Rescue Boats and Survival Crafts.

Rescue Boats and Survival Crafts.

A rescue boat is a boat  designed to rescue persons in distress and marshal survival craft. A Survival Craft is a craft capable of  sustaining the lives of persons in distress  from the time of abandoning the ship. Passenger ships of 500 tonnes gross and over shall carry at least one rescue boat which complies with the regulations, on either side of the ship. Passenger ships of less than 500 tonnes gross shall carry at least one rescue boat which complies with the regulations.

Cargo ships shall carry at least one rescue boat which complies with the regulations. A lifeboat may be accepted as a rescue boat, provided that it complies with the requirements for rescue boats. If the rescue boat carried is a lifeboat it may be included in the aggregate capacity, for cargo ships less than 85 m in length. This is provided that the life raft capacity on either side of the vessel is at least 150 per cent of the total number of persons on board.

Similarly for passenger ships of less than 500 tonnes gross, and where the total number of persons on board is less than 200, if the rescue boat is also a lifeboat, then it may be included in the aggregate capacity. This is provided that the life raft capacity on either side of the ship is at least 150 per cent of the total number of persons on board.

The regulations state that:

The number of lifeboats and rescue boats that are carried on passenger ships shall be sufficient to ensure that in providing for abandonment by the  total number of persons on board not more than six life rafts need be marshaled by each lifeboat or rescue boat. Typical offshore operation of an ‘A’ frame launching davit for operation with semi-rigid inflatable rescue boat  is shown below. The number of lifeboats and rescue boats that are carried on passenger ships engaged on short international voyages shall be sufficient to ensure that in providing for abandonment by the total number of persons on board not more than nine life rafts need be marshalled by each lifeboat or rescue boat.

Launching Arrangements for Rescue Boats

Launching Arrangements for Rescue Boats

Rescue boat arrangements shall be such that the rescue boat can be boarded and launched directly from the stowed position with the number of persons assigned to crew the rescue boat on board. If the rescue boat is also a lifeboat, and other lifeboats can be boarded and launched from an embarkation deck, the arrangements shall be such that the rescue boat can also be boarded and launched from the embarkation deck.

Every rescue boat launching device shall be fitted with a power winch motor of such capacity that the rescue boat can be raised from the water with its full complement of persons and equipment. It should be kept at a continuous state of readiness for launching in not more than five minutes and be stowed in a suitable position to allow launch and recovery.

General Requirements for Rescue Boats

1. Rescue boats may be either of rigid or inflated construction or a combination of both.
2. Not less than 3.8 m and not more than 8.5 m in length. Capable of carrying at least five seated persons and a person lying down.
3. Rescue boats, which are a combination of rigid and inflated construction, shall comply with the appropriate requirements of the regulations affecting rescue boats to the satisfaction of the Authority.
4. Unless the rescue boat has adequate sheer, it shall be provided with a bow cover extending for not less than 15 per cent of its length.
5. Rescue boats shall be capable of maneuvering at speeds up to 6 knots and maintaining that speed for a period of at least 4 hours.
6. Rescue boats shall have sufficient mobility and maneuverability  in a seaway to enable persons to be retrieved from the water, marshal life rafts and tow the largest life raft carried on the ship with its full complement of persons and equipment or its equivalent at a speed of at least 2 knots.
7. A rescue boat shall be fitted with an inboard engine or outboard motor. If it is fitted with an outboard motor, the rudder and the tiller may form part of the engine. Outboard engines with an approved fuel system may be fitted in rescue boats provided the fuel tanks are specially protected against fire and explosion.
8. Arrangements for towing shall be permanently fitted in rescue boats and shall be sufficiently strong to marshal or tow life rafts as required in 6 above.
9. Rescue boats shall be fitted with weather tight stowage for small items of rescue equipment.
Rescue boats should be constructed in a manner to provide adequate stability and with inherent strength to withstand launching. Its internal access should be such as to permit rapid boarding by individuals and also allow persons to be retrieved from the sea or brought aboard on stretchers. Acceptable propulsion and steering arrangements together with a release launching mechanism must be approved by the Authority.

