Help – We’re Sinking!

How Do You Fix A Hole In The Hull At Sea?

The chances that you’ll have a collision at sea and sustain a hole in you hull, are pretty remote.  But these things do happen and you’ll know the expression “stranger things have happened at sea”. So what do you do?

  1. Did you hear the collision – either the bump of another boat or the ominous scraping of rocks?
  2. Are your bilges filling up with water?
  3. Are your seacocks secure?

If the answer is “yes” to these questions it’s pretty likely that you have a hole in you hull.

  1. Send a Mayday signal before the water gets to the electronics.
  2. Instruct you crew to don their life jackets, get their grab bags and be ready to board the life-raft.

Remember – only get into the life raft if you have to step up into it – i.e. if you boat is actually sinking.

  1.  Try to find the leak and do something about it.

Some handy hints

  • If a hose has burst you may be able to close its seacock.
  • Start using the manual bilge pump in the cockpit and if it’s not already working switch on the automatic bilge pump.
  • Pull up the sole boards in the main fore-and-aft passage to expose the length of the bilges and discover if water is flowing in. Check the direction of the flow. This may help you to locate the hole or crack.
  • Empty the lockers until you find the hole. If the access is poor you may need to clear some of the joinery away with a hammer. Brutal – but necessary, if you want to stem the leak.
  • Slow the flow of the leak by moving your crew and gear to the opposite side of the boat. Even if the hole doesn’t clear the water it may still slow down the flow.
  • If you are close to shore - head for it, trying to avoid any jagged rocks. Intentional grounding on a beach or a bar is better than sinking.
  • Stay with your boat, as many will float capsized and make a bigger target for the lifeboat or helicopter. Climb aboard it if you can, to stave off exposure to the cold water.

Some temporary repairs to “buy you time”

Some quick fixes have been tested which do not do the job and can even make the hole worse. These include;

  • Tying a sail under the hull to cover the hole.
  • Using a life jacket wrapped in a towel to plug the hole and then firing the inflator.
  • Using an umbrella poked through the hole and then opening it. 
  • Using a towel in a garden refuse bag forced through the hole. The water pressure is supposed to force the item back against the hole.
  • Forcing a sail in a sail bag through the hole.

There are however some quick fixes which have been tested and do seem to work well enough to buy you enough time to do a “get you home” repair.

  • If you find a small hole or crack you may be able to jam it temporarily with a wad of clothing, a pillow, cushion, bedding or whatever is to hand. Press against it with your foot until someone can bring you something to wedge it in place, such as knives or fishing rod butts.
  • A piece of wooden board, or more effectively a piece of engine room hatch with sound-proofing sponge, can be pre-drilled, fed through with a line which is then inserted through the hole from the outside and clamped tightly with a G-clamp.
  • The most effective. There are such things as collision mats – expensive and difficult to find! Just as effective is a sheet of damp course membrane and four Strong Grips. If you prod it under the boat’s knuckle, the flat smooth material can be see-sawed into place and secured with the grips. This method has been proved to stop the flow of water almost completely. The disadvantage is that you will have needed the forethought to have brought the materials on board with you.

Again many “get you home” repairs have been tested and failed once the boat is underway. These are the most effective ones.

  • Use 2mm ply or thicker covered in grease and mastic and screwed over the hole. Drilling holes for screws into the hull is not easy but possible with patience and self-tapping screws will hold the board well.
  • The best repair is probably achieved by using a special underwater repair kit, the “Kollision Kit” £71 from Epoxy Solutions. It uses a two-pack bonding system to stick a polymath over the hole. This has to be braced in place for 5 minutes but does create a reasonably decent repair.

Neither of these is a fool proof cure. The holes may well start leaking again before you reach land, but they keep your boat afloat and may slow the leak enough to be able to use the bilges or even bail her by hand.

A little hole in your hull may not look much but it is estimated that a 5cm hole below the water line will leak 300 litres per minute. A 10 cm hole at the same depth will leak 1,100 litres per minute. Enough to sink a 30ft yacht in 12 minutes.

It’s worth being prepared and having a plan of action thought out in advance – JUST IN CASE!

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