the vessel requires high bow‑thruster thrust for safe port entry, tight berthing or DP operations on a large hull where space permits a 2.5 m tunnel. Avoid if the ship’s beam or internal layout cannot accommodate the tunnel size, or if power generation capacity is limited.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
MIT-TT-2500 stern
unverified
· 2500.0 kW
· tunnel thruster
Power (kW)
2500
Thrust (kN)
300.0
Diameter (mm)
2500
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (≈300 kN) suitable for large vessels
- Compact footprint compared with azimuth units of similar power
- Robust, low‑maintenance design typical of Mitsubishi marine equipment
- Integrated control interface compatible with most ship bridge systems
Weaknesses
- High electrical power demand (≈2.5 MW) requiring substantial generator capacity
- Fixed thrust direction; cannot rotate like a bow/azimuth thruster
- Installation requires a large tunnel aperture (≈2.5 m diameter)
- Potential for cavitation at very high RPMs if not properly sized
Typical Vessels:
Container shipBulk carrierCrude oil tankerLiquefied gas carrierCruise liner
Decision Guide: Choose if the vessel needs a very high‑thrust stern thruster for port entry/exit, DP assistance or emergency maneuvering and has sufficient onboard power. Avoid if space for a large tunnel is limited, if a rotating (azimuth) thrust direction is required, or if the ship’s power plant cannot support ~2.5 MW dedicated to a single thruster.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
MIT-TT-3000 bow
unverified
· 3000.0 kW
· tunnel thruster
Power (kW)
3000
Thrust (kN)
360.0
Diameter (mm)
2900
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (360 kN) suitable for mega‑vessels and DP operations
- Robust, marine‑grade construction typical of Mitsubishi equipment
- Integrated control interface compatible with most bridge systems
- Large tunnel diameter provides efficient water flow and reduced cavitation
Weaknesses
- Requires substantial hull penetration and internal space due to 2.9 m tunnel size
- High power demand (3 MW) leads to increased fuel consumption and electrical load
- Installation and commissioning costs are relatively high
- Spare‑parts logistics may be longer for this specific large‑size model
Typical Vessels:
Ultra‑large container shipsVery large crude carriers (VLCC) / Aframax tankersCruise liners (>150,000 GT)LNG carriers and other high‑value cargo vesselsOffshore supply vessels with dynamic positioning
Decision Guide: Choose if the vessel requires very high bow thrust for port entry/exit of mega‑ships or for reliable DP operation, and hull space is available for a large tunnel. Avoid on smaller ships where the size, power demand and cost outweigh the maneuverability benefit.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
MIT-TT-3000 stern
unverified
· 3000.0 kW
Power (kW)
3000
Thrust (kN)
360.0
Diameter (mm)
2900
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (≈360 kN) suitable for mega‑size tankers and container ships
- Compact tunnel integration minimizes above‑deck clutter
- Mitsubishi’s reputation for reliability and long service life
- Designed for direct coupling with electric drive systems, enabling precise control
- Low acoustic signature compared with conventional azimuth thrusters
Weaknesses
- Large diameter (≈2.9 m) limits installation on vessels with restricted hull space
- High power rating (3 MW) leads to significant electrical demand and operating cost
- Hull penetration required for tunnel installation increases structural complexity
- Maintenance of bearings and seals can be intensive due to high loads
- Initial procurement cost is relatively high
Typical Vessels:
Very Large Crude Carrier (VLCC)Ultra‑Large Container Ship (ULCS)LNG CarrierBulk Carrier (>200 kt)
Decision Guide: Choose if: you need maximum low‑speed thrust for a very large vessel, have sufficient hull space for a ~3 m tunnel, and require precise electric control for DP or tight port manoeuvring. Avoid if: the ship is smaller, budget constraints are critical, or retrofitting space is limited.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
MIT-TT-3500 bow
unverified
· 3500.0 kW
· Tunnel thruster
Power (kW)
3500
Thrust (kN)
420.0
Diameter (mm)
3300
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (420 kN) relative to power rating (3500 kW), giving strong manoeuvring capability
- Large duct diameter reduces cavitation and improves hydraulic efficiency
- Robust MHI construction with proven reliability on mega‑vessels
- Global after‑sales support and spare‑parts network
- Can be integrated with DP control systems for dynamic positioning
Weaknesses
- Large physical size (3.3 m diameter) requires significant hull reinforcement and space
- High power demand increases fuel consumption when used frequently
- Installation cost is substantial due to duct fabrication and alignment work
- Effectiveness diminishes on very high‑speed vessels where wash is overrun by forward motion
- Potential for increased noise/vibration if not properly isolated
Typical Vessels:
Cruise shipLNG carrierOffshore supply vesselLarge container shipBulk carrierTankers requiring precise port entry
Certifications:
IMO Type Approval (D‑2)
Decision Guide: Choose the MIT‑TT‑3500 when a large vessel needs maximum bow thrust for tight‑port manoeuvring or DP operations and hull space allows a 3.3 m duct. Avoid it on smaller ships, vessels with limited bow volume, or projects where budget and power consumption are primary constraints.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
MIT-TT-3500 stern
unverified
· 3500.0 kW
· tunnel thruster
Power (kW)
3500
Thrust (kN)
420.0
Diameter (mm)
3300
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (≈420 kN) suitable for mega‑size ships
- Robust water‑lubricated bearing design reduces wear and maintenance intervals
- Compact tunnel diameter (3.3 m) provides strong thrust while fitting within typical hull sections
- Integrated control electronics compatible with most modern bridge navigation systems
Weaknesses
- Large hull penetration required, increasing structural complexity and potential for leakage if not installed correctly
- High power rating leads to greater auxiliary engine load and fuel consumption during use
- Noise and vibration levels can be significant at full power, requiring additional acoustic mitigation on passenger vessels
- Installation and alignment are time‑consuming, impacting dry‑dock schedules
Typical Vessels:
VLCC / Suezmax tankersUltra Large Container Vessels (ULCV)LNG carriersCruise shipsLarge offshore support vessels
Decision Guide: Choose if you need a stern thruster that can generate >400 kN thrust for very large, deep‑draught vessels and you have the hull space for a 3.3 m tunnel. Avoid if vessel size is modest, where a lower‑power thruster would suffice, or if minimizing installation complexity and noise is a priority.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
MIT-TT-4000 bow
unverified
· 4000.0 kW
· high‑power tunnel thruster
Power (kW)
4000
Thrust (kN)
480.0
Diameter (mm)
3700
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (480 kN) suitable for mega‑vessels and DP operations
- Large tunnel diameter reduces cavitation and improves efficiency at low speeds
- Mitsubishi’s proven reliability and global after‑sales support network
- Integrated control electronics compatible with most ship bridge systems
- Designed for easy retro‑fit into existing hull structures of large ships
Weaknesses
- Large physical footprint (3.7 m tunnel) limits installation to vessels with ample bow space
- High power demand (4 MW) increases fuel consumption and electrical system sizing
- Installation and maintenance require specialised tooling and skilled personnel
- Higher capital cost compared with smaller‑capacity thrusters
- Potential for increased vibration if not properly aligned during installation
Typical Vessels:
VLCC / ULCC crude carriersLNG carriers (Q‑Fit, Q‑Max)Large cruise shipsOffshore supply & anchor handling tug supply vesselsVery large container or bulk carriers (>150 kt)
Decision Guide: Choose if you need >400 kN of bow thrust for a vessel over 150 kt, have sufficient hull volume for a 3.7 m tunnel, and require proven OEM support for DP or tight‑port manoeuvring. Avoid if the ship is smaller, has limited bow space, or budget constraints make a lower‑power thruster more appropriate.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
MIT-TT-4000 stern
unverified
· 4000.0 kW
· tunnel thruster
Power (kW)
4000
Thrust (kN)
480.0
Diameter (mm)
3700
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust output (480 kN) for its power rating, enabling rapid stopping and tight docking maneuvers.
- Compact tunnel diameter (3.7 m) allows installation in limited hull space while still providing large thrust.
- Integrated variable‑frequency drive provides precise speed control and energy efficiency.
- Mitsubishi’s proven reliability record with long service intervals on mega‑vessels.
- Low‑cavitation blade design reduces noise and wear.
Weaknesses
- Requires a substantial hull opening (≈3.7 m) and associated structural reinforcement, increasing construction complexity.
- High electrical power demand (4 MW) may strain shipboard power distribution on smaller vessels.
- Bearing and seal maintenance are intensive due to the large rotating mass.
- Size limits installation to stern positions on ships with sufficient beam; not suitable for bow use on many designs.
- Capital cost is higher than lower‑power thrusters or azimuth units of comparable thrust.
Typical Vessels:
Cruise shipLNG carrierVery large container vesselOffshore supply vesselFPSO
Decision Guide: Choose if: you need very high thrust for a large vessel, have sufficient hull space for a 3.7 m tunnel, and require precise low‑speed maneuvering or DP support. Avoid if: the ship’s power plant cannot accommodate a 4 MW load, hull modifications are prohibitive, or an azimuth thruster would provide better all‑direction thrust at lower cost.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
MIT-TT-4500 bow
unverified
· 4500.0 kW
· high‑thrust tunnel thruster
Power (kW)
4500
Thrust (kN)
540.0
Diameter (mm)
4100
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust output (≈540 kN) suitable for mega‑vessels and DP operations
- Robust Mitsubishi hydraulic drive with proven reliability in harsh marine environments
- Compact duct diameter relative to thrust, allowing installation on vessels with limited hull space
- Integrated control system compatible with most ship bridge automation packages
- Low acoustic signature compared with conventional propeller‑type thrusters
Weaknesses
- Large power demand (≈4.5 MW) requiring substantial electrical or hydraulic supply capacity
- Installation requires significant hull penetration and reinforcement, increasing dock‑time cost
- Maintenance access can be limited due to the size of the duct and internal components
- Higher initial capital cost than smaller tunnel thrusters or basic azimuth units
- Weight and structural loads may affect vessel stability calculations
Typical Vessels:
Ultra‑large container shipsCrude oil tankers (VLCC, Suezmax)LNG carriersCruise linersOffshore supply vessels with DP capability
Certifications:
IMO Type ApprovalDNV GL Class approval
Decision Guide: Choose if the vessel requires very high bow thrust for safe port entry, dynamic positioning or emergency maneuvering and has sufficient power generation capacity. Avoid on smaller ships where a lower‑power thruster would meet requirements, or when hull modifications for a large tunnel duct are impractical.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
MIT-TT-4500 stern
unverified
· 4500.0 kW
· tunnel thruster
Power (kW)
4500
Thrust (kN)
540.0
Diameter (mm)
4100
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (≈540 kN) suitable for mega‑vessels and heavy‑load docking operations
- Robust tunnel housing provides good protection against debris and hull impacts
- Integrated control system compatible with most ship bridge consoles
- Relatively low acoustic signature compared with open propeller azimuth units
- Proven reliability on long‑range tankers and cruise ships
Weaknesses
- Large hull penetration (≈4.1 m diameter) limits installation options and requires extensive structural reinforcement
- High power demand (≈4.5 MW) increases fuel consumption and electrical load
- Maintenance access can be difficult due to the size of the tunnel housing
- Less flexible thrust direction than a 360° azimuth thruster, limiting station‑keeping in extreme weather
- Potential for cavitation at very high loading conditions
Typical Vessels:
Very Large Crude Carrier (VLCC)LNG carrierCruise shipOffshore supply vesselLarge container ship
Decision Guide: Choose if the vessel requires maximum stern thrust for safe berthing of very large ships, has sufficient hull space for a 4.1 m tunnel, and values a simple, rugged design with proven class‑approval history. Avoid if you need full 360° thrust vectoring, have limited installation envelope, or wish to minimise power consumption.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
MIT-TT-5000 bow
unverified
· 5000.0 kW
· Tunnel thruster
Power (kW)
5000
Thrust (kN)
600.0
Diameter (mm)
4500
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust output (≈600 kN) suitable for mega‑vessels and DP operations
- Large duct diameter reduces cavitation and improves efficiency at high power levels
- Robust, proven tunnel design tolerates harsh marine environments and impact loads
- Integrated control electronics compatible with most ship bridge/DP systems
Weaknesses
- Large hull penetration (≈4.5 m) limits installation to vessels with sufficient beam
- High electrical power demand (5 MW) requires substantial onboard generation capacity
- Installation and maintenance are more complex than smaller thrusters or azimuth units
- Weight and structural reinforcement requirements increase overall ship weight
Typical Vessels:
VLCC / ULCCLarge LNG carriersUltra‑large container ships (≥15,000 TEU)Cruise liners (>200 m length)Offshore support vessels with DP requirements
Decision Guide: Choose if: you need very high bow thrust for a vessel >150 m beam, require reliable low‑cavitation performance, and have sufficient power generation capacity. Avoid if: the ship’s beam or internal layout cannot accommodate a 4.5 m tunnel, power supply is limited, or an azimuth/azipod solution would provide better overall propulsion efficiency.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
MIT-TT-5000 stern
unverified
· 5000.0 kW
· tunnel thruster
Power (kW)
5000
Thrust (kN)
600.0
Diameter (mm)
4500
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust output (≈600 kN) suitable for large ships
- Compact installation compared with external azimuth pods
- Integrated control system compatible with DP and bow‑thruster coordination
- Robust duct design for marine fouling resistance
Weaknesses
- High electrical power demand (5 MW) requiring substantial onboard generation capacity
- Large duct diameter may limit hull form options or increase draft
- Maintenance of internal propeller and bearings can be labour‑intensive
- Potential for increased noise and vibration at full power
Typical Vessels:
Very Large Crude Carrier (VLCC)Ultra Large Container Vessel (ULCV)Cruise shipOffshore supply vesselLarge Ro‑Ro ferry
Decision Guide: Choose if: you need maximum thrust for a very large vessel, have sufficient onboard power generation, and prefer an internal thruster to preserve hull lines. Avoid if: the ship’s draft or hull geometry cannot accommodate a 4.5 m duct, power plant capacity is limited, or low‑noise operation is a primary requirement.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Nakashima Thruster
44
NK-TT-50 bow
unverified
· 50.0 kW
· tunnel thruster
Power (kW)
50
Thrust (kN)
6.0
Diameter (mm)
540
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Compact 540 mm tunnel diameter fits vessels with limited hull space
- 6 kN thrust at modest 50 kW power provides good thrust‑to‑power ratio for small‑to‑medium ships
- Bow‑only design simplifies installation and integration with existing steering systems
- Low noise and vibration typical of tunnel thrusters improves crew comfort
Weaknesses
- Maximum thrust (6 kN) may be insufficient for large tankers or cruise ships requiring higher maneuvering forces
- Limited to bow installations; no stern version offered in this model line
- Performance can degrade in heavy sea states where tunnel flow is disrupted
- No published certifications, so class approval may require additional documentation
Typical Vessels:
Coastal Container VesselsFerriesOffshore Supply BoatsWorkboatsSmall Cruise Ships
Decision Guide: Choose if: you need a compact, moderate‑power bow thruster for vessels up to ~150 m LOA operating in confined ports or requiring DP assistance on small platforms. Avoid if: the vessel demands high thrust (>10 kN), stern maneuverability, or must meet specific class approvals that are not yet documented for this model.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NK-TT-50 stern
unverified
· 50.0 kW
· tunnel thruster
Power (kW)
50
Thrust (kN)
6.0
Diameter (mm)
540
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Compact 540 mm duct diameter fits in limited hull space
- Relatively low power demand (50 kW) reduces fuel consumption
- Provides sufficient thrust (6 kN) for fine‑scale maneuvering on small to medium vessels
- Simple installation at the stern with standard tunnel mounting
Weaknesses
- Maximum thrust may be inadequate for large tankers or high‑speed ships requiring stronger bow/stern assistance
- Limited to low‑power applications; not suitable where high‑capacity dynamic positioning is needed
- No published data on cavitation resistance or noise levels, which may affect crew comfort
Typical Vessels:
Coastal tankerOffshore supply vesselFerry (up to 150 m length)Small bulk carrierWorkboat / tug‑assist craft
Decision Guide: Choose if: the vessel needs a modest stern thrust boost for port manoeuvring, has limited power availability, and space constraints favour a compact tunnel unit. Avoid if: high thrust ( >10 kN) or high‑speed dynamic positioning is required, or if certification to specific class societies is mandatory.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
NK-TT-75 bow
unverified
· 75.0 kW
· tunnel thruster
Power (kW)
75
Thrust (kN)
9.0
Diameter (mm)
560
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Compact 560 mm tunnel fits well in limited bow space
- Good thrust‑to‑power ratio (9 kN @ 75 kW) for vessels up to ~30 kt DWT
- Proven, low‑maintenance design with simple shaft‑driven motor
- Low acoustic signature compared with larger azimuth units
Weaknesses
- Fixed thrust direction – no 360° steering capability
- Maximum thrust (9 kN) may be insufficient for large vessels or strong currents
- Performance can degrade in heavy seas due to water ingress into tunnel
- Higher power consumption per kN of thrust than some modern azimuth models
Typical Vessels:
Feeder container shipsCoastal tankersBulk carriers up to ~30 ktOffshore supply vesselsCruise ship tenders
Decision Guide: Choose if: you need a reliable, space‑saving bow thruster for vessels up to ~30 kt DWT with moderate maneuvering requirements and prefer a proven tunnel design. Avoid if: you require higher thrust levels, azimuth steering, or operation in extreme wind/current conditions where an azimuth unit would be more effective.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NK-TT-75 stern
unverified
· 75.0 kW
· tunnel thruster
Power (kW)
75
Thrust (kN)
9.0
Diameter (mm)
560
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (9 kN from 75 kW) for its size
- Compact 560 mm tunnel fits vessels with limited hull space
- Proven Nakashima reliability and low maintenance sealed bearing design
- Good cavitation resistance at typical maneuvering speeds
- Straightforward integration with existing ship electrical systems
Weaknesses
- Fixed‑pitch blades give less efficient reverse thrust compared to azimuth units
- Higher power consumption than smaller thrusters on low‑displacement vessels
- Installation requires a dedicated stern tunnel and structural reinforcement
- Noise and vibration levels are higher than some ducted or pump‑jet alternatives
- Limited directional control – cannot vector thrust like a pod or azimuth thruster
Typical Vessels:
Handymax bulk carrierProduct tanker (up to ~30,000 DWT)Container feederOffshore supply vesselCruise ship (mid‑size) for stern assistance
Decision Guide: Choose if you need a reliable, compact stern thruster with solid thrust output for medium‑sized vessels and have space for a fixed tunnel. Avoid if the vessel requires full 360° thrust vectoring, ultra‑low power consumption, or operates in noise‑sensitive environments where an azimuth pod would be preferable.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NK-TT-100 bow
unverified
· 100.0 kW
· tunnel thruster
Power (kW)
100
Thrust (kN)
12.0
Diameter (mm)
580
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio for its size (12 kN @ 100 kW)
- Relatively small tunnel diameter (580 mm) fits vessels with limited hull space
- Straight‑through flow design reduces cavitation and noise compared with some azimuth units
- Integrated control electronics compatible with most ship bridge consoles
Weaknesses
- Maximum thrust may be insufficient for larger tankers or high‑speed container ships
- Installation requires a through‑hull opening, limiting retrofit options on some hull forms
- Power demand (100 kW) can be significant for vessels with limited auxiliary generation capacity
- Maintenance of bearings and seals is required at regular intervals to prevent water ingress
Typical Vessels:
Offshore supply vesselCoastal ferrySmall bulk carrier (≤5,000 DWT)Feeder container shipPatrol or research vessel
Decision Guide: Choose if you need a compact bow thruster that provides moderate thrust for vessels up to about 5,000 DWT and have sufficient auxiliary power. Avoid if the vessel requires higher thrust levels (e.g., large tankers or high‑speed ships) or if hull geometry does not allow a through‑hull tunnel installation.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
NK-TT-100 stern
unverified
· 100.0 kW
· tunnel thruster
Power (kW)
100
Thrust (kN)
12.0
Diameter (mm)
580
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (≈0.12 kN/kW) for its size
- Compact 580 mm tunnel diameter fits into limited hull spaces
- Robust fixed‑pitch propeller reduces mechanical complexity
- Relatively low installation cost compared with azimuth units
Weaknesses
- Fixed thrust direction limits flexibility versus azimuth thrusters
- Potential for cavitation at high RPM in shallow water
- Maintenance of bearings and seals can be labour‑intensive
- Maximum thrust (12 kN) may be insufficient for large tankers or heavy‑load vessels
Typical Vessels:
Offshore supply vesselCoastal container shipFerrySmall bulk carrierDP0/DP1 platform support vessel
Decision Guide: Choose if: you need a cost‑effective, space‑saving stern thruster delivering up to 12 kN for vessels under ~30 kt and operating mainly in ports or calm waters. Avoid if: the ship requires higher thrust levels, full 360° thrust vectoring, or will operate frequently in deep‑water high‑speed maneuvers where cavitation risk is critical.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NK-TT-150 bow
unverified
· 150.0 kW
· tunnel thruster
Power (kW)
150
Thrust (kN)
18.0
Diameter (mm)
620
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (18 kN) relative to its modest 150 kW power rating
- Compact 620 mm tunnel diameter fits ships with limited hull space at the bow
- Standardized tunnel design simplifies installation and routine maintenance
- Proven reliability – no recorded model‑specific failures in available data
- Direct integration with ship’s existing electrical system (150 kW three‑phase)
Weaknesses
- Fixed‑pitch ducted propeller offers limited thrust reversal compared with azimuthing units
- Power consumption is higher than newer low‑speed, high‑efficiency thrusters of similar thrust
- Hull penetration required; structural reinforcement adds installation cost and time
- Noise and vibration levels are typical for conventional tunnel designs, not optimized for ultra‑quiet operation
Typical Vessels:
Container ships (up to ~30 000 dwt)Bulk carriers (up to ~25 000 dwt)General cargo vesselsOffshore supply vesselsFerries and cruise ship auxiliaries requiring bow maneuverability
Decision Guide: Choose if: you need a reliable, compact bow thruster delivering around 18 kN thrust for vessels up to ~30 000 dwt and you have limited space at the bow. Avoid if: you require higher thrust per kilowatt, reversible thrust without gear changes, or ultra‑low noise performance; in those cases consider azimuthing pod thrusters or newer low‑speed ducted designs.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NK-TT-150 stern
unverified
· 150.0 kW
· tunnel thruster
Power (kW)
150
Thrust (kN)
18.0
Diameter (mm)
620
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (18 kN from 150 kW) improves docking performance
- Robust tunnel housing reduces cavitation and protects the propeller
- Relatively compact for its thrust rating, fitting typical stern tunnels of 620 mm diameter
- Japanese engineering reputation for reliability and long service life
- Straightforward integration with conventional helm‑control or DP systems
Weaknesses
- Large tunnel diameter (620 mm) may limit installation in vessels with narrow stern sections
- Fixed thrust direction; no azimuth capability for sideways thrust without additional steering gear
- Higher vibration and noise compared with modern ducted‑propeller or pod units
- Maintenance access can be difficult because the unit is located within a hull tunnel
- Power consumption higher than newer electric pod thrusters of comparable thrust
Typical Vessels:
Offshore Supply VesselCruise ShipContainer ShipBulk CarrierRo‑Ro Ferry
Decision Guide: Choose if: you need a proven, high‑thrust tunnel thruster for a vessel that can accommodate a 620 mm stern tunnel and you value reliability over azimuth flexibility. Avoid if: hull space is limited, you require 360° thrust vectoring, or you are targeting the lowest possible power consumption with newer pod technologies.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NK-TT-200 bow
unverified
· 200.0 kW
· tunnel thruster
Power (kW)
200
Thrust (kN)
24.0
Diameter (mm)
660
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (24 kN from 200 kW) improves manoeuvrability without excessive power demand.
- Relatively compact tunnel diameter (660 mm) fits into tighter hull spaces, useful for vessels with limited bow volume.
- Robust cast‑iron tunnel housing and stainless‑steel impeller are suited to harsh marine environments and corrosion resistance.
- Standard three‑phase electrical interface simplifies integration with existing ship power systems.
Weaknesses
- Fixed bow installation limits flexibility; not suitable for retrofits requiring stern thrust.
- Maximum thrust of 24 kN may be insufficient for very large tankers or cruise ships that need >30 kN for safe docking.
- Tunnel geometry adds hull resistance when the thruster is idle, potentially increasing fuel consumption at cruising speed.
- Requires periodic inspection and cleaning of the tunnel lining to prevent fouling and corrosion.
Typical Vessels:
ContainerBulk CarrierTankerOffshore Support VesselCruise Ship
Decision Guide: Choose if: you need a reliable, high‑thrust bow thruster for vessels up to ~30 000 gt where space is limited and power availability matches a 200 kW unit. Avoid if: the ship requires higher thrust levels, stern manoeuvring capability, or you wish to minimise hull resistance during transit.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NK-TT-200 stern
unverified
· 200.0 kW
· Tunnel thruster
Power (kW)
200
Thrust (kN)
24.0
Diameter (mm)
660
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (24 kN) for its power rating, giving good manoeuvring force.
- Compact hull penetration – the 660 mm tunnel fits within typical stern sections without excessive structural modification.
- Robust steel housing and internal impeller designed for continuous marine service, resulting in low routine maintenance.
- Standardised electrical interface allows integration with vessel’s existing power distribution and VFD control systems.
Weaknesses
- Effectiveness drops sharply at speeds above ~5 kn; not suitable as the sole propulsion aid for high‑speed vessels.
- Potential cavitation and noise in shallow water or when operating near the surface.
- Hull penetration creates a permanent opening that must be sealed against corrosion and flooding.
- Limited thrust vectoring – provides only transverse force, requiring complementary bow thrusters for full DP capability.
Typical Vessels:
Container ships (up to ~150 m LOA)Cruise linersOffshore supply vesselsFerriesGeneral cargo vessels
Decision Guide: Choose if the vessel needs strong low‑speed transverse thrust for berthing, un‑berthing or emergency manoeuvring and has limited beam space for a larger tunnel. Avoid if the ship operates primarily at higher speeds, requires full dynamic positioning with multi‑directional thrust, or where thruster noise and cavitation are critical constraints.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NK-TT-250 bow
unverified
· 250.0 kW
· tunnel thruster
Power (kW)
250
Thrust (kN)
30.0
Diameter (mm)
700
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (30 kN) relative to its power rating (250 kW)
- Compact 700 mm tunnel diameter fits vessels with limited hull space
- Bow location provides effective lateral control during docking and low‑speed operations
- Standardized motor size simplifies integration with existing ship electrical systems
Weaknesses
- Requires a dedicated shaft tunnel, limiting installation to new builds or major retrofits
- Power demand of 250 kW can be significant for smaller vessels with limited generator capacity
- Typical tunnel thrusters generate noise and vibration that may need mitigation measures
Typical Vessels:
Offshore supply vesselMedium‑size container ship (up to ~10,000 gt)Cruise ferryMultipurpose bulk carrier
Decision Guide: Choose if: you need a mid‑range thrust capability for vessels up to about 10,000 gt and have sufficient hull space for a 700 mm tunnel. Avoid if: the vessel’s power plant cannot spare 250 kW or if hull modifications for a tunnel are impractical.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NK-TT-250 stern
unverified
· 250.0 kW
· tunnel thruster
Power (kW)
250
Thrust (kN)
30.0
Diameter (mm)
700
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (30 kN at 250 kW) for strong manoeuvring capability
- Robust tunnel construction that protects the propeller from debris and grounding impacts
- Compact installation envelope compared with azimuth pods of similar power
- Proven reliability in long‑haul commercial vessels
Weaknesses
- Large duct diameter (700 mm) may limit fit in narrow hull sections or retrofits
- Higher shaft line maintenance due to tunnel bearings and seals
- Fixed thrust direction; cannot provide 360° thrust like azimuth units
- Power demand of 250 kW can be significant for vessels with limited auxiliary generation
Typical Vessels:
Container shipBulk carrierProduct tankerCruise liner (stern maneuvering)Offshore supply vessel
Decision Guide: Choose if you need a high‑thrust, reliable stern thruster for DP or tight‑port docking and have sufficient hull space for a 700 mm tunnel. Avoid if the vessel has severe space constraints, limited auxiliary power, or requires omnidirectional thrust that only an azimuth unit can provide.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
NK-TT-300 bow
unverified
· 300.0 kW
· tunnel thruster
Power (kW)
300
Thrust (kN)
36.0
Diameter (mm)
740
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (36 kN at 300 kW) for its size
- Compact 740 mm tunnel diameter fits medium‑size hulls without major structural modifications
- Integrated variable‑frequency drive provides smooth, fine‑controlled thrust
- Robust stainless‑steel ducting reduces corrosion in harsh marine environments
- Low vibration and noise levels compared with some azimuth thrusters
Weaknesses
- Limited to bow installation; not optimized for stern use where flow conditions differ
- Water ingress can increase maintenance intervals on the motor and bearings
- Maximum thrust (36 kN) may be insufficient for very large vessels (>30,000 DWT) or high‑speed DP operations
- Standard fixed‑direction nozzle limits lateral thrust vectoring without additional steering gear
Typical Vessels:
Container ships (up to ~20,000 DWT)Bulk carriers (up to ~25,000 DWT)General cargo vesselsOffshore supply and support vessels
Decision Guide: Choose if: you need a reliable bow thruster for medium‑size vessels requiring strong low‑speed maneuverability, have limited hull space, and prefer a proven tunnel design with integrated drive. Avoid if: the vessel demands higher thrust levels, stern‑thruster capability, or advanced azimuth steering without extra hardware.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
NK-TT-300 stern
unverified
· 300.0 kW
· tunnel thruster
Power (kW)
300
Thrust (kN)
36.0
Diameter (mm)
740
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (36 kN @ 300 kW) for its size class
- Compact tunnel footprint fits within standard hull sections without major structural modifications
- Robust marine‑grade steel construction with proven corrosion resistance
- Relatively low acoustic signature, beneficial for noise‑sensitive operations
- Straightforward installation and integration with existing ship control systems
Weaknesses
- Limited directional flexibility compared with azimuth or pod thrusters
- Potential cavitation at high load or shallow water depths
- Requires regular bearing lubrication and tunnel lining inspection
- Space inside the hull must accommodate a large diameter tunnel, affecting cargo space on smaller ships
- Performance drops noticeably in very strong currents or wind when used alone
Typical Vessels:
Container ship (up to ~10 000 gt)Bulk carrier (up to ~15 000 gt)Product tankerOffshore supply vesselMid‑size cruise ferry
Decision Guide: Choose if: you need a reliable, high‑thrust stern thruster for vessels up to medium size where hull space allows a 740 mm tunnel and where low noise is important. Avoid if: the vessel requires full 360° thrust vectoring, operates in extreme shallow water prone to cavitation, or has severe space constraints that preclude a large tunnel.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NK-TT-400 bow
unverified
· 400.0 kW
· Tunnel thruster
Power (kW)
400
Thrust (kN)
48.0
Diameter (mm)
820
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (48 kN) for its power rating, improving port manoeuvrability
- Compact tunnel footprint fits within limited hull space
- Robust marine‑grade construction typical of Nakashima products
- Relatively low acoustic signature compared with external propeller thrusters
Weaknesses
- Fixed thrust direction; cannot provide 360° vectoring like azimuth units
- Potential for cavitation at high load due to tunnel geometry
- Requires hull penetration and internal space for the tunnel, increasing installation complexity
- Maintenance of bearings and seals can be labour‑intensive
Typical Vessels:
Container ships (up to ~150 m LOA)General cargo vesselsOffshore supply vesselsFerriesCruise ships (mid‑size)
Decision Guide: Choose if: you need strong, reliable bow thrust for medium‑sized vessels with limited hull space and prefer a proven tunnel design. Avoid if: you require omnidirectional thrust, higher thrust-to-power ratios, or have severe draft constraints that limit tunnel installation.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NK-TT-400 stern
unverified
· 400.0 kW
· tunnel thruster
Power (kW)
400
Thrust (kN)
48.0
Diameter (mm)
820
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (48 kN @ 400 kW) for its size
- Compact 820 mm tunnel diameter fits into limited hull spaces
- Integrated variable‑frequency drive enables fine thrust control
- Low acoustic signature compared with external propeller units
- Standardized mounting arrangement simplifies installation on new builds
Weaknesses
- Maximum thrust (48 kN) may be insufficient for very large tankers or cruise ships
- Hull penetration required; tunnel liner wear can increase maintenance intervals
- Single‑unit design offers limited redundancy if a failure occurs
- Potential cavitation at high RPMs in shallow water conditions
- Performance data not widely published, making comparative sizing harder
Typical Vessels:
Container ships (up to ~8,000 TEU)General cargo vesselsOffshore supply & support vesselsFerries and Ro‑Ro shipsMid‑size cruise liners
Decision Guide: Choose if: you need a reliable stern thruster for vessels up to ~30,000 gt where hull space is at a premium and a thrust of ~48 kN meets maneuvering requirements. Avoid if: the vessel requires >60 kN thrust, high redundancy (dual‑unit layout), or operates frequently in very shallow water where cavitation risk is critical.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NK-TT-500 bow
unverified
· 500.0 kW
· tunnel thruster
Power (kW)
500
Thrust (kN)
60.0
Diameter (mm)
900
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (60 kN) relative to power rating (500 kW)
- Large 900 mm tunnel diameter reduces cavitation and improves propulsive efficiency
- Designed for bow installation on large vessels, providing strong low‑speed maneuverability
Weaknesses
- Physical size (900 mm tunnel) may restrict installation in smaller hulls or retrofit projects
- Higher power demand (500 kW) increases electrical system requirements and operating cost
- Limited market presence of the Nakashima brand could affect spare‑part availability
Typical Vessels:
Container shipBulk carrierCruise linerOffshore supply vesselLNG carrier
Decision Guide: Choose if: you need a high‑thrust bow thruster for a large vessel with sufficient space and power capacity, especially where low cavitation is critical. Avoid if: the vessel has limited hull volume for a 900 mm tunnel or operates on a lower power budget.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
NK-TT-500 stern
unverified
· 500.0 kW
· tunnel thruster
Power (kW)
500
Thrust (kN)
60.0
Diameter (mm)
900
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (60 kN) relative to its 500 kW power rating provides strong bow‑/stern‑side force for docking and DP operations.
- Large 900 mm tunnel diameter reduces cavitation risk and improves hydraulic efficiency compared with smaller units.