Rescue Boat Equipment

1. Sufficient buoyant oars or paddles to make headway in calm seas. Thole pins, crutches or equivalent arrangements shall be provided for each oar. Thole pins or crutches shall be attached to the boat by lanyards or chains.
2. A buoyant bailer.
3. A binnacle containing an efficient compass which is luminous or provided with suitable means of illumination.
4. A sea anchor and tripping line with hawser of adequate strength, and not less than 10 m in length.
5. A painter of sufficient length and strength, attached to the release device complying with the regulations.
6. One buoyant line, not less than 50 m in length, of sufficient strength to tow a life raft as required by the regulations. to enable the forward painter to be released under tension.
 7. One waterproof electric torch suitable for morse  signalling, together with one spare set of batteries and one spare bulb in a waterproof container.
8. A whistle or equivalent sound signal.
9. A first aid outfit in a waterproof container capable of being closed tightly after use.
10. Two buoyant rescue quoits, attached to not less than 30 m of buoyant line.
11. A searchlight capable of effectively illuminating a light coloured object at night having a width of 18 m at a distance of 180 m for a total period of 6 hours and of working continuously for at least 3 hours.
12. An efficient radar reflector.
13. Thermal protective aids complying with the regulations and sufficient for 10 per cent of the number of persons the rescue boat is permitted to carry (a minimum of 2)

Additional Equipment Requirements for Rescue Boats
Every rigid rescue boat shall include with its normal equipment:
(a) a boat hook;
(b) a bucket;
(c) a knife or hatchet.
Every inflated rescue boat shall include with its normal equipment:
(a) a buoyant safety knife;
(b) 2 sponges;
(c) an efficient manually operated bellows or pump
(d) a repair kit in a suitable container, for repairing punctures;
(e) a safety boat hook.

Additional Requirements for Inflated Rescue Boats
Unlike hulls and rigid covers of lifeboats the inflated rescue boats  do not have to be fire retardant but they should be of sufficient strength and rigidity to withstand launch and recovery in the inflated condition when slung from its bridle or lifting hook (with full complement).  The strength should be such as to withstand four times the load of the total mass of persons and equipment and capable of withstanding exposure on an open deck of a ship at sea or 30 days afloat in all sea conditions.
They should be marked as for an ordinary lifeboat but carry in addition,a serial number, the maker’s name or trade mark, and the date of manufacture.  Underneath the bottom and on vulnerable places on the outside of the hull, in the inflated condition, rubbing strips shall also be provided to the satisfaction of the authority.

The buoyancy of inflated rescue boats shall be a single tube which is subdivided into at least five separate compartments of approximate equal volume, or two separate tubes neither of which exceed 60 per cent of the total volume. The tubes should be so arranged that in the event of any one of the  compartments becoming damaged, the intact compartments shall be capable of supporting the full complement. The buoyancy tubes when inflated, forming the boundary of the boat, shall provide a volume not less than 0.17m3 for each person the boat is permitted to carry. Each buoyancy compartment will be provided with a non-return valve for manual inflation and means should be provided for deflation. A safety relief valve will also be fitted if the Authority considers this a necessary requirement. If a transom stern is fitted, it should not be inset by more than 20 per cent of the boat’s length. Suitable patches shall be provided for securing painters fore and aft and securing of the becketed lifeline inside and outside the boat. The boat itself should be maintained at all times in the inflated condition.

Rescue Boat

Rescue Boat

A 6.4m Avon Sea rider operating at speed is an example of a semi-rigid, fast rescue boat (FRC) now carried by many vessels.  ( As shown in the Fig).
The rescue boat should be capable of recovering persons from the water and marshalling other survival craft.

Immersion Suit

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An immersion suit is a protective suit which reduces the body heat loss of a person wearing it in cold water. Passenger ships shall carry for each lifeboat on the ship at least three immersion suits which comply with the regulations. In addition a thermal protective aid must be provided for every other person who is to be accommodated in the lifeboat, who is not provided with an immersion suit.

