NPT45RB Rescue Boat

Common issues

• On-load release hook mechanism sticking, corroding, or requiring excessive force to operate
• Hydrostatic interlock (preventing on-load release before waterborne) misalignment or failure
• Engine starting failure from battery neglect or fuel system issues after long periods of inactivity
• GRP hull gelcoat cracking or delamination, particularly at the keel/skid area from repeated launches or heavy weather
• Cradle/ramp corrosion or seized rollers preventing a clean freefall launch
• Painter or release line chafing or incorrect rigging
• Engine cooling water intake blockage after periods of lay-up

Inspection checklist

• Weekly external visual inspection and boat equipment check per SOLAS
• Monthly launch (weather/operationally permitting) or lowering into the water with engine run
• Annual thorough examination by a competent person per MSC.1/Circ.1206 as amended
• 5-yearly on-load release gear dynamic test and load test
• Check hull condition - gelcoat, structural attachment points, skid/keel wear
• Check engine starting, cooling water flow, and fuel system condition
• Check on-load release hook, hydrostatic interlock, and reset mechanism function
• Check cradle, ramp rollers, and retaining/release gear for corrosion or seizure
• Verify boat equipment inventory (per SOLAS list) is complete and in date
• Check the painter and painter release mechanism

Service intervals

Critical spares

• On-load release hook and hydrostatic interlock components
• Engine starting battery of the sealed marine type specified for lifeboat use
• Engine cooling water pump impeller kit
• Fuel filters
• Painter line and release mechanism components

Safety

• Freefall launching subjects occupants to significant deceleration forces - crew must be seated and braced correctly per the drill procedure
• Premature or failed on-load release gear is a major historical cause of LSA-related fatalities and injuries during drills - treat any doubt about this mechanism as a stop-work issue
• The hydrostatic interlock must be proven to prevent on-load release before the boat is waterborne, every time it is tested
• The confined engine compartment inside the boat requires ventilation before starting/running checks

Class survey

Class specifically checks the annual thorough examination and 5-year on-load release gear test records for the freefall system, along with hull condition at the skid/keel; a lapsed 5-year test is treated seriously given the LSA casualty history behind the MSC.1/Circ.1206 amendments.

Estimated lifetime: Not an hours-rated item; GRP freefall lifeboats are commonly kept in service for the vessel's operating life (often 20-25+ years) provided hull condition, release gear, and interlocks continue to pass thorough examination and the 5-yearly test - renewal is condition-driven, not hours-driven.