Radar Plot System (ARPA)
critical
IMO Required
11 models total
ARPA takes a standard radar picture and adds automatic target tracking, converting echoes into vectors with a computed closest point of approach, which is what turns a radar screen into a collision-avoidance tool rather than just a picture of the surrounding traffic.
Read more — Radar Plot System (ARPA) explained ▾
What Sets ARPA Apart from Plain Radar
A basic marine radar shows raw echoes and lets the officer of the watch plot targets by hand, marking bearing and range at intervals on a reflection plotter. ARPA automates that plotting: once a target is acquired, the processor tracks it across successive sweeps and computes course, speed, closest point of approach (CPA) and time to closest point of approach (TCPA) continuously, updating a vector display without the watchkeeper doing the arithmetic. The value is not the tracking alone but the trial manoeuvre function, which lets the bridge team test a proposed course or speed change against all tracked targets before actually altering the ship's heading.
Main Components
Scanner and Transceiver
The rotating antenna and its transmitter/receiver unit are shared with the base radar; ARPA is a processing and display layer built on top, most often the X-band set for target detail with an S-band set on larger ships for tracking in heavy rain or sea clutter.
Tracking Processor
Software correlates successive echo returns from the same target, filters out clutter and applies a tracking algorithm, typically a form of alpha-beta or Kalman filter, to smooth the target's estimated course and speed.
Display and Vector Presentation
Targets appear with a velocity vector in either true or relative motion mode, vector length scaled to a chosen time interval so the watchkeeper can read closing speed at a glance rather than reading numbers off a data box.
Trial Manoeuvre Function
The operator inputs a hypothetical own-ship course or speed change and the system projects how CPA and TCPA against every tracked target would change, without committing the ship to the manoeuvre.
Selection and Sizing
The relevant figures are tracking capacity, minimum 20 simultaneous targets under the IMO performance standard, and the number of targets the display remains readable with in dense traffic. Antenna length and transmitter power are chosen for the ship's expected range requirements rather than for ARPA itself, since the tracking layer works with whatever raw picture the scanner delivers.
Regulations and Class
- SOLAS Chapter V, Regulation 19 sets the carriage requirement for radar and automatic tracking aids by ship size and type; large ships on international voyages need both an X-band set and a second radar, commonly S-band, each capable of ARPA tracking.
- IMO Resolution A.823(19) is the performance standard ARPA equipment must meet, covering minimum tracking accuracy, target capacity and trial manoeuvre function.
- STCW requires bridge officers to hold ARPA-specific training and certification separate from general radar observer courses, since misreading a vector display has been a contributing factor in collision cases.
Typical Faults
| Fault | Consequence |
|---|---|
| Gyro or speed log input drops out or freezes | Tracked vectors compute against stale heading and speed data, CPA and TCPA become unreliable |
| Sea clutter setting too aggressive in heavy weather | Small craft or debris lost from tracking, false sense of a clear picture |
| Scanner motor bearing wear | Irregular rotation speed degrades tracking accuracy before the fault is visually obvious |
| Software target swap in close-quarters traffic | System assigns one target's vector to a different nearby contact, giving a false CPA |
What to Look for in a Supplier
- Type approval certificate confirming compliance with the current IMO performance standard for the specific software version installed, since ARPA firmware is revised periodically.
- Interface compatibility with the ship's existing gyro, speed log and AIS feeds without a separate signal converter for each.
- Training support and simulator access for officers converting from an older display to a new touchscreen or multifunction bridge system.
Treat the trial manoeuvre output as a planning aid, not a guarantee: it only knows what the tracked targets are doing at the moment of the trial, and a target that alters course after you commit to your own manoeuvre will not update the projection you already acted on.