These immersion suits and thermal protective aids need not be carried if:
(a) persons are to be accommodated in totally or partially enclosed Lifeboats, or (b) if the ship is constantly engaged on voyages in warm climates where in the opinion of the authority, thermal protective aids are unnecessary. With respect to the rescue boat of passenger and cargo ships, each person assigned to the crew of a rescue boat will be provided with an immersion suit of appropriate size, which complies with the regulations.

Cargo ships shall carry for each lifeboat on the ship at least three immersion suits which comply with the regulations, or, if the Authority considers it necessary and practicable, one immersion suit for every person on board the ship. However, in addition to immersion suits required for life rafts, lifeboats and rescue boats the vessel shall carry thermal protective aids for persons not provided with immersion suits. These immersion suits and thermal protective aids need not be required if the ship:(a) has totally enclosed boats on each side of the ship of such aggregate capacity as will accommodate the total number of persons aboard; or (b) has totally enclosed lifeboats capable of being launched by free fall over the stern of the ship of such aggregate capacity as will accommodate the total number of persons on board, launched directly from the stowed position, together with life rafts on each side of the ship of such aggregate capacity as will accommodate the total number of persons aboard; or (c) is constantly engaged on voyages in warm climates where in the opinion of the Authority immersion suits are unnecessary.

Cargo ships of less than 85 m length other than oil tankers, chemical tankers and gas carriers, shall carry immersion suits which comply with the regulations for every person on board unless the ship: (a) has davit launched life rafts; or (b) has life rafts served by equivalent approved appliances, capable of being used on both sides of the ship and which do not require entry into the water to board the life raft; or (c) is constantly engaged on voyages in warm climates where in the opinion of the Authority immersion suits are unnecessary. The immersion suits required to be carried by cargo vessels may be used to comply with the requirements for rescue boats.

Life rafts shall be provided with thermal protective aids which comply with the regulations, sufficient for 10 per cent of the number of persons the raft is permitted to carry or two whichever is greater. Lifeboats shall be provided with thermal protective aids which comply with the regulations, sufficient for 10 per cent of the number of persons the lifeboat is permitted to accommodate or two, whichever is the greater.

General Requirements for Immersion Suits

General Requirements for Immersion Suits

1.The immersion suit must be prepared with waterproof material such that (A)it can be donned in not more than 2 minutes without any assistance.
(B) does not provide support for firing or melting after continuing fire exposure wrapped for interval of 2 seconds
(C) covers the entire body except for the face. The hands should be cover except gloves are provided.
(D) Arrangements to minimize must be provide to reduce the air from outside of the tightening legs;
(E) Can  withstand after a jump not less than 4.5 m from height into water.
2. A dive suit with the regulations similar on rescue vests can be classified as lifeguards.
3. A diving suit should allow the person to use life jacket, if the suit should be used with a life jacket:
A) Jump from a vertical scale of at least 5 m in length; (B)Can perform normal tasks while giving up; (C) Withstand an inclination of not less than 4.5 m into the water without damage or the immersion or injury displacement;(D) swim a short distance through the water and on a rescue boat.
4. A diving suit is designed so that the buoyancy is intact without a life jacket, they must be equipped with a light and a whistle, Compliance with regulations BH.
5. If the diving suit is designed to be used with one Life jacket, wear life jacket on the diving suit.
Person wearing such a diving suit is able to wear a life jacket.

Performance Requirements

A diving suit material which does not have inherent insulation may be:
(A), A Suit which must be used in conjunction with warm clothing; B) designed such that when used together with clothing and life-jackets the suit is worn heat protection must continue after a jump, by the user in the provide water from a height of 4.5 m , To ensure that when worn for 1 hour in calm water, flows at a temperature, 5 ° C, the core temperature of the user's body does not drop more than 2 ° C, An immersion suit of natural insulation material when used alone or with a life jacket when the kit is to be worn with a life jacket to provide the user with insulation sufficient after a jump in water from a height of 4.5 m to ensure that the temperature of the support is not more than 2 ° C after a Period of 6 hours in still circulating water at a temperature between 0 and 2 ° C.

The dive suit is intended to allow the person to carry it with the hands, use a pen to record and write after being immersed in water, 5 ° C for a period of 1 hour.