- Compact footprint in the hull allows installation on vessels where space is limited, especially at the stern.
- Proven ducted design offers predictable performance across a wide range of sea states.
Weaknesses
- 500 kW electrical demand requires substantial shipboard power distribution and cooling infrastructure.
- The 900 mm tunnel size may necessitate significant hull penetration work and structural reinforcement during retro‑fit.
- Limited market presence compared with major thruster brands can affect spare‑part availability and long‑term support.
- Fixed‑direction thrust limits flexibility relative to azimuth or pod‑type thrusters for vessels requiring 360° maneuverability.
Typical Vessels:
Container shipBulk carrierProduct tankerCruise vesselOffshore supply vessel
Decision Guide: Choose if the vessel needs a high‑thrust, space‑efficient stern thruster and has sufficient electrical capacity; avoid if you require omnidirectional thrust, have severe weight/space constraints for retrofits, or prefer a brand with broader global service networks.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
NK-TT-600 bow
unverified
· 600.0 kW
· hydraulic tunnel thruster
Power (kW)
600
Thrust (kN)
72.0
Diameter (mm)
980
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (72 kN) suitable for vessels over 30 000 gt
- Relatively compact tunnel diameter (~1 m) compared with similar‑power units
- Robust hydraulic drive known for durability in harsh marine environments
- Integrated bow placement improves maneuverability during docking and DP operations
Weaknesses
- Large tunnel size may limit installation on vessels with restricted hull space
- High power (600 kW) results in greater fuel consumption when used frequently
- Hydraulic system requires regular oil maintenance and leak monitoring
- Installation and alignment are complex, often needing dry‑dock periods
Typical Vessels:
Container shipCruise linerLNG carrierOffshore supply vesselLarge bulk carrier
Decision Guide: Choose if: you need >70 kN bow thrust for vessels ≥30 000 gt, have sufficient hull volume for a ~1 m tunnel, and require proven hydraulic reliability. Avoid if: hull space is constrained, power budget is limited, or you prefer electric‑drive thrusters with lower maintenance overhead.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NK-TT-600 stern
unverified
· 600.0 kW
· tunnel thruster
Power (kW)
600
Thrust (kN)
72.0
Diameter (mm)
980
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (72 kN) relative to its power rating, giving strong maneuvering force
- Large 980 mm tunnel diameter reduces cavitation risk and improves hydraulic efficiency
- Compact stern‑mount design suited for vessels with limited aft space
- Robust construction typical of Japanese marine equipment manufacturers
Weaknesses
- 600 kW power demand requires substantial electrical supply and cooling infrastructure
- Installation may be complex due to integration of the tunnel into the hull structure
- Potentially higher acquisition and lifecycle cost compared with lower‑power competitors
- Spare‑part availability could be limited if the brand has a small global dealer network
Typical Vessels:
Crude oil tankerContainer shipCruise linerOffshore supply vesselDP‑class platform support vessel
Decision Guide: Choose if: you need a high‑thrust stern thruster for vessels >30,000 gt and have the electrical capacity to feed 600 kW; you value reduced cavitation and robust build quality. Avoid if: budget constraints limit power rating, vessel size cannot accommodate a ~1 m tunnel, or you prefer a widely supported brand with extensive service networks.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
NK-TT-750 bow
unverified
· 750.0 kW
· high‑power tunnel thruster
Power (kW)
750
Thrust (kN)
90.0
Diameter (mm)
1100
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (90 kN) suitable for DP‑class and deep‑draft ships
- Large 1.1 m duct provides efficient water flow and reduced cavitation
- Integrated control electronics compatible with most bridge systems
- Robust construction typical of Nakashima’s marine‑grade alloys
Weaknesses
- Significant installation space required in the bow tunnel
- High electrical power demand (750 kW) may exceed smaller ship generators
- Larger moving parts can increase maintenance intervals compared with compact azimuth units
- Weight and structural reinforcement needs are higher than low‑power alternatives
Typical Vessels:
Container ships (>8,000 TEU)Cruise linersLarge LNG carriersOffshore supply vessels with DP‑1/DP‑2 capabilityBulk carriers over 150 kt
Decision Guide: Choose if the vessel needs strong bow thrust for dynamic positioning, tight‑port maneuvering or to compensate for a long hull form. Avoid on smaller ships where space, power budget or weight are limiting factors, or when a compact azimuth thruster would provide sufficient performance at lower cost.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
NK-TT-750 stern
unverified
· 750.0 kW
· hydraulic tunnel thruster
Power (kW)
750
Thrust (kN)
90.0
Diameter (mm)
1100
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (90 kN) for its power rating enables strong lateral force on large ships
- Large 1.1 m duct diameter promotes efficient water flow and reduces pressure loss
- Stern placement improves reverse‑maneuvering control during docking and undocking
- Robust construction typical of Nakashima units offers long service intervals
Weaknesses
- 750 kW power demand requires substantial electrical or hydraulic supply capacity
- Physical size of the 1.1 m tunnel may limit installation in vessels with restricted stern space
- Potential for cavitation at high load if not matched with proper propeller design
- Maintenance access can be challenging on stern‑mounted units compared with bow installations
Typical Vessels:
Very Large Crude Carrier (VLCC)Container ship (>8,000 TEU)Cruise linerOffshore supply vesselRo‑Ro ferry
Decision Guide: Choose if the vessel requires high lateral thrust for safe docking in confined ports or needs stern assistance for dynamic positioning. Avoid on smaller ships where power budget or space constraints make a lower‑rated thruster more appropriate.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
NK-TT-800 bow
unverified
· 800.0 kW
· tunnel thruster
Power (kW)
800
Thrust (kN)
96.0
Diameter (mm)
1140
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust-to-power ratio (96 kN at 800 kW) suitable for large ships requiring strong bow assistance
- Robust tunnel construction protects the propeller and motor from debris and grounding impacts
- Relatively low acoustic signature compared with exposed azimuth units, beneficial for noise‑sensitive ports
- Standardized duct size (1140 mm) fits many existing hull retrofits without major redesign
Weaknesses
- Large duct diameter reduces usable hull volume and may limit placement on smaller vessels
- Tunnel geometry can cause higher hydrodynamic resistance, lowering overall efficiency at low speeds
- Maintenance access to bearings and motor requires removal of the tunnel cover, increasing downtime
- Less thrust vectoring flexibility than a 360° azimuth thruster
Typical Vessels:
Very Large Crude Carriers (VLCC)Ultra‑Large Container Ships (ULCS)Cruise ships >150 m LOAOffshore supply vessels with DP capability
Decision Guide: Choose if the vessel needs maximum bow thrust for tight port entries, has sufficient hull space for a 1.14 m tunnel, and values a protected propeller arrangement. Avoid if hull length or beam constraints prevent a large duct, or if full‑circle thrust vectoring is required for dynamic positioning.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NK-TT-800 stern
unverified
· 800.0 kW
· high‑power tunnel thruster
Power (kW)
800
Thrust (kN)
96.0
Diameter (mm)
1140
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust-to-power ratio (96 kN at 800 kW) enables tight turning circles and rapid docking maneuvers.
- Large 1.14 m duct diameter promotes efficient water flow and reduces cavitation risk.
- Sealed motor and stainless‑steel housing give low maintenance requirements in corrosive sea water.
- Compact stern footprint fits ships with limited aft space while still delivering high thrust.
- Japanese engineering reputation for reliability and long service life.
Weaknesses
- 800 kW electrical demand may exceed existing generator capacity on older vessels, requiring upgrades.
- The 1.14 m duct size can be a constraint for retrofits in hulls with limited aft clearance.
- Tunnel thrusters are susceptible to marine growth; regular cleaning is required to maintain performance.
- Higher noise and vibration levels compared with azimuth or pod thrusters at similar thrust levels.
- Spare‑part supply primarily through Japanese channels, which can lengthen lead times for non‑local shipyards.
Typical Vessels:
Crude Oil TankerProduct TankerContainer Ship (≥8 000 TEU)Cruise ShipOffshore Supply Vessel
Decision Guide: Choose the NK‑TT‑800 when you need maximum thrust for a large vessel with sufficient electrical capacity and space for a 1.14 m tunnel, especially where low maintenance and proven durability are priorities. Avoid it on smaller ships with limited aft volume, on vessels sensitive to noise/vibration, or where rapid spare‑part availability is critical.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
NK-TT-1000 bow
unverified
· 1000.0 kW
· tunnel thruster
Power (kW)
1000
Thrust (kN)
120.0
Diameter (mm)
1300
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (≈120 kN) suitable for ships >30 000 dwt
- Large 1.3 m tunnel diameter provides efficient water flow and reduced cavitation
- 1000 kW power rating gives rapid response for dynamic positioning or emergency maneuvers
- Robust construction typical of bow‑mounted thrusters, tolerant to debris ingress
Weaknesses
- High electrical power demand (≈1 MW) may exceed the capacity of smaller vessels' generators
- Large tunnel size requires significant hull penetration and structural reinforcement
- Installation and maintenance are more complex compared with compact azimuth units
- Potential for increased noise and vibration at full power if not properly isolated
Typical Vessels:
Very Large Crude Carriers (VLCC)Ultra‑Large Container Ships (ULCS)Cruise shipsOffshore supply vesselsRo‑Ro ferries with high maneuverability needs
Decision Guide: Choose if the vessel demands maximum low‑speed thrust for safe docking in tight ports, requires reliable dynamic positioning support, or operates under heavy wind/current conditions. Avoid if the ship has limited electrical generation capacity, restricted hull space for a large tunnel, or if a smaller azimuth thruster would meet maneuverability requirements at lower cost.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NK-TT-1000 stern
unverified
· 1000.0 kW
· Tunnel thruster
Power (kW)
1000
Thrust (kN)
120.0
Diameter (mm)
1300
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (120 kN) relative to its 1 MW power rating
- Compact tunnel geometry fits within limited hull space at the stern
- Robust, low‑maintenance construction typical of Nakashima marine equipment
- Integrated control interface compatible with most ship bridge systems
Weaknesses
- Significant power demand (≈1 MW) increases fuel consumption when used frequently
- Hull penetration required for installation can be complex and costly
- Potential cavitation at full‑load conditions, especially in shallow water
- Limited to fixed‑direction thrust; not as versatile as azimuth or pod thrusters
Typical Vessels:
Container shipCrude oil tankerLNG carrierCruise linerOffshore supply vessel
Decision Guide: Choose if: you need a proven, high‑thrust tunnel thruster for a large vessel with limited stern space and can accommodate the power draw. Avoid if: you require 360° thrust vectoring, low‑power operation, or want to minimise hull modifications.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NK-TT-1200 bow
unverified
· 1200.0 kW
· tunnel thruster
Power (kW)
1200
Thrust (kN)
144.0
Diameter (mm)
1460
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust output (144 kN) suitable for vessels >80 000 gt
- Compact tunnel geometry fits within standard bow bulb dimensions
- Integrated variable‑frequency drive allows fine thrust control
- Robust stainless‑steel housing rated for continuous seawater exposure
Weaknesses
- High power demand (1.2 MW) requires substantial onboard electrical capacity
- Large diameter (1.46 m) may limit installation on vessels with restricted bow space
- Tunnel design can be prone to cavitation at high RPM, increasing noise and wear
- Maintenance access is confined; routine inspection of bearings and seals can be time‑consuming
Typical Vessels:
Container ships (≥8 000 teu)Crude oil / product tankers (≥70 000 dwt)LNG carriersCruise linersOffshore supply vessels
Decision Guide: Choose if the vessel requires high bow‑side thrust for port entry, dynamic positioning or tight berth handling and has sufficient electrical generation capacity. Avoid on smaller ships where space is limited or power budgets cannot accommodate a 1.2 MW motor.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NK-TT-1200 stern
unverified
· 1200.0 kW
· tunnel thruster
Power (kW)
1200
Thrust (kN)
144.0
Diameter (mm)
1460
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (144 kN) relative to power consumption provides strong manoeuvring force.
- Compact tunnel diameter (1460 mm) allows installation in moderate hull sections without excessive structural enlargement.
- Robust steel housing and sealed bearings are suited for harsh marine environments and long service intervals.
- Designed for integration with vessel control systems, including dynamic positioning (DP) packages.
Weaknesses
- Requires significant hull penetration and reinforcement at the stern, increasing installation complexity.
- High power demand (1200 kW) leads to notable fuel consumption when operated continuously.
- Tunnel geometry can limit effectiveness in very shallow water or when heavy fouling occurs.
- Noise and vibration levels are generally higher than those of azimuth thrusters.
Typical Vessels:
Container shipBulk carrierTankerCruise linerOffshore supply vessel
Decision Guide: Choose the NK‑TT‑1200 when a vessel needs high thrust for stern‑side manoeuvring, has sufficient hull space for a 1.46 m tunnel, and requires reliable integration with DP systems. Avoid if hull modifications are prohibitive, shallow‑water operation is dominant, or lower noise/vibration solutions are prioritized.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
NK-TT-1500 bow
unverified
· 1500.0 kW
· tunnel thruster
Power (kW)
1500
Thrust (kN)
180.0
Diameter (mm)
1700
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (180 kN) suitable for vessels >200 m LOA and DP2/DP3 operations
- Compact tunnel layout frees deck space compared with external azimuth units
- Robust, marine‑grade housing tolerates harsh port environments
- Integrated control electronics compatible with most ship bridge systems
Weaknesses
- High power demand (1 500 kW) increases fuel consumption and generator load
- Large tunnel diameter may limit installation in vessels with narrow hull sections or restricted under‑deck space
- Maintenance of bearings and seals can be intensive on high‑load units
- Potential for cavitation at full‑power operation, requiring careful propeller design
Typical Vessels:
Container shipCrude oil tankerLNG carrierCruise linerOffshore supply vessel
Decision Guide: Choose if you need >180 kN bow thrust for large vessels, require DP2/DP3 capability, and have sufficient generator capacity. Avoid if the ship’s hull geometry cannot accommodate a 1.7 m tunnel or if power budget is limited.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NK-TT-1500 stern
unverified
· 1500.0 kW
· tunnel thruster
Power (kW)
1500
Thrust (kN)
180.0
Diameter (mm)
1700
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (180 kN) suitable for very large ships
- Large 1.7 m duct diameter reduces cavitation and improves efficiency
- Robust tunnel design tolerates harsh marine environments
- Provides strong low‑speed maneuvering for DP or emergency situations
Weaknesses
- Very high power rating (1500 kW) leads to significant energy consumption
- Large physical size requires substantial hull penetration and structural reinforcement
- Installation and commissioning are complex and costly
- Higher maintenance demands due to larger bearings and seals
Typical Vessels:
Very Large Crude Carrier (VLCC)Ultra‑Large Container Ship (ULCS)Cruise linerOffshore supply vesselLNG carrier
Decision Guide: Choose if the vessel needs high thrust for precise docking, dynamic positioning or emergency maneuvering and has sufficient hull space and power budget. Avoid on smaller ships, vessels with limited stern room, or where lower‑power thrusters meet operational requirements.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
NK-TT-2000 bow
unverified
· 2000.0 kW
· tunnel thruster
Power (kW)
2000
Thrust (kN)
240.0
Diameter (mm)
2100
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (≈240 kN) suitable for vessels >150 kt deadweight
- 2000 kW electric drive provides strong, controllable push/pull forces
- Large 2100 mm tunnel diameter reduces flow blockage and improves efficiency at low speeds
- Robust design typical of Nakashima’s marine‑grade steel construction
Weaknesses
- Large tunnel size occupies significant hull volume and may affect hydrodynamic resistance when not in use
- Higher installation cost and longer lead time compared with smaller thrusters
- Maintenance of large bearing assemblies can be more demanding
- Potential for cavitation at high thrust settings if water flow is restricted
Typical Vessels:
Very Large Crude Carrier (VLCC)Ultra‑Large Container Ship (ULCS)Cruise shipOffshore supply vessel (OSV) with high maneuverability needs
Decision Guide: Choose if: you need >200 kN bow thrust for a large vessel where precise low‑speed handling is critical, and hull space allows a 2.1 m tunnel. Avoid if: the ship’s design limits tunnel diameter, or a lower‑power thruster would meet maneuvering requirements at reduced cost and weight.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
NK-TT-2000 stern
unverified
· 2000.0 kW
· tunnel thruster
Power (kW)
2000
Thrust (kN)
240.0
Diameter (mm)
2100
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (240 kN) suitable for large tankers and bulk carriers
- Large 2100 mm duct diameter reduces cavitation risk at high power levels
- Integrated control electronics compatible with most DP systems
- Robust stainless‑steel housing designed for harsh marine environments
Weaknesses
- High installed power (2 MW) leads to significant fuel consumption when used continuously
- Large duct size may limit installation options on vessels with restricted hull space
- Requires dedicated cooling and ventilation systems due to high motor output
- Higher upfront cost compared with lower‑power thruster alternatives
Typical Vessels:
Crude oil tankerLNG carrierContainer ship (>150 kTEU)Bulk carrier (>200 kt)
Decision Guide: Choose if: you need a stern thruster with very high thrust for DP‑1/DP‑2 operations on large vessels, and hull space allows a 2.1 m duct. Avoid if: vessel size or power budget cannot accommodate the 2 MW motor and associated cooling infrastructure.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NK-TT-2500 bow
unverified
· 2500.0 kW
· High-power tunnel thruster
Power (kW)
2500
Thrust (kN)
300.0
Diameter (mm)
2500
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (300 kN) for a bow installation, enabling tight port turns and berthing assistance.
- Compact tunnel footprint fits within standard hull sections without excessive external protrusion.
- Robust marine‑grade construction typical of Nakashima products, offering long service intervals.
- Integrated control interface compatible with most modern ship bridge systems.
- Suitable for vessels requiring high maneuvering forces at low speeds (e.g., large container ships, cruise liners).
Weaknesses
- Large tunnel aperture adds hull resistance and may affect fuel efficiency when the thruster is not in use.
- Maintenance access can be limited; dry‑docking is often required for major overhauls.
- Potential cavitation at full power in shallow water, requiring careful operational monitoring.
- Higher initial procurement and installation cost compared with smaller or azimuth units.
- Requires dedicated electrical supply (≈2.5 MW) and cooling infrastructure.
Typical Vessels:
Container shipCruise linerBulk carrierLNG/LPG carrierOffshore support vessel
Decision Guide: Choose if the vessel needs strong bow thrust for maneuvering in confined ports, has sufficient hull space for a 2.5 m tunnel, and can accommodate the electrical power demand. Avoid if fuel‑efficiency at cruise speed is paramount, hull form cannot tolerate the tunnel opening, or budget constraints limit high‑power thruster installation.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NK-TT-2500 stern
unverified
· 2500.0 kW
· tunnel thruster
Power (kW)
2500
Thrust (kN)
300.0
Diameter (mm)
2500
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust output (≈300 kN) for its size, giving strong lateral force for large ships
- Large 2.5 m duct diameter reduces cavitation risk and improves efficiency at high power levels
- Robust steel construction designed for continuous DP operation and harsh marine environments
- Integrated stern mounting minimizes hull penetration points compared with side‑mounted units
- Available with variable frequency drive (VFD) for fine thrust control and energy savings
Weaknesses
- High electrical power demand (≈2 500 kW) requires substantial onboard generation capacity
- Large physical envelope occupies significant stern space, limiting installation on smaller hulls
- Installation complexity – requires precise alignment of the duct and shaft seals at the stern
- Noise and vibration levels can be higher than smaller thrusters, may need additional mitigation
- Maintenance access is more difficult in confined stern compartments
Typical Vessels:
Container ship (≥8 000 TEU)Crude oil or product tanker (>80 000 dwt)LNG carrierCruise linerOffshore supply vessel / DP‑2/3 platform support
Decision Guide: Choose if: you need high lateral thrust for a large vessel that performs frequent docking, undocking or dynamic positioning and have sufficient electrical generation capacity. Avoid if: the ship is small to medium size, power budget is limited, or stern space cannot accommodate a 2.5 m ducted unit.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NK-TT-3000 bow
unverified
· 3000.0 kW
· Tunnel thruster
Power (kW)
3000
Thrust (kN)
360.0
Diameter (mm)
2900
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust output (360 kN) for its size, enabling effective bow assistance on large ships
- Compact tunnel design fits within standard hull sections without external protrusion
- Robust construction with proven Nakashima reliability and low vibration levels
- Integrated control electronics compatible with most ship bridge systems
- Suitable for DP‑assisted vessels where additional thrust reserve is required
Weaknesses
- High electrical power demand (3 MW) requiring substantial generator capacity
- Hull penetration and structural reinforcement increase installation complexity and cost
- Limited azimuth capability compared with pod or azipod thrusters, reducing maneuverability at very low speeds
- Maintenance of bearings, seals and cooling system can be intensive on heavily used vessels
- Noise and vibration may need additional mitigation in passenger‑focused ships
Typical Vessels:
Cruise shipLNG carrierOffshore supply vesselLarge container shipBulk carrier (>200 kDWT)
Decision Guide: Choose the NK‑TT‑3000 when you need a high thrust bow thruster for large vessels with ample power generation and prefer a tunnel solution that is compact, robust and relatively low cost. Avoid it on ships where 360° thrust vectoring, minimal hull penetration, or very low‑speed maneuverability are critical, such as DP‑only vessels that already use azimuth pods.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
NK-TT-3000 stern
unverified
· 3000.0 kW
· tunnel thruster
Power (kW)
3000
Thrust (kN)
360.0
Diameter (mm)
2900
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (360 kN) suitable for large tankers and container ships
- Large 2.9 m duct diameter reduces cavitation and improves efficiency at high power
- Robust steel tunnel construction with integrated cooling for continuous operation
- Simple mechanical layout results in relatively low maintenance compared with azimuth pods
Weaknesses
- Significant hull penetration required, affecting structural integrity and watertight subdivision
- High electrical demand (≈3 MW) increases ship power plant sizing and operating cost
- Large installation space limits use on smaller vessels or retrofits with limited stern clearance
- Potential for increased noise and vibration at full power
Typical Vessels:
Very Large Crude Carrier (VLCC)Ultra‑Large Container Vessel (ULCV)LNG carrierCruise shipOffshore supply vessel with DP capability
Decision Guide: Choose if the vessel needs maximum low‑speed thrust for port entry/exit, dynamic positioning or emergency maneuvering and has sufficient stern space and power plant capacity. Avoid if the ship is size‑restricted, power‑limited, or if a more compact azimuth thruster would meet the manoeuvring requirements.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
NK-TT-3500 bow
unverified
· 3500.0 kW
· tunnel thruster
Power (kW)
3500
Thrust (kN)
420.0
Diameter (mm)
3300
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (420 kN) suitable for large vessels and tight port operations
- Large tunnel diameter (3300 mm) provides efficient water flow and reduced cavitation risk
- 3500 kW motor offers strong response for dynamic positioning or emergency maneuvers
- Bow location improves turning moment when docking or undocking
Weaknesses
- Large hull penetration required, increasing structural complexity and potential leakage points
- High power rating leads to greater fuel consumption and higher operating costs
- Physical size may limit installation on vessels with restricted bow space
- Maintenance access can be difficult due to the large tunnel dimensions
Typical Vessels:
Container shipCruise linerLNG carrierOffshore supply vesselLarge bulk carrier
Decision Guide: Choose if: you need maximum bow thrust for a vessel >150 m LOA operating in confined ports or requiring DP capability. Avoid if: hull space is limited, power budget is tight, or the vessel’s maneuvering requirements are modest.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
NK-TT-3500 stern
unverified
· 3500.0 kW
· high‑power tunnel thruster
Power (kW)
3500
Thrust (kN)
420.0
Diameter (mm)
3300
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (420 kN) enables effective sideways control on large ships
- Large 3.3 m tunnel diameter provides good flow efficiency and reduced cavitation risk at design speed
- 3500 kW power rating matches the needs of high‑displacement vessels with limited maneuvering space
- Robust stern mounting allows integration with existing hull structures without extensive modifications
Weaknesses
- High electrical demand (3.5 MW) requires substantial onboard power generation capacity
- Large tunnel aperture may reduce available cargo space or require significant hull penetration
- Maintenance access can be difficult due to size and location at the stern
- Potential for increased vibration and noise transmission to crew areas
Typical Vessels:
Container shipBulk carrierVery Large Crude Carrier (VLCC)Ro‑Ro ferryOffshore supply vessel
Decision Guide: Choose if: you need a stern thruster with >400 kN thrust for vessels over 150,000 dwt, have sufficient onboard power generation, and require precise low‑speed handling in confined ports. Avoid if: the vessel has limited power margin, space constraints at the stern, or operates primarily at high speed where a smaller thruster would suffice.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
NK-TT-4000 bow
unverified
· 4000.0 kW
· high‑power tunnel thruster
Power (kW)
4000
Thrust (kN)
480.0
Diameter (mm)
3700
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (480 kN) suitable for ships >150 m LOA
- Robust tunnel construction with easy access for inspection and maintenance
- Integrated control electronics compatible with most bridge automation systems
- Proven reliability in harsh marine environments
Weaknesses
- Large duct diameter (3.7 m) limits installation to vessels with sufficient hull space
- High electrical power demand (4 MW) requires substantial onboard generation capacity
- Installation and alignment are complex, increasing dock‑time and cost
- Potential for cavitation if operated at very high RPM in shallow water
Typical Vessels:
Cruise shipsLNG carriersLarge container vesselsOffshore supply vesselsRo‑Ro ferries
Decision Guide: Choose if: you need maximum bow thrust for a vessel >150 m with ample hull space and sufficient power generation. Avoid if: the ship’s design cannot accommodate a 3.7 m tunnel or power plant is limited, or where lower‑cost, smaller thrusters meet maneuverability requirements.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
NK-TT-4000 stern
unverified
· 4000.0 kW
· tunnel thruster
Power (kW)
4000
Thrust (kN)
480.0
Diameter (mm)
3700
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust output (≈480 kN) suitable for large ships and DP operations
- Compact tunnel installation saves deck space compared with external azimuth units
- Robust, marine‑grade construction typical of Nakashima products
- Integrated control interface compatible with most ship bridge systems
Weaknesses
- High electrical power demand (≈4 MW) requiring substantial generator capacity
- Hull penetration for the tunnel can increase corrosion‑maintenance workload
- Potential cavitation and noise at full‑load conditions
- Limited effectiveness in very shallow water due to draft of the tunnel
Typical Vessels:
Cruise ShipLNG CarrierOffshore Supply VesselLarge Container ShipRo‑Ro Ferry
Decision Guide: Choose if: you need a powerful stern thruster for DP or tight‑berth manoeuvring on large vessels and have sufficient onboard power. Avoid if: the vessel is small, power‑limited, or operates primarily in shallow drafts where tunnel installation is problematic.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
NK-TT-4500 bow
unverified
· 4500.0 kW
· tunnel thruster
Power (kW)
4500
Thrust (kN)
540.0
Diameter (mm)
4100
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (540 kN) suitable for vessels >200 000 dwt or DP‑class ships
- Large tunnel diameter reduces cavitation and improves efficiency at high power levels
- Direct integration with ship’s main power system (4500 kW) enables strong, responsive control
Weaknesses
- Large physical size limits installation to vessels with sufficient hull volume in the bow
- High power demand increases fuel consumption and may require upgraded electrical distribution
- Maintenance access can be challenging due to the size of the tunnel and associated bearings
Typical Vessels:
Very Large Crude Carrier (VLCC)Ultra‑Large Container Vessel (ULCV)Cruise ShipOffshore Supply Vessel (OSV) with DP requirements
Decision Guide: Choose if: you need >500 kN bow thrust for a vessel of 200 000+ dwt, operate in confined ports or require dynamic positioning. Avoid if: hull space is limited, power generation capacity cannot support 4.5 MW per thruster, or the vessel’s maneuvering requirements are modest.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NK-TT-4500 stern
unverified
· 4500.0 kW
· high‑power tunnel thruster
Power (kW)
4500
Thrust (kN)
540.0
Diameter (mm)
4100
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (≈540 kN) enables rapid stopping and precise positioning of mega‑vessels
- Large 4.1 m duct provides efficient water flow with reduced cavitation risk
- Robust, marine‑grade steel construction suited for continuous DP operation
- Integrated cooling system handles the 4500 kW power rating without overheating
Weaknesses
- High electrical demand (≈4500 kW) may require dedicated generator capacity
- Large hull penetration increases installation complexity and potential leakage points
- Maintenance access is limited due to size of duct and propeller assembly
- Spare‑part lead times can be long for such a specialised, high‑capacity unit
Typical Vessels:
VLCCULCCLarge LNG carrierCruise ship (>150 k GT)Offshore supply vessel with DP2/DP3 capability
Decision Guide: Choose if: you need maximum stern thrust for a vessel >150 000 DWT, operate in confined ports or require high‑precision DP maneuvering. Avoid if: the ship’s power plant cannot support a 4.5 MW thruster, hull space is limited, or operating costs must be kept low.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NK-TT-5000 bow
unverified
· 5000.0 kW
· high-power tunnel thruster
Power (kW)
5000
Thrust (kN)
600.0
Diameter (mm)
4500
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (≈600 kN) suitable for mega‑size ships and dynamic positioning
- Large tunnel diameter provides high flow rates and efficient thrust generation
- Designed for integration with advanced ship‑control systems
- Robust construction typical of Nakashima’s marine thrusters
Weaknesses
- Physical size (4.5 m tunnel) limits installation to vessels with ample hull space
- High electrical power demand (≈5 MW) may exceed the budget of smaller ships
- Potential for cavitation at extreme loads, requiring careful operation
- Maintenance access can be more complex due to the large tunnel geometry
Typical Vessels:
Ultra‑Large Container ShipVery Large Crude CarrierLNG CarrierCruise ShipOffshore Support Vessel
Decision Guide: Choose if the vessel requires very high bow thrust for port entry, tight maneuvering or DP operations and has sufficient hull volume and power supply for a 5 MW thruster. Avoid if the ship is size‑restricted, power‑limited, or if lower thrust solutions would meet operational needs at reduced cost.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NK-TT-5000 stern
unverified
· 5000.0 kW
· tunnel thruster
Power (kW)
5000
Thrust (kN)
600.0
Diameter (mm)
4500
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High power (5 MW) provides strong thrust suitable for vessels >100 000 dwt
- Large 4.5 m duct diameter yields efficient water flow and high thrust per kW
- Stern installation improves yaw control during docking and DP operations
- Integrated variable‑frequency drive allows fine speed regulation
- Robust design for continuous operation in harsh marine environments
Weaknesses
- 4.5 m diameter requires significant hull penetration and structural reinforcement
- High electrical demand may exceed existing ship power distribution without upgrades
- Tunnel geometry can be prone to duct wear and corrosion, increasing maintenance intervals
- Large size limits installation on smaller vessels or those with restricted stern space
- Noise and vibration levels higher than azimuthal pod‑type thrusters at full power
Typical Vessels:
Very Large Crude Carrier (VLCC)Ultra Large Container Vessel (ULCV)Cruise ShipOffshore Supply VesselLNG Carrier
Decision Guide: Choose if: you need a high‑thrust stern thruster for vessels >100 000 dwt, require precise DP capability, and have sufficient electrical generation capacity. Avoid if: vessel size or hull form cannot accommodate a 4.5 m tunnel, power plant is limited, or lower noise/vibration solutions are prioritized.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
Niigata
44
NIG-TT-50 bow
unverified
· 50.0 kW
· tunnel thruster
Power (kW)
50
Thrust (kN)
6.0
Diameter (mm)
540
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (6 kN @ 50 kW) for its size
- Compact 540 mm tunnel diameter fits limited hull space
- Proven Niigata Marine reliability and low maintenance design
- Quiet operation compared with external propeller thrusters
Weaknesses
- Maximum thrust of 6 kN may be insufficient for large vessels or high‑wind conditions
- Limited to 50 kW, restricting use on high‑power DP systems
- Potential cavitation at full power in shallow water
- Access for routine inspection can be tight in very cramped bow sections
Typical Vessels:
Offshore supply vesselWorkboat / Utility craftCoastal tanker (≤2,000 GT)Small container feederFerry or passenger craft up to ~3,000 GT
Decision Guide: Choose if you need a compact, reliable bow thruster delivering moderate thrust for vessels under about 3,000 GT with limited power availability. Avoid if the vessel requires higher thrust (>10 kN), higher power (>100 kW) or operates in extreme weather where larger DP‑grade thrusters are mandatory.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
NIG-TT-50 stern
unverified
· 50.0 kW
· tunnel thruster
Power (kW)
50
Thrust (kN)
6.0
Diameter (mm)
540
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Compact 540 mm duct diameter fits tight hull spaces
- Low power consumption (50 kW) reduces fuel and electrical load
- Simple, robust design with few moving parts for high reliability
- Easy retro‑fit on existing vessels due to standard tunnel mounting
Weaknesses
- Maximum thrust of 6 kN may be insufficient for large or high‑speed ships
- Limited cavitation resistance at full power in shallow water
- Noise and vibration can be noticeable during prolonged use
- No built‑in redundancy; failure disables stern maneuvering
Typical Vessels:
Coastal cargo vesselsFerries (up to ~5,000 GT)Offshore supply boatsSmall tankers and bulk carriersWorkboats / utility craft
Decision Guide: Choose if you need a space‑saving, low‑power stern thruster for vessels up to medium size where modest thrust (≈6 kN) is adequate for docking and low‑speed manoeuvring. Avoid if the vessel requires high thrust (>10 kN), operates in deep‑water dynamic positioning, or demands built‑in redundancy.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NIG-TT-75 bow
unverified
· 75.0 kW
· tunnel thruster
Power (kW)
75
Thrust (kN)
9.0
Diameter (mm)
560
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Compact hull penetration – fits in limited bow space on medium‑size vessels
- Integrated motor‑pump unit simplifies installation and maintenance
- Relatively quiet operation compared with open‑propeller designs
- Proven Niigata Marine reliability and service support
Weaknesses
- Maximum thrust (9 kN) may be insufficient for large tankers or high‑power tugs
- Tunnel geometry can be prone to cavitation at very high RPMs
- Requires hull modification; not a plug‑and‑play retrofit for all ships
- Less versatile than azimuth thrusters for 360° thrust vectoring
Typical Vessels:
Offshore supply vesselCoastal ferrySmall container ship (up to ~5,000 GT)Research / survey vesselCoastal tanker
Decision Guide: Choose if you need a cost‑effective, space‑saving bow thruster delivering up to 9 kN for vessels under about 5,000 GT that operate mainly at low speeds in ports or during DP‑assisted operations. Avoid if the vessel requires higher thrust levels, full 360° maneuverability, or if hull modifications are not feasible.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NIG-TT-75 stern
unverified
· 75.0 kW
· tunnel thruster
Power (kW)
75
Thrust (kN)
9.0
Diameter (mm)
560
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Compact 560 mm tunnel diameter fits into moderate hull spaces
- Good power‑to‑thrust ratio (75 kW for 9 kN) keeps fuel consumption modest
- Proven Niigata Marine brand reputation for durability and low maintenance
- Straightforward installation in the stern tunnel with standard mounting provisions
Weaknesses
- Maximum thrust of 9 kN may be insufficient for large vessels or extreme weather conditions
- Tunnel geometry can add hull resistance when the thruster is not in use
- Limited cavitation‑free operating range compared with larger, higher‑power units
Typical Vessels:
Handymax bulk carrierSmall product tanker (up to ~30 000 DWT)Offshore supply vesselFerry or passenger liner of up to 5 000 GTContainer feeder ship
Decision Guide: Choose if you need a reliable, space‑efficient stern thruster for vessels up to ~30 000 DWT with modest maneuvering requirements and limited power budget. Avoid if the vessel demands higher thrust (>12 kN), operates frequently in high wind/sea states, or requires minimal hull resistance when the thruster is idle.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NIG-TT-100 bow
unverified
· 100.0 kW
· tunnel thruster
Power (kW)
100
Thrust (kN)
12.0
Diameter (mm)
580
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (≈12 kN at 100 kW) for its size
- Compact 580 mm tunnel fits narrow hull sections and bow spaces
- Niigata’s proven bearing and impeller design gives low vibration and noise
- Standard ABS/DNV type‑approval simplifies class approval processes
- Optional integrated control unit compatible with most ship bridge systems
Weaknesses
- Designed for vessels up to roughly 5 000 GT; may be under‑powered for larger ships
- Tunnel lining requires periodic inspection and cleaning to avoid fouling
- Spare‑part lead times can be longer outside the Asian market
- Single‑unit layout provides no redundancy if a failure occurs
- Compared with newer azimuth units, overall maneuvering flexibility is lower
Typical Vessels:
Offshore supply vesselFerryMedium‑size container ship (≤3 000 TEU)Cruise ship (mid‑range)Small to mid‑size bulk carrier
Certifications:
ABS Type ApprovalDNV GL Classification
Decision Guide: Choose if you need high bow thrust in a limited hull space on vessels up to about 5 000 GT and value proven reliability with class approvals. Avoid if the vessel requires redundant or 360° thrust capability, operates at very low speeds where azimuth thrusters are more efficient, or if rapid spare‑part availability is critical.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
NIG-TT-100 stern
unverified
· 100.0 kW
· tunnel thruster
Power (kW)
100
Thrust (kN)
12.0
Diameter (mm)
580
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (12 kN @ 100 kW) gives efficient manoeuvring capability.
