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LOWERING A LIFEBOAT

The crew should be wearing life-jackets. The plug must be checked and fenders rigged over the inboard side. The boat-rope should preferably be passed as before to prevent surging, together with a painter, which must be kept tight. No one should stand between the falls and the boat ends. All crew members should grasp the lifelines, in addition to working the boat-rope if necessary.

The after block is cast-off first in a tideway to prevent the boat from broaching to. In a heavy sea the boat may be lowered on to a wave crest. As she slides into the succeeding trough, her falls are automatically overhauled (slacked) by the boat's weight. On rising to the next crest they are amply slack for rapid unhooking.

The painter should be kept tight in order to keep the boat fore-and-aft when launched. If the ship is making way, or if a stream is running down from ahead, a tight painter enables the boat to be sheered clear using her rudder. It also means that as soon as the boat is launched, no matter whether the ship is making way or a stream is running, the boat is virtually towed alongside and is kept vertically below the davit heads, facilitating unhooking.

On gravity davits a chain pendant is secured to the lower blocks by means of a patent slip. The other end is shackled to a point roughly two-thirds of the way up the davit. As the boat is lowered from the davit heads, the pendant tightens & the boat swings in to the embarkation deck-level, virtually on a union purchase.

If this pendant is later slipped, when the boat is ready for further lowering, the lifeboat will swing violently outboard as the fall seeks the vertical. This had been the cause of many serious accidents for the swing is sufficiently sudden & rapid to hurl a crew member over the side. Again, these accidents are prevented if the lifelines are held and the crew keep low down in the boat.

Once the boat has been triced in to the ship's side by these pendants, a length of 24-mm manila rope, provided for the purpose, is passed between the boat sheets & the cleat on the lower davit body/ The two or three parts are then held taut in the hands by gripping them together. The chain pendant may now easily be slipped, the manila jerks slightly as it grows bar-tight, and the boat is ready for easing out fore & aft on both manilas. A better arrangement is to use two small tackles and ease the boat out on these.

When time permits both of these remedies may be dispensed with: once a boat is ready for lowering to the water, moves away from the ship's side & the pendant grows slack. The latter is cast off & the boat launched in the normal way. One advantage, however of passing the tricing lines or tackles is that they act as preventers in case the chain pendant should part.

TO PURCHASE

 

TO HANDS
Lowering turns on staghorn bollard.

 

Some davits fitted with fiber rope falls provide for the boat to be lowered by hand control. A stag's head bollard is usually provided in way of each davit. A suitable method of passing the fall around such a bollard is shown in Fig 1, where it is rigged ready for lowering.



 

1 What should all crew members do before lowering a lifeboat?

2 Where is a chain pendant secured?

3 Where is other end shackled to?

 


Date: 2015-01-11; view: 1489


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