Each launching appliance shall be so constructed that only a minimum amount of routine maintenance is necessary. All parts requiring regular maintenance by the ship’s crew shall be readily accessible and easily maintained. Each launching appliance shall, as far as practicable, remain effective under conditions of icing.
Each rescue boat launching appliance shall be fitted with a powered winch motor capable of raising the rescue boat from the water with its full rescue boat complement of persons and equipment at a rate of not less than 0.3 m/s.
The launching mechanism shall be so arranged that it may be actuated by one person from a position on the ship’s deck and, except for secondary launching appliances for free-fall lifeboats, from a position within the survival craft or rescue boat. When launched by a person on the deck, the survival craft or rescue boat shall be visible to that person.
The winch brakes of a launching appliance shall be of sufficient strength to withstand:
1. a static test with a proof load of not less than 1.5 times the maximum working load;
2. a dynamic test with a proof load of not less than 1.1 times the maximum working load at maximum lowering speed.
An efficient hand gear shall be provided for recovery of each survival craft and rescue boat.
Where davit armsare recovered by power, safety devices shall be fitted which will automatically cut off the power before the davit arms reach the stops in order to prevent overstressing the falls or davits, unless the motor is designed to prevent such overstressing.
The speed at which the fully loaded survival craft or rescue boat is lowered to the water shall not be less than that obtained
from the formula:
S = 0.4 + 0.02H
where S is the lowering speed in meters per second and H is the height in meters from the davit head to the waterline with the ship at the lightest sea-going condition.
The maximum lowering speed shall be established by the Administration having regard to the design of the survival craft or rescue boat.
The lowering speed of a fully equipped liferaft without persons onboard shall be to the satisfaction of the Administration. The lowering speed of other survival craft, fully equipped but without persons on board, shall be at least 70% of that required for survival craft or rescue boat.
Every free-fall launching appliance shall comply with the applicable requirements for survival craft or rescue boat, in addition, shall comply with:
1. to be constructed so as to prevent sparking and incendiary friction during the launching of the lifeboat.
2. be designed and arranged so that in its ready to launch position, the distance from the lowest point on the lifeboat it serves
to the water surface with the ship in its lightest seagoing condition does not exceed the lifeboat’s free-fall certification height.
3. be arranged so as to preclude accidental release of the lifeboat in its unattended stowed position.
4. The release mechanism shall be arranged so that at least two independent actions from inside the lifeboat are required in
order to launch the lifeboat.
5. Each launching appliance shall be provided with a secondary means to launch the lifeboat by falls.
6. The secondary means of launching shall be equipped with at least a single off-load capability to release the lifeboat.
Every liferaft launching appliance shall comply with the requirements for survivalcraft or rescue boat, except with regard to
embarkation in the stowed position, recovery of the loaded liferaft and that manual operation is permitted for turning out the
The launching appliance shall include an automatic release hook arranged so as to prevent premature release during lowering and shall release the liferaft when waterborne. The release hook shall include a capability to release the hook under load.
The on-load release control shall:
1. be clearly differentiated from the control which activates the automatic release function;
2. require at least two separate actions to operate;
3. with a load of 150 kg on the hook, require a force of at least 600 and not more than 700 N to release the load, or provide
equivalent adequate protection against inadvertent release of the hook;
4. be designed such that the crew members on deck can clearly observe when the release mechanism is properly and completely set.