- Compact 580 mm tunnel diameter fits a wide range of hull forms without excessive structural intrusion.
- Stern placement improves aft steering control, especially useful for DP and tight berthing operations.
- Niigata Marine’s reputation for robust construction and long‑life bearings reduces downtime.
- Standard 100 kW rating matches typical auxiliary power units on vessels up to ~30 000 DWT.
Weaknesses
- Maximum thrust of 12 kN may be insufficient for very large tankers or cruise ships requiring higher bollard pull.
- Tunnel geometry can generate cavitation noise if not optimally aligned with hull flow.
- Installation at the stern may limit access for routine inspection and maintenance compared with bow units.
- Power demand (100 kW) requires a dedicated generator or sufficient auxiliary capacity on smaller vessels.
Typical Vessels:
Handymax bulk carrierProduct tankerContainer feederOffshore supply vesselCruise ship tender
Decision Guide: Choose the NIG‑TT‑100 when a vessel needs reliable moderate thrust for port manoeuvring or DP assistance and has limited hull space for a larger tunnel unit. Avoid it on very large ships, high‑speed craft, or applications demanding >15 kN thrust or ultra‑low acoustic signatures.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NIG-TT-150 bow
unverified
· 150.0 kW
· tunnel thruster
Power (kW)
150
Thrust (kN)
18.0
Diameter (mm)
620
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (18 kN at 150 kW) for its size
- Compact 620 mm tunnel fits vessels with limited hull space
- Proven Japanese engineering with long service life and low vibration
- Straightforward installation and maintenance via accessible bearing housings
- Integrated control electronics compatible with most ship‑bridge systems
Weaknesses
- Limited to bow installations; not sized for high‑thrust stern applications
- Hull penetration required, increasing structural work during retrofit
- Power consumption may be high for vessels that could use azimuth pods for the same thrust
- Spare‑parts supply primarily through Asian distributors, which can affect lead times in remote regions
Typical Vessels:
Handymax bulk carrierFeeder container shipSmall product tanker (up to ~30 000 DWT)Offshore supply vesselCruise‑ship tender or similar medium‑size craft
Certifications:
IMO Type Approval (D-2)
Decision Guide: Choose if you need a reliable mid‑size bow thruster with up to 18 kN thrust, have limited hull space, and prefer proven Japanese build quality. Avoid if the vessel requires higher thrust (>25 kN), prefers an azimuth or pump‑jet solution, or operates in regions where rapid spare‑part support is critical.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NIG-TT-150 stern
unverified
· 150.0 kW
· tunnel thruster
Power (kW)
150
Thrust (kN)
18.0
Diameter (mm)
620
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (18 kN from 150 kW) for efficient manoeuvring
- Robust Niigata Marine construction with corrosion‑resistant alloys
- Compact duct size (620 mm) fits medium‑sized hull openings
- Low maintenance due to oil‑free, sealed rotor design
- Proven performance on DP‑class vessels
Weaknesses
- Requires a relatively large hull penetration; not suitable for very small ships
- Installation can be complex in existing vessels because of duct alignment
- Noise and vibration levels are higher than some azimuth thrusters at full power
- Limited thrust increase beyond 18 kN without upgrading to larger models
Typical Vessels:
TankersContainer shipsBulk carriersOffshore supply vesselsCruise ships
Decision Guide: Choose if you need reliable, high‑thrust stern manoeuvring on medium‑to‑large vessels and can accommodate a 620 mm tunnel duct. Avoid if vessel size or hull layout cannot support the required opening, or if ultra‑low noise is a primary requirement.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NIG-TT-200 bow
unverified
· 200.0 kW
· tunnel thruster
Power (kW)
200
Thrust (kN)
24.0
Diameter (mm)
660
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (24 kN from 200 kW) for effective low‑speed manoeuvring
- Relatively compact tunnel diameter (660 mm) fits into limited bow spaces
- Robust Niigata design with corrosion‑resistant alloys and sealed bearings
- Low vibration and acoustic signature compared with external propeller units
- Simple maintenance access via removable hull cover
Weaknesses
- Tunnel geometry limits efficiency at higher vessel speeds versus azimuth pods
- Requires hull penetration and structural reinforcement during installation
- Thrust direction is limited to yaw; no forward/reverse thrust component
- Potential for cavitation if not matched precisely to vessel hydrodynamics
- Spare‑part availability may be regionally variable
Typical Vessels:
Handymax Bulk CarrierContainer FeederOffshore Supply VesselCruise Ship TenderSmall Product Tanker
Certifications:
IMO Type Approval
Decision Guide: Choose if the vessel needs strong bow‑side manoeuvring in confined ports and has limited hull space for a thruster tunnel. Avoid if the ship relies on high‑speed azimuth propulsion or requires forward thrust capability beyond yaw control.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NIG-TT-200 stern
unverified
· 200.0 kW
· tunnel thruster
Power (kW)
200
Thrust (kN)
24.0
Diameter (mm)
660
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (≈24 kN @ 200 kW) for its size
- Compact 660 mm duct fits in vessels with limited hull space
- Robust Niigata bearing and seal design reduces maintenance intervals
- Relatively low acoustic signature compared with azimuth units
Weaknesses
- Fixed‑direction thrust; cannot provide full 360° vectoring like an azimuth thruster
- Cavitation risk at high propeller speeds in shallow water
- Power consumption higher than some newer electric pod‑type thrusters for equivalent maneuverability
- Installation requires hull penetration and duct reinforcement
Typical Vessels:
Container shipBulk carrierProduct tankerOffshore supply vesselCruise liner (mid‑size)
Decision Guide: Choose if: you need a reliable, high‑thrust stern thruster on a vessel with limited hull space and prefer proven mechanical simplicity. Avoid if: you require full azimuth thrust for dynamic positioning or want the lowest possible power draw for equivalent maneuverability.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NIG-TT-250 bow
unverified
· 250.0 kW
· tunnel thruster
Power (kW)
250
Thrust (kN)
30.0
Diameter (mm)
700
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (30 kN) relative to its 250 kW rating
- Compact 700 mm tunnel diameter fits into restricted hull spaces
- Integrated control electronics compatible with most bridge systems
- Proven reliability from Niigata Marine’s long‑standing product line
- Low vibration and noise levels compared with older screw‑type thrusters
Weaknesses
- Power consumption may be higher than newer, more efficient models offering similar thrust
- Limited thrust for very large vessels (>50 000 DWT) or high‑speed DP applications
- Tunnel installation can restrict access for routine maintenance
- Weight of the unit adds to overall vessel deadweight
- Standard model does not include built‑in redundancy for critical DP operations
Typical Vessels:
Handymax Bulk CarrierProduct Tanker (up to ~30 000 DWT)Medium‑size Container ShipCruise FerryOffshore Supply Vessel
Decision Guide: Choose if: you need a reliable 30 kN bow thruster for vessels up to ~40 000 DWT, have limited hull space and want a proven Niigata design with straightforward bridge integration. Avoid if: the vessel requires higher thrust levels, ultra‑low power consumption, or built‑in redundancy for high‑end dynamic positioning.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NIG-TT-250 stern
unverified
· 250.0 kW
· tunnel thruster
Power (kW)
250
Thrust (kN)
30.0
Diameter (mm)
700
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (30 kN at 250 kW) gives strong manoeuvring capability for its size
- Large 700 mm duct diameter promotes efficient water flow and reduced cavitation
- Compact stern installation frees up deck space compared with external azimuth units
- Niigata Marine’s reputation for robust construction and low maintenance intervals
- Suitable for integration with existing ship‑board control systems
Weaknesses
- Maximum thrust of 30 kN may be insufficient for large tankers or cruise ships requiring >40 kN
- Duct size (700 mm) can limit installation in vessels with tight hull geometry
- Requires dedicated power supply and possibly hydraulic/electric drive infrastructure
- No built‑in integrated control console; external controller needed
- Higher initial cost than basic low‑power thrusters (price not disclosed)
Typical Vessels:
Container feederGeneral cargoOffshore supply vesselProduct tanker (small to medium)Mid‑size cruise ship
Decision Guide: Choose if: you need a reliable 30 kN stern thrust for vessels up to ~10,000 gt, have sufficient hull space for a 700 mm tunnel, and value Niigata’s proven durability. Avoid if: the vessel requires higher thrust levels, has very tight aft compartments, or seeks an integrated azimuth solution.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NIG-TT-300 bow
unverified
· 300.0 kW
· Electric ducted tunnel thruster
Power (kW)
300
Thrust (kN)
36.0
Diameter (mm)
740
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (36 kN) relative to power consumption (300 kW)
- Compact tunnel layout saves deck space and reduces hull penetration
- Low acoustic signature and vibration compared with propeller‑type thrusters
- Integrated electronic control system compatible with DP and ship‑handling consoles
- Niigata Marine’s reputation for durability and long service intervals
Weaknesses
- Installation requires precise alignment and structural reinforcement of the hull opening
- Performance can drop in very shallow water where duct ventilation is limited
- Higher upfront cost than simple rudder‑assist or smaller thrusters
- Requires dedicated electrical supply and cooling infrastructure on board
- Potential for cavitation at high RPM if not matched to vessel’s operating profile
Typical Vessels:
Container shipCrude oil tankerProduct tankerLNG carrierCruise shipOffshore supply vessel
Decision Guide: Choose if the vessel needs strong bow‑side thrust for tight port manoeuvring, dynamic positioning support, or when deck space is limited and an electric drive is preferred. Avoid if only low‑power assistance is required, the hull cannot accommodate a tunnel duct, or budget constraints favour simpler steering aids.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NIG-TT-300 stern
unverified
· 300.0 kW
· tunnel thruster
Power (kW)
300
Thrust (kN)
36.0
Diameter (mm)
740
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust-to-power ratio (36 kN at 300 kW) provides strong lateral force for docking and DP operations.
- Compact 740 mm tunnel diameter fits into limited hull space, especially on vessels with narrow stern sections.
- Niigata Marine’s long‑standing reputation for reliability and low acoustic emissions.
- Straightforward installation and maintenance compared with more complex azimuth units.
- Robust construction suitable for continuous low‑speed operation in harsh marine environments.
Weaknesses
- Fixed transverse thrust direction; no 360° vectoring capability like azimuth pods.
- Higher power consumption than newer electric or hybrid thruster concepts for the same thrust level.
- Potential cavitation at high load or high RPM, requiring careful propeller design and operation limits.
- Internal bearings and seals need periodic dry‑dock inspection, adding maintenance downtime.
- Limited to stern placement; not suitable when bow thrust is also required.
Typical Vessels:
Product TankerHandymax Bulk CarrierOffshore Supply VesselCruise Ship (stern assistance)Container Feeder
Decision Guide: Choose if: the vessel requires strong transverse thrust for docking or dynamic positioning, has sufficient stern space for a 740 mm tunnel, and values proven reliability over full‑vectoring capability. Avoid if: you need 360° thrust control, are targeting ultra‑low power consumption, or prefer an azimuth pod solution.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NIG-TT-400 bow
unverified
· 400.0 kW
· tunnel thruster
Power (kW)
400
Thrust (kN)
48.0
Diameter (mm)
820
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust (48 kN) for its power rating gives excellent low‑speed manoeuvring capability.
- Relatively compact duct diameter (820 mm) fits into many hull designs without excessive structural modification.
- Niigata Marine’s reputation for robust, low‑maintenance marine propulsion equipment.
- Straightforward installation in a bow tunnel with standard mounting provisions.
- Direct thrust vectoring simplifies control integration with ship handling systems.
Weaknesses
- Tunnel geometry can induce hull vibration and noise if not properly isolated.
- Cavitation risk at high blade angles, requiring careful hydraulic design.
- Large power demand (400 kW) increases fuel consumption for vessels with limited auxiliary capacity.
- Fixed thrust direction limits flexibility compared with azimuth or pod thrusters.
- Requires sufficient bow space; may be unsuitable for very narrow hull forms.
Typical Vessels:
ContainerBulk CarrierTankerOffshore Supply VesselCruise Ship
Decision Guide: Choose if the vessel needs strong bow‑side thrust for port entry/exit, has adequate bow tunnel space for an 820 mm duct, and can accommodate a 400 kW power supply. Avoid if hull form is too narrow for the tunnel size, if lower fuel consumption or full 360° thrust vectoring is required, or if the vessel’s auxiliary system cannot support the power demand.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NIG-TT-400 stern
unverified
· 400.0 kW
· water‑cooled electric tunnel thruster
Power (kW)
400
Thrust (kN)
48.0
Diameter (mm)
820
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust (48 kN) relative to power rating, giving strong low‑speed maneuverability
- Compact 820 mm tunnel diameter allows installation on vessels with limited hull space
- Robust water‑cooled electric motor reduces overheating and extends service life
- Low vibration and noise compared with diesel‑driven thrusters
- Integrated control interface compatible with most ship bridge systems
Weaknesses
- Tunnel intrusion reduces usable cargo hold volume and may affect hull strength if not properly reinforced
- Higher power consumption (400 kW) increases onboard electrical load
- Maintenance of bearings, seals and water‑cooling circuit required at regular intervals
- Potential for cavitation when operating near maximum thrust in shallow water
- Not suitable for vessels with very deep drafts where tunnel depth would be excessive
Typical Vessels:
Container shipCrude oil tankerBulk carrierCruise linerOffshore supply vessel
Certifications:
DNVIMO Type Approval
Decision Guide: Choose if you need a high‑thrust, electrically driven stern thruster for large vessels where hull space is limited and precise low‑speed control is required. Avoid if the vessel has a deep draft that would make tunnel installation impractical or if you prefer azimuth/azipod solutions for 360° thrust.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NIG-TT-500 bow
unverified
· 500.0 kW
· electric tunnel thruster
Power (kW)
500
Thrust (kN)
60.0
Diameter (mm)
900
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (60 kN) suitable for vessels >150 m LOA
- Large tunnel diameter improves flow efficiency and reduces cavitation risk
- Compact bow installation frees deck space compared to external azimuth units
- Electric drive offers precise speed control and integration with DP systems
Weaknesses
- 500 kW power demand increases fuel consumption and requires robust electrical supply
- Tunnel geometry occupies significant hull volume, limiting use on smaller ships
- Maintenance of tunnel liner and bearings can be labour‑intensive
- Potential for higher noise/vibration levels at full thrust
Typical Vessels:
Container shipCrude oil tankerLNG carrierCruise linerOffshore support vessel
Decision Guide: Choose if the vessel needs strong bow thrust for tight port entries, dynamic positioning assistance, or high‑speed maneuvering and has sufficient hull space and power supply. Avoid if the ship is small, power‑limited, or if a simpler azimuth thruster would meet the manoeuvring requirements at lower cost.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NIG-TT-500 stern
unverified
· 500.0 kW
· tunnel thruster
Power (kW)
500
Thrust (kN)
60.0
Diameter (mm)
900
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (≈60 kN) relative to power rating (500 kW)
- Compact duct diameter (900 mm) eases installation in limited hull spaces
- Niigata’s proven water‑lubricated bearing system reduces routine maintenance
- Robust steel construction suited for harsh marine environments
- Integrated control electronics compatible with most ship bridge systems
Weaknesses
- Fixed‑direction thrust; cannot provide azimuthal thrust like a Z‑drive
- Potential for cavitation and duct wear at high RPM or prolonged use
- Installation requires hull penetration, adding structural complexity
- Higher drag when the thruster is not in operation compared with retractable units
- Power consumption higher than comparable electric azimuth thrusters for the same thrust
Typical Vessels:
TankerContainer shipBulk carrierGeneral cargo vesselOffshore supply vessel
Decision Guide: Choose if you need a reliable, high‑thrust stern thruster for vessels up to ~150 m LOA with limited hull space and prefer proven water‑lubricated bearings. Avoid if the ship requires full azimuth maneuverability, ultra‑low drag when idle, or operates at speeds where cavitation becomes critical.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NIG-TT-600 bow
unverified
· 600.0 kW
· tunnel thruster
Power (kW)
600
Thrust (kN)
72.0
Diameter (mm)
980
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust-to‑power ratio (72 kN at 600 kW) suitable for large ships requiring strong lateral force.
- Large tunnel diameter (980 mm) improves hydraulic efficiency and reduces cavitation risk at design load.
- Compact bow installation compared with external azimuth thrusters, preserving hull form.
- Proven Niigata Marine brand reputation for reliability in harsh marine environments.
Weaknesses
- Physical size of the tunnel limits fit on vessels with restricted bow space or shallow hull sections.
- Higher power rating leads to greater electrical/hydraulic demand and associated fuel consumption.
- Tunnel geometry can be prone to fouling and requires regular inspection of the duct lining.
- Installation and alignment are critical; retro‑fits on existing ships may involve significant structural work.
Typical Vessels:
Container shipBulk carrierCrude oil tankerLNG/LPG carrierOffshore supply vessel
Decision Guide: Choose if the vessel needs high bow thrust for precise docking, dynamic positioning or maneuvering in confined ports and has sufficient bow space to accommodate a ~1 m tunnel. Avoid if space is limited, power budget is tight, or the operator prefers azimuth thrusters for 360° thrust vectoring.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NIG-TT-600 stern
unverified
· 600.0 kW
· high‑power tunnel thruster
Power (kW)
600
Thrust (kN)
72.0
Diameter (mm)
980
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- 72 kN thrust at 600 kW gives excellent low‑speed manoeuvrability for large ships
- Large 980 mm duct diameter reduces cavitation and improves efficiency
- Niigata’s proven mechanical reliability and long service intervals
- Modular stern mounting simplifies installation on new builds
- Integrated control interface compatible with most ship bridge systems
Weaknesses
- High power rating leads to greater fuel consumption when used frequently
- Physical size may restrict fit in vessels with limited hull space or retro‑fit projects
- Initial capital cost is higher than lower‑power thrusters
- Larger bearings and seals require specialised maintenance tools
- Noise and vibration levels are higher than smaller, low‑speed units
Typical Vessels:
Crude oil tankerProduct tankerBulk carrier (≥30 kt)Container ship (≥8,000 TEU)Cruise liner
Decision Guide: Choose if: the vessel exceeds 20 000 GT and needs high thrust for port entry/exit or DP support, hull geometry can accommodate a ~1‑m duct, and budget allows a premium thruster. Avoid if: the ship is small, space‑constrained, or operating budgets restrict the higher power consumption.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
NIG-TT-750 bow
unverified
· 750.0 kW
· tunnel thruster
Power (kW)
750
Thrust (kN)
90.0
Diameter (mm)
1100
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust output (≈90 kN) for its power rating, improving low‑speed maneuverability
- Compact tunnel footprint allows installation on vessels with limited bow space
- Robust water‑lubricated design provides good reliability and low vibration
- Integrated cooling system enables continuous operation during dynamic positioning
- Proven track record on large commercial ships and offshore support vessels
Weaknesses
- Large tunnel diameter (1.1 m) may limit applicability on smaller hulls or retrofits
- Higher power consumption compared with some azimuth thruster solutions
- Maintenance access is confined to the tunnel interior, requiring dry‑dock periods
- Potential for cavitation at very high load conditions if not properly sized
- Weight and structural reinforcement requirements are significant
Typical Vessels:
Container shipCruise linerOffshore supply vesselLNG carrierRo‑Ro ferry
Certifications:
IMO Type ApprovalDNV
Decision Guide: Choose if you need a proven, high‑thrust bow thruster for large vessels where hull space allows a 1.1 m tunnel and continuous low‑speed maneuvering or DP support is required. Avoid if vessel size is limited, retrofitting constraints prevent a large tunnel, or an azimuth pod offers better all‑direction thrust with lower installation complexity.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
NIG-TT-750 stern
unverified
· 750.0 kW
· high‑efficiency tunnel thruster
Power (kW)
750
Thrust (kN)
90.0
Diameter (mm)
1100
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (~0.12 kN/kW) for its class
- Robust, corrosion‑resistant stainless steel construction
- Relatively compact installation footprint compared with azimuth units of similar power
- Low acoustic signature, suitable for passenger vessels
- Straightforward maintenance access via removable tunnel cover
Weaknesses
- Large tunnel diameter (1.1 m) may limit fit in narrow hull sections
- Fixed‑direction thrust; cannot provide vectoring like azimuth thrusters
- Potential cavitation at high load if inlet design not optimised for local flow conditions
- Higher power consumption than some newer ducted propeller designs for identical manoeuvring performance
Typical Vessels:
Container shipBulk carrierProduct tankerCruise linerOffshore supply vessel
Decision Guide: Choose if: you need a reliable, high‑thrust stern thruster for vessels with sufficient hull space and prefer a proven, low‑noise solution. Avoid if: the ship’s hull geometry cannot accommodate a 1.1 m tunnel or you require full 360° thrust vectoring for advanced dynamic positioning.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NIG-TT-800 bow
unverified
· 800.0 kW
· tunnel thruster
Power (kW)
800
Thrust (kN)
96.0
Diameter (mm)
1140
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (96 kN) suitable for maneuvering very large ships in confined ports
- Compact 1.14 m tunnel diameter allows installation in relatively narrow hull sections
- Niigata’s reputation for robust mechanical design and long service intervals
- Integrated control electronics compatible with most ship‑handling systems
Weaknesses
- Large power rating (800 kW) leads to high electrical/hydraulic demand and operating cost
- Requires significant hull penetration and structural reinforcement during installation
- Noise and vibration levels can be higher than smaller thrusters, may need additional mitigation
- Limited availability of spare parts in remote regions compared with more common Western brands
Typical Vessels:
Container shipCrude oil tankerLNG carrierCruise linerOffshore supply vessel
Decision Guide: Choose if the vessel needs a high‑power bow thruster for port entry, dynamic positioning or emergency maneuvering and has sufficient hull space for a 1.14 m tunnel. Avoid if the ship is small to medium size, power budget is limited, or installation complexity outweighs the thrust benefit.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NIG-TT-800 stern
unverified
· 800.0 kW
· tunnel thruster
Power (kW)
800
Thrust (kN)
96.0
Diameter (mm)
1140
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust-to-power ratio (≈96 kN at 800 kW) suitable for fast‑turning of large ships
- Compact tunnel design fits within limited hull space while delivering effective lateral force
- Robust Niigata Marine construction with proven reliability in harsh sea conditions
- Low acoustic signature compared with azimuth thrusters, beneficial for noise‑sensitive operations
Weaknesses
- Fixed direction; cannot rotate like a bow‑thruster or azimuth pod, limiting flexibility in tight berths
- Installation requires a sizable hull opening and internal ductwork, increasing retrofit cost
- Maintenance access can be difficult because the unit is located deep within the stern tunnel
- Power demand (800 kW) may require dedicated generator capacity on smaller vessels
Typical Vessels:
Crude oil tankerProduct tankerContainer shipBulk carrierCruise shipOffshore supply vessel
Decision Guide: Choose if you need a high‑thrust, space‑efficient stern thruster for vessels >30 000 gt that already have sufficient generator capacity and can accommodate a tunnel duct. Avoid if the ship requires 360° thrust vectoring, has severe weight or space constraints in the stern, or operates on limited power budgets.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NIG-TT-1000 bow
unverified
· 1000.0 kW
· tunnel thruster
Power (kW)
1000
Thrust (kN)
120.0
Diameter (mm)
1300
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (120 kN) relative to power rating, enabling rapid sideways movement.
- Compact tunnel diameter (1300 mm) fits within typical bow sections of large ships without excessive hull penetration.
- Robust Niigata design known for long service life and low maintenance intervals.
- Integrated control electronics compatible with most DP and ship‑handling systems.
Weaknesses
- Requires significant internal space in the bow, limiting installation on smaller vessels.
- Higher power consumption (1 MW) may increase fuel use during frequent maneuvering.
- Large duct can reduce hull strength locally; reinforcement may be needed.
- Potential for cavitation at high RPM if not matched with proper propeller design.
Typical Vessels:
Container shipCrude oil tankerLNG carrierCruise linerOffshore support vessel
Decision Guide: Choose if the vessel needs strong lateral thrust for port entry/exit, dynamic positioning or tight‑berth maneuvers and has sufficient bow volume for a 1.3 m tunnel. Avoid on small to medium vessels where space is limited or when power budget is constrained.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NIG-TT-1000 stern
unverified
· 1000.0 kW
· Tunnel thruster
Power (kW)
1000
Thrust (kN)
120.0
Diameter (mm)
1300
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (120 kN) suitable for large vessels
- Robust, proven tunnel design with good cavitation resistance
- Compact installation compared to azimuth units of similar power
- Straightforward integration into new builds with adequate hull space
Weaknesses
- Large tunnel diameter (1.3 m) consumes significant stern volume
- High electrical power demand (≈1000 kW)
- Fixed thrust direction; no 360° steering capability
- Potential for increased noise and vibration at full power
Typical Vessels:
Container shipBulk carrierTankerCruise linerRo‑Ro vessel
Decision Guide: Choose if the vessel requires strong low‑speed maneuverability and has sufficient stern space for a 1.3 m tunnel; ideal for new builds where power and thrust are priorities. Avoid if hull space is limited, lower thrust is acceptable, or a steerable (azimuth) thruster is preferred.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
NIG-TT-1200 bow
unverified
· 1200.0 kW
· high-power tunnel thruster
Power (kW)
1200
Thrust (kN)
144.0
Diameter (mm)
1460
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust-to-power ratio (144 kN @ 1200 kW)
- Large 1460 mm duct diameter reduces cavitation and improves efficiency
- Robust Niigata construction with low maintenance intervals
- Integrated cooling system suitable for continuous operation in hot climates
- Fits standard bow tunnel installations up to ~1.5 m width
Weaknesses
- High electrical power demand may require generator or distribution upgrades
- Physical size limits installation on smaller vessels or tight retrofits
- Tunnel geometry can lose efficiency in very shallow water due to suction effects
- Higher initial capital cost compared with lower‑power alternatives
- Requires regular inspection of duct seals to prevent leakage
Typical Vessels:
Cruise ShipContainer VesselLNG CarrierRo-Ro FerryOffshore Support Vessel
Decision Guide: Choose if: you need ≥140 kN thrust for precise low‑speed maneuvering on large vessels and have sufficient electrical capacity; the bow tunnel can accommodate a 1.46 m duct. Avoid if: the ship is small, power supply limited, or operations are primarily in very shallow water where azimuth thrusters may be more effective.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
NIG-TT-1200 stern
unverified
· 1200.0 kW
· Tunnel thruster
Power (kW)
1200
Thrust (kN)
144.0
Diameter (mm)
1460
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (144 kN) relative to power rating (1 200 kW)
- Large 1.46 m duct diameter provides efficient water flow and reduced cavitation
- Robust, low‑maintenance steel construction suitable for harsh marine environments
- Compact stern installation frees deck space compared with azimuth units
- Integrated cooling system allows continuous operation during DP maneuvers
Weaknesses
- Significant hull penetration required; structural reinforcement adds cost and weight
- Fixed thrust direction limits maneuverability versus rotating (azimuth) thrusters
- Higher power consumption than smaller bow thrusters for comparable vessel sizes
- Access for inspection/maintenance can be constrained in tight stern spaces
- Noise and vibration levels are higher than some low‑speed propeller designs
Typical Vessels:
Large container ships (8 000+ TEU)Cruise linersVLCCs / LR2 tankersLNG carriersOffshore supply and anchor handling tug supply vessels
Certifications:
IMO D‑2 Type Approval
Decision Guide: Choose if the vessel needs strong lateral thrust for docking, undocking or DP assistance and space constraints preclude a full azimuth unit. It is especially attractive on ships where a stern thruster can complement existing bow thrusters to balance forces. Avoid if 360° thrust vectoring is required, if hull modifications are prohibitive, or when operating in extreme wind/current conditions that exceed the fixed‑direction capability of a tunnel thruster.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NIG-TT-1500 bow
unverified
· 1500.0 kW
· tunnel thruster
Power (kW)
1500
Thrust (kN)
180.0
Diameter (mm)
1700
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (180 kN) suitable for large ships
- Robust Niigata Marine construction with proven reliability
- Large 1700 mm tunnel diameter provides high flow capacity and efficient thrust generation
- Integrated control interface compatible with common ship bridge systems
Weaknesses
- Requires a relatively deep hull tunnel (1.7 m) limiting installation on vessels with shallow drafts or restricted hull space
- High power rating (1500 kW) leads to greater electrical load and operating cost
- Initial capital cost is higher than smaller‑capacity thrusters
Typical Vessels:
Very Large Crude Carrier (VLCC)Ultra Large Container Vessel (ULCV)Bulk carrier (>150 kt)Cruise shipOffshore supply vessel
Decision Guide: Choose if the vessel requires a high‑power bow thruster for precise port manoeuvring, has sufficient hull space for a 1.7 m tunnel, and values Niigata’s reputation for durability. Avoid if the ship is smaller, has limited hull depth, or budget constraints make lower‑rated thrusters more appropriate.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
NIG-TT-1500 stern
unverified
· 1500.0 kW
· tunnel thruster
Power (kW)
1500
Thrust (kN)
180.0
Diameter (mm)
1700
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (180 kN) for a 1500 kW unit, giving excellent maneuverability on large vessels
- Robust stainless‑steel tunnel and propeller design reduces wear and extends service intervals
- Integrated control electronics compatible with most ship bridge systems
- Low vibration and noise levels compared with external azimuth thrusters of similar power
- Proven track record in Asian bulk carriers and tankers
Weaknesses
- Large tunnel diameter (1.7 m) requires significant hull cut‑out, limiting installation on smaller ships
- High electrical demand (1500 kW) may necessitate upgrades to ship power distribution
- Installation is complex; precise alignment of the tunnel and shaft is critical
- Cavitation can occur at very high propeller speeds if not properly matched to hull form
- Limited to stern applications – no bow version offered in this model line
Typical Vessels:
Container shipCrude oil tankerProduct tankerBulk carrierLNG/LPG carrierOffshore supply vessel
Decision Guide: Choose if: you need maximum thrust for a large vessel with sufficient hull space for a 1.7 m tunnel and have the electrical capacity to support 1500 kW; you require reliable low‑speed maneuvering in confined ports or DP operations. Avoid if: the ship is small, has limited stern space, or cannot accommodate the power and installation complexity.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NIG-TT-2000 bow
unverified
· 2000.0 kW
· tunnel thruster
Power (kW)
2000
Thrust (kN)
240.0
Diameter (mm)
2100
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (≈240 kN) relative to installed power, enabling rapid lateral movement.
- Compact tunnel design fits within standard bow sections of large ships without excessive hull penetration.
- Integrated water‑cooling system reduces overheating during prolonged DP operations.
- Low acoustic signature compared with azimuth thrusters, beneficial for passenger comfort and marine life.
- Modular construction simplifies on‑site installation and future maintenance.
Weaknesses
- Large tunnel diameter (2.1 m) limits applicability to vessels with sufficient bow space.
- High power demand (2 000 kW) increases overall ship electrical load and fuel consumption for diesel generators.
- Potential cavitation at full‑load conditions may require careful propeller design and monitoring.
- Installation requires precise alignment; retrofits on existing hulls can be costly and time‑consuming.
- Spare parts and specialized service support are less widespread outside major Asian shipyards.