Thermal protective Aid (TPA)

A bag or a combination of a water-impermeable material with low thermal conductivity. Thermal protective Aid (do not be confused with immersion suits)

1. Aids should be heat-resistant impermeable material, Thermal conductivity of not more than 0.25 W / (mK), and are constructed such that, Can be used when a person is surrounded by Convection and evaporation from bodies.
2. With heat protection:
A) covers the entire body of a person wearing a life jacket with the exception of the face. The hands should also be provided at least provided permanent gloves.

(B) is able to be easily unpacked and put without any help in a Life boat or a rescue boat.
(C) allows the user to remove the aid in water from no longer than 2 minutes, when the ability to swim affects.
3. The thermal protection function properly in an air temperature range of 30 ° C to 20 ° C Lifeboats equipment. A means to safely transfer a survival craft or rescue boat from its stowed position to the water.

General requirements for Life boats

The lifeboats must be constructed stable and full of every work of a serious and stable freeboard with sufficient stablity, with equipment with sufficient accuracy. The position of a the hull to be rigid, to protect the life even when fully loaded with the houses of the desirables.
2. Life boats shall have sufficient strength to:
(A) allow them to be lowered into the water, safe when loaded with its complement and complete equipment; B) is released and towed when the ship travels at a speed of 5 knots in calm water.
3. Hulls and rigid covers shall be fire-resistant or non-combustible.
4. The seats are installed in banks, banks or fixed chairs as small as possible in the life boat attached and designed the respectively the number of 100 kg.
5. Each life boat shall have a sufficient strength to withstand a load without permanent deformation after removal of the load: a) In the case of vessels with metal hulls, the total mass of the life boat shall be 1.25-fold when loaded with its full number of persons and devices , B) In the case of other boats, the double of the total mass of the life boat, when displayed as displayed. (Boaters should note that this requirement does not save the boot.)
6. The resistance of each life boat is fully loaded and provided with skids or mudguards, if at all, must be able to withstand a side impact against the ship's side with an impact speed of at least 3, 5 m / s and also a drop in the Water from a height of at least 3 m.
7. The vertical distance between the ground surface and the chamber or the upper cover 50 per cent of the ground surface shall be: (a) not less than 1,3 m for a life boat with up to nine or less b) not less than 1,7 m.