5 yr
Class Survey
15 yr
Typical Lifetime
Typical Manufacturers
JRC
Furuno
Sperry Marine
7 manufacturers · 11 models
Framo Holsnøy
2
Framo Flexible And Gastight Class A-0 And A-60 Penetration Sealing System
X-Band / S-Band, IMO SOLAS
· Electromagnetic Radar
· Flexible gastight cable penetration seal
Common Failures & Inspection Points
- Magnetron end-of-life after 5,000–8,000 operating hours (for magnetron models)
- Antenna rotation motor bearing damage after 30,000+ hours
- Display backlight failure
- Heading-Marker Ausrichtungsdrift
- Waveguide moisture ingress during compromised pressurization
Service: Magnetron replacement every 5,000–8,000 hours. Antenna bearing lubrication annually. Performance monitor test weekly (IMO requirement). Annual inspection.
Spare Parts: Framo Holsnøy AS: Keep magnetron on board (for magnetron models). Lead time: 1-3 weeks.
Strengths
- Provides a reliable watertight barrier for rotating or flexing cable bundles
- Certified to Class A‑0 and A‑60 pressure ratings (up to 6 bar static, 1 bar dynamic)
- Accommodates a wide range of cable diameters with interchangeable inserts
- Easy to install and service without dismantling surrounding structures
Weaknesses
- Requires precise sizing; mismatched insert sizes can compromise seal performance
- Higher unit cost compared with basic static cable glands
- Periodic inspection needed to verify integrity after heavy vibration or impact
- Limited to applications where pressure class A‑0/A‑60 is required
Typical Vessels:
TankerContainer shipBulk carrierOffshore supply vesselCruise liner
Decision Guide: Choose if: you need a flexible, high‑pressure (A‑60) seal for rotating radar or antenna cables and want proven watertight performance under dynamic conditions. Avoid if: the penetration is static, budget constraints dominate, or lower pressure class seals are sufficient.
Use Cases: Commonly installed at the deck‑house or mast where radar antennas rotate, protecting cable entries from seawater ingress while allowing full azimuth movement; also used for other moving penetrations such as winch control cables on offshore vessels.
FRAMO "RGP" – RESILIENT AND GASTIGHT CLASS A-0 PENETRATION SEALING SYSTEM
X-Band / S-Band, IMO SOLAS
· Electromagnetic Radar
· Class A-0 gastight penetration seal
Common Failures & Inspection Points
- Magnetron end-of-life after 5,000–8,000 operating hours (for magnetron models)
- Antenna rotation motor bearing damage after 30,000+ hours
- Display backlight failure
- Heading-Marker Ausrichtungsdrift
- Waveguide moisture ingress during compromised pressurization
Service: Magnetron replacement every 5,000–8,000 hours. Antenna bearing lubrication annually. Performance monitor test weekly (IMO requirement). Annual inspection.
Spare Parts: Framo Holsnøy AS: Keep magnetron on board (for magnetron models). Lead time: 1-3 weeks.
Strengths
- Provides Class A‑0 level watertight protection for rotating radar antennas, meeting high safety standards.
- Resilient sealing material tolerates vibration, temperature swings and marine corrosion.
- Simple annual lubrication of the antenna bearing reduces maintenance effort.
- Compatible with a wide range of radar manufacturers and antenna sizes.
- Allows continuous radar operation without compromising hull integrity.
Weaknesses
- Magnetron units have limited service life (5 000‑8 000 h) requiring periodic replacement.
- Antenna rotation motor bearings may develop wear after 30 000+ h of operation.
- Moisture ingress can occur if pressure monitoring of the seal fails.
- Replacement or overhaul of the sealing assembly is a specialised task, potentially costly.
- Associated ARPA display issues (background illumination failure, heading‑marker drift) can affect situational awareness.
Typical Vessels:
TankerOffshore supply vesselCruise shipContainer shipBulk carrier
Decision Guide: Choose the FRAMO RGP when a vessel requires a high‑integrity, Class A‑0 watertight penetration for its rotating radar antenna and operates in harsh sea conditions. Avoid if budget constraints limit the ability to perform the required regular maintenance or if a simpler non‑penetrating antenna solution is acceptable.
Use Cases: The system is typically installed on large commercial vessels where continuous radar coverage is critical, such as tankers navigating congested waterways, offshore support ships operating in rough seas, and cruise liners that must meet stringent SOLAS watertight standards.