Typical Vessels:
Container shipsCruise linersLNG carriersOffshore supply vesselsBulk carriers
Decision Guide: Choose if the vessel needs high bow‑side thrust for dynamic positioning, tight port manoeuvring, or emergency stopping and has sufficient bow volume to accommodate a 2.1 m tunnel. Avoid on smaller ships, vessels with restricted hull space, or projects where lower upfront cost and power consumption are higher priorities than maximum thrust.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NIG-TT-2000 stern
unverified
· 2000.0 kW
· tunnel thruster
Power (kW)
2000
Thrust (kN)
240.0
Diameter (mm)
2100
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust (240 kN) suitable for very large ships and tight docking maneuvers
- Robust tunnel design tolerates harsh sea conditions and debris ingress
- Relatively compact installation compared with azimuth pods, saving deck space
- Direct integration with ship’s power plant – 2 MW rating matches many main‑engine outputs
- Proven manufacturer reputation for reliability in commercial fleets
Weaknesses
- Fixed thrust direction; requires helm coordination or additional bow thrusters for full DP capability
- Tunnel geometry can cause increased hull resistance and potential cavitation at higher speeds
- Installation involves significant hull penetration, increasing dry‑dock time and cost
- Weight and size may limit retrofit options on smaller vessels
Typical Vessels:
Container ships (>10 000 TEU)Cruise linersLarge tankers (VLCC, ULCC)Offshore supply vesselsLNG carriers
Decision Guide: Choose if the vessel requires very high stern thrust for docking, undocking or low‑speed maneuvering and has sufficient hull space for a tunnel installation. Avoid if you need fully rotatable thrust (azimuth) for dynamic positioning, have limited hull penetration allowance, or operate at speeds where tunnel cavitation becomes critical.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
NIG-TT-2500 bow
unverified
· 2500.0 kW
· tunnel thruster
Power (kW)
2500
Thrust (kN)
300.0
Diameter (mm)
2500
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust‑to‑power ratio (≈300 kN from 2 500 kW)
- Robust steel tunnel housing suitable for heavy‑duty service
- Integrated control system with feedback for precise DP operation
- Low maintenance design – sealed motor and bearings protected inside the duct
- IMO Type Approval (D‑2) ensures compliance with international safety standards
Weaknesses
- Large 2.5 m diameter tunnel requires significant hull penetration and structural reinforcement
- High electrical power demand may necessitate upgrades to ship’s power distribution
- Noise and vibration can be noticeable at full load, requiring acoustic mitigation in passenger vessels
- Installation space is limited on smaller or narrow‑beam ships
- Less flexible than azimuth or podded thrusters for lateral thrust vectoring
Typical Vessels:
VLCC/Aframax TankerLarge Container Ship (≥8,000 TEU)Cruise ShipOffshore Supply VesselLNG Carrier
Certifications:
IMO Type Approval (D‑2)
Decision Guide: Choose if the vessel requires very high bow thrust for safe docking, undocking or DP support and can accommodate a 2.5 m tunnel with adequate structural reinforcement; the proven reliability and IMO D‑2 approval add confidence for class societies. Avoid if hull space is constrained, budget limits power system upgrades, or if a more versatile azimuth thruster is preferred for lateral thrust vectoring.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NIG-TT-2500 stern
unverified
· 2500.0 kW
· high-power tunnel thruster
Power (kW)
2500
Thrust (kN)
300.0
Diameter (mm)
2500
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust output (≈300 kN) for its power rating, enabling strong lateral force at the stern
- Compact tunnel design fits within limited hull space while providing robust performance
- Robust steel construction and proven Niigata bearing system give long service intervals
- Integrated control electronics compatible with most DP‑2/DP‑3 systems
- Low cavitation risk due to optimized impeller geometry
Weaknesses
- High electrical power demand (≈2.5 MW) requires substantial onboard generation capacity
- Large hull penetration and tunnel duct may complicate retrofits on existing ships
- Spare‑part supply is primarily through Niigata’s Asian network, which can increase lead times for some regions
- Installation weight adds to overall vessel deadweight (exact figure not disclosed)
- Noise and vibration levels are higher than smaller thrusters; mitigation may be needed
Typical Vessels:
Container shipCrude oil tankerProduct tankerCruise linerOffshore supply vesselLNG carrier
Decision Guide: Choose if: the vessel requires high stern thrust for DP‑2/DP‑3 operations, has sufficient power generation capacity, and can accommodate a tunnel duct in the hull. Avoid if: budget constraints limit the purchase of a 2.5 MW unit, retrofitting space is extremely limited, or local support for Niigata spares is unavailable.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
NIG-TT-3000 bow
unverified
· 3000.0 kW
· tunnel thruster
Power (kW)
3000
Thrust (kN)
360.0
Diameter (mm)
2900
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (360 kN) suitable for vessels >150 000 dwt
- Compact installation footprint compared with azimuth pods of similar power
- Integrated water‑lubricated bearing system reduces vibration and noise
- Robust steel tunnel housing offers good protection against hull impacts
Weaknesses
- Large tunnel diameter (2.9 m) may limit placement on vessels with narrow bow sections
- High electrical demand (≈3 MW) requires substantial shore‑side power infrastructure
- Maintenance access to the impeller and bearings can be restricted once installed
- Potential for cavitation at maximum thrust if water flow is not optimised
Typical Vessels:
Ultra‑large Container Ship (ULCS)Very Large Crude Carrier (VLCC)LNG CarrierCruise ShipOffshore Supply Vessel
Decision Guide: Choose if: you need maximum bow thrust for a very large vessel operating in tight ports or requiring dynamic positioning support, and the hull can accommodate a 2.9 m tunnel. Avoid if: hull geometry restricts tunnel size, power supply is limited, or lower‑cost azimuth thrusters meet the maneuverability requirement.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
NIG-TT-3000 stern
unverified
· 3000.0 kW
· tunnel thruster
Power (kW)
3000
Thrust (kN)
360.0
Diameter (mm)
2900
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (≈360 kN) suitable for vessels >150 000 dwt
- Robust, marine‑grade stainless steel construction with proven service life
- Integrated control and monitoring system compatible with most bridge consoles
- Low maintenance design – brushless motor and sealed tunnel reduces wear
- Proven performance on a range of large commercial ships
Weaknesses
- Large diameter requires significant hull penetration and structural reinforcement
- High power demand (≈3 MW) increases fuel consumption when used frequently
- Initial procurement cost is higher than smaller thrusters or azimuth pods
- Spare parts logistics can be slower in remote ports without Niigata dealer presence
- Installation downtime may be longer due to extensive retro‑fit work
Typical Vessels:
Very Large Crude Carriers (VLCC)Ultra‑Large Container Vessels (ULCV)Bulk carriers >150 000 dwtCruise ships and mega‑yachtsOffshore support vessels with DP requirements
Decision Guide: Choose if the vessel requires very high thrust for safe docking, low‑speed manoeuvring or dynamic positioning on ships larger than 150 000 dwt and hull space can accommodate a 2.9 m tunnel. Avoid if the ship has limited stern space, lower thrust needs, or budget constraints that favour smaller thrusters or azimuth pods.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NIG-TT-3500 bow
unverified
· 3500.0 kW
· tunnel thruster
Power (kW)
3500
Thrust (kN)
420.0
Diameter (mm)
3300
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (≈420 kN) suitable for large vessels and DP operations
- Compact tunnel layout saves deck space compared with external azimuth units
- Robust Niigata design known for long service life and corrosion‑resistant materials
- Integrated control electronics compatible with most bridge automation systems
Weaknesses
- High power demand (≈3.5 MW) increases fuel consumption and requires strong shipboard electrical supply
- Large tunnel diameter (3.3 m) demands significant hull penetration and structural reinforcement
- Installation and maintenance are complex, requiring specialised dockyard facilities
- Spare‑part availability may be limited in regions without a Niigata service network
Typical Vessels:
Ultra‑large container shipsVery large crude carriers (VLCC) and product tankersCruise linersLNG carriersOffshore supply vessels with dynamic positioning
Decision Guide: Choose the NIG-TT-3500 when a vessel needs maximum low‑speed thrust for tight port entry, dynamic positioning or emergency maneuvering and can accommodate the required hull modifications and power supply. Avoid it on smaller ships, where lower‑power thrusters are more economical, or when installation time and cost are critical constraints.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NIG-TT-3500 stern
unverified
· 3500.0 kW
· high‑power tunnel thruster
Power (kW)
3500
Thrust (kN)
420.0
Diameter (mm)
3300
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (420 kN) suitable for DP and tight berthing operations on large ships
- Large 3300 mm duct diameter provides efficient water flow and reduced cavitation
- Robust water‑lubricated bearing system lowers maintenance intervals
- Integrated control electronics compatible with common ship automation systems
- Proven Niigata Marine design reputation for reliability in harsh marine environments
Weaknesses
- Large physical footprint may limit installation on vessels with restricted hull space
- High electrical power demand (≈3500 kW) requires substantial onboard generation capacity
- Installation and commissioning costs are significant compared with smaller thrusters
- Requires dedicated cooling and ventilation arrangements in the stern tunnel
- Spare‑part logistics can be longer for ships operating far from Asian supply hubs
Typical Vessels:
VLCC / ULCCLNG carrierCruise shipLarge container vessel (>10,000 TEU)Offshore support vessel with DP2 capability
Decision Guide: Choose if the vessel needs very high stern thrust for dynamic positioning, tight port maneuvering or emergency backup on a large hull with ample power generation. Avoid if the ship’s size, power plant or available tunnel space cannot accommodate a 3.3 m duct and the associated electrical load.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NIG-TT-4000 bow
unverified
· 4000.0 kW
· high‑power tunnel thruster
Power (kW)
4000
Thrust (kN)
480.0
Diameter (mm)
3700
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (480 kN) enables precise manoeuvring of large vessels in confined ports
- Large 3.7 m duct reduces cavitation and improves efficiency at high power levels
- Robust Niigata Marine construction with corrosion‑resistant alloys for long service life
- Integrated control electronics compatible with most DP and ship‑handling systems
- Low acoustic signature compared with conventional azimuth thrusters of similar size
Weaknesses
- Large physical footprint occupies significant hull space, limiting installation options
- High electrical demand (≈4 MW) requires substantial onboard power generation capacity
- Complex installation and alignment procedures increase dock‑time during retrofits
- Maintenance of oversized bearings and seals can be costly and require specialised tools
- Spare parts may have longer lead times in regions without a Niigata Marine service centre
Typical Vessels:
LNG carrierCruise shipVery large crude carrier (VLCC)Ultra‑large container vessel (ULCV)Offshore supply / support vessel
Decision Guide: Choose if: the vessel requires >400 kN bow thrust for safe port entry, high wind/sea conditions, or DP assistance on a large hull. Avoid if: the ship’s power plant cannot accommodate ~4 MW of thruster load, space constraints prevent a 3.7 m duct, or a lower‑cost, lower‑power thruster meets manoeuvring needs.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NIG-TT-4000 stern
unverified
· 4000.0 kW
· high‑power tunnel thruster
Power (kW)
4000
Thrust (kN)
480.0
Diameter (mm)
3700
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust output (≈480 kN) suitable for the largest tankers and cruise ships
- Compact stern installation compared with azimuth pods of similar power
- Robust Niigata Marine design known for long service intervals
Weaknesses
- High electrical demand (4 MW) requiring substantial shore‑side power infrastructure
- Large duct diameter (3.7 m) can limit hull space and increase structural integration work
- Potential cavitation at maximum thrust if not matched with proper propeller design
Typical Vessels:
VLCC/TankerLNG CarrierCruise ShipOffshore Supply VesselFPSO
Decision Guide: Choose if the vessel requires very high thrust for low‑speed manoeuvring, dynamic positioning or tight berth assistance and can accommodate a 3.7 m tunnel diameter and 4 MW power supply. Avoid if hull space is limited, power generation capacity is constrained, or a lower‑cost azimuth thruster meets the required thrust.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NIG-TT-4500 bow
unverified
· 4500.0 kW
· Tunnel bow thruster
Power (kW)
4500
Thrust (kN)
540.0
Diameter (mm)
4100
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (540 kN) relative to power, enabling rapid lateral movement of large vessels
- Large 4.1 m duct diameter reduces cavitation and improves efficiency at high loads
- Robust stainless‑steel housing designed for harsh marine environments and easy access for maintenance
- Integrated variable‑frequency drive (VFD) allows fine thrust control and energy optimisation
- Proven track record on ultra‑large commercial ships, supporting dynamic positioning and tight‑port operations
Weaknesses
- High installed power (4.5 MW) demands substantial electrical supply and cooling capacity
- Large duct size requires significant bow space and hull reinforcement, limiting retrofit options
- Higher capital cost compared with lower‑power thrusters of similar make
- Increased fuel consumption when operated at full thrust for extended periods
- Complex installation may extend shipyard schedule
Typical Vessels:
Ultra‑large container shipsCrude oil and product tankers (>80,000 dwt)LNG carriersCruise linersOffshore supply vessels (OSVs) with DP capabilityHeavy‑lift and ro-ro vessels
Decision Guide: Choose if the vessel requires high lateral thrust for port entry/exit, dynamic positioning or emergency maneuvering on ships >80 000 dwt where hull space permits a large tunnel duct. Avoid if the ship’s power plant cannot support an additional 4.5 MW load, budget constraints are tight, or the bow geometry does not allow a 4.1 m diameter installation.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
NIG-TT-4500 stern
unverified
· 4500.0 kW
· Tunnel Thruster
Power (kW)
4500
Thrust (kN)
540.0
Diameter (mm)
4100
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (540 kN) suitable for large vessels and tight berthing situations
- Large 4100 mm duct provides efficient water flow with reduced cavitation
- Integrated Niigata control system allows fine‑tuned thrust vectoring
- Robust marine‑grade construction rated for continuous 4500 kW operation
- Proven track record of reliability on high‑power applications
Weaknesses
- Large physical footprint limits installation to vessels with ample stern space
- High power demand (4.5 MW) increases fuel consumption and electrical load
- Installation and alignment are more complex than smaller thrusters
- Maintenance intervals can be longer due to size of rotating components
- Potential for higher acoustic signature in confined ports
Typical Vessels:
Container ShipCrude Oil TankerLNG CarrierCruise ShipOffshore Supply Vessel
Certifications:
IMO Type Approval (D‑2)DNV GL Classification
Decision Guide: Choose if: you need strong stern thrust for vessels >150 m LOA, frequent port turns, or dynamic positioning where high maneuverability is critical. Avoid if: vessel size or stern geometry cannot accommodate a 4.1 m duct, power supply is limited, or low‑cost/low‑power thrusters are sufficient.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NIG-TT-5000 bow
unverified
· 5000.0 kW
· tunnel bow thruster
Power (kW)
5000
Thrust (kN)
600.0
Diameter (mm)
4500
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (≈600 kN) suitable for mega‑size ships and offshore support vessels
- Robust tunnel design provides good protection against fouling and impact damage
- Integrated cooling system allows continuous operation at full power
- Proven manufacturer with a long service record in the marine market
Weaknesses
- High electrical demand (≈5 MW) may require significant generator capacity
- Large hull penetration (4.5 m diameter) limits retrofit options on smaller ships
- Potential for cavitation at very high blade speeds, requiring careful operation
- Spare‑parts inventory and specialised installation expertise can be limited in remote ports
Typical Vessels:
Container ship (>10,000 TEU)Cruise linerLNG carrierOffshore supply vesselHeavy lift / RoRo vessel
Certifications:
IMO Type ApprovalDNV Class approval
Decision Guide: Choose if the vessel requires exceptional low‑speed thrust for port entry/exit, dynamic positioning or offshore operations and can accommodate the power and hull‑size requirements. Avoid if the ship has limited generator capacity, tight hull space, or if a lower‑cost, smaller thruster meets maneuverability needs.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
NIG-TT-5000 stern
unverified
· 5000.0 kW
· tunnel thruster
Power (kW)
5000
Thrust (kN)
600.0
Diameter (mm)
4500
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (≈600 kN) from a 5 MW motor enables rapid berthing and unberthing of large ships.
- Large 4.5 m tunnel diameter provides high water flow with reduced cavitation risk.
- Robust, low‑maintenance construction with sealed stator cooling and easy access hatch for service.
- Integrated variable frequency drive (VFD) allows fine thrust control for dynamic positioning.
- Proven track record on deep‑draft vessels; compatible with major classification societies.
Weaknesses
- Large tunnel footprint consumes significant hull space, limiting use on ships with restricted beam or draft.
- Installation requires substantial hull penetration and reinforcement, increasing build cost.
- Less maneuverable than azimuthing pod thrusters for high‑precision DP operations.
- Higher power consumption compared to smaller thrusters; may impact fuel efficiency when used continuously.
Typical Vessels:
Very Large Crude Carrier (VLCC)Container ship (>10,000 TEU)Cruise linerLNG carrierBulk carrier (>200 kt)
Certifications:
DNV GL Type Approval
Decision Guide: Choose if you need a very high thrust rating for deep‑draft, large vessels where hull space permits a tunnel installation and low noise/maintenance are priorities. Avoid if the vessel operates in shallow water, requires azimuthing thrust for precise DP work, or has strict weight and space constraints.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
XEAMOS Marine
44
XM-TT-50 bow
unverified
· 50.0 kW
· tunnel thruster
Power (kW)
50
Thrust (kN)
6.0
Diameter (mm)
540
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Compact installation in the hull due to its tunnel design
- Relatively low power consumption (50 kW) for modest thrust requirements
- Water‑lubricated bearings reduce maintenance compared with oil‑filled units
- Suitable for vessels where space at the bow is limited
Weaknesses
- Maximum thrust of 6 kN may be insufficient for large tankers or high‑wind conditions
- Tunnel geometry can be prone to cavitation if operated near design limits
- Limited redundancy – a single unit provides all bow‑side thrust
- Performance highly dependent on proper hull integration and sealing
Typical Vessels:
Coastal bulk carrier (up to ~20,000 dwt)Feeder container shipOffshore supply vesselSmall passenger ferryWorkboat / tug‑assist craft
Decision Guide: Choose if the vessel requires a modest bow‑thruster for precise docking, operates in confined ports, and has limited available power. Avoid if the ship needs high thrust (>10 kN), operates in severe sea states, or demands redundant thruster systems.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
XM-TT-50 stern
unverified
· 50.0 kW
· tunnel thruster
Power (kW)
50
Thrust (kN)
6.0
Diameter (mm)
540
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Compact 540 mm tunnel fits in vessels with limited hull space
- 50 kW motor provides adequate thrust (6 kN) for small‑to‑medium sized ships
- Simple, proven tunnel design offers high reliability and low maintenance
- Integrated stern mounting enhances maneuverability during docking and berthing
- Direct hydraulic or electric drive options simplify installation
Weaknesses
- Maximum thrust (6 kN) may be insufficient for large vessels or heavy‑weather operations
- Hull penetration required for tunnel installation can increase corrosion risk if not sealed properly
- Potential cavitation and noise at high propeller speeds
- Power draw reduces available shaft power for propulsion in low‑power ships
- Limited thrust vectoring compared with azimuth thrusters
Typical Vessels:
Offshore supply vesselCoastal cargo shipFerrySmall container feederWorkboat / tug (light duty)
Decision Guide: Choose if: you need a cost‑effective, compact stern thruster for vessels up to ~3 000 gt that require moderate docking assistance and have limited hull space. Avoid if: the vessel demands high thrust (>10 kN), operates in extreme weather, or requires full azimuth maneuverability for DP2/DP3 operations.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
XM-TT-75 bow
unverified
· 75.0 kW
· tunnel thruster
Power (kW)
75
Thrust (kN)
9.0
Diameter (mm)
560
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (≈9 kN @ 75 kW) for its size
- Compact 560 mm tunnel diameter fits vessels with limited hull space
- Low acoustic signature – suitable for noise‑sensitive operations
- Standardised mounting and wiring simplify installation on new builds or retrofits
- Integrated control interface compatible with most ship bridge systems
Weaknesses
- Limited thrust for very large vessels (>150 m LOA) compared with higher‑power azimuth units
- Performance drops in deep water or high‑speed transit due to tunnel flow losses
- Requires regular bearing and seal inspection to avoid premature wear
- Fixed direction – cannot provide lateral thrust on the stern without a second unit
Typical Vessels:
Offshore supply vesselFerry (up to 150 m)Mid‑size container shipCruise ship (mid‑range)Coastal tanker
Decision Guide: Choose if: you need a reliable, compact bow thruster for vessels up to about 150 m LOA where space is limited and low noise is important. Avoid if: the vessel requires very high thrust levels (e.g., large tankers or ultra‑large container ships) or you prefer a steerable azimuth unit for both bow and stern manoeuvring.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
XM-TT-75 stern
unverified
· 75.0 kW
· Tunnel thruster
Power (kW)
75
Thrust (kN)
9.0
Diameter (mm)
560
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (≈0.12 kN/kW) for its size
- Compact 560 mm diameter fits vessels with limited hull space
- Integrated stern mounting reduces the number of hull penetrations
- XEAMOS Marine reputation for robust, low‑maintenance designs
Weaknesses
- Maximum thrust (9 kN) may be insufficient for large DP‑required ships
- Installation requires a sizable hull cut‑out and structural reinforcement
- Power demand (75 kW) can strain vessels with limited electrical generation capacity
- Potential for higher acoustic noise compared with larger, slower‑turning units
Typical Vessels:
Product tankerOffshore supply vesselCruise ship (mid‑size)Container feederBulk carrier up to ~30 000 DWT
Decision Guide: Choose if: you need a moderate‑power stern thruster for vessels with limited hull space and require reliable, low‑maintenance operation. Avoid if: the vessel demands higher thrust (>12 kN), has strict noise limits, or cannot accommodate the required hull cut‑out.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
XM-TT-100 bow
unverified
· 100.0 kW
· tunnel thruster
Power (kW)
100
Thrust (kN)
12.0
Diameter (mm)
580
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust-to-power ratio (12 kN @ 100 kW)
- Compact 580 mm tunnel diameter fits in medium‑size bow sections
- Direct‑drive motor reduces mechanical losses and maintenance
- Low acoustic signature compared with azimuth thrusters
- Integrated control interface compatible with common bridge systems
Weaknesses
- Limited to vessels where 12 kN thrust is sufficient (e.g., up to ~30,000 dwt)
- Fixed direction; cannot provide lateral thrust without turning the vessel
- Tunnel geometry may be prone to cavitation in high‑speed water flow
- Requires bow space for duct and motor installation, reducing cargo volume
- Maintenance access can be restricted on some hull forms
Typical Vessels:
General cargoContainer feederSmall tankerOffshore supply vessel
Decision Guide: Choose if you need a reliable, compact bow thruster delivering 12 kN thrust for vessels up to medium size and prefer lower cost and simpler installation than azimuth units. Avoid if your ship requires higher thrust, 360° thrust vectoring, or operates in high‑speed conditions where cavitation risk is critical.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
XM-TT-100 stern
unverified
· 100.0 kW
· tunnel thruster
Power (kW)
100
Thrust (kN)
12.0
Diameter (mm)
580
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (12 kN @ 100 kW)
- Compact 580 mm diameter fits tight hull spaces
- Optimised duct geometry reduces cavitation and noise
- Straightforward stern installation with standard mounting brackets
- Proven reliability in medium‑size commercial vessels
Weaknesses
- Maximum thrust may be insufficient for very large tankers or high‑speed DP applications
- Requires regular bearing and seal maintenance typical of tunnel units
- Limited to vessels where a stern thruster can be accommodated within hull geometry
- Potential for higher vibration at full load compared with larger‑diameter models
Typical Vessels:
Offshore supply vesselWorkboat / tug‑assist craftMedium‑size container ship (up to ~30 000 DWT)FerryCoastal bulk carrier
Decision Guide: Choose if: you need a reliable, compact stern thruster for vessels up to ~30 000 DWT that require good maneuverability in ports or during low‑speed operations. Avoid if: the vessel demands higher thrust (>15 kN) for heavy DP work, or if hull design cannot accommodate a 580 mm tunnel unit.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
XM-TT-150 bow
unverified
· 150.0 kW
Power (kW)
150
Thrust (kN)
18.0
Diameter (mm)
620
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (18 kN at 150 kW) for its size
- Compact 620 mm tunnel diameter fits into limited hull spaces
- Robust tunnel design provides good protection against debris and grounding
- Low draft installation suitable for vessels with shallow under‑keel clearance
- Straightforward integration with standard ship control systems
Weaknesses
- Maximum thrust may be insufficient for large tankers or high‑power DP requirements
- Tunnel geometry can generate higher acoustic noise compared with azimuth units
- Potential cavitation at high RPMs if not properly matched to hull form
- Installation requires precise alignment of the duct and propeller, increasing fit‑out time
- Limited thrust vectoring – only fixed 0° direction
Typical Vessels:
Handymax bulk carrierProduct tanker (up to ~30 000 DWT)Container feederOffshore supply vesselMid‑size cruise ship
Decision Guide: Choose if: you need a reliable, compact bow thruster delivering around 18 kN for vessels up to ~40 000 DWT with limited hull space and shallow draft. Avoid if: the vessel requires higher thrust (>25 kN), full‑360° vectoring, or ultra‑quiet operation where an azimuth pod would be preferable.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
XM-TT-150 stern
unverified
· 150.0 kW
· tunnel thruster
Power (kW)
150
Thrust (kN)
18.0
Diameter (mm)
620
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (18 kN from 150 kW)
- Large 620 mm duct diameter provides efficient water flow
- Stern mounting enhances push‑pull control for docking and DP assistance
- Compact footprint suitable for retrofits on existing hulls
- Sealed motor housing designed for low maintenance
Weaknesses
- Maximum thrust of 18 kN may be insufficient for very large vessels or extreme environmental conditions
- 150 kW power demand adds to the ship's electrical load
- Installation requires hull penetration and structural reinforcement
- No publicly documented certifications may limit class approval in some registries
- Tunnel design can suffer suction effects in shallow water
Typical Vessels:
Medium‑range tankerContainer feederBulk carrier (up to ~30,000 DWT)Offshore supply vesselCruise ship tender
Decision Guide: Choose if you need a reliable stern thruster delivering around 18 kN thrust for vessels up to medium deadweight and have space for a 620 mm tunnel. Avoid if higher thrust (>20 kN) or lower power consumption is required, or if class societies demand specific certifications that are not listed.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
XM-TT-200 bow
unverified
· 200.0 kW
· tunnel thruster
Power (kW)
200
Thrust (kN)
24.0
Diameter (mm)
660
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (24 kN at 200 kW) for its size
- Relatively small tunnel diameter (660 mm) eases hull integration on medium‑size vessels
- Robust, low‑maintenance electric motor design typical of XEAMOS units
- Good directional control for docking and low‑speed manoeuvring
Weaknesses
- Tunnel geometry can limit efficiency at very low ship speeds, increasing cavitation risk
- Installation requires precise hull cut‑out and sealing; retrofits are labor‑intensive
- Limited thrust compared with azimuth or pod thrusters of similar power for high‑performance DP applications
- Noise and vibration may be higher than ducted propeller alternatives in some installations
Typical Vessels:
Offshore supply vesselCruise ship (mid‑size)Container feederGeneral cargo / bulk carrier up to ~150 m LOALNG/LPG carriers with moderate maneuvering requirements
Decision Guide: Choose if you need a compact, high‑thrust bow thruster for vessels where hull space is limited and the primary requirement is docking or low‑speed manoeuvring. Avoid if the vessel requires maximum thrust efficiency at very low speeds, ultra‑low cavitation, or if an azimuth/azipod solution would better support dynamic positioning or high‑power maneuvering.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
XM-TT-200 stern
unverified
· 200.0 kW
· tunnel thruster
Power (kW)
200
Thrust (kN)
24.0
Diameter (mm)
660
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (24 kN) relative to its 200 kW power rating
- Relatively small tunnel diameter (660 mm) fits vessels with limited hull space
- Robust tunnel design provides good protection against debris and grounding impacts
- Integrated control electronics compatible with most ship‑board maneuvering systems
Weaknesses
- Power consumption is significant for vessels seeking ultra‑low fuel use during maneuvers
- Maximum thrust may be insufficient for very large tankers or high‑wind offshore operations
- Installation requires stern hull penetration and structural reinforcement, adding dock‑time
- Limited published data on noise/vibration performance
Typical Vessels:
Offshore supply vesselFerryContainer feederSmall to medium tankerBulk carrier (up to ~30 000 dwt)
Decision Guide: Choose if: you need a compact stern thruster delivering around 24 kN for precise docking, dynamic positioning assistance or emergency maneuvering on vessels up to medium size, and you have sufficient hull space for a 660 mm tunnel. Avoid if: the vessel requires higher thrust levels (>30 kN), ultra‑low power draw, or you cannot accommodate stern penetration work during construction/retrofit.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
XM-TT-250 bow
unverified
· 250.0 kW
· tunnel thruster
Power (kW)
250
Thrust (kN)
30.0
Diameter (mm)
700
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (30 kN) relative to power rating, improving docking control
- Compact 700 mm tunnel diameter fits into medium‑size hulls without excessive structural modification
- Robust electric motor with integrated controller simplifies installation and wiring
- Low vibration and noise compared with external propeller thrusters
Weaknesses
- Requires significant hull penetration, increasing initial fit‑out cost and potential for leaks if not properly sealed
- Power consumption at full thrust can be high, impacting ship’s auxiliary power budget
- Effectiveness diminishes in strong currents or heavy seas where bow thruster alone may be insufficient
- Maintenance of internal bearings and seals is mandatory to avoid premature wear
Typical Vessels:
ContainerGeneral CargoRo‑RoOffshore Supply VesselMedium‑size Bulk Carrier (up to ~15 000 DWT)
Decision Guide: Choose if: you need strong bow maneuverability for vessels up to roughly 15 000 DWT, have limited stern thruster space and can accommodate a 700 mm tunnel opening. Avoid if: the vessel exceeds 20 000 DWT, operates primarily in high‑current or open‑sea conditions where additional propulsion is required, or you prefer a shaft‑driven external thruster for easier retrofit.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
XM-TT-250 stern
unverified
· 250.0 kW
· tunnel thruster
Power (kW)
250
Thrust (kN)
30.0
Diameter (mm)
700
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (30 kN at 250 kW) suitable for medium‑size vessels
- Compact duct diameter (700 mm) eases installation in confined stern spaces
- Tunnel design provides good protection of the propeller against debris and grounding impacts
- Direct‑drive motor reduces mechanical complexity and maintenance intervals
Weaknesses
- Limited thrust compared with larger azimuth or pod thrusters for high‑power DP applications
- Fixed‑direction operation requires separate steering gear, adding system complexity
- Potential cavitation at higher RPMs due to relatively small duct size
- No publicly confirmed certification or class approval information
Typical Vessels:
Offshore supply vesselFerryCoastal container ship (up to ~5,000 gt)Small bulk carrierWorkboat / tug‑assist craft
Decision Guide: Choose if: you need a robust, compact stern thruster delivering up to 30 kN for vessels under 6,000 gt where space is limited and low‑speed maneuverability is critical. Avoid if: the vessel requires higher thrust levels for large DP systems, or if class societies demand proven certification that is not yet documented for this model.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
XM-TT-300 bow
unverified
· 300.0 kW
· High-efficiency tunnel thruster
Power (kW)
300
Thrust (kN)
36.0
Diameter (mm)
740
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust (36 kN) relative to its 300 kW power gives an excellent thrust‑to‑power ratio.
- Large 740 mm duct diameter improves water flow and reduces cavitation, enhancing reliability.
- Compact integrated motor‑pump unit simplifies installation and retrofits on existing bows.
- Low noise and vibration design suitable for passenger‑oriented vessels.
- Compatible with standard bridge control interfaces (joystick, IBSS).
Weaknesses
- Requires a substantial 300 kW electrical supply and associated cooling infrastructure.
- The 740 mm duct size can limit placement on smaller bows or vessels with tight space constraints.
- Higher initial capital cost compared with lower‑power thruster options.
- Maintenance access may be difficult due to bow location and surrounding hull structures.
- Hull reinforcement may be needed to accommodate the high thrust loads.
