Would this work to raise a boat that had sunk?

[MissPrettyFeet]

It's in maybe 20 ft of water. I was thinking about connecting a rope on the bow eye of the sunk boat, then trying to pull it up with another boat. Would that cause it to surface as it started to move forward? The sunk boat weighs about 1100lb, the tow boat weighs about 2000lb. If it were to surface, could someone bail water out of it while it was moving, so it would float on its own? If this would be too dangerous, then what would be an easy way to bring it to the surface?

 

[Steve]

That will not work.... but i've raised many boats. You can dive down to it, right??? First, get you four empty 55 gallon drums..... and drill a 1" hole on one side, anywhere near the drum's middle. Above that hole near the top, and below the hole near the bottom, drill one more hole, in line, with the middle hole, all 1" wide. Now, get you some 5/8th's rope, and tie a tight loop thru the top and bottom hole, but not the center one. Next, you cut your rope into two pieces, 10' long, and put a 1/2 quick link (made for chain) on each end. Now, get a portable air compressor. You dive down, and put your two ropes underneath the boat, one on each end. Next you sink your drums to the bottom by the boat, and when ready, connect one drum to each end of rope, with your quick links. The idea is then to take your air hose, turn it on a very low setting, and fill each drum with air..... evenly. I've raised many boats up to 28' with this method..... once near the top, you'll need a pump or two. Good luck,.

 

[john]

Here's an idea:
Since it is underwater it will require much less power to lift it. If you had 2 boats (larger than the sunken one) and could raise it by hand in between them, you might be able to drop in a bilge pump or 2 or 3 and get it high enough to take it to shallow water to finish bailing or pumping. You'll want to use straps under the hull to bring it up level. I would buy 2-20' nylon tow straps and attach lines to them to bring up the boat. This is about the cheapest easiest way I could think of without buying a lot of expensive equipment of a lot of details and set-up time.
If you have a compressor, buy tractor tire inner-tubes to inflate inside the boat. 4-5 would probably get it to the surface Maybe less.

Good luck!

 

[seattlesailor2000]

if you are going to hire a diver to go underwater to the boat, then the best way to re-float the boat would be for the diver to carry an extra air tank and attach floatation bladders to the boat and inflate them. large truck inner tubes could also work. the bladders/inner-tubes will support the boat on the surface while you bail the boat.

more info

http://www.scubaboard.com/forums/do-yourself-diy/41616-need-advice-raising-half-sunken-boat.html

i would not suggest using you first plan. if you could pull the boat to the surface, towing a swamped boat is very difficult (without floatation) there is nothing to keep it from submersing again.

what you are attempting could be very dangerous, remember to go slow and stay safe.

hope this helps