Kelvin Hughes
2
S & X Band Radar Navigation System
X-Band / S-Band, IMO SOLAS
· Electromagnetic Radar
· dual-band X/S ARPA radar
Common Failures & Inspection Points
- Magnetron end-of-life after 5,000–8,000 operating hours (for magnetron models)
- Antenna rotation motor bearing damage after 30,000+ hours
- Display backlight failure
- Heading-Marker Ausrichtungsdrift
- Waveguide moisture ingress during compromised pressurization
Service: Magnetron replacement every 5,000–8,000 hours. Antenna bearing lubrication annually. Performance monitor test weekly (IMO requirement). Annual inspection.
Spare Parts: Kelvin Hughes Ltd: Keep magnetron on board (for magnetron models). Lead time: 1–3 weeks.
Strengths
- Dual‑band operation gives superior performance in rain and sea clutter compared with single‑band radars.
- Integrated ARPA automatically tracks multiple targets and meets IMO Performance Monitoring requirements.
- Standard interface to most ECDIS platforms simplifies bridge integration.
- Proven mechanical rotating antenna delivers long‑range detection (up to 96 nm) for open‑sea navigation.
- Well‑documented maintenance schedule (magnetron replacement, bearing lubrication) supports predictable life‑cycle costs.
Weaknesses
- Magnetron has a limited service life (5 000–8 000 h), requiring costly periodic replacement.
- Mechanical rotating antenna introduces wear points (bearing damage after ~30 000 h).
- Higher power consumption and larger footprint than solid‑state, phased‑array alternatives.
- Display back‑light failures have been reported, necessitating spare modules.
- Heading‑marker drift can affect target bearing accuracy if not regularly calibrated.
Typical Vessels:
Passenger ferriesCruise shipsOffshore support vesselsNaval patrol craftBulk carriers
Certifications:
IMO Performance Standard (D‑2)USCG Type Approval
Decision Guide: Choose if you need reliable dual‑band detection, ARPA capability and seamless ECDIS integration for vessels operating in congested or adverse weather areas. Avoid if budget constraints favour solid‑state phased‑array radars with lower maintenance overhead or if the vessel’s operational profile does not require long‑range detection.
Use Cases: The system is typically installed on passenger and offshore vessels that navigate busy ports, coastal waters and open seas where rain attenuation and sea clutter are common. It supports collision avoidance, safe berthing, and bridge watch‑keeping in heavy traffic zones.
S & X Band Radar Navigation System (CAT 2)
X-Band / S-Band, IMO SOLAS
· Electromagnetic Radar
· dual‑band S/X marine radar with ARPA
Common Failures & Inspection Points
- Magnetron end-of-life after 5,000–8,000 operating hours (for magnetron models)
- Antenna rotation motor bearing damage after 30,000+ hours
- Display backlight failure
- Heading-Marker Ausrichtungsdrift
- Waveguide moisture ingress during compromised pressurization
Service: Magnetron replacement every 5,000–8,000 hours. Antenna bearing lubrication annually. Performance monitor test weekly (IMO requirement). Annual inspection.
Spare Parts: Kelvin Hughes Ltd: Keep magnetron on board (for magnetron models). Lead time: 1–3 weeks.
Strengths
- Dual‑band (S & X) operation reduces rain clutter and improves target discrimination
- Meets IMO Performance Standard Category 2 for ARPA accuracy and update rate
- Proven track record on a wide range of merchant vessels
- Modular design allows separate antenna, display and processing units for flexible installation
- Integrated ARPA functions reduce the need for separate collision‑avoidance equipment
Weaknesses
- Magnetron life limited to 5 000–8 000 operating hours requiring scheduled replacement
- Mechanical rotating antenna subject to bearing wear after ~30 000 h, increasing maintenance
- Higher routine maintenance (bearing lubrication, magnetron monitoring) compared with solid‑state radars
- Display back‑light and heading‑marker drift issues reported in older installations
- Waveguide moisture ingress possible if pressure sealing is compromised
Typical Vessels:
Container shipGeneral cargo vesselBulk carrierPassenger ferryOffshore supply vessel
Certifications:
IMO Performance Standard CAT 2
Decision Guide: Choose if you need reliable dual‑band target detection, must comply with IMO Category 2 ARPA requirements, and have an existing Kelvin Hughes infrastructure. Avoid if you prefer low‑maintenance solid‑state radars, have very limited maintenance budgets, or operate vessels where weight and space constraints favour newer compact units.
