What to check on a Rescue Boat Davit.
A rescue boat davit exists to get a rescue boat into the water fast enough to reach a person overboard, and back aboard fast enough to be ready again. That duty cycle is the difference from a lifeboat davit: rescue boats are launched and recovered routinely, in drills and in service, not just in a genuine abandon-ship, so the davit, winch and fall arrangement see far more cycles and are rated for launch and recovery in a seaway up to the sea state stated in the ship's approval, not just…
What defines a rescue boat davit
A rescue boat davit exists to get a rescue boat into the water fast enough to reach a person overboard, and back aboard fast enough to be ready again. That duty cycle is the difference from a lifeboat davit: rescue boats are launched and recovered routinely, in drills and in service, not just in a genuine abandon-ship, so the davit, winch and fall arrangement see far more cycles and are rated for launch and recovery in a seaway up to the sea state stated in the ship's approval, not just calm-water conditions.
Main components
Davit arm and slewing mechanism
Gravity or hydraulically slewed arm that swings the stowed boat out over the ship's side. Single-arm radial davits are common for smaller rescue boats; larger combined lifeboat and rescue boat installations use the same davit for both duties.
Winch and brake
Powered winch lowers and, critically, recovers the boat under load, including recovery with the crew still aboard. The brake must hold the boat at any point in the lower and must not allow a free-fall descent — a failed or worn brake is the classic cause of a davit accident.
Wire falls and hook
Falls run from the winch drum through sheaves to the boat's release hook. On-load release hooks let the boat crew release from the falls with way on and under load in a seaway; off-load hooks release only once the boat is waterborne and the falls are slack.
Limit switches and remote control
End-of-travel limit switches stop the winch at full stow and full pay-out; a portable control pendant lets the boat crew or a deck operator run the davit from a safe position rather than standing directly under the load.
Selection and sizing
- Safe working load against the fully loaded rescue boat weight plus crew, with the required margin above that
- Launch and recovery speed matched to the rescue boat capacity approval and the time-to-launch target
- Sea state and list/trim angle the davit is approved to operate at, since a davit rated only for upright, calm conditions is of limited use in the scenario it exists for
- Compatibility of the hook type with the boat's release gear — davit and hook are approved as a matched set, not interchangeable components
Regulations and class
Davits fall under SOLAS Ch. III and the LSA Code, which set launching appliance requirements including the ability to recover the rescue boat with its full complement embarked. Class societies survey the winch brake, wire falls and hook release gear on the LSA five-yearly overhaul cycle, with load testing of the winch and dynamic testing of on-load release hooks at defined intervals — a requirement that has tightened across the industry after several fatal davit failures traced to worn hooks and brakes.
Typical faults
| Fault | Consequence |
|---|---|
| Winch brake worn or improperly adjusted | Uncontrolled lowering, a leading cause of davit fatalities |
| Wire falls corroded or unequal in length | Boat hangs off-level at launch, uneven load on the hooks |
| On-load release hook not maintained to maker's schedule | Accidental release under load or failure to release when needed |
| Limit switches out of adjustment | Winch drives into its end stops, damaging the wire or gearing |
What to look for in a supplier
- LSA Code type approval certificate for the specific davit and hook combination supplied
- Documented load test and dynamic hook test history, not just a delivery certificate
- Spare wire falls and hook parts held for the exact model, since falls are replaced on a condition and calendar basis, not run to failure
Treat every drill launch as a real test of the brake and hooks, not a formality — most davit failures are found in service, not on a survey report, because wear only shows up under load.