Typical Vessels:
Container shipBulk carrierRo‑Ro ferryCruise linerOffshore supply vessel
Decision Guide: Choose if: you need strong low‑speed manoeuvring on a large vessel, have sufficient bow space for a 740 mm duct, and can provide the required electrical power. Avoid if: vessel size or bow geometry restricts large thruster installations, or the ship’s power plant cannot support a 300 kW unit without major upgrades.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
XM-TT-300 stern
unverified
· 300.0 kW
· tunnel thruster
Power (kW)
300
Thrust (kN)
36.0
Diameter (mm)
740
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (36 kN) suitable for large ships' stern assistance
- Robust tunnel housing provides protection against debris and fouling
- Standard 740 mm duct size fits many existing hull designs without major modifications
- Direct‑drive motor offers good efficiency at full power
Weaknesses
- Fixed‑direction thrust limits maneuverability compared with azimuth units
- Large tunnel diameter occupies significant hull space, affecting internal layout
- Potential for cavitation noise at high RPM if not properly matched to propeller design
- Installation requires precise alignment and sealing to avoid water ingress
Typical Vessels:
Container shipBulk carrierCrude oil tankerLiquefied gas carrierCruise linerOffshore supply vessel
Decision Guide: Choose if: you need a high‑thrust, reliable stern thruster for large commercial vessels and have sufficient hull space for a 740 mm tunnel. Avoid if: you require 360° thrust vectoring, minimal hull intrusion, or ultra‑low acoustic signature.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
XM-TT-400 bow
unverified
· 400.0 kW
· high‑thrust tunnel thruster
Power (kW)
400
Thrust (kN)
48.0
Diameter (mm)
820
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (48 kN at 400 kW) gives strong low‑speed manoeuvring capability
- Relatively compact duct diameter (820 mm) eases integration in existing hull forms
- Robust stainless‑steel construction and sealed bearing system reduce corrosion risk in marine environments
- Integrated variable‑frequency drive allows precise thrust control and energy efficiency
Weaknesses
- 400 kW power demand requires substantial electrical supply and cooling capacity
- Large duct size may limit installation on vessels with narrow bow sections or retrofits
- Potential for cavitation at high RPMs, requiring careful propeller design and monitoring
- Maintenance of the sealed bearing assembly can be more involved than for simpler azimuth units
Typical Vessels:
Container ships (>30 000 dwt)Cruise linersOffshore supply vesselsLNG carriersLarge Ro‑Ro ferries
Decision Guide: Choose if: you need a high‑thrust bow thruster for vessels >30 000 dwt, have sufficient electrical generation capacity, and value a compact duct that fits within limited bow space. Avoid if: the vessel has severe space constraints in the bow, operates primarily at very low power where a smaller thruster would suffice, or you lack the infrastructure to support 400 kW of continuous load.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
XM-TT-400 stern
unverified
· 400.0 kW
· tunnel thruster
Power (kW)
400
Thrust (kN)
48.0
Diameter (mm)
820
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (48 kN) suitable for large vessels
- Relatively compact duct diameter (820 mm) reduces hull penetration area
- Direct‑drive 400 kW motor provides efficient power conversion
- Robust tunnel design offers good protection against debris and grounding impacts
Weaknesses
- High electrical power demand (400 kW) requires substantial onboard supply capacity
- Potential for cavitation at high blade speeds, especially in shallow water
- Maintenance of bearing and seal assemblies can be intensive on heavily used vessels
- Fixed‑direction thrust limits flexibility compared with azimuth or pod thrusters
Typical Vessels:
Container shipBulk carrierCruise linerOffshore supply vesselLNG/LPG carrier (mid‑size)
Decision Guide: Choose if: you need a high‑thrust stern thruster for vessels up to ~150 000 dwt, have sufficient electrical generation capacity, and operate mainly in ports where fixed‑direction thrust is adequate. Avoid if: low noise, minimal maintenance, or full 360° thrust capability (azimuth) are higher priorities.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
XM-TT-500 bow
unverified
· 500.0 kW
· tunnel thruster
Power (kW)
500
Thrust (kN)
60.0
Diameter (mm)
900
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (≈60 kN) suitable for medium‑large vessels
- Large 900 mm tunnel diameter provides efficient water flow and reduced cavitation risk at design load
- Compact bow installation frees deck space compared to external azimuth units
- Integrated control interface compatible with most ship bridge systems
Weaknesses
- 500 kW power demand increases fuel consumption and requires robust electrical supply
- Large tunnel size may limit applicability on vessels with restricted hull girth or shallow draft
- Maintenance of bearings, seals and cooling system can be intensive in high‑usage scenarios
- Potential for cavitation if operated continuously at full thrust in low‑speed water
Typical Vessels:
Container shipBulk carrierProduct tankerCruise linerOffshore supply vessel
Decision Guide: Choose if: you need strong bow thrust for vessels >15,000 DWT operating in congested ports or requiring dynamic positioning. Avoid if: hull geometry limits tunnel diameter, power budget is tight, or a lower‑cost azimuth pod meets the maneuverability requirement.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
XM-TT-500 stern
unverified
· 500.0 kW
· tunnel thruster
Power (kW)
500
Thrust (kN)
60.0
Diameter (mm)
900
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (60 kN) relative to its 500 kW power rating
- Large 900 mm tunnel diameter provides efficient water flow and reduces cavitation risk
- Stern installation enhances manoeuvrability during docking and low‑speed operations
- Compact, self‑contained unit suitable for retrofits without major hull alterations
Weaknesses
- Requires substantial hull penetration for the 900 mm tunnel, limiting use on thin‑walled or small vessels
- High power demand (≈500 kW) increases fuel consumption or electrical load
- Tunnel depth may be unsuitable for very shallow‑draft ships
- Maintenance of bearings and seals can be intensive due to high thrust loads
Typical Vessels:
Container ShipProduct TankerBulk CarrierOffshore Supply VesselCruise Ship
Decision Guide: Choose if you need strong stern‑side thrust for precise docking, have sufficient hull space for a 900 mm tunnel and can supply ~500 kW power. Avoid if the vessel is shallow‑draft, has limited hull thickness, or if an azimuth thruster offers better manoeuvrability for your operational profile.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
XM-TT-600 bow
unverified
· 600.0 kW
· Tunnel thruster
Power (kW)
600
Thrust (kN)
72.0
Diameter (mm)
980
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (72 kN) relative to its compact 980 mm diameter, suitable for medium‑large vessels
- Integrated 600 kW electric drive provides rapid response and fine speed control
- Bow placement enhances docking and close‑quarter maneuverability
- Proven tunnel design offers good protection against fouling and impact
Weaknesses
- High power demand (600 kW) may require substantial shore‑side electrical infrastructure
- Installation in the bow can be space‑constrained on vessels with limited hull volume
- Large duct size may limit applicability to smaller ships or those with narrow bow sections
- No publicly documented certifications; verification required for class approval
Typical Vessels:
Container shipBulk carrierProduct tankerCruise linerOffshore support vessel
Decision Guide: Choose if: you need strong bow thrust for vessels up to ~150 m LOA where a 1‑metre duct fits and the ship’s power plant can supply 600 kW. Avoid if: electrical generation capacity is limited, hull geometry cannot accommodate a near‑1‑metre tunnel, or class societies require specific certified thruster types not yet listed for this model.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
XM-TT-600 stern
unverified
· 600.0 kW
· tunnel thruster
Power (kW)
600
Thrust (kN)
72.0
Diameter (mm)
980
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (72 kN) relative to power rating, suitable for large ships
- Large 980 mm tunnel diameter reduces cavitation and improves efficiency
- Robust stern installation provides strong lateral control during docking and low‑speed maneuvers
- Compact integration compared with azimuth pods, lowering upfront cost
Weaknesses
- Significant hull penetration required for the 980 mm tunnel, affecting structural design
- High power consumption (600 kW) increases fuel use when operated frequently
- Limited to stern placement; not usable as a bow thruster without redesign
- Maintenance access can be difficult due to location and size of the tunnel
Typical Vessels:
Container shipBulk carrierTankerCruise linerOffshore supply vessel
Decision Guide: Choose if: you need a high‑thrust stern thruster for vessels >30,000 gt where cost and simplicity are priorities; the ship’s hull can accommodate a ~1 m tunnel. Avoid if: space constraints prevent a large tunnel, or 360° thrust vectoring (azimuth) is required for dynamic positioning.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
XM-TT-750 bow
unverified
· 750.0 kW
· high‑power tunnel thruster
Power (kW)
750
Thrust (kN)
90.0
Diameter (mm)
1100
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (≈90 kN) for a relatively compact 1.1 m duct diameter
- Suitable for vessels that require powerful bow assistance during docking and undocking
Weaknesses
- Large power rating may demand substantial electrical supply infrastructure
- Installation space requirements can be limiting on smaller hull forms
Typical Vessels:
Container shipBulk carrierTankerCruise liner
Decision Guide: Choose if the vessel needs >80 kN of bow thrust for safe port manoeuvring and has sufficient electrical capacity. Avoid on smaller ships where space or power constraints make a lower‑rated thruster more appropriate.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
XM-TT-750 stern
unverified
· 750.0 kW
· tunnel thruster
Power (kW)
750
Thrust (kN)
90.0
Diameter (mm)
1100
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (90 kN) suitable for large ships requiring strong lateral force
- Large 1100 mm duct provides efficient water flow and reduced cavitation risk
- 750 kW motor delivers ample power for rapid response during docking or DP operations
- Robust construction typical of XEAMOS Marine equipment, designed for harsh marine environments
Weaknesses
- Physical size (1.1 m diameter) limits installation on vessels with restricted stern space
- High electrical demand (750 kW) may require upgraded shipboard power distribution
- Larger bearing and seal assemblies can increase routine maintenance workload
- Weight and structural integration requirements are higher than smaller thrusters
Typical Vessels:
Container shipsBulk carriersCruise linersOffshore supply vesselsLNG/LPG carriers
Decision Guide: Choose if the vessel needs high stern thrust for tight berthing, dynamic positioning, or maneuvering in confined ports; avoid if space, power budget, or weight constraints preclude a large‑diameter thruster.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
XM-TT-800 bow
unverified
· 800.0 kW
· tunnel thruster
Power (kW)
800
Thrust (kN)
96.0
Diameter (mm)
1140
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (96 kN) suitable for vessels >100 kt deadweight
- Compact tunnel diameter (1140 mm) reduces hull penetration and internal space loss
- Integrated control electronics from XEAMOS provide smooth, low‑noise operation
- Designed for 800 kW input – good thrust‑to‑power ratio for its class
- Proven track record on offshore support vessels and cruise ships
Weaknesses
- Large power rating (800 kW) requires substantial electrical supply and cooling capacity
- Installation demands precise hull reinforcement, increasing dock‑time and cost
- Higher maintenance intervals compared with smaller thrusters due to wear on larger impeller blades
- Spare‑part availability may be limited in remote ports without XEAMOS service network
- Noise and vibration levels can be higher than low‑speed ducted propellers if not properly isolated
Typical Vessels:
Cruise shipsOffshore supply vessels (OSV)Large container vessels (up to ~10 000 TEU)Bulk carriers (>70 kt)Tugboats and high‑power workboats
Decision Guide: Choose if you need a powerful bow thruster for vessels above 100 kt deadweight that require tight port manoeuvring, have sufficient electrical generation capacity, and value integrated control systems. Avoid if the ship’s power plant cannot comfortably supply 800 kW to a single thruster, hull space is severely constrained, or operating in regions where XEAMOS after‑sales support is scarce.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
XM-TT-800 stern
unverified
· 800.0 kW
· tunnel thruster
Power (kW)
800
Thrust (kN)
96.0
Diameter (mm)
1140
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (96 kN) suitable for large ships and tight port maneuvers
- Compact tunnel layout saves deck space compared with azimuth pods
- Integrated cooling system handles continuous high‑power operation
- Low acoustic signature relative to conventional propeller‑type thrusters
- Robust construction for harsh marine environments
Weaknesses
- High electrical power demand (800 kW) may require vessel power‑system upgrades
- Installation requires significant hull penetration and structural reinforcement
- Maintenance of large bearing assemblies can be labour‑intensive
- Potential cavitation at maximum thrust in shallow water
- Limited azimuth capability – fixed direction only
Typical Vessels:
Crude oil tankerContainer shipBulk carrierCruise linerOffshore supply vessel
Decision Guide: Choose if: you need a high‑thrust, space‑efficient stern thruster for vessels >30 000 gt that operate in confined ports or require DP assistance. Avoid if: the ship’s power plant cannot accommodate an extra 800 kW load, or a lower‑cost, lower‑power thruster would meet maneuvering requirements.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
XM-TT-1000 bow
unverified
· 1000.0 kW
· tunnel thruster
Power (kW)
1000
Thrust (kN)
120.0
Diameter (mm)
1300
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High power (1 MW) and thrust (120 kN) suitable for large ships
- Relatively compact tunnel diameter (1300 mm) for its power class
- Robust tunnel design reduces cavitation risk at high thrust levels
- Integrated control interface compatible with most ship bridge systems
Weaknesses
- Significant electrical power demand requiring dedicated generator capacity
- Installation space requirements may be limiting on vessels with narrow bow sections
- Maintenance access can be challenging due to the size of the tunnel housing
- Potential for increased vibration and noise compared with smaller thrusters
Typical Vessels:
Container ships (≥80,000 DWT)Cruise linersLNG/LPG carriersOffshore supply vesselsLarge bulk carriers
Decision Guide: Choose if: you need strong bow thrust for vessels >80,000 DWT operating in congested ports or requiring dynamic positioning assistance. Avoid if: hull space is limited, power generation capacity is insufficient, or a lower‑power thruster would meet maneuverability needs.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
XM-TT-1000 stern
unverified
· 1000.0 kW
· electric tunnel thruster
Power (kW)
1000
Thrust (kN)
120.0
Diameter (mm)
1300
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Provides up to 120 kN of thrust for strong stern maneuverability
- High installed power (1 MW) enables rapid response in tight port situations
- Large 1.3 m tunnel diameter promotes efficient water flow and reduces cavitation risk
Weaknesses
- Significant electrical power demand (≈1 MW) increases vessel generation load
- Physical size of the 1.3 m duct may require substantial hull modifications
- High thrust units generally have higher acquisition and maintenance costs
Typical Vessels:
Container shipBulk carrierTankerCruise linerOffshore supply vessel
Decision Guide: Choose if the vessel requires strong stern thrust for docking, berthing or dynamic positioning and has sufficient electrical generation capacity. Avoid if hull space is limited, power generation is constrained, or budget constraints preclude a high‑cost thruster.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
XM-TT-1200 bow
unverified
· 1200.0 kW
· tunnel thruster
Power (kW)
1200
Thrust (kN)
144.0
Diameter (mm)
1460
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (144 kN) suitable for precise bow handling on large ships
- Large duct diameter (1460 mm) reduces cavitation and improves efficiency
- Integrated bow location enhances low‑speed maneuvering and dynamic positioning
- 1200 kW power rating matches the requirements of high‑displacement vessels
Weaknesses
- Significant power consumption may increase fuel use or require dedicated generators
- Large physical size (1.46 m diameter) demands substantial hull penetration space
- Higher acoustic and vibration levels compared with smaller thrusters
- Installation and maintenance costs are higher due to the high‑power rating
Typical Vessels:
TankerContainer shipBulk carrierCruise linerOffshore supply vessel
Decision Guide: Choose if: you need a high‑thrust bow thruster for vessels over 30,000 gt that require precise low‑speed control or dynamic positioning. Avoid if: the ship is small to medium size, power budget is limited, or hull space cannot accommodate a 1.46 m duct.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
XM-TT-1200 stern
unverified
· 1200.0 kW
· tunnel thruster
Power (kW)
1200
Thrust (kN)
144.0
Diameter (mm)
1460
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- 1200 kW motor provides a high thrust output of 144 kN for rapid stern maneuvering
- Large 1460 mm duct diameter gives good hydraulic efficiency and reduced cavitation risk
- Designed specifically for stern installation, improving reverse‑direction control during docking
- Robust construction typical of XEAMOS units offers long service intervals
Weaknesses
- High power rating (1200 kW) increases electrical load and may affect ship’s power management
- Duct size requires substantial hull penetration space, limiting applicability on smaller ships
- Installation complexity is higher for stern locations compared with bow thrusters
- Routine maintenance of bearings and seals is required to sustain performance
Typical Vessels:
LNG CarrierCruise ShipOffshore Supply VesselContainer ShipBulk Carrier
Decision Guide: Choose if the vessel needs high stern thrust for tight port manoeuvring, has sufficient hull space for a 1.46 m duct and can accommodate a 1200 kW power supply. Avoid on smaller vessels or where electrical generation capacity is limited.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
XM-TT-1500 bow
unverified
· 1500.0 kW
· tunnel bow thruster
Power (kW)
1500
Thrust (kN)
180.0
Diameter (mm)
1700
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- 1500 kW motor provides very high thrust (180 kN) suitable for large vessels
- Large 1.7 m tunnel diameter gives excellent flow capacity and reduced cavitation risk at design point
- Tunnel layout protects the propeller from fouling and hull impact, lowering maintenance frequency
- Integrated control system compatible with most bridge‑integrated maneuvering packages
Weaknesses
- Physical size (1.7 m tunnel) limits installation on smaller hulls or retrofits
- High power demand requires robust shipboard electrical supply and cooling infrastructure
- Initial capital cost is higher than lower‑power thrusters
- Potential for increased vibration and noise at full thrust if not properly isolated
Typical Vessels:
VLCC / LR2 tankerULCV container shipCruise linerOffshore supply vessel (OSV)FPSO
Decision Guide: Choose if: you need very high bow‑thruster thrust for a large vessel operating in tight ports or under strong wind/current conditions, and the hull can accommodate a 1.7 m tunnel. Avoid if: vessel size or power plant cannot support the 1500 kW rating, or space constraints make a smaller thruster more practical.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
XM-TT-1500 stern
unverified
· 1500.0 kW
· tunnel thruster
Power (kW)
1500
Thrust (kN)
180.0
Diameter (mm)
1700
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (180 kN) suitable for large ships and DP operations
- Large 1.7 m tunnel diameter reduces cavitation and improves efficiency
- 1500 kW motor provides ample power reserve for demanding maneuvers
- Modular stern‑mount design simplifies installation on new builds
- Robust construction typical of XEAMOS Marine equipment, offering long service life
Weaknesses
- Large physical size limits use on smaller hulls or vessels with tight space constraints
- High power rating leads to greater fuel consumption when operated frequently
- Significant hull penetration required, increasing installation complexity and potential for leaks if not fitted correctly
- Maintenance access can be challenging due to the stern location and tunnel geometry
- Spare‑part availability may be limited outside of XEAMOS’s primary service network
Typical Vessels:
Container ship (≥8,000 TEU)Crude oil tanker (VLCC/ULCC)LNG carrierCruise linerOffshore supply vessel
Decision Guide: Choose if: you need high‑thrust stern maneuvering for a large vessel, operate in restricted ports or require DP assistance, and have sufficient hull space for a 1.7 m tunnel. Avoid if: the ship is small to medium size, weight/space constraints are critical, or you prefer a lower‑power, more compact thruster solution.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
XM-TT-2000 bow
unverified
· 2000.0 kW
· high‑power tunnel thruster
Power (kW)
2000
Thrust (kN)
240.0
Diameter (mm)
2100
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Rated 2000 kW providing a high thrust output of 240 kN for rapid bow maneuvers
- Compact tunnel integration reduces deck space compared with external azimuth units
- Robust sealed motor design limits exposure to seawater and lowers routine maintenance
- Large 2100 mm duct diameter supports efficient water flow at high power levels
Weaknesses
- High electrical demand may require vessel‑wide power system upgrades
- Large tunnel size can limit installation on vessels with restricted hull space or shallow draft
- Potential for cavitation and noise at full‑load conditions
- Installation and alignment are complex, requiring precise hull modifications
Typical Vessels:
Very Large Crude Carrier (VLCC)Ultra‑Large Container Vessel (ULCV)Cruise ShipOffshore Support VesselLarge Bulk Carrier
Decision Guide: Choose if: the vessel exceeds 80 000 DWT and needs strong bow thrust for port entry, dynamic positioning or emergency maneuvering, and hull geometry can accommodate a ~2.1 m tunnel. Avoid if: the ship is small, has limited draft clearance, or power generation capacity cannot support a 2 MW thruster.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
XM-TT-2000 stern
unverified
· 2000.0 kW
· high‑power ducted tunnel thruster
Power (kW)
2000
Thrust (kN)
240.0
Diameter (mm)
2100
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Provides very high thrust (≈240 kN) suitable for large tankers, container ships and bulk carriers.
- Robust ducted design offers good protection against debris and cavitation erosion.
- Integrated control electronics compatible with most ship bridge systems.
- Relatively compact footprint compared with comparable azimuth thrusters of the same power rating.
Weaknesses
- Electrical demand around 2 MW requires substantial onboard power generation capacity.
- Large tunnel diameter (≈2.1 m) necessitates significant hull penetration and structural reinforcement.
- Maneuverability is limited to thrust direction along the ship’s centreline; no 360° rotation like azimuth units.
- Noise and vibration levels can be higher at full power, requiring additional acoustic mitigation.
Typical Vessels:
Crude oil tankerProduct tankerContainer vessel (≥8 000 TEU)Bulk carrier (≥150 kt)Cruise ship
Decision Guide: Choose the XM‑TT‑2000 if you need a high‑thrust, reliable stern thruster for large vessels where hull space allows a ~2.1 m tunnel and sufficient electrical supply is available. Avoid it on ships with tight hull constraints, limited power generation, or when 360° thrust vectoring (azimuth) is required for precise positioning.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
XM-TT-2500 bow
unverified
· 2500.0 kW
· tunnel thruster
Power (kW)
2500
Thrust (kN)
300.0
Diameter (mm)
2500
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (≈300 kN) suitable for mega‑size ships and DP operations
- Integrated water‑cooling system allows continuous high‑power operation
- Modular motor/propeller design simplifies installation and future upgrades
- Advanced digital control interface with remote monitoring
Weaknesses
- Large duct diameter (≈2.5 m) limits fit on vessels with restricted hull space
- High power demand increases onboard electrical load and fuel consumption
- Installation requires substantial structural reinforcement of the bow section
- Maintenance access can be difficult due to size and location
Typical Vessels:
Container ship (≥10,000 TEU)Crude oil tanker (VLCC)LNG carrierCruise linerOffshore support vessel with DP
Decision Guide: Choose if the vessel needs maximum bow thrust for port entry/exit or dynamic positioning and can accommodate a 2.5 m duct. Avoid on smaller ships, vessels with tight hull geometry, or when budget constraints limit high‑power electrical systems.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
XM-TT-2500 stern
unverified
· 2500.0 kW
· tunnel thruster
Power (kW)
2500
Thrust (kN)
300.0
Diameter (mm)
2500
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (300 kN) suitable for large ships and tight port operations
- Large 2.5 m duct diameter reduces cavitation risk at high power levels
- Robust tunnel construction provides good protection against debris and grounding impacts
- Stern placement enhances aft‑end control during docking and low‑speed maneuvers
Weaknesses
- Physical size limits installation on vessels with restricted hull space or narrow stern sections
- High power demand (2.5 MW) requires substantial electrical generation capacity
- Installation and maintenance of a large tunnel duct can be cost‑intensive
- Potentially higher acoustic signature compared with smaller thrusters
Typical Vessels:
Very Large Crude Carrier (VLCC)Ultra Large Container Vessel (ULCV)Cruise shipOffshore supply vesselLarge bulk carrier
Decision Guide: Choose if the vessel needs very high aft thrust for precise docking, dynamic positioning or emergency stopping and has sufficient onboard power and space for a 2.5 m tunnel unit. Avoid if the ship is size‑restricted, power‑limited, or cost‑sensitive where a smaller thruster would meet requirements.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
XM-TT-3000 bow
unverified
· 3000.0 kW
· tunnel bow thruster
Power (kW)
3000
Thrust (kN)
360.0
Diameter (mm)
2900
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (360 kN) suitable for large vessels requiring strong lateral forces.
- Large tunnel diameter (2.9 m) provides efficient water flow and reduced cavitation risk at high power levels.
- 3000 kW rating enables rapid response for tight port entries or dynamic positioning support.
- Compact installation relative to equivalent azimuth thrusters when hull space permits a bow tunnel.
Weaknesses
- Large hull penetration required; may limit applicability on vessels with restricted bow space.
- Higher power consumption compared with lower‑rated tunnel units, impacting fuel efficiency during prolonged use.
- Maintenance access can be challenging due to the size of the tunnel and propeller assembly.
- Potential for increased vibration and noise transmission into the ship structure if not properly isolated.
Typical Vessels:
Container ships (>150 m LOA)Cruise linersLNG carriersOffshore supply vesselsLarge bulk carriers
Decision Guide: Choose if the vessel demands very high bow‑side thrust for maneuvering in confined ports, dynamic positioning, or emergency stop capability and has sufficient bow space for a 2.9 m tunnel. Avoid if hull geometry restricts large tunnel installations, if fuel economy is a primary concern, or when a smaller, lower‑power thruster would meet the operational requirements.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
XM-TT-3000 stern
unverified
· 3000.0 kW
· tunnel thruster
Power (kW)
3000
Thrust (kN)
360.0
Diameter (mm)
2900
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust output (360 kN) for its power rating, enabling rapid lateral movement.
- Large 2.9 m tunnel diameter reduces cavitation and improves hydraulic efficiency.
- Robust construction suited to stern installation on large commercial ships.
- Provides precise control for docking, low‑speed maneuvering and dynamic positioning.
Weaknesses
- High power demand (3 MW) leads to significant fuel consumption when operated continuously.
- Large physical size requires ample hull space and structural reinforcement at the stern.
- Higher initial capital cost compared with smaller or azimuth thrusters.
- Installation complexity may increase dry‑dock time.
Typical Vessels:
Very Large Crude Carrier (VLCC)Container ship (>150 m LOA)Cruise linerOffshore supply vesselRo‑Ro ferry
Decision Guide: Choose if the vessel needs >300 kN of stern thrust for tight berthing, dynamic positioning or emergency maneuvering on a large hull. Avoid if space at the stern is limited, power budget is low, or a more compact azimuth thruster would meet the performance requirement.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
XM-TT-3500 bow
unverified
· 3500.0 kW
· high‑power tunnel thruster
Power (kW)
3500
Thrust (kN)
420.0
Diameter (mm)
3300
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (420 kN) suitable for vessels >200 m LOA
- Robust tunnel design reduces cavitation and improves reliability
- Integrated bow location enhances docking/undocking control
- Modular mounting allows retrofit on existing hulls
- Compatible with 3500 kW electric drive systems common in modern ships
Weaknesses
- Large tunnel diameter (3.3 m) requires significant hull penetration and internal space
- High power demand (3.5 MW) increases fuel/electric consumption
- Installation depth limits use on shallow‑draft vessels
- Maintenance access can be challenging due to size of the tunnel
- Capital cost is typically higher than lower‑power thrusters
Typical Vessels:
Very Large Crude Carrier (VLCC)LNG carrierCruise shipOffshore supply vesselLarge container ship (>200 m)
Decision Guide: Choose if: you need maximum bow thrust for a large vessel, have sufficient hull space for a 3.3 m tunnel, and can accommodate the 3.5 MW power requirement. Avoid if: the ship is small or shallow‑draft, budget constraints limit high‑power installations, or maintenance accessibility is a primary concern.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
XM-TT-3500 stern
unverified
· 3500.0 kW
· high-power tunnel thruster
Power (kW)
3500
Thrust (kN)
420.0
Diameter (mm)
3300
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (420 kN) suitable for large ships and tight port operations
- Large 3.3 m duct diameter improves hydraulic efficiency and reduces cavitation risk
- Designed for stern installation, enhancing aft steering control during docking and DP maneuvers
- Robust construction typical of XEAMOS Marine equipment, offering long service intervals
- High power rating (3 500 kW) provides ample margin for demanding manoeuvring tasks
Weaknesses
- Large physical size requires significant hull penetration and space in the stern
- High electrical demand (3.5 MW) may necessitate upgrades to ship power distribution
- Installation and maintenance costs are higher than smaller thruster options
- Potential for increased noise and vibration if not properly isolated
- Not suitable for vessels with limited beam or shallow draft constraints
Typical Vessels:
Container ShipBulk CarrierTankerCruise ShipOffshore Support Vessel
Decision Guide: Choose if: you need a very high‑thrust stern thruster for vessels over ~150 m LOA, operating in congested ports or requiring dynamic positioning. Avoid if: the vessel has limited stern space, low power availability, or operates primarily in shallow waters where a smaller thruster is more appropriate.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
XM-TT-4000 bow
unverified
· 4000.0 kW
· tunnel thruster
Power (kW)
4000
Thrust (kN)
480.0
Diameter (mm)
3700
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (480 kN) suitable for large ships and DP operations
- Large duct diameter reduces cavitation risk at high power levels
- Compact tunnel installation frees deck space compared to azimuth units
- Integrated control system compatible with most bridge consoles
Weaknesses
- High electrical demand (≈4 MW) may require substantial generator capacity
- Physical size of the duct (3.7 m) limits fit in vessels with restricted hull openings
- Potential for increased acoustic noise and vibration at full power
- Installation and maintenance access can be challenging in tight bow sections
Typical Vessels:
LNG CarrierCruise ShipOffshore Supply VesselLarge Container ShipBulk Carrier (>150 kt)
Decision Guide: Choose if the vessel needs high bow thrust for tight port manoeuvring, dynamic positioning or emergency stopping and has sufficient power generation capacity. Avoid if hull space is limited, power budget is low, or noise/vibration constraints are critical.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
XM-TT-4000 stern
unverified
· 4000.0 kW
· high‑thrust tunnel thruster
Power (kW)
4000
Thrust (kN)
480.0
Diameter (mm)
3700
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (480 kN) suitable for large vessels and DP assistance
- Large 3700 mm tunnel diameter gives efficient water flow and reduced cavitation risk at design load
- Integrated control electronics compatible with most bridge systems
- Robust construction typical of XEAMOS marine‑grade alloys, designed for harsh sea conditions
- Stern placement improves reverse docking and maneuverability in confined ports
Weaknesses
- High power demand (4 MW) requires substantial onboard electrical capacity
- Large physical envelope (3.7 m tunnel) limits installation to vessels with sufficient hull space
- Installation involves significant hull penetration, increasing dry‑dock time and cost
- Potential for cavitation if operated beyond design point or in shallow water
- Maintenance of large bearings and seals can be more intensive than smaller thrusters
Typical Vessels:
Container ships (>8 000 TEU)Large bulk carriersCrude oil tankersLNG/LPG carriersCruise linersOffshore support vessels with DP capability
Decision Guide: Choose if: the vessel requires a high‑thrust stern thruster for reverse manoeuvring, dynamic positioning or tight‑port operations and can accommodate a 3.7 m tunnel and 4 MW power supply. Avoid if: the ship is small to medium size, has limited electrical generation capacity, or hull geometry cannot house such a large tunnel without major structural modifications.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
XM-TT-4500 bow
unverified
· 4500.0 kW
· high-power tunnel thruster
Power (kW)
4500
Thrust (kN)
540.0
Diameter (mm)
4100
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (540 kN) suitable for the largest merchant ships and cruise liners
- Large 4100 mm duct diameter reduces cavitation and improves hydraulic efficiency
- Integrated control interface compatible with dynamic positioning systems
- Compact bow installation compared with azimuth pods of similar power
- XEAMOS Marine’s reputation for robust mechanical design
Weaknesses
- Requires extensive hull penetration and structural reinforcement in the bow area
- High electrical demand (4.5 MW) may necessitate upgrades to ship power generation
- Large duct size limits installation on vessels with narrow or shallow bows
- Tunnel thrusters lose efficiency in very shallow water due to suction effects
- Maintenance access can be difficult because of the size and location
Typical Vessels:
Cruise ShipLNG CarrierLarge Container ShipBulk Carrier (large)Offshore Support Vessel
Decision Guide: Choose if: you need maximum bow thrust for a vessel over 150 m in length, operate in tight ports or require DP capability. Avoid if: hull space is limited, power plant cannot accommodate 4.5 MW demand, or the vessel operates primarily in very shallow waters where suction loss would be critical.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
XM-TT-4500 stern
unverified
· 4500.0 kW
· Tunnel thruster
Power (kW)
4500
Thrust (kN)
540.0
Diameter (mm)
4100
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (540 kN) suitable for mega‑vessels and dynamic positioning
- Robust tunnel design provides good protection against fouling and impact
- Large 4.1 m duct diameter enables efficient water flow at high power (4.5 MW)
- Integrated cooling system handles continuous operation during port stays
Weaknesses
- Significant hull penetration – requires careful structural reinforcement
- High power rating leads to greater fuel consumption and electrical load
- Installation space is large; may be unsuitable for vessels with limited stern width
- Maintenance access can be difficult due to the size of the duct
Typical Vessels:
Ultra‑large container shipsCrude oil tankers (VLCC)LNG carriersCruise linersOffshore supply vessels with DP capability
Decision Guide: Choose if you need maximum thrust for a large vessel, require a durable thruster that can operate continuously during port manoeuvring or DP, and have sufficient stern space for a 4.1 m duct. Avoid if hull reinforcement is limited, power supply constraints exist, or a more compact azimuth pod would better suit the vessel’s maneuvering profile.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
XM-TT-5000 bow
unverified
· 5000.0 kW
· tunnel thruster
Power (kW)
5000
Thrust (kN)
600.0
Diameter (mm)
4500
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (≈600 kN) suitable for mega‑vessels
- Large tunnel diameter (4.5 m) provides good flow efficiency
- Integrated control system compatible with DP and ship‑handling consoles
- Robust, marine‑grade construction designed for continuous port operations
Weaknesses
- High installed power requirement (≈5 MW) increases fuel consumption
- Large hull penetration demands extensive structural reinforcement
- Significant installation space and weight impact on vessel design
- Higher procurement and maintenance cost compared with lower‑power units
Typical Vessels:
VLCCULCV (Ultra Large Container Vessel)Cruise shipLNG carrierOffshore support vessel
Decision Guide: Choose if the vessel requires very high bow thrust for safe port entry/exit or dynamic positioning of a mega‑ship and can accommodate the power and structural demands. Avoid if the ship is smaller, has limited power budget, or space constraints that preclude a large tunnel installation.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
XM-TT-5000 stern
unverified
· 5000.0 kW
· tunnel thruster
Power (kW)
5000
Thrust (kN)
600.0
Diameter (mm)
4500
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high power rating (5 MW) delivering strong thrust for precise control
- Large 4.5 m tunnel diameter reduces cavitation risk at high loads
- Robust construction typical of XEAMS Marine equipment, suited to heavy‑duty service
- Integrated cooling and sealing systems designed for continuous DP operation
Weaknesses
- Large physical envelope limits installation on vessels with restricted stern space
- High electrical power demand may require substantial generator capacity
- Potentially higher acquisition and lifecycle cost compared with lower‑power units
- Complex maintenance due to size of impeller and bearing assemblies
Typical Vessels:
Container shipBulk carrierCruise linerOffshore supply vesselLNG carrier
Decision Guide: Choose if: you need maximum thrust for a large vessel’s stern, require reliable DP‑grade performance, and have sufficient electrical generation capacity. Avoid if: hull geometry restricts tunnel diameter, power plant cannot support 5 MW thruster load, or the maneuvering requirements are modest.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
YMV Marine
44
YMV-TT-50 bow
unverified
· 50.0 kW
· tunnel thruster
Power (kW)
50
Thrust (kN)
6.0
Diameter (mm)
540
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Provides 6 kN thrust at a relatively modest 50 kW power rating, giving good thrust‑to‑power efficiency for its size.
- Compact 540 mm tunnel diameter allows installation in vessels with limited hull space.
- Bow location enhances docking and low‑speed maneuverability without requiring stern thruster coordination.
Weaknesses
- Maximum thrust of 6 kN may be insufficient for larger ships or operations in strong currents/rough weather.
- 50 kW electrical demand can tax vessels with limited generator capacity, especially if multiple thrusters are installed.
- No publicly confirmed advanced features such as variable‑pitch blades, integrated condition monitoring, or hydraulic drive options.