Standard Lifeboat Equipment

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1. Except for free fall lifeboats sufficient buoyant oars to make headway in calm seas. Thole pins, crutches or equivalent arrangement shall be provided for each oar provided. Pulling oars are normally between 3.05 and 4.26 m in length (10–14 ft), they are generally made of ash or elm wood, and stowed with their blades facing forward. A steering oar, which is no longer specified, if carried, is usually approximately (12 in.) 0.3 m longer than the pulling oars. Its blade faces aft and is usually coated in a distinctive colour. It is used extensively to provide additional leverage in order to steady the boat’s head when used in conjunction with the sea anchor.
2. Two boat hooks, to be left unlashed and ready for use in fending away from the ship’s side.
3. A buoyant bailer and two buckets. These are secured by lanyards to the structure of the boat. Buckets are usually of a 2 gallon size (9 l) and manufactured in galvanised iron or rubber, stowed either end of the boat.
4. A survival manual.
5. Two axes (hatchets) stowed one at each end of the boat. It is common practice to cover the metal head of the axe with a canvas protective cover to prevent the metal from pitting and corrosion.
6. A jack-knife to be kept attached to the boat by a lanyard. The blade normally incorporates a tin opener and screw driver, and a small hand spike is usually attached.
7. Two buoyant rescue quoits, attached to not less than 30 m of buoyant line.  These are normally stowed in the small gear locker.
8. Six doses of anti-seasickness medicine and one seasickness bag for each person the boat is permitted to accommodate.The medicine is normally in tablet form.
9. A manual pump (unless the lifeboat is automatically self-bailing). Usually fixed to the structure of the boat. It is fitted with an easily……removed cover to allow cleaning and the suction end contains a gauze filter to avoid blockage of the system.
10. A sea anchor of adequate size fitted with shock resistant hawser and a tripping line which provides a firm hand grip when wet. The strength of the hawser and the tripping line shall be adequate for all sea conditions.
11.. Four rocket parachute flares, which comply with the regulations.
12. Six hand flares (red) which comply with the regulations.
13. Two buoyant smoke floats (orange) which comply with the regulations.
14. One waterproof electric torch suitable for Morse signalling, together  with one spare set of batteries and one spare bulb in a waterproof container.
15. One whistle or equivalent sound signal. Normally of plastic construction of the non-pea design. This will allow its use in cold weather without discomfort to the user.
16. One daylight signalling mirror with instructions for its use for signalling
to ships and aircraft (see life raft equipment list for use).            
17. An efficient radar reflector, unless a survival craft radar transponder is stowed in the boat.
18. One copy of the life-saving signals table, prescribed by regulation V/16 on a waterproof card or in a waterproof container.
19. Two efficient painters of a length equal to not less than twice the distance from the stowage position of the lifeboat to the waterline in the lightest sea-going condition or 15 m whichever is the greater.  One painter attached to the release device, placed at the forward end  of the lifeboat, must be capable of being released when under tension.The other painter shall be firmly secured at or near the bow of the lifeboat ready for use.
20. A binnacle containing an efficient compass which is luminous or provided
with suitable means of illumination. In a totally enclosed boat the binnacle shall be permanently fitted at the steering position,in any other lifeboat, it shall be provided with suitable mounting arrangements.
When setting up a boat’s compass, the mariner should bear in mind that it must be visible to the coxwain and a fore and aft line may have to be set up between the stem and stern to provide reference for means of aligning the boat’s head to the lubber line.
21. Sufficient tools to allow minor adjustment to the engine and its accessories.
22. Portable fire extinguishing equipment suitable for extinguishing oil fires.
23. A searchlight, capable of effectively illuminating a light coloured object at night having a width of 18 m at a distance of 180 m for a total period of 6 hours and of working continuously for not less than a 3 hour period.
24. Thermal protective aids which comply with the regulations, in sufficient
number for 10 per cent of the total number of persons that the boat is permitted to carry, or two whichever is the greater.
25. A watertight receptacle containing a total of 3 litres of fresh water for each person the lifeboat is permitted to accommodate. 1 litre of this amount may be replaced by a de-salting apparatus capable of producing an equal amount of fresh water in two days.
26. A rustproof dipper with a lanyard, used for extracting fresh water from the containers.The lanyard should be long enough to reach the bottom of any water tank.
27. A rustproof graduated drinking vessel.
28. Three tin openers.
29. One set of fishing tackle.
30. A food ration is not less than 10,000 kJ for each person rescue boat to reside. These sections are stored in sealed packages and stored in an airtight container.
31. A First Aid Kit Sealed in a Sealed Housing
After use.
All items of equipment of the lifeboat, with the exception of the two boat hooks, should be secured by lashings or kept in storage lockers, or secured by brackets or other similar mounting arrangement. Considerable changes in standard equipment have taken place with the 1983 amendment to the SOLAS convention.

TOTALLY ENCLOSED SURVIVAL CRAFT/ LIFE BOAT

 TOTALLY ENCLOSED SURVIVAL CRAFT/ LIFE BOAT

These craft  are invariably made of glass-reinforced plastic (GRP).They have proved themselves in practice to be a worthwhile advance in the marine field of survival craft, especially with regard to heat-resistance and the exclusion of toxic fumes. These qualities are now statutory for parent vessels engaged on the tanker trades. The totally enclosed survival craft are self-righting even when fully laden. They contain their own internal air supply, together with a pump for providing an external water mantle to reduce fire hazards. Tests have shown that a comfortable temperature is maintained inside the craft when outside temperatures have exceeded 1150°C. This desirable quality has been achieved by high standards of fire-resistant resin in the glass fibre construction, in conjunction with the sprayed water mantle from the built-in nozzles about the exterior hull. These craft are popular not just in oil tankers but also in the offshore oil industry on rigs and platforms. When launching takes place, all hatches should be closed.The release gear may be operated from inside the craft, the risk of accident from floating blocks, which may occur with the conventional davit and open boat systems.