Use Cases: Deployed on merchant ships for navigation in congested sea lanes, port approaches, and adverse weather; used for collision avoidance, target tracking, and situational awareness during offshore operations.
MAN Energy Solutions
2
ME-GA Secondary Fuel System
X-Band / S-Band, IMO SOLAS
· Electromagnetic Radar
· ARPA radar
Common Failures & Inspection Points
- Magnetron end-of-life after 5,000–8,000 operating hours (for magnetron models)
- Antenna rotation motor bearing damage after 30,000+ hours
- Display backlight failure
- Heading-Marker Ausrichtungsdrift
- Waveguide moisture ingress during compromised pressurization
Service: Magnetron replacement every 5,000–8,000 hours. Antenna bearing lubrication annually. Performance monitor test weekly (IMO requirement). Annual inspection.
Spare Parts: MAN Energy Solutions, branch of MAN Energy Solutions SE, Germany: keep magnetron on board (for magnetron models). Lead time: 1-3 weeks.
Strengths
- Automatic target acquisition and plotting reduces crew workload
- Provides CPA/DCPA data for enhanced collision avoidance
- Integration capability with ECDIS for seamless navigation display
- Standard ARPA functions (track history, speed vector overlay)
- Relatively compact installation suitable for various vessel sizes
Weaknesses
- Magnetron has a limited service life of 5 000–8 000 operating hours
- Antenna rotation motor bearings prone to wear after ~30 000 hours
- Display back‑light failures reported in field service notes
- Heading marker can drift, requiring periodic recalibration
- Waveguide moisture ingress possible if pressure sealing is compromised
Typical Vessels:
Container shipBulk carrierTankerPassenger vesselOffshore supply vessel
Decision Guide: Choose if you need a proven ARPA radar with ECDIS integration and can accommodate scheduled magnetron replacement and bearing lubrication. Avoid if low‑maintenance, long‑life transmitter technology is required or the vessel operates in very high humidity environments where waveguide moisture could be an issue.
Use Cases: Deployed on ocean‑going merchant vessels for bridge navigation, providing continuous target tracking and collision avoidance support during all weather conditions, especially on routes with dense traffic.
SaCoS_one System
X-Band / S-Band, IMO SOLAS
· Electromagnetic Radar
· Integrated ARPA radar‑plot system
Common Failures & Inspection Points
- Magnetron end-of-life after 5,000–8,000 operating hours (for magnetron models)
- Antenna rotation motor bearing damage after 30,000+ hours
- Display backlight failure
- Heading-Marker Ausrichtungsdrift
- Waveguide moisture ingress during compromised pressurization
Service: Magnetron replacement every 5,000–8,000 hours. Antenna bearing lubrication annually. Performance monitor test weekly (IMO requirement). Annual inspection.
Spare Parts: MAN Energy Solutions SE: keep magnetron on board (for magnetron models). Lead time: 1-3 weeks.