Decision Guide: Choose if the vessel needs moderate bow thrust for precise docking, has limited hull space, and can supply a dedicated 50 kW electric source. Avoid if higher thrust (>10 kN) is required, the ship operates in heavy seas, or electrical power availability is constrained.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
YMV-TT-50 stern
unverified
· 50.0 kW
· tunnel thruster
Power (kW)
50
Thrust (kN)
6.0
Diameter (mm)
540
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Compact 540 mm tunnel fits into limited stern space on medium‑size vessels
- Reasonable thrust‑to‑power ratio (6 kN @ 50 kW) for vessels up to ~5,000 DWT
- Robust, low‑maintenance design typical of YMV Marine’s marine‑grade steel housings
- Straightforward integration with standard ship control and DP systems
Weaknesses
- Maximum thrust (6 kN) may be insufficient for larger vessels or high‑wind conditions
- Power demand (50 kW) can impact vessel electrical load on smaller ships
- Tunnel thrusters generate hull vibration and require periodic bearing inspection
- No publicly confirmed IMO/DNV certifications listed for this exact model
Typical Vessels:
Offshore Supply VesselCoastal FerrySmall Container / General Cargo ShipWorkboat / Tug (light‑duty)Cruise ship tender
Decision Guide: Choose if: you need a compact stern thruster delivering up to 6 kN for vessels under ~5,000 DWT, have limited installation space and prefer a proven YMV design with straightforward integration. Avoid if: the vessel requires higher thrust (>10 kN), operates in extreme weather where additional power reserve is critical, or you must meet specific class certifications that are not documented for this model.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
YMV-TT-75 bow
unverified
· 75.0 kW
· tunnel bow thruster
Power (kW)
75
Thrust (kN)
9.0
Diameter (mm)
560
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Compact 560 mm diameter fits vessels with limited hull space at the bow
- Moderate power demand (75 kW) suits ships with modest generator capacity
- Integrated nozzle design provides good thrust efficiency for its size
- Robust marine‑grade stainless steel construction typical of YMV Marine products
- Standard mounting arrangement simplifies installation and retro‑fit
Weaknesses
- Maximum thrust (9 kN) may be insufficient for high‑wind or strong‑current ports
- Lower thrust compared with larger 100 kW+ tunnel units
- Tunnel duct can accumulate debris if not regularly inspected
- Higher acoustic and vibration levels than some azimuth thrusters
- No variable‑pitch or controllable‑pitch option, limiting fine thrust modulation
Typical Vessels:
Offshore Supply VesselMultipurpose Platform Supply VesselCoastal Container ShipFerrySmall Bulk Carrier
Decision Guide: Choose if: you need a reliable, space‑efficient bow thruster for vessels up to ~10 kN thrust, have limited power availability, and operate mainly in moderate weather ports. Avoid if: the vessel requires higher thrust (>12 kN), operates frequently in severe wind/current conditions, or demands variable‑pitch control for fine positioning.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
YMV-TT-75 stern
unverified
· 75.0 kW
· tunnel thruster
Power (kW)
75
Thrust (kN)
9.0
Diameter (mm)
560
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (9 kN from 75 kW) improves manoeuvring efficiency
- Relatively small tunnel diameter (560 mm) fits vessels with limited hull space
- Robust, low‑maintenance tunnel construction common in marine environments
- Stern placement enhances docking control and reduces bow‑to‑sidewash effects
Weaknesses
- Maximum thrust of 9 kN may be insufficient for large tankers or ultra‑large vessels
- Compact tunnel can increase cavitation risk at high RPMs, potentially reducing efficiency
- Hull penetration required for installation introduces potential leakage points if not sealed correctly
- 75 kW power draw adds to overall ship electrical load, affecting fuel consumption on low‑power ships
Typical Vessels:
Offshore supply vesselRo‑Ro ferryCoastal container shipSmall bulk carrierMedium‑size tanker (up to ~30 kt deadweight)
Decision Guide: Choose if: you need a compact, high‑efficiency stern thruster for vessels up to about 150 m LOA where hull space is limited and 9 kN thrust meets manoeuvring requirements. Avoid if: the vessel requires higher thrust levels (>12 kN) or operates in extreme cavitation‑prone conditions that demand larger tunnel diameters.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
YMV-TT-100 bow
unverified
· 100.0 kW
· tunnel thruster
Power (kW)
100
Thrust (kN)
12.0
Diameter (mm)
580
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Delivers 12 kN thrust with only 100 kW input – good thrust‑to‑power ratio for its size
- Compact 580 mm tunnel diameter fits in vessels with limited hull space
- Bow location provides direct control during docking and low‑speed maneuvers
- Standardised mounting arrangement simplifies installation on new builds or retrofits
Weaknesses
- Maximum thrust may be insufficient for very large ships or high‑wind conditions
- Tunnel geometry can be prone to cavitation if operated at high RPMs in shallow water
- Requires regular inspection of duct seals and bearing wear to maintain performance
- Limited redundancy – a single unit provides all bow thrust
Typical Vessels:
Offshore supply vesselFerryContainer ship (up to ~10 000 gt)Cruise ship (mid‑size)Bulk carrier (small‑to‑medium)
Decision Guide: Choose if: you need a compact bow thruster delivering around 12 kN for vessels up to medium size, where hull space is limited and budget favours a 100 kW unit. Avoid if: higher thrust (>15 kN) or redundancy is required, or the vessel operates in conditions that may cause excessive cavitation.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
YMV-TT-100 stern
unverified
· 100.0 kW
· ducted tunnel thruster
Power (kW)
100
Thrust (kN)
12.0
Diameter (mm)
580
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust-to-power ratio (12 kN at 100 kW)
- Compact 580 mm duct diameter fits into limited hull space
- Stern placement provides effective astern handling and reduces interference with bow thrusters
- Modular design allows relatively quick installation and replacement
- Low vibration due to enclosed tunnel flow
Weaknesses
- 12 kN thrust may be insufficient for large vessels (>30,000 DWT) in strong currents or wind
- Tunnel geometry can be prone to cavitation at high load, requiring careful operation
- Limited access for maintenance when installed in the stern tunnel, potentially increasing downtime
- Requires a dedicated cooling water supply and filtration system
- Fixed‑pitch blades limit fine‑tuning of thrust compared with azimuth thrusters
Typical Vessels:
Product TankerHandymax Bulk CarrierOffshore Supply VesselFerrySmall Container Ship
Decision Guide: Choose if you need a cost‑effective, compact solution for improving astern maneuverability on vessels up to ~30 000 DWT and have sufficient hull space for a 580 mm tunnel. Avoid if the vessel requires higher thrust levels, operates in extreme weather, or needs 360° thrust vectoring.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
YMV-TT-150 bow
unverified
· 150.0 kW
· tunnel thruster
Power (kW)
150
Thrust (kN)
18.0
Diameter (mm)
620
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (18 kN) relative to modest power rating (150 kW)
- Large 620 mm duct diameter improves water flow efficiency and reduces cavitation risk
- Compact bow installation frees deck space for cargo handling equipment
- Tunnel design offers lower acoustic signature compared with external propeller units
- Suitable for vessels that require precise low‑speed positioning without full DP systems
Weaknesses
- Installation requires a hull penetration and sufficient draft to accommodate the duct depth
- Maintenance access can be limited, especially in confined bow sections
- Fixed thrust direction limits flexibility compared with azimuth or pod thrusters
- Power consumption may be higher than newer electric‑drive tunnel units of similar rating
- Not ideal for vessels that need very high thrust levels (>25 kN) for extreme maneuvering
Typical Vessels:
Offshore supply vesselRo‑Ro ferry (up to 5,000 GT)Container ship (up to ~10,000 TEU)Bulk carrier (up to ~20,000 DWT)General cargo ship
Decision Guide: Choose the YMV‑TT‑150 when a vessel needs reliable bow thrust for port entry/exit, tight berth handling, or limited DP capability and has sufficient draft for a tunnel duct. Avoid it on ships that require omnidirectional thrust, very high maneuvering forces, or where hull form does not permit a large bow tunnel.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
YMV-TT-150 stern
unverified
· 150.0 kW
· tunnel thruster
Power (kW)
150
Thrust (kN)
18.0
Diameter (mm)
620
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Provides 18 kN of thrust, sufficient for medium‑size vessels during berthing maneuvers
- Compact 620 mm tunnel diameter fits within many hull forms without excessive structural modification
- Stern location enhances aft maneuverability and reduces reliance on bow thrusters alone
- Tunnel design protects the propeller from fouling and impact damage
Weaknesses
- Fixed‑direction thrust; lacks the 360° steering capability of azimuth units
- 620 mm tunnel may be too large for smaller vessels or those with limited hull space
- Single unit provides no built‑in redundancy if a failure occurs
Typical Vessels:
Medium‑size tankerContainer ship (up to 8,000 TEU)Bulk carrier (up to 30 kt)Offshore supply vesselCruise ship (mid‑size)
Decision Guide: Choose if the vessel requires moderate aft thrust for docking and can accommodate a 620 mm tunnel diameter, and when a simple, robust solution is preferred over more complex azimuth thrusters. Avoid if higher thrust levels, full‑circle steering, or space constraints make a larger or azimuth unit more appropriate.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
YMV-TT-200 bow
unverified
· 200.0 kW
· electric tunnel thruster
Power (kW)
200
Thrust (kN)
24.0
Diameter (mm)
660
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (24 kN) relative to power rating, giving strong manoeuvring capability.
- Large 660 mm duct diameter provides efficient water flow and reduced cavitation risk.
- Compact bow‑mounting saves deck space compared with external azimuth units.
- Electric drive offers low vibration and easier integration with ship’s power management system.
Weaknesses
- Large duct size may limit installation on vessels with narrow hull forms or restricted bow space.
- Requires a substantial electrical supply (≈200 kW) and associated cooling infrastructure.
- Tunnel liners can be prone to wear and require periodic inspection/replacement.
- Fixed thrust direction; less versatile than rotating azimuth thrusters for certain DP operations.
Typical Vessels:
Offshore support vesselCruise shipContainer feederFerryLNG carrier (mid‑size)Bulk carrier (30–80 m)
Decision Guide: Choose the YMV‑TT‑200 if you need high bow thrust for tight berthing, have adequate electrical generation capacity, and prefer a compact tunnel solution that minimizes deck clutter. Avoid it on vessels with very narrow bows, limited power plant margin, or where a rotating azimuth thruster would provide greater maneuvering flexibility.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
YMV-TT-200 stern
unverified
· 200.0 kW
· tunnel thruster
Power (kW)
200
Thrust (kN)
24.0
Diameter (mm)
660
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust-to-power ratio (24 kN at 200 kW) for a compact unit
- Robust tunnel design with no exposed propeller, reducing fouling and damage risk
- Relatively simple installation in the stern tube with standard hull penetrations
- Low maintenance compared to azimuth or pod thrusters
Weaknesses
- Lower thrust efficiency at higher vessel speeds compared with azimuth units
- Potential for cavitation and increased noise under heavy load
- Limited maneuverability (fixed thrust direction) – cannot provide 360° vectoring
- Hull penetration required, which may affect structural integrity if not properly reinforced
Typical Vessels:
Handymax Bulk CarrierProduct Tanker (up to ~30,000 DWT)Container FeederOffshore Supply VesselMid‑size Cruise Ship
Decision Guide: Choose if: you need a cost‑effective, reliable stern thruster for vessels up to ~30 kt and moderate maneuvering requirements; space is limited and a fixed‑direction thrust device is acceptable. Avoid if: the vessel requires high thrust density, 360° thrust vectoring, or operates frequently at higher speeds where tunnel efficiency drops.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
YMV-TT-250 bow
unverified
· 250.0 kW
· tunnel bow thruster
Power (kW)
250
Thrust (kN)
30.0
Diameter (mm)
700
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (30 kN) relative to modest power rating (250 kW)
- Compact tunnel design fits within limited hull space at the bow
- Robust, low‑maintenance steel duct and impeller construction
- Integrated control interface compatible with most ship bridge systems
Weaknesses
- Requires hull penetration; installation can be invasive on existing vessels
- Limited thrust for very large ships (>150 m LOA) that may need >40 kN
- Potential cavitation at full‑load conditions, especially in shallow water
- Access for routine inspection is confined within the tunnel duct
Typical Vessels:
Container feederHandymax bulk carrierProduct tanker (small/medium)Offshore supply vesselCruise ship (mid‑size)
Decision Guide: Choose if: you need a reliable, high‑thrust bow thruster for medium‑sized vessels with limited space and want a proven tunnel design. Avoid if: the vessel exceeds the thrust envelope of 30 kN, or you prefer azimuth or pod‑type thrusters for full 360° maneuverability.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
YMV-TT-250 stern
unverified
· 250.0 kW
· tunnel thruster
Power (kW)
250
Thrust (kN)
30.0
Diameter (mm)
700
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (30 kN at 250 kW) for its size class
- Compact tunnel diameter (700 mm) fits in moderate‑size hulls without excessive structural modification
- Robust, sealed design reduces ingress of water and debris
- Relatively low acoustic signature compared with propeller‑type thrusters
Weaknesses
- Effectiveness drops sharply in strong cross‑winds or currents; may require supplemental bow thrusters on larger vessels
- Hull penetration required for installation, increasing potential for leaks if not properly sealed
- Maintenance access can be limited in tight stern spaces
- Fixed thrust direction limits flexibility versus azimuth (rotary) units
Typical Vessels:
Container ships up to ~30 000 dwtBulk carriers (handy‑size to panamax)General cargo vesselsOffshore supply and support vessels
Decision Guide: Choose if you need a reliable, high‑thrust stern thruster for vessels up to medium size where hull space is limited and a fixed thrust direction is acceptable. Avoid if the vessel operates in severe weather conditions, requires 360° thrust vectoring, or demands higher thrust levels than 30 kN.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
YMV-TT-300 bow
unverified
· 300.0 kW
· Tunnel thruster
Power (kW)
300
Thrust (kN)
36.0
Diameter (mm)
740
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (36 kN @ 300 kW) provides strong manoeuvring capability for medium‑size vessels.
- 740 mm tunnel diameter is relatively compact, limiting hull penetration and structural reinforcement needs.
- Standard 300 kW electric motor matches common shipboard power supplies, simplifying integration.
- Proven tunnel‑type design offers reliable operation with low maintenance compared to more complex azimuth units.
Weaknesses
- Tunnel geometry can generate cavitation noise at high RPMs, which may be a concern for passenger or offshore vessels.
- Hull penetration required for the tunnel may reduce internal volume and increase construction complexity.
- Less efficient than pod‑type thrusters when operating continuously at higher speeds or in strong currents.
- Limited thrust vectoring (fixed 90° orientation) compared with azimuth thrusters, reducing flexibility in tight berths.
Typical Vessels:
Medium tankers (up to ~30 000 dwt)Container ships (up to ~20 000 TEU)Bulk carriers (up to ~40 000 dwt)Offshore supply vesselsCruise ship tenders
Decision Guide: Choose the YMV‑TT‑300 when you need a high‑thrust, cost‑effective bow thruster for vessels in the 20–40 000 dwt range that operate primarily at low speeds or require dynamic positioning support. Avoid it on ships where hull space is at a premium, noise restrictions are strict, or continuous high‑speed thrust is required, as azimuth pods may be more suitable.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
YMV-TT-300 stern
unverified
· 300.0 kW
· tunnel thruster
Power (kW)
300
Thrust (kN)
36.0
Diameter (mm)
740
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (36 kN) relative to its power rating, suitable for vessels with demanding manoeuvring needs
- Compact 740 mm diameter allows installation on a wide range of hull forms without excessive structural modification
- Integrated hydraulic‑electric drive (typical for YMV units) offers good reliability and low maintenance
- Direct thrust at the stern improves turning radius and docking control, especially in confined ports
Weaknesses
- Large hull penetration required; installation can be costly and may affect structural integrity if not properly reinforced
- Potential cavitation and reduced efficiency when operating near full power for extended periods
- Power demand of 300 kW adds significantly to ship’s electrical load, requiring adequate generator capacity
- Performance drops in heavy sea states or strong cross‑winds compared with azimuth thrusters
Typical Vessels:
Offshore supply vesselCruise shipContainer feederRo‑Ro ferryMedium‑size bulk carrier
Decision Guide: Choose if: you need a high‑thrust stern thruster for vessels up to ~150 m LOA, have sufficient hull space for a 740 mm tunnel, and prefer a proven, low‑maintenance design. Avoid if: the vessel operates primarily in very rough seas, requires azimuthing thrust for dynamic positioning, or has strict weight/space constraints that favour smaller pod units.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
YMV-TT-400 bow
unverified
· 400.0 kW
· tunnel thruster
Power (kW)
400
Thrust (kN)
48.0
Diameter (mm)
820
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (48 kN) relative to its power rating, improving maneuverability in confined ports.
- Large 820 mm duct diameter promotes efficient water flow and reduces cavitation risk.
- Robust tunnel design protects the propeller from debris and hull impacts.
- Integrated bow placement aids in tight‑berth handling for vessels up to medium‑size bulk carriers and tankers.
Weaknesses
- Large duct size may require significant hull penetration and can affect hydrodynamic resistance when not in use.
- 400 kW power demand increases fuel consumption compared with lower‑rated thrusters on smaller ships.
- Installation space is limited to vessels that can accommodate an 820 mm tunnel, restricting retrofits on older hulls.
- Maintenance access to the internal propeller can be more involved than for external azimuth units.
Typical Vessels:
Bulk CarrierProduct TankerContainer Ship (up to ~30,000 DWT)Offshore Supply Vessel
Decision Guide: Choose if: you need strong bow‑side thrust for vessels up to medium size, have sufficient hull space for an 820 mm tunnel, and require a durable design that tolerates debris. Avoid if: the vessel is small with limited hull penetration allowance, or if fuel efficiency at low power is a primary concern.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
YMV-TT-400 stern
unverified
· 400.0 kW
· Tunnel thruster
Power (kW)
400
Thrust (kN)
48.0
Diameter (mm)
820
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (48 kN at 400 kW) gives excellent manoeuvring capability.
- Large 820 mm duct diameter promotes efficient water flow and reduces hydraulic losses.
- Stern placement improves control during berthing, backing out, and dynamic positioning.
- Robust construction typical of YMV Marine units offers long service life in harsh marine environments.
Weaknesses
- Relatively large installation footprint may limit use on vessels with constrained hull space.
- Higher power demand compared with smaller thrusters can increase fuel consumption.
- Potential for cavitation at maximum thrust if not properly aligned or maintained.
- Spare‑part availability may be limited if YMV Marine has a narrow dealer network.
Typical Vessels:
Container shipTankerBulk carrierOffshore supply vesselCruise linerFerry
Decision Guide: Choose if the vessel requires strong stern thrust for precise docking, backing maneuvers or dynamic positioning and has sufficient hull space and power margin. Avoid if installation area is limited, power budget is tight, or a lower‑cost, lower‑thrust solution suffices.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
YMV-TT-500 bow
unverified
· 500.0 kW
· tunnel thruster
Power (kW)
500
Thrust (kN)
60.0
Diameter (mm)
900
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust-to-power ratio (≈0.12 kN/kW) suitable for vessels requiring strong bow assistance
- Compact tunnel geometry fits standard 900 mm bow openings without excessive hull penetration
- Ducted flow reduces cavitation and improves efficiency at low speeds
- Proven tunnel‑type design offers reliable operation with minimal maintenance
- Integrated control interface compatible with most ship bridge systems
Weaknesses
- 500 kW power demand may strain vessels with limited generator capacity
- Large duct diameter can limit available bow space for other equipment or mooring gear
- Installation often requires structural reinforcement of the hull, increasing retrofit cost
- Noise and vibration levels higher than smaller‑capacity thrusters
- Effectiveness drops at speeds above 10 knots; not suitable as primary propulsion aid
Typical Vessels:
ContainerBulk CarrierTankerRo-RoOffshore Supply Vessel
Decision Guide: Choose if you need ≥60 kN bow thrust for vessels up to ~30,000 DWT, have sufficient power generation and space for a 900 mm tunnel, and require reliable low‑speed maneuverability or DP assistance. Avoid if the ship has tight bow geometry, limited electrical power, or operates primarily at higher speeds where thruster efficiency falls.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
YMV-TT-500 stern
unverified
· 500.0 kW
· ducted tunnel thruster
Power (kW)
500
Thrust (kN)
60.0
Diameter (mm)
900
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (60 kN) relative to its 500 kW power rating, suitable for large ships requiring strong stern maneuvering force.
- Compact 900 mm tunnel diameter allows installation on vessels with limited hull space while still providing effective flow control.
- Integrated stern design reduces the length of hull penetration compared with side‑mounted units, improving structural integrity.
- Robust construction typical of YMV Marine products offers good resistance to corrosion and impact in harsh marine environments.
Weaknesses
- 500 kW power demand can increase overall vessel fuel consumption and may require dedicated electrical supply capacity.
- The 900 mm tunnel size limits installation to vessels that can accommodate the required hull opening, restricting use on smaller ships.
- High thrust levels can generate cavitation noise and vibration if not properly matched to propeller‑wake conditions.
- Maintenance access is confined to the stern area, which may be more difficult during dry‑dock periods compared with side thrusters.
Typical Vessels:
Very Large Crude Carrier (VLCC)Container shipBulk carrierCruise linerOffshore supply vessel
Decision Guide: Choose if the vessel needs strong, reliable stern thrust for docking, low‑speed manoeuvring or DP assistance and has sufficient hull space for a 900 mm tunnel. Avoid on smaller ships where power consumption or tunnel size would be prohibitive, or when a lower‑cost side thruster can meet the maneuverability requirements.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
YMV-TT-600 bow
unverified
· 600.0 kW
· tunnel thruster
Power (kW)
600
Thrust (kN)
72.0
Diameter (mm)
980
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (72 kN) relative to power rating, improving port handling and DP capability.
- Compact tunnel layout fits within the hull without protruding appendages.
Weaknesses
- Large tunnel diameter (980 mm) may limit installation in vessels with restricted bow space.
- 600 kW power demand requires substantial electrical supply and cooling infrastructure.
Decision Guide: Choose if the vessel needs strong bow thrust for precise maneuvering or DP support and has sufficient hull volume for a ~1 m tunnel. Avoid if space is limited, power generation is constrained, or a lower‑thrust solution suffices.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
YMV-TT-600 stern
unverified
· 600.0 kW
· tunnel thruster
Power (kW)
600
Thrust (kN)
72.0
Diameter (mm)
980
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust (72 kN) relative to size, enabling strong lateral forces for docking and DP operations
- Compact tunnel geometry fits within a 980 mm hull opening, preserving deck space
- Integrated with YMV’s control system for smooth, low‑vibration operation
- Robust 600 kW motor suitable for continuous duty on large commercial ships
Weaknesses
- Significant power demand (600 kW) increases fuel consumption when used extensively
- Installation requires hull penetration and precise alignment, raising initial fit‑out cost
- Maintenance of bearings and seals can be demanding in high‑salinity environments
- Noise and cavitation may become noticeable at full thrust on smaller vessels
Typical Vessels:
Container shipCrude oil tankerBulk carrierCruise linerOffshore supply vessel
Decision Guide: Choose if you need a powerful stern thruster for vessels >30,000 gt that require strong lateral control during docking or dynamic positioning. Avoid if the ship’s power budget is limited, the hull cannot accommodate a ~1 m tunnel, or low‑noise operation is a primary requirement.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
YMV-TT-750 bow
unverified
· 750.0 kW
· tunnel bow thruster
Power (kW)
750
Thrust (kN)
90.0
Diameter (mm)
1100
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (90 kN) provides rapid side‑way movement for berthing and un‑berthing.
- 750 kW motor gives ample power for vessels above 30 000 gt, supporting dynamic positioning and emergency manoeuvres.
- Large 1.1 m tunnel diameter reduces pressure loss, improving hydraulic efficiency compared with smaller tunnels.
Weaknesses
- High power rating results in greater fuel consumption when the thruster is operated continuously.
- The 1.1 m tunnel requires substantial hull penetration and structural reinforcement, increasing installation complexity.
- Large physical size may limit fit on vessels with narrow bow sections or restricted internal space.
- At maximum thrust, cavitation risk rises in shallow water or low‑speed operation.
Typical Vessels:
TankerContainer shipBulk carrierCruise linerOffshore supply vessel
Decision Guide: Choose the YMV‑TT‑750 when a vessel needs high bow thrust for tight port manoeuvring, dynamic positioning or emergency side thrust and has sufficient bow space to accommodate a 1.1 m tunnel. Avoid it on smaller ships with limited hull volume, low power budgets, or where noise and fuel consumption must be minimised.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
YMV-TT-750 stern
unverified
· 750.0 kW
· tunnel thruster
Power (kW)
750
Thrust (kN)
90.0
Diameter (mm)
1100
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (90 kN) suitable for large vessels
- High installed power (750 kW) gives strong and rapid response
- Relatively compact 1.1 m tunnel diameter fits limited hull space
- Robust stainless‑steel housing typical of YMV Marine designs
Weaknesses
- High electrical/hydraulic power consumption
- Large hull opening required for the 1100 mm tunnel
- Maintenance access can be challenging on stern installations
Typical Vessels:
Crude oil tankerProduct tankerContainer shipBulk carrierCruise liner
Decision Guide: Choose if you need a powerful stern thruster for large vessels where hull space is limited and robust, low‑noise operation is required. Avoid if the vessel already uses azimuth or podded propulsion for maneuvering, or if power consumption must be minimized.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
YMV-TT-800 bow
unverified
· 800.0 kW
· tunnel thruster
Power (kW)
800
Thrust (kN)
96.0
Diameter (mm)
1140
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High installed power (800 kW) provides strong lateral thrust (96 kN).
- Large 1.14 m duct diameter promotes efficient water flow and reduces cavitation risk.
- Bow‑mounted configuration enhances docking and close‑quarter maneuverability on large ships.
Weaknesses
- Physical size of the 1.14 m tunnel requires significant hull penetration and internal space.
- High power consumption increases fuel use for auxiliary generators.
- Installation and maintenance are more complex than external azimuth thrusters due to shafting and bearing wear.
Typical Vessels:
Crude oil tankerContainer shipBulk carrierCruise linerOffshore supply vessel
Decision Guide: Choose if the vessel requires >90 kN of bow thrust for safe docking, has sufficient hull space for a large tunnel unit, and can accommodate the auxiliary power demand. Avoid if the ship is small‑to‑medium size, has limited internal volume, or prefers external azimuth thrusters for redundancy.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
YMV-TT-800 stern
unverified
· 800.0 kW
· tunnel thruster
Power (kW)
800
Thrust (kN)
96.0
Diameter (mm)
1140
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust (96 kN) suitable for vessels over 30 000 gt, improving docking and port handling.
- Large 1.14 m tunnel diameter gives good flow efficiency and reduced cavitation risk.
- Integrated control interface compatible with most ship bridge systems.
- Robust stainless‑steel construction typical of YMV Marine products, offering long service life in harsh marine environments.
Weaknesses
- Relatively large hull penetration (1.14 m) may limit installation on smaller ships or vessels with restricted hull space.
- 800 kW power demand requires substantial electrical supply and cooling capacity.
- Weight and mounting requirements are not publicly specified, potentially increasing retrofit complexity.
- No publicly available data on noise levels; could be a concern for passenger‑oriented vessels.
Typical Vessels:
Container shipBulk carrierCrude oil tankerLiquefied gas carrierCruise liner
Decision Guide: Choose the YMV‑TT‑800 when a vessel needs high thrust for precise low‑speed maneuvering, especially on ships larger than 30 000 gt that can accommodate a 1.14 m tunnel and have sufficient power generation capacity. Avoid it on smaller vessels with limited hull space or where weight and installation complexity outweigh the maneuverability benefit.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
YMV-TT-1000 bow
unverified
· 1000.0 kW
· high‑power tunnel thruster
Power (kW)
1000
Thrust (kN)
120.0
Diameter (mm)
1300
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (120 kN) suitable for vessels >200 m LOA
- Large 1300 mm duct provides efficient water flow and reduced cavitation
- Integrated control interface compatible with most DP systems
- Robust construction rated for continuous operation in harsh sea conditions
Weaknesses
- Significant hull penetration required, limiting installation on smaller ships
- High power demand (1 MW) increases fuel consumption and generator sizing
- Large duct occupies considerable bow space, affecting cargo hatch layout
- Maintenance access can be difficult due to size of the tunnel
Typical Vessels:
Container shipCruise linerLNG carrierOffshore supply vesselFPSO
Decision Guide: Choose if: you need >100 kN bow thrust for precise docking or DP assistance on large vessels and have sufficient hull space and power generation capacity. Avoid if: the ship’s design limits bow duct installation, power budget is tight, or a smaller thruster would meet maneuverability requirements.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
YMV-TT-1000 stern
unverified
· 1000.0 kW
· High‑power tunnel thruster
Power (kW)
1000
Thrust (kN)
120.0
Diameter (mm)
1300
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust output (≈120 kN) suitable for large vessels
- Relatively compact duct diameter (1300 mm) eases retro‑fit in existing hulls
- Integrated duct geometry reduces cavitation and improves efficiency
- Designed for stern installation, providing effective aft maneuverability
- Compatible with variable frequency drives for fine thrust control
Weaknesses
- High electrical power demand (≈1 MW) requires robust shipboard power system
- Installation may need hull reinforcement due to large thrust loads
- Potentially higher noise and vibration levels compared with smaller thrusters
- Limited suitability for vessels with strict weight or space constraints
- Requires dedicated cooling and ventilation infrastructure
Typical Vessels:
Crude oil tankerProduct tankerBulk carrier (≥30,000 dwt)Container ship (large class)Offshore supply vessel
Decision Guide: Choose if the vessel needs >100 kN of lateral thrust for safe docking, undocking or DP assistance and has sufficient power generation capacity. Avoid if the ship’s electrical system cannot support a 1 MW load, space for a 1300 mm duct is unavailable, or hull strength cannot be upgraded without major work.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
YMV-TT-1200 bow
unverified
· 1200.0 kW
· tunnel thruster
Power (kW)
1200
Thrust (kN)
144.0
Diameter (mm)
1460
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (144 kN) suitable for very large ships and DP operations
- Compact duct diameter (1460 mm) fits within standard bow sections while providing strong flow control
- Direct‑drive motor reduces mechanical losses and simplifies maintenance
- Integrated nozzle design improves thrust efficiency and reduces cavitation risk
- Proven in YMV Marine installations for long‑term reliability
Weaknesses
- Large power demand (1 200 kW) increases vessel electrical load and fuel consumption
- Significant hull penetration required, raising structural integration complexity
- Noise and vibration levels can be higher than low‑power alternatives if not properly isolated
- Effectiveness diminishes in very rough sea states or strong cross‑currents
- Higher initial cost compared with smaller‑capacity thrusters
Typical Vessels:
Container ships (>10,000 gt)Cruise linersLarge tankers and VLCCsOffshore supply vessels (OSVs) with DP requirementsLNG carriers
Decision Guide: Choose the YMV‑TT‑1200 when a vessel needs maximum bow thrust for tight port entries, dynamic positioning, or when operating under heavy wind/current conditions. Avoid it on smaller ships where power and space constraints make a lower‑rated thruster more economical.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
YMV-TT-1200 stern
unverified
· 1200.0 kW
· tunnel thruster
Power (kW)
1200
Thrust (kN)
144.0
Diameter (mm)
1460
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (144 kN) suitable for vessels >30,000 DWT requiring strong lateral force
- 1200 kW motor provides ample power margin for demanding port operations and DP assistance
- Robust tunnel housing protects the propeller from debris and reduces cavitation risk compared with open‑propeller designs
- Integrated control electronics (VFD) allow fine thrust modulation and quick response
- Designed for stern installation, improving overall ship handling when combined with a bow thruster
Weaknesses
- Large tunnel diameter (1460 mm) requires significant hull penetration and structural reinforcement
- High power consumption increases fuel use and may affect overall vessel efficiency
- Installation space at the stern can be limited on vessels with cramped aft arrangements
- Maintenance access is more difficult than for bow thrusters because of its location behind other machinery
- Weight and size add to overall ship weight budget, which may be a concern for lighter vessels
Typical Vessels:
Very Large Crude Carriers (VLCC)Ultra‑Large Container Vessels (ULCV)Panamax & Post‑Panamax Bulk CarriersCruise ShipsOffshore Supply Vessels with DP requirements
Decision Guide: Choose if: you need a high‑thrust stern thruster for large vessels operating in confined ports or requiring dynamic positioning support. Avoid if: the vessel is small to medium size, power budget is limited, or hull geometry cannot accommodate a 1.46 m tunnel without extensive reinforcement.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
YMV-TT-1500 bow
unverified
· 1500.0 kW
· tunnel thruster
Power (kW)
1500
Thrust (kN)
180.0
Diameter (mm)
1700
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High power (1500 kW) and thrust (180 kN) suitable for very large ships
- Large 1.7 m tunnel diameter provides efficient water flow and thrust generation
- Compact integration in the bow reduces external appendages and improves hull hydrodynamics
- Robust YMV Marine construction known for long service intervals
- Direct drive layout simplifies maintenance compared with hydraulic‑driven units
Weaknesses
- Large tunnel size limits installation to vessels with sufficient bow space; not suitable for smaller ships or retrofits with tight hull constraints
- High electrical power demand may require upgraded shipboard generators
- Tunnel thrusters can generate hull vibration and acoustic noise, which may be a concern for passenger‑comfort vessels
- Effectiveness decreases in heavy sea states where lateral thrust is partially offset by wave action
- Installation requires significant hull penetration, increasing dry‑dock time and cost
Typical Vessels:
Very Large Crude Carrier (VLCC)Ultra‑Large Container Ship (ULCS)Capesize Bulk CarrierCruise ShipOffshore Support Vessel (large)
Decision Guide: Choose if: you operate a large vessel (≥150 m LOA) that needs high bow thrust for docking, undocking or DP assistance and has sufficient bow space for a 1.7 m tunnel. Avoid if: the ship is smaller, retrofitting constraints limit hull penetration, or acoustic/vibration limits are critical.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
YMV-TT-1500 stern
unverified
· 1500.0 kW
· tunnel thruster
Power (kW)
1500
Thrust (kN)
180.0
Diameter (mm)
1700
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (180 kN) enables rapid lateral movement.
- Large tunnel diameter reduces cavitation risk at high power levels.
- Integrated 1500 kW motor provides sufficient power for vessels over 30,000 gt.
- Stern location improves docking and berthing control.
Weaknesses
- Requires substantial hull penetration due to the 1.7 m tunnel, increasing installation complexity.
- High power demand (1500 kW) may raise auxiliary generator fuel consumption.
- Size limits applicability on smaller vessels with restricted stern space.
- Potential for increased noise and vibration compared with compact azimuth thrusters.
Typical Vessels:
Aframax tankerPanamax container shipHandymax bulk carrierOffshore supply vessel
Decision Guide: Choose if the vessel needs strong low‑speed maneuverability, has sufficient stern space for a 1.7 m tunnel and can accommodate a 1500 kW auxiliary power source. Avoid if the ship is small, has limited hull volume at the stern, or seeks lower fuel consumption with smaller thrusters.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
YMV-TT-2000 bow
unverified
· 2000.0 kW
· tunnel thruster
Power (kW)
2000
Thrust (kN)
240.0
Diameter (mm)
2100
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (240 kN) enables tight turning circles in confined ports.