The craft are manufactured with varying carrying capacity and engine size. Normal speeds for such craft are about 6 knots.  Speeds can be increased by installing a larger engine but a loss in carrying  capacity would result. Requirements for Totally Enclosed Lifeboats/Survival crafts.
Every totally enclosed lifeboat shall be provided with a rigid enclosure. The enclosure shall be so arranged that:
1. It protects the occupants against heat and cold.
2. Access into the lifeboat is provided by hatches which can be closed to make the boat watertight.
3. Hatches are positioned so as to allow the launching and recovery operations to be performed without any occupant having to leave the enclosure.
4. Access hatches are capable of being opened and closed from both inside and outside and are equipped with means of holding them securely in the open positions.
5. It must be possible to row the lifeboat.
6. It is capable, when the lifeboat is in the capsized position with the hatches closed and without significant leakage, of supporting the entire mass of the lifeboat, including all equipment, machinery and its full complement of persons.           
7. It includes windows or translucent panels on both sides which admit
sufficient daylight to the inside of the lifeboat with the hatches closed to make artificial light unnecessary.
8. Its exterior is of a highly visible colour and its interior of a colour which does not cause discomfort to the occupants.
9. Handrails provide a secure handhold for persons moving about the exterior of the lifeboat and aid embarkation and disembarkation.
10. Persons have access to their seats from an entrance without having to climb over thwarts or other obstructions.
11. The occupants are protected from the effects of dangerous sub atmospheric pressures which might be created by the lifeboat’s engine.
Launching when Parent Vessel is Making Way
Cargo ships of 20,000 tons gross tonnage and upwards, should have lifeboats capable of being launched, where necessary utilising  painters, with the ship making headway at speeds up to 5 knots in calm water.
Release Mechanism
Every lifeboat to be lauched by a fall or falls shall be fitted with a release
mechanism which complies with the following:
(a) the mechanism shall be so arranged that all hooks release  simultaneously;
(b) mechanism shall have two release capabilities, namely,
(i) A normal release capability which will release the craft when waterborne or when there is no load on the hook.
(ii) An on-load release capability which will allow the release of the craft when load is on the hooks. This will be so arranged as to release the boat under any condition from no load with the boat in the water, to when a load of 1.1 times the total mass of the lifeboat (fully loaded) is acting on the hooks.The release mechanism should be adequately protected against accidental or premature
use.
(c) The release control should be clearly marked in a contrasting colour.
(d) The mechanism shall be designed with a safety factor of 6 based on the ultimate strength of materials used, assuming the mass of the boat is equally distributed between falls.
Painter Release
Every lifeboat shall be fitted with a release device to enable the forward
painter to be released when under tension.    

FREE FALL LIFEBOATS/SURVIVAL CRAFT

Free fall launching is defined as that method of launching a survival craft  whereby the craft with its complement of persons and equipment onboard is released and allowed to fall into the sea without any restraining apparatus.

Free Fall Lifeboats – Relevant Detail:

FREE FALL LIFEBOATS/SURVIVAL CRAFT

Capacity of Free Fall Lifeboats

The capacity of the boat will be determined by the number of persons that can be provided with a seat that will not interfere with the means of propulsion or the operation of any of the lifeboats equipment. Where a free fall lifeboat is carried for launching over the stern of the ship it must be of such aggregate capacity as will accommodate the total number of persons on board.

Performance

The free fall launched boat must be capable of being launched with its full complement, against a list of 20° and a trim of 10° on the parent vessel.  The craft must also be capable of being launched with the occupants positioned forward to cause the Centre of Gravity to be in the most forward  position. In a similar manner the boat must be capable of being launched with all persons aft, to cause the Centre of Gravity to be in the most aft position. Additionally, it must be capable of being launched with an operating crew only. The free fall height shall never exceed the free fall certification height.

Launching of Free fall life boats

The free fall lifeboat must be capable of being launched not only in the free fall mode but also by a secondary method by falls in conditions of unfavourable trim of upto 2° and list of up to 5°. If the power for operation of this secondary launch system is not gravity then the appliance must be connected to both the ships mains and the emergency power supply. The boat must also be capable of, and designed to float off from, its stowed position automatically. The boat must be capable of being launched with the full complement, within a period of 10 minutes from the time the abandon ship signal is given.