Strengths
- Combines X‑band radar, ARPA processing and ECDIS in a single cockpit unit, reducing space and wiring complexity
- DNV‑approved design with built‑in performance monitoring that satisfies IMO weekly test requirements
- Modular hardware (magnetron, antenna motor, display) allows relatively quick replacement during scheduled maintenance
- High target‑tracking accuracy with automatic heading‑marker alignment when calibrated
- Standardised service intervals (magnetron exchange every 5 000–8 000 h, annual bearing lubrication) simplify planning
Weaknesses
- Magnetron life limited to 5 000–8 000 operating hours, requiring costly replacement at relatively short intervals
- Antenna rotation motor bearings can develop wear after 30 000+ hours, leading to potential drift if not lubricated annually
- Display back‑light failures have been reported, affecting night‑time readability until repaired
- Heading‑marker alignment may drift over time and needs regular verification
- Waveguide moisture ingress can occur if pressure sealing is compromised, necessitating careful enclosure maintenance
Typical Vessels:
TankerContainer shipBulk carrierCruise linerOffshore supply vessel
Certifications:
DNV
Decision Guide: Choose if you need a single, DNV‑approved bridge unit that merges radar ARPA and ECDIS functions, you operate vessels >10 000 GT where cockpit space is at a premium, and you can accommodate the scheduled magnetron and bearing maintenance. Avoid if initial cost sensitivity outweighs integration benefits, you prefer separate radar/ECDIS systems for redundancy, or your operational profile cannot tolerate the relatively frequent magnetron replacements.
Use Cases: The SaCoS_one is typically installed on large merchant vessels navigating congested sea lanes or high‑traffic ports, providing collision‑avoidance ARPA tracking while simultaneously displaying electronic charts. It is also used on cruise ships and offshore supply vessels where integrated situational awareness improves bridge workload management.
Optimarin
2
Name of BWMS: Optimarin Ballast System (OBS) Capacities: 65-3,000 m3/h (intake), 167-3,000 m3/h (discharge)
X-Band / S-Band, IMO SOLAS
· Electromagnetic Radar
· Filtration + UV disinfection
Common Failures & Inspection Points
- Magnetron end-of-life after 5,000–8,000 operating hours (for magnetron models)
- Antenna rotation motor bearing damage after 30,000+ hours
- Display backlight failure
- Heading-Marker Ausrichtungsdrift
- Waveguide moisture ingress during compromised pressurization
Service: Magnetron replacement every 5,000–8,000 hours. Antenna bearing lubrication annually. Performance monitor test weekly (IMO requirement). Annual inspection.
Spare Parts: Optimarin AS: Keep magnetron on board (for magnetron models). Lead time: 1–3 weeks.
Strengths
- Compact, modular design suitable for a wide range of vessel sizes
- Low power consumption compared with chemical systems
- Scalable flow capacity from 65 m³/h up to 3 000 m³/h
- Proven compliance with IMO D‑2 and USCG Type Approval
- Simple integration with existing ballast piping
Weaknesses
- Maximum rated flow of 3 000 m³/h may be insufficient for very large tankers or cruise ships
- UV lamps require periodic replacement (typically every 12 months) to maintain efficacy
- High‑pressure pumps increase maintenance workload
- Initial capital cost higher than basic filtration‑only solutions
Typical Vessels:
Bulk carrierContainer shipProduct tankerGeneral cargo vesselOffshore supply vessel
Certifications:
IMO D-2 Type ApprovalUSCG Type ApprovalDNV Class Approval
Decision Guide: Choose OBS if you need a compact, energy‑efficient BWMS that can be scaled across small to medium vessels and must meet IMO/USCG regulations. Avoid it for ultra‑large ships requiring flow rates above 3 000 m³/h or where budget constraints preclude the higher upfront cost of UV technology.
Use Cases: Optimarin OBS is commonly installed on new builds as part of the ballast water treatment package and on retrofits where space and power are limited, such as mid‑size bulk carriers, container vessels, and offshore support ships operating in regulated waters.
Optimarin Ballast System "Optimarin Protector": 167/72BK3 - 3000/3100BK3, 167/65BK4 - 3000/2600BK4, 167/87FX2 - 3000/3000FX2, P167/72BK3 - P3000/3100BK3, P167/65BK4 - P3000/2600BK4 and P167/87FX2 - P3000/3000FX2
X-Band / S-Band, IMO SOLAS
· Electromagnetic Radar
· magnetron‑based X‑band radar with ARPA
Common Failures & Inspection Points
- Magnetron end-of-life after 5,000–8,000 operating hours (for magnetron models)
- Antenna rotation motor bearing damage after 30,000+ hours
- Display backlight failure
- Heading-Marker Ausrichtungsdrift
- Waveguide moisture ingress during compromised pressurization
Service: Magnetron replacement every 5,000–8,000 hours. Antenna bearing lubrication annually. Performance monitor test weekly (IMO requirement). Annual inspection.