- Large 2100 mm tunnel diameter reduces cavitation and improves efficiency at high power levels.
- 2000 kW motor provides ample power for vessels over 150 m LOA requiring strong bow assistance.
- Robust, marine‑grade construction typical of YMV Marine equipment ensures long service life.
Weaknesses
- Significant hull penetration required; installation may involve extensive structural modifications.
- High electrical demand can strain a vessel’s power generation system if not properly sized.
- Physical size and weight (not disclosed) limit suitability for smaller ships or retrofits with limited space.
- Potential for increased noise/vibration if acoustic isolation is not incorporated.
Typical Vessels:
Very Large Crude Carrier (VLCC)Ultra‑Large Container Vessel (ULCV)Panamax / Post‑Panamax bulk carriersCruise shipsOffshore supply vessels
Decision Guide: Choose if the vessel requires high bow thrust for port entry/exit, dynamic positioning or emergency stopping and has sufficient hull space and power generation capacity. Avoid on smaller craft, vessels with limited electrical margin, or where installation depth is constrained.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
YMV-TT-2000 stern
unverified
· 2000.0 kW
· Tunnel thruster
Power (kW)
2000
Thrust (kN)
240.0
Diameter (mm)
2100
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High power rating (2000 kW) gives strong lateral thrust for large vessels
- Large 2100 mm tunnel diameter improves hydraulic efficiency and reduces cavitation risk at design load
- Stern location enhances control during berthing, un‑berthing and dynamic positioning
- YMV Marine’s proven hull‑integrated design offers robust structural support
Weaknesses
- High electrical power demand increases fuel consumption for auxiliary generators
- Large tunnel size limits installation to vessels with sufficient stern space
- Maintenance access can be difficult in confined stern tunnels
- Potential for higher acoustic signature compared with smaller thrusters
Typical Vessels:
Container shipCruise linerOffshore supply vesselLNG carrierBulk carrier
Decision Guide: Choose if the vessel requires >200 kN of thrust, has adequate stern space for a 2.1 m tunnel, and needs reliable low‑speed manoeuvring or DP assistance. Avoid if the ship is small, power budget is limited, or an azimuth thruster offers better all‑directional control.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
YMV-TT-2500 bow
unverified
· 2500.0 kW
· tunnel bow thruster
Power (kW)
2500
Thrust (kN)
300.0
Diameter (mm)
2500
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (≈300 kN) suitable for mega‑size ships
- Large duct diameter reduces cavitation risk at high power
- Robust tunnel construction offers good protection against debris and hull fouling
- Direct integration with ship’s control system enables precise low‑speed handling
Weaknesses
- Physical size (2.5 m diameter) limits installation to vessels with ample bow space
- High power demand (≈2.5 MW) increases electrical load and fuel consumption for auxiliary generators
- Installation and maintenance require dry‑dock periods due to tunnel location
- Single large unit provides less redundancy than multiple smaller thrusters
Typical Vessels:
VLCC / Suezmax tankersUltra‑large container vessels (ULCV)Large LNG carriersCruise ships over 200 m LOA
Decision Guide: Choose if the vessel needs maximum bow thrust for port entry/exit, dynamic positioning or emergency stopping of very large ships and has sufficient hull space for a 2.5 m tunnel. Avoid if the ship is size‑restricted, power budget is limited, or redundancy through multiple smaller thrusters is preferred.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
YMV-TT-2500 stern
unverified
· 2500.0 kW
· Tunnel thruster
Power (kW)
2500
Thrust (kN)
300.0
Diameter (mm)
2500
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high power (2 500 kW) and thrust (300 kN) suitable for mega‑size ships
- Robust tunnel construction reduces cavitation and wear
- Stern placement improves astern handling and docking precision
- Relatively simple mechanical layout eases routine maintenance
Weaknesses
- Large 2.5 m tunnel diameter demands significant hull penetration and structural reinforcement
- High electrical power demand increases onboard energy consumption
- Installation is complex and may require dry‑dock time
- Potential for increased noise and vibration compared with smaller units
Typical Vessels:
VLCC / ULCC crude carriersLarge LNG carriersUltra‑large container ships (10 000+ TEU)Very large bulk carriers (>200 kDWT)Offshore support vessels with high maneuverability needs
Decision Guide: Choose if the vessel requires very high stern thrust for safe docking, dynamic positioning or emergency astern maneuvers and can accommodate a 2.5 m tunnel opening. Avoid if the ship is smaller, has limited hull space, or budget constraints make a lower‑power thruster more appropriate.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
YMV-TT-3000 bow
unverified
· 3000.0 kW
· Tunnel bow thruster
Power (kW)
3000
Thrust (kN)
360.0
Diameter (mm)
2900
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (360 kN) suitable for mega‑vessels and tight berths
- Large tunnel diameter reduces cavitation and improves efficiency at high power levels
- Robust construction typical of YMV Marine designs, offering long service life
- Integrated control interface compatible with modern ship bridge systems
Weaknesses
- High electrical power demand (3 MW) may require substantial generator capacity
- Large hull penetration increases installation complexity and structural reinforcement needs
- Physical size limits use on vessels with restricted bow space or shallow drafts
- Higher initial cost compared with smaller, lower‑power thrusters
Typical Vessels:
Cruise shipLNG carrierOffshore supply vesselLarge container shipBulk carrier (>30 000 GT)
Decision Guide: Choose if: the vessel exceeds ~30,000 GT, operates in confined ports or requires rapid bow‑side thrust for dynamic positioning. Avoid if: power generation is limited, hull space is constrained, or the vessel’s maneuvering needs are modest.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
YMV-TT-3000 stern
unverified
· 3000.0 kW
· Tunnel thruster
Power (kW)
3000
Thrust (kN)
360.0
Diameter (mm)
2900
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (360 kN) relative to its diameter, enabling strong stern pulling/pushing forces.
- Robust tunnel construction designed for continuous 3 MW operation.
- Integrated cooling system to manage thermal load at high power levels.
- Low vibration and noise due to balanced rotor design, beneficial for crew comfort.
- Standardized 2.9‑m tunnel diameter fits many new‑build hull forms.
Weaknesses
- Significant electrical power demand (3 MW) increases ship energy consumption.
- Large hull penetration required; structural reinforcement adds installation cost.
- Limited effectiveness in very shallow water where draft exceeds tunnel clearance.
- Higher initial purchase and installation price compared with smaller thrusters.
- Maintenance access can be constrained by the size of the tunnel housing.
Typical Vessels:
Container shipBulk carrierCruise linerLNG carrierOffshore support vessel
Decision Guide: Choose if: the vessel requires high stern thrust for tug‑less berthing, dynamic positioning or emergency stop on ships >80,000 DWT with sufficient power generation capacity. Avoid if: power budget is limited, hull space cannot accommodate a ~3 m tunnel, or operating primarily in very shallow ports where tunnel clearance is restrictive.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
YMV-TT-3500 bow
unverified
· 3500.0 kW
· high‑power tunnel thruster
Power (kW)
3500
Thrust (kN)
420.0
Diameter (mm)
3300
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (420 kN) suitable for vessels >150 kt deadweight
- Robust tunnel design with minimal external moving parts, reducing maintenance
- Large propeller diameter (3.3 m) provides efficient low‑speed thrust generation
- Bow location improves maneuverability during docking and DP operations
Weaknesses
- Large physical envelope limits installation on vessels with restricted bow space
- High power rating (3 500 kW) leads to significant electrical load and fuel consumption
- Potential for cavitation at maximum thrust if not matched with proper hull design
- Installation and integration costs are higher than smaller thruster options
Typical Vessels:
Very Large Crude Carrier (VLCC)LNG carrierUltra‑large container shipLarge bulk carrierOffshore supply vessel with DP requirements
Decision Guide: Choose if the vessel requires >400 kN of bow thrust for safe docking, dynamic positioning or maneuvering in confined ports and has sufficient electrical capacity. Avoid on smaller ships where space, power budget or cost constraints make a lower‑power thruster more appropriate.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
YMV-TT-3500 stern
unverified
· 3500.0 kW
· tunnel thruster
Power (kW)
3500
Thrust (kN)
420.0
Diameter (mm)
3300
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Provides very high thrust (420 kN) suitable for vessels over 150 000 gt.
- Compact tunnel design fits within limited hull space while delivering 3500 kW power.
- Modular drive options (hydraulic or electric) allow flexible installation and integration with ship control systems.
- YMV Marine construction uses corrosion‑resistant stainless steel for the duct, extending service life in harsh marine environments.
Weaknesses
- High power rating results in significant fuel/energy consumption during operation.
- Large 3.3 m diameter may restrict retrofitting on vessels with narrow hull sections or limited beam.
- Maintenance of large bearing and seal assemblies can be costly and require specialized tools.
- YMV's global service network is smaller than that of major thruster manufacturers, potentially affecting spare‑part availability.
Typical Vessels:
Very Large Crude CarrierUltra Large Container VesselLNG CarrierBulk Carrier (>150 000 gt)
Decision Guide: Choose if: you need a high‑thrust stern thruster for vessels over 150 000 gt where hull space allows a 3.3 m tunnel and you value YMV’s modular drive options. Avoid if: the vessel has limited beam or draft that cannot accommodate the duct, or if you require an extensive worldwide after‑sales network.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
YMV-TT-4000 bow
unverified
· 4000.0 kW
· tunnel thruster
Power (kW)
4000
Thrust (kN)
480.0
Diameter (mm)
3700
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (480 kN) suitable for VLCCs, ULCS and other mega‑vessels
- Robust tunnel construction that tolerates harsh marine environments
- Integrated with standard DP control interfaces for easy dynamic positioning integration
- Large 3.7 m duct diameter provides efficient water flow and reduced cavitation at design load
Weaknesses
- Large duct size limits installation to vessels with sufficient bow space
- High power demand (4 MW) increases fuel consumption of auxiliary generators
- Maintenance of large‑diameter bearings and seals can be labour‑intensive
- Spare‑part availability may be limited outside YMV’s dealer network
Typical Vessels:
Very Large Crude Carrier (VLCC)Ultra Large Container Ship (ULCS)Cruise shipOffshore supply vesselLNG carrier
Decision Guide: Choose if the vessel requires >400 kN of bow thrust for safe port entry, dynamic positioning or tight‑berth operations and has sufficient hull space for a 3.7 m tunnel. Avoid on smaller ships where lower‑power thrusters are more economical or when installation space is constrained.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
YMV-TT-4000 stern
unverified
· 4000.0 kW
· high-power tunnel thruster
Power (kW)
4000
Thrust (kN)
480.0
Diameter (mm)
3700
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (480 kN) suitable for the largest merchant ships and offshore platforms
- Large 3700 mm duct provides efficient water flow with reduced cavitation risk
- Integrated stern location improves turning moment for vessels with limited bow space
- 4000 kW motor matches modern diesel‑electric or hybrid power plants
- Standardized tunnel geometry eases installation on new builds and retrofits
Weaknesses
- High electrical power demand (4 MW) may require dedicated generators or UPS capacity
- Large hull penetration demands reinforced structural design and careful sealing
- Installation and maintenance access can be limited in confined stern spaces
- Potential for increased vibration and noise transmission to crew areas
- Higher initial cost compared with lower‑power thrusters
Typical Vessels:
Very Large Crude Carriers (VLCC)Ultra‑Large Container Vessels (ULCV)LNG carriersCruise shipsOffshore supply vessels
Decision Guide: Choose if the vessel requires >400 kN of lateral thrust for tight port manoeuvring, has sufficient onboard power generation, and can accommodate a large stern duct. Avoid if power budget is limited, hull strength cannot support a 3.7 m tunnel, or the operational profile does not demand extreme maneuverability.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
YMV-TT-4500 bow
unverified
· 4500.0 kW
· tunnel thruster
Power (kW)
4500
Thrust (kN)
540.0
Diameter (mm)
4100
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (540 kN) suitable for dynamic positioning and rapid berthing maneuvers.
- Large 4.1 m tunnel diameter promotes efficient water flow and reduces cavitation risk.
- 4.5 MW power rating provides fast response for emergency or precision handling.
- Bow‑mounting improves turning radius and control in confined ports.
Weaknesses
- High electrical power demand requires substantial shipboard generation capacity.
- Physical size of the tunnel (4.1 m diameter) consumes significant hull space, limiting fit on smaller vessels.
- Installation within the hull is complex and may increase construction cost and downtime for maintenance.
- Without dedicated debris protection, tunnel thrusters can be vulnerable to fouling from floating objects.
Typical Vessels:
Container ShipBulk CarrierCruise ShipLNG CarrierOffshore Supply Vessel
Decision Guide: Choose if the vessel requires high lateral thrust for dynamic positioning, tight‑berth maneuvering, or operates in offshore environments where rapid side force is critical. Avoid if the ship has limited electrical generation capacity, restricted hull space, or only modest maneuverability needs.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
YMV-TT-4500 stern
unverified
· 4500.0 kW
· Tunnel thruster
Power (kW)
4500
Thrust (kN)
540.0
Diameter (mm)
4100
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust output (540 kN) suitable for mega‑vessels
- Large 4.1 m tunnel diameter provides efficient water flow and reduced cavitation
- High power rating (4500 kW) enables rapid low‑speed positioning
- Robust construction typical of YMV Marine equipment for harsh sea conditions
Weaknesses
- Large physical size limits installation to vessels with sufficient stern space
- High electrical power demand may require upgraded shipboard power systems
- Maintenance access can be more complex due to the large tunnel dimensions
- Potentially higher initial cost compared with smaller thruster units
Decision Guide: Choose if the vessel needs >500 kN of stern thrust for berthing or maneuvering in confined ports, especially on ultra‑large container ships, LNG carriers, cruise liners or offshore support vessels. Avoid if space is limited, power supply cannot accommodate 4500 kW, or a lower thrust rating would suffice.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
YMV-TT-5000 bow
unverified
· 5000.0 kW
· high-power tunnel thruster
Power (kW)
5000
Thrust (kN)
600.0
Diameter (mm)
4500
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust output (600 kN) suitable for mega‑vessels
- Large 4.5 m duct diameter promotes efficient water flow and reduces cavitation risk
- Integrated 5 MW electric drive provides rapid response and fine speed control
- Tunnel installation protects the unit from external impact and fouling
- Optimised for bow placement, giving a strong turning moment for port maneuvers
Weaknesses
- Physical size (4.5 m diameter) restricts retrofit on smaller hulls
- High electrical power demand requires substantial shipboard power infrastructure
- Installation is complex due to large duct and foundation requirements
- Potential for increased noise and vibration at full‑thrust operation
- Limited global service network if YMV Marine has few authorised yards
Typical Vessels:
Ultra Large Container VesselVery Large Crude CarrierLNG CarrierCruise ShipOffshore Support Vessel
Decision Guide: Choose if: you need a bow thruster capable of delivering >600 kN thrust for vessels over 200 m LOA, operating in tight ports where rapid lateral movement is critical, and the ship has sufficient electrical generation capacity. Avoid if: vessel size or hull geometry cannot accommodate a 4.5 m duct, power plant cannot support a 5 MW drive, or you prefer a more compact external pod thruster for retrofit projects.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
YMV-TT-5000 stern
unverified
· 5000.0 kW
· tunnel thruster
Power (kW)
5000
Thrust (kN)
600.0
Diameter (mm)
4500
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (≈600 kN) suitable for mega‑size ships and tight port manoeuvring
- Large 4.5 m duct diameter helps reduce cavitation and improve efficiency at high power levels
- Robust construction intended for harsh marine environments and continuous operation
Weaknesses
- High electrical demand (≈5 MW) may exceed the power budget of many vessels
- Significant installation space required in the hull due to large diameter and motor size
- Potentially higher capital cost and maintenance effort compared with lower‑power thrusters
Typical Vessels:
VLCC (Very Large Crude Carrier)ULCV (Ultra‑Large Container Vessel)LNG carrierOffshore supply vessel
Decision Guide: Choose if the ship needs exceptional low‑speed thrust for safe berthing in confined ports or dynamic positioning of very large vessels. Avoid if power availability, hull space, or budget constraints make a smaller thruster more appropriate.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
Kawasaki
20
KBT-150
1500 kW
· 1500.0 kW
· Seawater
· Fixed-pitch propeller tunnel thruster
Common Failures & Inspection Points
- Hydraulic leakage or low oil level causes reduced pressure, slow movement or low-level alarms
- Pump, motor or drive faults cause loss of one power unit, reduced thrust or failure to move the rudder
- Control, feedback or position-sensor faults cause hunting, incorrect indication or failure to reach the commanded position
- Bearing, seal or mechanical wear causes vibration, leakage, backlash or abnormal noise
- Air ingress, contamination or cooling faults cause unstable hydraulic or drive performance and protective trips
Service: Inspect power units, oil or lubrication condition, actuators or thruster drive, seals, feedback transmitters, controls and structural connections. Test main, standby and emergency arrangements according to the approved vessel and class procedure. Check leakage, vibration and response throughout the operating range. Refer to the manufacturer documentation for the exact figure for pressure, alignment and wear limits.
Spare Parts: Carry hydraulic filters, seals, hose or pipe repair provisions, motor-control spares, feedback sensors, relays, fuses and critical valve or drive service parts.
Strengths
- Proven Kawasaki mechanical design with robust housing
- Compact tunnel installation suitable for limited hull space
- Good thrust efficiency at moderate RPMs
- Straightforward diesel‑starter drive simplifies integration on vessels without high‑power electric systems
- Established service guidance (e.g., regular blade‑tip inspection for cavitation)
Weaknesses
- Gear wear reported as a common failure mode, requiring periodic gear inspections
- Shaft seal leaks can lead to water ingress if not monitored
- Propeller blade erosion and cavitation damage reduce performance over time
- Electrical starter faults may cause start‑up reliability issues
- Limited thrust compared with larger electric tunnel thrusters for high‑power applications
Typical Vessels:
Offshore supply vesselFerryMedium‑size container shipCruise ship (for bow/stern assistance)Coastal tanker
Decision Guide: Choose if you need a reliable, mechanically driven tunnel thruster on a vessel that already uses diesel power and can accommodate regular gear and seal maintenance. Avoid if the vessel requires very high thrust levels, prefers an all‑electric drive, or operates in conditions where cavitation is a persistent problem.
Use Cases: Steering and harbour manoeuvring on merchant, passenger, offshore and work vessels.
Marine Bow Thruster
500-3000 kW
· 1800.0 kW
· Seawater
· hydraulic tunnel thruster
Power (kW)
1800
Type
Tunnel Thruster
Common Failures & Inspection Points
- Hydraulic leakage or low oil level causes reduced pressure, slow movement or low-level alarms
- Pump, motor or drive faults cause loss of one power unit, reduced thrust or failure to move the rudder
- Control, feedback or position-sensor faults cause hunting, incorrect indication or failure to reach the commanded position
- Bearing, seal or mechanical wear causes vibration, leakage, backlash or abnormal noise
- Air ingress, contamination or cooling faults cause unstable hydraulic or drive performance and protective trips
Service: Inspect power units, oil or lubrication condition, actuators or thruster drive, seals, feedback transmitters, controls and structural connections. Test main, standby and emergency arrangements according to the approved vessel and class procedure. Check leakage, vibration and response throughout the operating range. Refer to the manufacturer documentation for the exact figure for pressure, alignment and wear limits.
Spare Parts: Carry hydraulic filters, seals, hose or pipe repair provisions, motor-control spares, feedback sensors, relays, fuses and critical valve or drive service parts.
Strengths
- Very high power rating (≈1800 kW) suitable for large tankers and bulk carriers
- Proven reliability on Japanese‑built vessels, with extensive service history
- Compact tunnel installation saves deck space compared to external azimuth units
- Robust hydraulic motor design tolerates harsh marine environments
- Straightforward integration with ship’s existing hydraulic power unit (HPU)
Weaknesses
- Requires dedicated HPU and regular hydraulic maintenance; leaks are a known failure mode
- Tunnel grid can suffer wear or damage, leading to reduced efficiency
- Shaft alignment must be monitored closely during installation and service
- Control‑valve malfunctions may affect response time in critical maneuvers
- Heavier and bulkier than comparable electric thrusters, impacting hull design
Typical Vessels:
TankerBulk Carrier
Decision Guide: Choose if the vessel needs high bow thrust for safe berthing of large deadweight ships and already has a hydraulic power system; the Kawasaki unit offers proven performance at a lower upfront cost than electric alternatives. Avoid if you prefer low‑maintenance electric drives, have limited hull space for a tunnel, or operate vessels where precise, rapid thrust modulation is critical.
Use Cases: Steering and harbour manoeuvring on merchant, passenger, offshore and work vessels.
KBE-200 bow
unverified
· 200.0 kW
· tunnel thruster
Power (kW)
200
Thrust (kN)
24.0
Diameter (mm)
650
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (24 kN at 200 kW) for its size
- Compact tunnel diameter (650 mm) fits moderate‑size hulls
- Integrated control electronics from Kawasaki simplify installation
- Proven reliability of Kawasaki marine propulsion brand
- Relatively low acoustic signature, suitable for noise‑sensitive ports
Weaknesses
- Power demand may be high for vessels with limited electrical generation capacity
- Hull penetration required; installation can be labour‑intensive
- Cavitation risk at maximum thrust in shallow water
- Maintenance of bearings and seals still needed on a regular schedule
- Limited thrust compared to larger 300 kW+ thrusters for very large vessels
Typical Vessels:
Container ship (up to ~30,000 GT)Bulk carrier (up to ~40,000 DWT)Ro‑Ro ferryOffshore supply vesselCruise liner (mid‑size)
Decision Guide: Choose the KBE-200 if you need a reliable, high‑thrust bow thruster for vessels up to medium size where space is limited and low noise is important. Avoid it on very large ships that require >30 kN thrust or when the vessel’s power plant cannot comfortably supply an additional 200 kW.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
KBE-200 stern
unverified
· 200.0 kW
· hydraulic tunnel thruster
Power (kW)
200
Thrust (kN)
24.0
Diameter (mm)
650
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (24 kN from 200 kW)
- Compact 650 mm tunnel diameter fits ships with limited hull space
- Kawasaki’s reputation for durability and low vibration
- Simple hydraulic drive reduces electrical complexity on board
Weaknesses
- Maximum thrust may be insufficient for large vessels (>30 kN required)
- Hull penetration of a 650 mm tunnel can be structurally demanding
- Hydraulic system adds maintenance requirements (oil changes, seal checks)
- Potential cavitation at high load in shallow water
Typical Vessels:
Handymax bulk carrierFeeder container shipOffshore supply vesselCruise‑ship tenderMedium‑size ferry
Decision Guide: Choose if: you need a reliable stern thruster for vessels up to ~20 000 DWT with limited hull space and prefer hydraulic drive simplicity. Avoid if: the vessel requires thrust above 30 kN, operates in very shallow water where cavitation is critical, or you want an all‑electric solution.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
KBE-300 bow
unverified
· 300.0 kW
· tunnel thruster
Power (kW)
300
Thrust (kN)
36.0
Diameter (mm)
725
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (36 kN at 300 kW) for rapid lateral movement
- Compact tunnel diameter (725 mm) relative to its thrust output, easing hull integration
- Kawasaki’s reputation for robust mechanical design and long service intervals
- Low vibration and noise levels typical of well‑balanced tunnel units
- Standardized control interface compatible with most ship bridge systems
Weaknesses
- 300 kW power demand requires substantial electrical supply and cooling capacity
- Tunnel size may be restrictive on vessels with limited hull space or shallow drafts
- Higher upfront cost compared with lower‑rated generic thrusters
- Spare‑part logistics can be slower in regions without a Kawasaki service network
- Installation often needs structural reinforcement of the bow section
Typical Vessels:
Container ships (≈150 m LOA)Cruise linersOffshore supply vesselsLNG carriersLarge ferries
Decision Guide: Choose the KBE-300 when a vessel needs strong bow thrust for tight‑port docking, dynamic positioning support, or emergency maneuvering and has sufficient electrical capacity and hull space for a 725 mm tunnel. Avoid it on smaller ships where lower power thrusters suffice or where installation constraints make the tunnel diameter problematic.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
KBE-300 stern
unverified
· 300.0 kW
· tunnel thruster
Power (kW)
300
Thrust (kN)
36.0
Diameter (mm)
725
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (36 kN) relative to power consumption (300 kW)
- Robust tunnel housing reduces cavitation and improves efficiency
- Compact diameter (725 mm) fits within standard hull tunnels for retro‑fit
- Integrated control interface compatible with most ship bridge systems
- Proven reliability from Kawasaki’s marine propulsion heritage
Weaknesses
- Large tunnel size may limit installation on vessels with narrow hull sections
- Higher power rating increases fuel consumption when used continuously
- Maintenance access can be restricted by the tunnel geometry
- Potential for increased noise/vibration at full power compared with azimuth thrusters
- Limited availability of spare parts in remote ports relative to more common brands
Typical Vessels:
Container shipCrude oil tankerLNG carrierCruise linerOffshore supply vessel
Decision Guide: Choose if: you need a high‑thrust stern thruster for large vessels requiring strong low‑speed maneuverability, dynamic positioning or berthing assistance, and the hull can accommodate a ~0.73 m tunnel. Avoid if: vessel size is small, hull space at the stern is constrained, or lower power/weight solutions are preferred.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
KBE-500 bow
unverified
· 500.0 kW
· tunnel bow thruster
Power (kW)
500
Thrust (kN)
60.0
Diameter (mm)
875
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust‑to‑power ratio (≈60 kN at 500 kW) for rapid lateral movement
- Robust tunnel design tolerates harsh marine environments and reduces vibration
- Integrated control electronics compatible with most ship bridge systems
- Proven reliability from extensive service on container ships and cruise vessels
- Relatively low acoustic signature compared with external propeller thrusters
Weaknesses
- Large tunnel diameter (875 mm) requires significant hull space, limiting installation on smaller ships
- Higher power demand increases fuel consumption when used frequently
- Maintenance of bearing and seal assemblies can be labour‑intensive
- Potential for cavitation at very high thrust settings, especially in shallow water
- Initial procurement cost is higher than lower‑power alternatives
Typical Vessels:
Container ships (10 000–15 000 TEU)Cruise linersOffshore supply vesselsLNG carriersRo‑Ro ferries
Decision Guide: Choose if: the vessel requires strong low‑speed lateral thrust for port manoeuvring or DP assistance and has sufficient bow space for an ~0.9 m tunnel; you need a proven, high‑power unit with integrated bridge control. Avoid if: the ship is small or draft‑restricted where the large tunnel cannot be accommodated, budget constraints dominate, or low power/low thrust solutions are sufficient.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
KBE-500 stern
unverified
· 500.0 kW
· tunnel thruster
Power (kW)
500
Thrust (kN)
60.0
Diameter (mm)
875
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (≈60 kN) relative to power rating, enabling effective stern manoeuvring.
- Compact tunnel diameter (875 mm) fits into moderate hull spaces while providing adequate flow.
- Kawasaki’s reputation for robust marine propulsion equipment translates to long service intervals and reliability.
- Integrated motor‑pump design reduces external moving parts, lowering maintenance needs.
- Suitable for both manual docking assistance and DP‑assisted operations.
Weaknesses
- Large tunnel cross‑section can intrude into cargo or machinery space on smaller vessels.
- Power consumption (500 kW) may be high for vessels seeking lower fuel use during low‑speed ops.
- Potential cavitation noise at higher thrust settings, requiring acoustic mitigation in passenger ships.
- Weight and mounting requirements are significant; detailed structural analysis is needed before installation.
- Limited availability of spare parts outside Kawasaki’s dealer network in some regions.
Typical Vessels:
Container shipBulk carrierProduct tankerCruise liner (mid‑size)Offshore supply vessel
Decision Guide: Choose if: you need a reliable 60 kN stern thruster for vessels of 30–80 kt service speed, have sufficient hull volume for an 875 mm tunnel, and value Kawasaki’s proven durability. Avoid if: vessel weight or space constraints are critical, you require higher thrust per kW, or you operate in noise‑sensitive environments without mitigation measures.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
KBE-750 bow
unverified
· 750.0 kW
· electric tunnel thruster
Power (kW)
750
Thrust (kN)
90.0
Diameter (mm)
1062
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust-to-power ratio (≈90 kN at 750 kW) suitable for large ships
- Compact duct diameter (≈1.06 m) fits within tight bow spaces
- Low vibration and noise thanks to water‑cooled permanent‑magnet motor
- Integrated control system with feedback for precise thrust vectoring
- Proven reliability on cruise ships, container vessels and LNG carriers
Weaknesses
- Requires substantial electrical supply infrastructure (high‑capacity generators)
- Installation demands precise alignment of the tunnel duct in the hull
- Higher upfront cost compared to smaller or hydraulic thrusters
- Limited thrust increase potential without major redesign (fixed impeller size)
- Maintenance access can be challenging due to bow location
Typical Vessels:
Cruise shipContainer vesselLNG carrierBulk carrier (>30 000 gt)Ferry / Ro‑Ro
Certifications:
IMO Type ApprovalDNV GL Class approval
Decision Guide: Choose if: you need a high‑thrust bow thruster for vessels >30,000 gt where space is limited and electric power is available; you value low noise/vibration and integrated control for precise maneuvering or DP support. Avoid if: the ship’s electrical system cannot accommodate 750 kW per thruster, budget constraints dominate, or an azimuth/azipod solution is required for thrust in multiple directions.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
KBE-750 stern
unverified
· 750.0 kW
· tunnel thruster
Power (kW)
750
Thrust (kN)
90.0
Diameter (mm)
1062
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust-to-power ratio (≈90 kN at 750 kW) for effective low‑speed manoeuvring
- Compact duct diameter (1062 mm) fits vessels with limited hull space
- Kawasaki’s reputation for robust, low‑maintenance marine equipment
- Integrated variable frequency drive enables precise thrust control and DP compatibility
- Proven performance on a range of large commercial vessels
Weaknesses
- Potential cavitation and noise at high load conditions
- Requires significant hull penetration and structural reinforcement during installation
- Limited to lateral thrust; cannot provide full 360° thrust vectoring like azimuth thrusters
- Higher power consumption compared with smaller or auxiliary thruster options
- May generate vibration that needs mitigation in passenger‑focused vessels
Typical Vessels:
Container shipCrude oil tankerProduct tankerLNG carrierCruise shipOffshore supply vessel
Decision Guide: Choose if: you need a high‑thrust stern thruster for large vessels, have sufficient hull space for a ~1.06 m duct, and require reliable low‑speed manoeuvring or DP support. Avoid if: the vessel demands full 360° thrust vectoring, operates in extremely tight ports where azimuth thrusters are preferred, or weight/space constraints preclude a tunnel installation.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
KBE-1000 bow
unverified
· 1000.0 kW
· high‑power tunnel thruster
Power (kW)
1000
Thrust (kN)
120.0
Diameter (mm)
1250
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (≈120 kN) suitable for ultra‑large ships and DP operations
- Compact tunnel layout saves deck space compared with azimuth units of similar power
- Kawasaki’s proven marine reputation offers long‑term reliability and low maintenance
- Integrated water‑cooling system handles the 1 MW rating efficiently
Weaknesses
- Large diameter (1.25 m) limits installation in shallow drafts or small hulls
- High power consumption increases fuel use for auxiliary generators
- Installation requires significant structural reinforcement and precise alignment
- Potential cavitation noise at full‑load conditions may affect crew comfort
Typical Vessels:
Ultra‑large container shipsCruise linersOffshore supply vessels (OSV)LNG carriersLarge Ro‑Ro ferries
Decision Guide: Choose if: you need >100 kN bow thrust for a vessel over 150 m LOA, require proven reliability and compact tunnel geometry, or operate under DP requirements. Avoid if: the ship has limited draft, budget constraints limit auxiliary power, or space for a 1.25 m tunnel is unavailable.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
KBE-1000 stern
unverified
· 1000.0 kW
· integrated electric tunnel thruster
Power (kW)
1000
Thrust (kN)
120.0
Diameter (mm)
1250
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (120 kN) suitable for large vessels
- Compact footprint with the motor housed inside the tunnel eliminates external gearboxes
- Direct‑drive design reduces vibration and noise levels
- Robust construction suited to harsh marine environments
Weaknesses
- Large duct diameter (1.25 m) requires significant hull penetration and structural reinforcement
- High electrical power demand (≈1000 kW) may strain shipboard power systems
- Maintenance access can be limited due to the integrated motor layout
- Initial procurement cost is typically higher than conventional shaft‑driven thrusters
Typical Vessels:
Container shipsCrude oil tankersLNG carriersCruise linersOffshore supply vessels
Decision Guide: Choose if: you need a high‑thrust stern thruster for a vessel >30 000 gt, have sufficient hull space for a 1.25 m tunnel, and can provide ~1 MW of electrical power. Avoid if: the ship is small to medium size, power budget is limited, or hull modifications are undesirable.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
KBE-1500 bow
unverified
· 1500.0 kW
· tunnel thruster
Power (kW)
1500
Thrust (kN)
180.0
Diameter (mm)
1625
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (≈180 kN) suitable for large ships and DP assistance
- Robust tunnel construction with corrosion‑resistant lining for long service life
- Integrated cooling system allows continuous operation at full power
- Compact footprint relative to thrust output, fitting within standard bow tunnels of 1.6 m diameter
- Kawasaki’s reputation for reliability and global support network
Weaknesses
- Large tunnel diameter (≈1.62 m) may limit installation on vessels with restricted hull space
- High power demand (1.5 MW) increases fuel consumption when used extensively
- Installation requires precise alignment and substantial structural reinforcement
- Initial cost is higher than lower‑power alternatives
- Noise and vibration levels need mitigation in passenger‑focused ships
Typical Vessels:
Cruise shipLNG carrierLarge container vesselBulk carrier (>150 kt)Offshore support vessel
Decision Guide: Choose if the vessel needs strong low‑speed maneuverability, has sufficient bow space for a ~1.6 m tunnel, and can accommodate the high power draw; avoid on smaller ships or where budget and hull‑space constraints dominate.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
KBE-1500 stern
unverified
· 1500.0 kW
· Tunnel thruster
Power (kW)
1500
Thrust (kN)
180.0
Diameter (mm)
1625
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high power (1 500 kW) and thrust (180 kN) gives strong manoeuvre capability even in adverse conditions
- Large 1 625 mm duct diameter improves hydraulic efficiency and reduces flow losses
- Kawasaki’s reputation for robust marine‑grade components translates to long service intervals
- Modular construction allows relatively straightforward installation and on‑site replacement of the motor unit
- Designed for stern mounting, providing effective thrust vector for vessels with limited bow space
Weaknesses
- Physical size and required hull penetration make it unsuitable for small or retrofit‑constrained ships
- High electrical demand (1 500 kW) necessitates a capable shipboard power system and may increase fuel consumption when used frequently
- At maximum thrust the large propeller can be prone to cavitation if not matched with proper duct design
- Initial capital cost is higher than lower‑power thrusters, which may affect budget‑constrained projects
- Spare‑part logistics rely on Kawasaki’s global network; lead times can be longer in remote regions
Typical Vessels:
Container ships (>10 000 TEU)Crude oil and product tankersBulk carriers (Handymax and larger)Cruise linersOffshore supply vessels with dynamic positioning
Decision Guide: Choose if: the vessel exceeds 20 000 dwt, requires strong stern thrust for tight berthing or DP operations, and has sufficient onboard power capacity. Avoid if: space constraints prevent a large tunnel installation, the ship’s power plant cannot support 1.5 MW thruster load, or budget limits preclude high‑cost equipment.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
KBE-2000 bow
unverified
· 2000.0 kW
· tunnel bow thruster
Power (kW)
2000
Thrust (kN)
240.0
Diameter (mm)
2000
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high static thrust (240 kN) suitable for large ships and tight port operations
- Compact tunnel layout minimizes deck space compared with external azimuth units
- Kawasaki’s proven reliability and long service life in harsh marine environments
- Integrated water‑cooling system reduces overheating during prolonged use
- Relatively low acoustic signature versus open‑propeller thrusters
Weaknesses
- Large tunnel diameter (2 m) requires significant hull penetration and structural reinforcement
- Higher installation and retro‑fit cost than smaller conventional bow thrusters
- Maintenance access can be limited because the unit is housed within the hull tunnel
- Power demand (2 MW) increases fuel consumption when used frequently
- Less flexible for dynamic positioning compared with azimuth or pod‑type thrusters
Typical Vessels:
Container ships (>10,000 gt)Cruise linersLarge tankers and product carriersLNG/LPG carriersOffshore support vessels (OSVs) with high maneuverability needs
Decision Guide: Choose if: you need very high bow thrust for a large vessel, have sufficient hull space for a 2 m tunnel, and value Kawasaki’s reputation for durability. Avoid if: the ship is smaller, budget‑constrained, or requires the omnidirectional thrust of an azimuth pod for dynamic positioning.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
KBE-2000 stern
unverified
· 2000.0 kW
· 2000 kW tunnel thruster
Power (kW)
2000
Thrust (kN)
240.0
Diameter (mm)
2000
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (≈240 kN) suitable for large ships and DP assistance
- Robust Kawasaki engineering with proven reliability in harsh marine environments
- Compact tunnel layout minimizes above‑deck space requirements
- Integrated cooling system handles the 2000 kW power rating efficiently
Weaknesses
- Large hull opening (≈2 m diameter) requires extensive structural reinforcement
- High electrical power demand may necessitate dedicated generators or converters
- Installation and commissioning costs are significant for retrofit projects
Typical Vessels:
LNG carrierCruise shipOffshore supply vesselLarge container shipBulk carrier (≥150 kt)
Decision Guide: Choose if: you need a high‑thrust stern thruster for vessels >150 kt, require DP or tight‑port maneuverability, and have sufficient power generation capacity. Avoid if: the vessel size is small, hull space for a 2 m tunnel is limited, or electrical supply cannot support 2000 kW.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
KBE-2500 bow
unverified
· 2500.0 kW
· tunnel thruster
Power (kW)
2500
Thrust (kN)
300.0
Diameter (mm)
2375
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (≈300 kN) suitable for mega‑size ships and DP assistance
- Large 2.375 m duct diameter reduces cavitation and improves efficiency
- Robust steel housing and sealed bearing system designed for harsh marine environments
- Integrated control electronics compatible with most ship bridge systems
- Proven track record in ultra‑large tankers and container vessels
Weaknesses
- High installed power (≈2 500 kW) leads to significant fuel consumption when used frequently
- Large hull penetration requires extensive structural reinforcement and space
- Maintenance of the large bearing and seal assemblies can be costly and time‑intensive
- Noise and vibration levels are higher than smaller thrusters, may need additional mitigation
- Capital cost is relatively high compared with lower‑power alternatives
Typical Vessels:
Ultra‑large crude carriers (ULCC)Very large crude carriers (VLCC)Mega container ships (>15 000 TEU)Large cruise linersOffshore support vessels with dynamic positioning
Decision Guide: Choose if: you need very high bow thrust for a vessel >80 000 GT, operate in confined ports or require DP assistance; you have sufficient hull space and budget for installation and maintenance. Avoid if: the ship is small to medium size, hull penetration area is limited, or operating cost sensitivity outweighs maneuverability benefits.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
KBE-2500 stern
unverified
· 2500.0 kW
· hydraulic‑driven tunnel thruster
Power (kW)
2500
Thrust (kN)
300.0
Diameter (mm)
2375
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (≈300 kN) suitable for vessels >150 m LOA
- Compact tunnel diameter (2.375 m) fits into standard stern tunnels without excessive hull penetration
- Integrated variable‑frequency drive allows fine thrust control and energy efficiency
- Proven Kawasaki reliability record in marine propulsion systems
Weaknesses
- Large power rating demands high‑capacity shipboard electrical supply and cooling
- Installation requires substantial structural reinforcement of the stern tunnel
- Spare parts and service support are regionally concentrated (Japan/Korea), potentially increasing lead times for remote operators
- Noise and vibration levels can be higher than newer ducted‑propeller designs if not properly isolated
Typical Vessels:
Container shipBulk carrierOil tankerRo‑Ro vesselCruise ship (large)
Decision Guide: Choose if: you need a high‑thrust stern thruster for vessels >150 m with existing high‑capacity electrical infrastructure and can accommodate the tunnel size. Avoid if: your vessel has limited power generation, tight hull space constraints, or you require a low‑noise solution without extensive vibration mitigation.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
KBE-3000 bow
unverified
· 3000.0 kW
· electric tunnel thruster
Power (kW)
3000
Thrust (kN)
360.0
Diameter (mm)
2750
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- 3000 kW motor provides high thrust (up to 360 kN) for precise docking and DP operations.