Lifeboat Falls 


Falls shall be constructed in corrosion resistant steel wire rope having rotation-resistant properties. An example in use is ‘Kilindo’ 18  7 or wirex 17  7.They are multistrand  wires which involves laying up round strands in the opposite direction to the previous layer of strands. Although termed a non-rotating rope, this is not strictly accurate because the separate layers of strands do twist, but each layer of strands turns in an opposing direction giving a balance effect when hoisting/lowering. Lifeboat falls shall be long enough for the survival craft to reach the water with the ship in its lightest seagoing condition, under unfavourable conditions of trim and with the ship listed not less than 20° either way.Maintenance.

Falls used in launching shall be turned ‘end for end’ at intervals of not more than 30 months and be renewed when necessary due to deterioration, or at intervals of not more than 5 years, which ever is the earlier.

Gravity Davits

Waterborne for taking on personnel.
The majority of gravity davits are fitted with tricing pendants, and the
boat must be equipped with means of bowsing in against the ship’s side to permit the removal of the pendants before embarking personnel.  The davits will successfully launch the boat against a 20° adverse list   in  the following way:

1. Two men should be ordered into the boat, to ship the plug and check that the painter is rigged in a correct manner. (Painter is passed inside
the fall and outside everything else, and secured well forward.)  Once all work inside the boat is complete, these two men should be seen to sit down in the boat and hold on to the lifelines.
2. The cox’n should check that the harbour pins are out.
3. The gripes should be slipped and any triggers checked to see that they are clear, the gripes being passed down to deck level clear of the boat.
4. A winchman must be ordered to stand by to lower the boat down to the embarkation deck.
5. Check that the overside is clear, then lower away by lifting the brake handle. The boat should descend from the davits until the tricing pendants take the boat’s weight and draw the boat into the ship’s side.
6. The bowsing in tackles should be rigged in such a manner that the
downhaul is secured in the boat with a round turn and two half hitches, on the bight about the linkage on the end of the falls.
7. Have the two men in the boat slip the tricing pendants once both ends of the boat are securely bowsed in.
8. The remainder of passengers and boats crew should now be embarked, and seated as low as possible in the boat.
9. Ease out on the bowsing in tackles and allow the boat to come away from the ship’s side, then let go the tackles from inside the boat and throw them clear, back towards the parent vessel.
10. Order the winchman to lower the boat with a run. Ship tiller.
11. Unless release gear is fitted to the boat, it is more practical to lower
the boat into a trough of a wave. As the crest of the wave brings the boat higher, this will allow the falls to become slack, which will in turn allow easy slipping from the lifting hooks. Once the falls are clear, the boat falls away from the ship’s side as the wave drops away.

Survival Craft, Launching and Recovery Arrangements
Launching appliances complying with the regulations shall be provided
for all survival craft except:
1. Survival craft that are boarded from a position on deck that is less than 4.5 m above the waterline in the lightest seagoing condition and that either: (a) have a mass not more than 185 kg; or (b) are stowed for Launching directly from the stowed position under unfavourable conditions of trim of up to 10° and with the ship listed not less than 20° either way.2. Survival craft having a mass of not more than 185 kg and which are
carried in excess of the survival craft for 200 per cent of the total number of persons on board the ship.
 Each appliance provided must be capable of the launching and recovery of the craft. Throughout any launch or recovery operation the operator of the appliance is able to observe the survival craft.During the preparation and launching operation, the survival craft, the
launching appliance and the water area to which the craft is being launched shall be adequately illuminated by lighting supplied from the emergency source of electrical power, required by the regulations. Preparation and handling of survival craft at one launch station shall not interfere with the handling of any other survival craft or rescue boat. The release mechanism used for similar survival craft shall only be of one type carried aboard the ship.

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# Various books, study material and other online sources has been refereed prior to writing this article but no part is copied or produced  from any of the source but explained same thing in better detailed way.

Author: Amit                                                                                      

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