Spare Parts: Optimarin AS: Keep magnetron on board (for magnetron models). Lead time: 1–3 weeks.
Strengths
- Built‑in ARPA functionality with multiple target tracks and predictive plotting
- Modular design allows quick magnetron replacement (5 000–8 000 h service interval)
- DNV class approval ensures compliance with major classification societies
- Standardised weekly performance‑monitor test satisfies IMO requirements
- Annual lubrication of antenna rotation motor reduces long‑term wear
Weaknesses
- Magnetron life limited to 5 000–8 000 operating hours, requiring scheduled replacement
- Antenna rotation motor bearings can develop damage after 30 000+ hours if not serviced
- Display backlight failures have been reported, affecting night‑time visibility
- Heading‑marker drift may require frequent recalibration
- Waveguide moisture ingress possible when pressure sealing is compromised
Typical Vessels:
TankerContainer shipBulk carrierCruise linerOffshore supply vessel
Certifications:
DNV class approval
Decision Guide: Choose if you need a proven ARPA radar with DNV endorsement, have maintenance capability for scheduled magnetron and bearing service, and operate vessels where high‑resolution target tracking is critical. Avoid if you prefer solid‑state radars with longer component life, have limited access to annual mechanical servicing, or operate small craft where the system’s size and power demand are excessive.
Use Cases: Optimarin Protector is typically installed on deep‑sea merchant ships navigating congested routes, in offshore support vessels operating near platforms, and on cruise ships requiring reliable collision‑avoidance performance under all weather conditions. It is often integrated with ECDIS for seamless situational awareness.
Consilium Marine & Safety
1
Addressable-Conventional Modular System 7000-1MC-MED
X-Band / S-Band, IMO SOLAS
· Electromagnetic Radar
· Modular ARPA radar system
Common Failures & Inspection Points
- Magnetron end-of-life after 5,000–8,000 operating hours (for magnetron models)
- Antenna rotation motor bearing damage after 30,000+ hours
- Display backlight failure
- Heading-Marker Ausrichtungsdrift
- Waveguide moisture ingress during compromised pressurization
Service: Magnetron replacement every 5,000–8,000 hours. Antenna bearing lubrication annually. Performance monitor test weekly (IMO requirement). Annual inspection.
Spare Parts: Consilium Marine & Safety AB: magnetron to be kept on board (for magnetron models). Lead time: 1-3 weeks.
Strengths
- Addressable modular design allows quick identification and replacement of faulty modules
- Integrated ARPA provides automatic target tracking and collision‑avoidance calculations
- Meets IMO weekly performance‑monitor test requirement out‑of‑the‑box
- Defined maintenance intervals (magnetron swap 5 000–8 000 h, annual bearing lubrication) simplify planning
- DNV‑approved, giving confidence in classification compliance
Weaknesses
- Magnetron has a limited service life (5 000–8 000 operating hours)
- Antenna rotation motor bearings can develop wear after ~30 000 h
- Display back‑light and heading‑marker may drift or fail, requiring periodic checks
- Waveguide moisture ingress possible if pressure sealing is compromised
- Annual inspection and weekly performance tests add to crew workload
Typical Vessels:
TankerContainer shipBulk carrierCruise linerOffshore supply vessel
Certifications:
DNV
Decision Guide: Choose if you need a radar with built‑in ARPA, modular fault isolation and proven DNV approval for medium to large merchant vessels. Avoid if operating hours will regularly exceed the magnetron life limit without scheduled replacement or if budget constraints make frequent component swaps undesirable.
Use Cases: Deployed on ocean‑going commercial ships as the primary navigation radar, providing real‑time target tracking, collision avoidance and seamless data feed to the ship's ECDIS for route planning and monitoring.