- Large 2.75 m tunnel diameter reduces cavitation risk and improves efficiency at high loads.
- Integrated cooling system typical of Kawasaki designs enhances reliability in continuous operation.
- Modular construction allows relatively straightforward installation on new builds or major retrofits.
Weaknesses
- Physical size and weight require substantial hull reinforcement and may limit use on smaller vessels.
- High power demand increases vessel electrical load and may necessitate upgraded generators.
- Maintenance of large bearings and seals can be more costly compared with smaller thrusters.
Typical Vessels:
LNG carrierCruise shipVery Large Container Ship (VLCS)Ultra‑large crude oil tankerOffshore supply vessel
Decision Guide: Choose if the vessel exceeds 200 m LOA and requires >300 kN bow thrust for tight‑port maneuvering, dynamic positioning or emergency response. Avoid if hull space is limited, the ship’s power plant cannot support an additional 3 MW load, or a lower‑thrust thruster would meet operational needs.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
KBE-3000 stern
unverified
· 3000.0 kW
· water‑lubricated tunnel thruster
Power (kW)
3000
Thrust (kN)
360.0
Diameter (mm)
2750
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (≈360 kN) suitable for large ships and DP operations
- Robust water‑lubricated bearing system reduces wear and maintenance intervals
- Integrated control electronics compatible with most ship bridge systems
- Large duct diameter improves efficiency at low vessel speeds
- Proven Kawasaki manufacturing quality and service network
Weaknesses
- Large tunnel size (2.75 m) limits installation locations and may affect hull strength
- High power demand (≈3 MW) increases fuel consumption and requires substantial generator capacity
- Potential for cavitation in very shallow water or at high propeller speeds
- Heavier overall unit adds to vessel weight budget
- Installation and commissioning costs are higher than smaller thrusters
Typical Vessels:
LNG carrierCruise shipLarge container vesselOffshore supply vesselFPSO / FSRU
Decision Guide: Choose if: the vessel requires strong stern thrust for dynamic positioning, tight‑berth maneuvering or emergency stopping and has sufficient power generation capacity. Avoid if: the ship is smaller, power budget is limited, hull geometry cannot accommodate a 2.75 m tunnel, or lower thrust solutions meet the operational needs.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
IHC/MSI
16
CT-100 bow
unverified
· 100.0 kW
· electric tunnel thruster
Power (kW)
100
Thrust (kN)
12.0
Diameter (mm)
580
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Provides a high thrust‑to‑power ratio (12 kN at 100 kW) suitable for vessels up to ~30 000 DWT.
- Compact 580 mm duct diameter fits within moderate hull forms without excessive structural reinforcement.
- Direct‑drive motor reduces vibration and maintenance intervals compared with gear‑driven units.
- Stainless‑steel ducting offers good corrosion resistance in seawater environments.
Weaknesses
- Maximum thrust may be insufficient for larger tankers or cruise ships that require >20 kN bow thrust.
- Installation requires a relatively large hull opening, which can affect structural integrity if not properly reinforced.
- Power demand of 100 kW can be significant for vessels with limited auxiliary power capacity.
- Noise and cavitation levels are higher than some newer low‑speed propeller‑type thrusters.
Typical Vessels:
Handysize bulk carrierFeeder container shipProduct tanker (up to ~30 000 DWT)Offshore supply vesselCoastal passenger ferry
Decision Guide: Choose if the vessel needs reliable bow‑side maneuvering power of around 12 kN, has sufficient auxiliary power (≈100 kW) and can accommodate a 580 mm tunnel without major hull redesign. Avoid for very large ships requiring higher thrust or when hull space is at a premium.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CT-100 stern
unverified
· 100.0 kW
· tunnel thruster
Power (kW)
100
Thrust (kN)
12.0
Diameter (mm)
580
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (≈12 kN @ 100 kW) for its size
- Compact tunnel diameter (580 mm) fits in limited hull spaces
- Robust, low‑maintenance brushless motor design
- Proven track record on a variety of commercial vessels
- Standard class approvals simplify installation and certification
Weaknesses
- Fixed‑direction thrust; less flexible than azimuth or pod thrusters
- Cavitation risk at high RPMs in shallow water
- Vibration transmitted to hull can require additional damping
- Limited maximum thrust makes it unsuitable for large DP‑required vessels
Typical Vessels:
Offshore supply vesselRo‑Ro ferryContainer feederPassenger ferrySmall bulk carrier (≤10 000 DWT)
Certifications:
DNVABS
Decision Guide: Choose if you need a reliable, cost‑effective stern thruster for vessels up to about 10 000 DWT that require moderate thrust for docking and low‑speed manoeuvring. Avoid if the vessel requires high‑power DP capability, very high thrust (>15 kN), or full 360° thrust vectoring.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CT-200 bow
unverified
· 200.0 kW
· tunnel thruster
Power (kW)
200
Thrust (kN)
24.0
Diameter (mm)
660
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (24 kN from 200 kW) for its size
- Compact 660 mm tunnel fits moderate hull openings
- Robust steel tunnel construction with proven IHC durability
- Integrated control electronics compatible with most bridge systems
- Relatively low acoustic signature compared with azimuth units
Weaknesses
- Maximum thrust (24 kN) may be insufficient for large vessels or high‑wind conditions
- Installation requires a sizable hull cut‑out and reinforcement
- Maintenance of bearings and seals can be labour‑intensive on older designs
- Potential cavitation at high RPMs in shallow water
- Limited to bow installation; not suitable as a stern thruster for larger ships
Typical Vessels:
Offshore Supply Vessel (OSV)Coastal Container FeederRo‑Ro FerryPassenger FerrySmall Bulk Carrier (≤5,000 GT)
Decision Guide: Choose the CT-200 if you need a reliable moderate‑power bow thruster for vessels up to about 5,000 GT that can accommodate a 660 mm tunnel and require good thrust without the cost of larger azimuth units. Avoid it on ships demanding >30 kN thrust, on vessels with limited hull opening space, or where high‑speed dynamic positioning is required.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CT-200 stern
unverified
· 200.0 kW
· tunnel thruster
Power (kW)
200
Thrust (kN)
24.0
Diameter (mm)
660
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (24 kN at 200 kW) for its size class
- Compact 660 mm tunnel fits in medium‑size hulls without excessive structural reinforcement
- Low vibration and noise levels due to optimized impeller geometry
- Standardized control interface compatible with most ship bridge systems
- Proven reliability on offshore support vessels and ferries
Weaknesses
- Maximum thrust of 24 kN may be insufficient for large tankers or high‑power DP applications
- Installation requires precise hull cut‑out; retrofits can be costly
- Cavitation risk increases if operated near full power in shallow water
- Limited to 200 kW electrical supply – not suitable where higher power margins are required
Typical Vessels:
Offshore Supply VesselRo‑Ro FerryCoastal Container ShipSmall Crude Oil Tanker (up to 15,000 dwt)Cruise Ship Tender
Decision Guide: Choose if: you need a reliable medium‑size stern thruster for vessels up to ~20,000 dwt with limited power budget and can accommodate a 660 mm tunnel. Avoid if: the vessel requires thrust above 30 kN, operates in very shallow water where cavitation is critical, or retrofitting space and structural allowances are insufficient.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CT-300 bow
unverified
· 300.0 kW
· hydraulic tunnel thruster
Power (kW)
300
Thrust (kN)
36.0
Diameter (mm)
740
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (36 kN from 300 kW) for effective low‑speed maneuvering
- Compact 740 mm tunnel diameter fits into narrow hull sections
- Integrated hydraulic drive reduces mechanical complexity and eases installation
- Proven reliability on a range of commercial vessels
- Low vibration and noise levels compared with larger open‑propeller thrusters
Weaknesses
- Maximum thrust may be insufficient for very large ships or high‑wind/strong‑current conditions
- Tunnel size still requires significant hull penetration, affecting structural reinforcement needs
- Maintenance access to the internal pump and motor can be limited in tight spaces
- Hydraulic system adds auxiliary power demand and potential leak points
- Limited availability of spare parts in remote ports compared with more common OEMs
Typical Vessels:
Product Tanker (up to ~30 000 dwt)Container FeederHandymax Bulk CarrierOffshore Supply VesselCruise Ship (mid‑size)
Decision Guide: Choose if: you need a medium‑power bow thruster with a compact tunnel for vessels up to ~30 000 dwt, where hull space is at a premium and reliable low‑speed maneuverability is required. Avoid if: the vessel demands thrust well above 40 kN, operates in extreme weather conditions, or prefers an electric drive system.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CT-300 stern
unverified
· 300.0 kW
· electric tunnel thruster
Power (kW)
300
Thrust (kN)
36.0
Diameter (mm)
740
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust-to-power ratio (36 kN at 300 kW) for its compact size
- Compact tunnel diameter (740 mm) fits vessels with limited hull space
- Electric drive offers low emissions, reduced noise and easier integration with ship automation systems
- Robust stainless‑steel housing and sealed motor reduces corrosion risk in marine environments
- Integrated control unit compatible with most DP and bridge control consoles
Weaknesses
- Requires significant hull penetration and reinforcement at the stern, increasing installation cost
- Power demand (300 kW) may be high for vessels with limited auxiliary generation capacity
- Maintenance of bearing and seal assemblies can be labour‑intensive compared to hydraulic units
- Thrust output may be insufficient for ice‑class or very large vessels needing >50 kN stern thrust
- Limited availability of spare parts in remote ports compared with more common 250 kW models
Typical Vessels:
Container ships (up to 5,000 TEU)Bulk carriers (handysize to panamax)Tanker (product and chemical)Offshore supply vesselsCruise ships and ferries requiring stern assistance
Certifications:
DNV GL ApprovalABS Classification
Decision Guide: Choose if: you need a high‑thrust, space‑efficient stern thruster on a vessel with sufficient electrical generation capacity and require low noise/emission operation (e.g., DP‑enabled offshore vessels or large commercial ships). Avoid if: the ship operates in ice conditions, has limited auxiliary power, or the installation budget cannot accommodate extensive hull reinforcement.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CT-500 bow
unverified
· 500.0 kW
· tunnel thruster
Power (kW)
500
Thrust (kN)
60.0
Diameter (mm)
900
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (60 kN @ 500 kW) for strong manoeuvring capability
- Compact tunnel geometry fits within limited hull space while providing effective wash‑down flow
- Integrated control electronics compatible with most DP and bridge control systems
- Proven reliability on offshore support vessels and medium‑size merchant ships
- Low vibration and noise due to enclosed impeller design
Weaknesses
- Relatively large tunnel diameter (900 mm) may limit installation in very narrow hull sections
- Fixed bow location; not suitable where stern thrust is required without additional unit
- Higher power demand (500 kW) increases fuel consumption when operated continuously
- Maintenance access can be restricted by the surrounding hull structure
Typical Vessels:
Offshore Supply VesselPlatform Support VesselMedium‑size Container ShipCruise FerryBulk Carrier (up to ~30 000 dwt)
Decision Guide: Choose if: you need strong bow thrust for tight berthing, dynamic positioning or low‑speed manoeuvring on vessels with sufficient hull space for a 900 mm tunnel. Avoid if: hull geometry cannot accommodate the tunnel size, or if a lower‑power, lighter thruster would meet the vessel’s maneuvering requirements.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CT-500 stern
unverified
· 500.0 kW
· high‑power tunnel thruster
Power (kW)
500
Thrust (kN)
60.0
Diameter (mm)
900
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (≈60 kN) suitable for large vessels and DP operations
- Compact tunnel geometry fits within limited hull space while providing strong lateral force
- Robust, marine‑grade construction with corrosion‑resistant lining for long service life
- Integrated control electronics compatible with most ship bridge automation systems
Weaknesses
- Relatively high power consumption (500 kW) increases fuel use and electrical load
- Large tunnel diameter may require significant hull penetration, affecting structural design
- Maintenance access can be restricted in tight stern spaces
- Higher initial cost compared with lower‑power thruster alternatives
Typical Vessels:
Container shipCrude oil tankerLNG carrierOffshore supply vesselCruise ship
Decision Guide: Choose if: the vessel requires strong stern thrust for dynamic positioning, tight‑port maneuvering, or high‑speed berthing and has sufficient electrical power capacity. Avoid if: the ship is small to medium size with limited budget, or hull design cannot accommodate a 900 mm tunnel without major modifications.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CT-750 bow
unverified
· 750.0 kW
· tunnel thruster
Power (kW)
750
Thrust (kN)
90.0
Diameter (mm)
1100
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (≈90 kN) relative to power rating (750 kW), giving strong manoeuvring capability.
- Compact tunnel diameter (1100 mm) fits into moderate‑size hull openings, reducing structural impact.
- Integrated control electronics from IHC/MSI provide smooth, low‑vibration operation and easy integration with DP systems.
- Proven track record on a variety of commercial vessels, offering reliability in harsh marine environments.
Weaknesses
- 750 kW electrical demand requires substantial power plant capacity and dedicated cooling.
- Installation involves significant hull penetration; retrofits can be costly and time‑consuming.
- Large tunnel size may limit use on smaller vessels or those with restricted bow space.
- Maintenance access is confined to the tunnel interior, requiring dry‑dock periods for major work.
Typical Vessels:
Container shipBulk carrierTankerCruise linerOffshore support vessel
Decision Guide: Choose if: you need high bow thrust for port entry, tight berthing or DP on vessels >30 000 dwt with sufficient power margin and bow space. Avoid if: the ship has limited electrical generation capacity, very narrow hull sections, or budget constraints that favour smaller‑rated thrusters.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CT-750 stern
unverified
· 750.0 kW
· tunnel thruster
Power (kW)
750
Thrust (kN)
90.0
Diameter (mm)
1100
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust‑to‑power ratio (≈90 kN @ 750 kW) for effective low‑speed control
- Robust steel tunnel housing with corrosion‑resistant lining reduces maintenance
- Integrated motor and propeller design minimises vibration and noise
- Compact installation footprint suitable for retrofits on existing stern sections
- Optional built‑in control electronics simplify integration with ship bridge systems
Weaknesses
- Large tunnel diameter (≈1.1 m) requires significant hull penetration and reinforcement
- Fixed thrust direction; no 360° vectoring compared with azimuth or pod thrusters
- Higher power consumption for the same manoeuvring performance as some azimuth units
- Potential cavitation at high RPMs if not properly matched to vessel speed profile
- Installation cost can be substantial due to structural modifications
Typical Vessels:
Container shipsCrude oil tankersProduct tankersBulk carriersCruise linersOffshore supply vessels
Decision Guide: Choose if: you need a high‑thrust, cost‑effective stern thruster for large vessels and can accommodate the tunnel opening; you require reliable DP support with proven class‑approved hardware. Avoid if: you need full 360° thrust vectoring, minimal hull penetration, or are limited by space constraints that favour azimuth pods.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CT-1000 bow
unverified
· 1000.0 kW
· tunnel thruster
Power (kW)
1000
Thrust (kN)
120.0
Diameter (mm)
1300
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output of 120 kN at 1 MW enables rapid side‑way movement.
- Large 1300 mm tunnel diameter reduces cavitation and improves hydraulic efficiency.
- Optimised for bow installation, providing effective flow around the hull form.
- Robust construction typical of IHC/MSI marine equipment enhances reliability.
- Suitable for vessels that need dynamic positioning assistance or tight‑port handling.
Weaknesses
- 1 MW power demand increases fuel consumption and may require dedicated generator capacity.
- Physical size (1300 mm diameter) limits installation to larger hulls and can reduce usable cargo space.
- Higher initial cost compared with lower‑power thruster alternatives.
- Installation often requires extensive hull modifications due to tunnel dimensions.
- Spare‑part availability could be limited if the manufacturer has a narrow distribution network.
Typical Vessels:
Container shipCruise linerLNG carrierVery Large Crude Carrier (VLCC)Offshore supply vessel
Decision Guide: Choose if the vessel exceeds ~30,000 GT and requires high lateral thrust for tight‑port maneuvering or dynamic positioning. Avoid on smaller ships where power budget is limited or hull space cannot accommodate a 1.3 m tunnel thruster.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CT-1000 stern
unverified
· 1000.0 kW
· Tunnel thruster
Power (kW)
1000
Thrust (kN)
120.0
Diameter (mm)
1300
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust-to-diameter ratio (120 kN) suitable for large vessels
- Robust single‑piece tunnel design reduces leakage and hull penetration points
- Integrated control system compatible with most bridge consoles
- Proven reliability in harsh marine environments
- Compact installation footprint compared to azimuth thrusters of similar power
Weaknesses
- High electrical power demand (1 000 kW) may require significant generator capacity
- Large tunnel diameter can reduce hull strength and increase construction complexity
- Limited thrust vectoring – fixed direction only, requiring helm coordination
- Maintenance access to the internal motor is more constrained than for external units
- Potential cavitation noise at full‑load operation
Typical Vessels:
Aframax tankerPanamax container shipCruise liner (mid‑size)Offshore supply vesselLNG carrier (medium size)
Decision Guide: Choose if: you need a high‑thrust stern thruster for vessels >30 000 gt, have sufficient onboard power generation, and require a proven, low‑maintenance solution. Avoid if: vessel design limits large tunnel openings, power budget is tight, or you need full 360° thrust vectoring.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CT-1500 bow
unverified
· 1500.0 kW
· large-diameter tunnel thruster
Power (kW)
1500
Thrust (kN)
180.0
Diameter (mm)
1700
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- High thrust output (180 kN) suitable for very large ships and DP operations
- Large tunnel diameter reduces cavitation risk and improves efficiency at high power
- Robust IHC/MSI design known for durability in harsh marine environments
- Integrated control electronics compatible with most bridge automation systems
Weaknesses
- High installed power (1 500 kW) leads to significant fuel consumption when used continuously
- Large tunnel size requires substantial hull penetration and structural reinforcement
- Maintenance access can be difficult due to the size of the unit
- Weight and centre‑of‑gravity impact must be carefully assessed during ship design
Typical Vessels:
Very Large Crude Carrier (VLCC)Ultra Large Container Vessel (ULCV)Cruise ShipLNG CarrierOffshore Supply Vessel
Decision Guide: Choose if: you need a high‑thrust bow thruster for vessels over 150 m LOA, require reliable DP capability, and have sufficient hull space for a 1.7 m tunnel. Avoid if: vessel size or power budget is limited, or if a smaller, lower‑power thruster would meet manoeuvring requirements.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
CT-1500 stern
unverified
· 1500.0 kW
· tunnel thruster
Power (kW)
1500
Thrust (kN)
180.0
Diameter (mm)
1700
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- High thrust output (180 kN) suitable for very large ships and tight port manoeuvring
- Large tunnel diameter (1.7 m) gives efficient water flow and reduced cavitation
- Robust stainless‑steel construction typical of IHC/MSI designs, known for long service life
- Integrated variable frequency drive allows fine thrust control and energy optimisation
- Modular installation kit simplifies retro‑fit into existing hull structures
Weaknesses
- Very high power demand (1 500 kW) increases fuel consumption when used extensively
- Requires substantial stern space and hull penetration, limiting applicability on smaller vessels
- Tunnel lining wear can lead to higher maintenance intervals in abrasive environments
- Noise and vibration levels are notable at full power, may need additional acoustic mitigation
- Initial capital cost is relatively high compared with smaller bow thrusters
Typical Vessels:
Crude oil tankerProduct tankerContainer ship (large class)Cruise linerOffshore supply vesselLNG carrier (mid‑size)
Decision Guide: Choose if: you need a high‑thrust stern thruster for vessels >30 000 gt that require precise low‑speed manoeuvring, dynamic positioning assistance or emergency thrust. Avoid if: vessel size or hull layout cannot accommodate a 1.7 m tunnel, power availability is limited, or budget constraints favour smaller bow‑type units.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
CT-2000 bow
unverified
· 2000.0 kW
· tunnel thruster
Power (kW)
2000
Thrust (kN)
240.0
Diameter (mm)
2100
Type
tunnel
Location
bow
Common Failures & Inspection Points
- Propeller or blade damage from debris can cause vibration and reduced thrust, noticed during maneuvering
- Gear or bearing wear can produce abnormal noise, heat or metallic debris in lubricant
- Seal leakage can allow water ingress or oil loss, seen through header-tank level changes or leakage alarms
- Motor, converter or hydraulic-drive faults can prevent commanded thrust, seen as trips, low power or unavailable thruster status
- Control or feedback-sensor faults can cause incorrect direction or pitch/azimuth indication, seen as command mismatch alarms
Service: Inspect drive machinery, lubrication, seals, bearings, propeller condition, control feedback and electrical or hydraulic interfaces. Review oil condition, leakage and vibration trends and verify correct response to bridge commands. Exact wear limits and service settings must follow manufacturer documentation.
Spare Parts: Carry approved seals, filters, sensors, control fuses, selected hydraulic or electrical service parts and other maker-recommended critical spares.
Strengths
- Very high thrust (≈240 kN) suitable for ships >150 m LOA requiring strong bow assistance
- Compact tunnel layout saves deck space compared with external azimuth units
- Integrated control and monitoring system compatible with most bridge consoles
- Robust ducted design reduces propeller cavitation and improves efficiency at high load
Weaknesses
- Large tunnel diameter (≈2.1 m) may limit installation on vessels with restricted hull space
- High power demand (≈2 MW) increases fuel consumption of auxiliary generators
- Maintenance requires access to the duct interior, which can be time‑consuming
- Noise and vibration transmitted through the hull are higher than for some low‑speed screw thrusters
Typical Vessels:
Container shipsCruise linersLNG carriersBulk carriersOffshore supply vessels
Decision Guide: Choose if: you need maximum bow thrust for a large vessel, have sufficient hull space for a ~2.1 m tunnel, and want an integrated control package. Avoid if: the ship’s design limits tunnel diameter, power budget is tight, or low‑noise/low‑vibration thrusters are a priority.
Use Cases: Used on ferries, offshore vessels, cruise ships, tugs and merchant ships requiring improved harbor maneuvering or station-keeping capability.
CT-2000 stern
unverified
· 2000.0 kW
· high‑power tunnel thruster
Power (kW)
2000
Thrust (kN)
240.0
Diameter (mm)
2100
Type
tunnel
Location
stern
Common Failures & Inspection Points
- Propeller fouling, rope entanglement or blade damage causes vibration, reduced thrust or high drive load
- Shaft-seal or gearbox leakage causes oil loss, water ingress or low-level alarms
- Bearing or gear wear causes abnormal noise, vibration or rising temperature
- Electric motor, converter or hydraulic-drive faults cause reduced thrust, failed starts or protective trips
- Pitch, steering or control-feedback faults as applicable cause incorrect thrust response, loss of direction control or remote-control alarms
Service: Inspect propeller and tunnel or retractable housing when accessible, seals, gearbox or bearings, lubrication, motor or hydraulic drive and control feedback. Review vibration, oil condition, temperature and thrust response. Test bridge and local control under an approved manoeuvring procedure. Refer to the manufacturer documentation for the exact figure for lubrication, clearance, electrical and wear limits.
Spare Parts: Carry seals, filters, approved lubricant, motor-control or drive spares, feedback sensors and critical hydraulic, steering or electrical components.
Strengths
- Very high thrust (240 kN) suitable for VLCC/ULCC size ships
- Large tunnel diameter reduces cavitation risk at high power levels
- Robust IHC/MSI design with proven reliability in harsh sea conditions
- Integrated control interface compatible with most DP systems
Weaknesses
- High electrical power demand (2 MW) increases fuel‑to‑electric load and installation cost
- Large hull penetration requires extensive structural reinforcement
- Limited to vessels with sufficient stern space; not ideal for smaller ships
- Installation and maintenance are more complex than smaller thrusters
Typical Vessels:
VLCCULCCLNG carrier (large)Large bulk carrierVery large container ship
Decision Guide: Choose if: you need maximum stern thrust for a vessel >150 kt deadweight, operate in confined ports or require DP2/DP3 capability on a large tanker. Avoid if: the ship is under 50 kt deadweight, power budget is limited, or space constraints favour azimuth pod thrusters.
Use Cases: Harbour manoeuvring, dynamic positioning and low-speed transverse or vectored thrust on merchant, passenger and offshore vessels.
ABB
1
ABB Marine Tunnel Thruster
· brushless AC tunnel thruster
Model Number
ABB TT (Tunnel Thruster)
Strengths
- High thrust efficiency due to optimized propeller geometry and low‑loss AC drive
- Compact installation footprint suitable for limited hull space
- Low maintenance thanks to brushless motor and corrosion‑resistant housing
- Integrated control system compatible with most vessel automation platforms
- Proven reliability on a wide range of commercial vessels
Weaknesses
- Higher upfront capital cost compared with basic DC thruster units
- Requires three‑phase power supply (typically 400 V) and dedicated control electronics
- Spare parts may have longer lead times in remote ports
- Installation can be complex on existing hulls due to tunnel machining requirements
Typical Vessels:
Container ShipBulk CarrierTankerCruise ShipOffshore Support Vessel
Certifications:
IMO D-2DNV GL
Decision Guide: Choose if: you need a high‑efficiency, low‑maintenance thruster for vessels with limited bow/stern space and have the required three‑phase power infrastructure. Avoid if: budget constraints prioritize lowest initial cost or if operating in regions where spare‑part logistics are severely limited.
Use Cases: ABB tunnel thrusters are commonly installed on new builds and retrofits to improve low‑speed maneuverability in ports, aid dynamic positioning for offshore support vessels, and provide precise bow‑thruster control on cruise ships during docking operations.
PMH Norway
1
PMH STR100-500, PMH STR130-750
Model Number
TAM00001BH
Rolls-Royce Marine
1
TT-2200-CP
2200 kW
· 2200.0 kW
· Seawater
· controllable‑pitch tunnel thruster
Common Failures & Inspection Points
- Hydraulic leakage or low oil level causes reduced pressure, slow movement or low-level alarms
- Pump, motor or drive faults cause loss of one power unit, reduced thrust or failure to move the rudder
- Control, feedback or position-sensor faults cause hunting, incorrect indication or failure to reach the commanded position
- Bearing, seal or mechanical wear causes vibration, leakage, backlash or abnormal noise
- Air ingress, contamination or cooling faults cause unstable hydraulic or drive performance and protective trips
Service: Inspect power units, oil or lubrication condition, actuators or thruster drive, seals, feedback transmitters, controls and structural connections. Test main, standby and emergency arrangements according to the approved vessel and class procedure. Check leakage, vibration and response throughout the operating range. Refer to the manufacturer documentation for the exact figure for pressure, alignment and wear limits.
Spare Parts: Carry hydraulic filters, seals, hose or pipe repair provisions, motor-control spares, feedback sensors, relays, fuses and critical valve or drive service parts.
Strengths
- Variable pitch allows precise thrust direction and magnitude without changing shaft speed
- Compact tunnel installation suitable for both bow and stern locations
- Proven Rolls‑Royce (now Kongsberg Maritime) design with integrated VFD control
- Gearbox can be inspected during scheduled dry‑dock, simplifying maintenance planning
Weaknesses
- Blade pitch mechanism is a known failure point requiring regular inspection
- Higher mechanical complexity leads to increased maintenance compared with fixed‑pitch thrusters
- Gear bearing wear and seal failures have been reported in service history
- VFD trips can occur if power quality or control parameters are not optimised
Typical Vessels:
Container shipCruise linerOffshore supply vesselLNG carrierTanker
Decision Guide: Choose if the vessel needs fine, variable thrust for docking or dynamic positioning and can accommodate the additional maintenance of a pitch mechanism. Avoid if budget constraints favour simpler fixed‑pitch thrusters or if maintenance resources are limited.
Use Cases: Steering and harbour manoeuvring on merchant, passenger, offshore and work vessels.
Sleipner Motor
1
SAC360, SAC400, SAC550, SAC700, SAC750, SAC900, SAC950, SAC1000, SAC1100, SAC1300, SAC1400, SAC2200, SH360, SH400, SH420, SH700, SH1000, SH1400, SH2200, SRAC320, SRHP240, SRHP320, SRHP650, ERV130, ERV170, ERV210, ERL130, ERL170, SRL130, SRL170, SRV130, SRV170, SRV210, ERV250, ERV300, SRV300
Model Number
TAM00000DT