Kongsberg Maritime
1
K-Bridge and K-Bridge Standalone system platforms
X-Band / S-Band, IMO SOLAS
· Electromagnetic Radar
· Integrated bridge navigation system with ARPA radar
Common Failures & Inspection Points
- Magnetron end-of-life after 5,000–8,000 operating hours (for magnetron models)
- Antenna rotation motor bearing damage after 30,000+ hours
- Display backlight failure
- Heading-Marker Ausrichtungsdrift
- Waveguide moisture ingress during compromised pressurization
Service: Magnetron replacement every 5,000–8,000 hours. Antenna bearing lubrication annually. Performance monitor test weekly (IMO requirement). Annual inspection.
Spare Parts: Kongsberg Maritime AS: Hold magnetron on board (for magnetron models). Lead time: 1–3 weeks.
Strengths
- Fully integrated radar, ARPA and ECDIS reduces operator workload and wiring complexity
- High‑capacity target tracking (up to 200 tracks) with automatic collision‑avoidance calculations
- Modular architecture allows standalone operation or full K‑Bridge suite for redundancy
- Meets IMO Performance Standard for ARPA and supports weekly performance monitoring tests
- Proven class approvals (DNV, USCG) and extensive service network
Weaknesses
- Magnetron life limited to 5 000–8 000 h; regular replacement adds operational cost
- Antenna rotation motor bearings can develop wear after ~30 000 h, requiring annual lubrication
- Display back‑light failures and heading‑marker drift have been reported in older units
- Waveguide moisture ingress possible if pressure sealing is compromised
- Higher upfront capital expense compared with basic radar‑only solutions
Typical Vessels:
TankerContainer shipBulk carrierCruise linerOffshore supply vesselRo‑Ro ferry
Certifications:
IMO D-2 (ARPA performance standard)USCG Type ApprovalDNV class approval
Decision Guide: Choose if: you need a single, integrated bridge suite with proven ARPA performance, high traffic density operation, and full class approvals. Avoid if: budget constraints prioritize low‑cost radar only, or you prefer an open‑architecture system without proprietary integration.
Use Cases: Deployed on ocean‑going merchant vessels and passenger ships where continuous collision avoidance, route planning and regulatory compliance are critical—especially in congested sea lanes, narrow straits, and offshore operations requiring precise navigation data.
SKF Sverige
1
SKF Multilog IMx-8 and IMx-16 On-line System
X-Band / S-Band, IMO SOLAS
· Electromagnetic Radar
· ARPA radar plot
Common Failures & Inspection Points
- Magnetron end-of-life after 5,000–8,000 operating hours (for magnetron models)
- Antenna rotation motor bearing damage after 30,000+ hours
- Display backlight failure
- Heading-Marker Ausrichtungsdrift
- Waveguide moisture ingress during compromised pressurization
Service: Magnetron replacement every 5,000–8,000 hours. Antenna bearing lubrication annually. Performance monitor test weekly (IMO requirement). Annual inspection.
Spare Parts: SKF Sverige AB: Hold magnetron on board (for magnetron models). Lead time: 1–3 weeks.
Strengths
- Integrated with ECDIS for seamless navigation data exchange
- Automatic target acquisition and tracking reduces crew workload
- High‑resolution display supports multiple targets simultaneously
- On‑line performance monitoring satisfies IMO weekly test requirements
Weaknesses
- Magnetron must be replaced every 5,000–8,000 operating hours
- Antenna rotation motor bearing wear after roughly 30,000 h requires regular lubrication or replacement
- Display backlight can fail, affecting visibility in low‑light conditions
- Heading‑marker alignment may drift and need frequent calibration
- Waveguide moisture ingress possible if pressure sealing is compromised
Decision Guide: Choose this system if you require an ARPA solution tightly coupled with ECDIS and can accommodate the scheduled component replacements (magnetron, bearing lubrication). Avoid it on vessels where maintenance windows are extremely limited or where a longer‑life magnetron is a priority.
Use Cases: Deployed on commercial ships that operate in congested sea lanes or restricted waters—such as tankers, container vessels, bulk carriers and passenger ferries—that need advanced collision‑avoidance capabilities integrated with their navigation suite.