Deep salvage

[bell47]

Don't get exicted...it's not treasure. We are thinking about raising a boat(38footer) from about 200fsw. We've raised lots of boats, and done a fair amount of technical diving but never raised a boat from this deep. We are thinking about using open bottom lift bags, and pontoon/pillow bags with a calculated amount of air so they will be just full as they hit the surface. All bag inflation will be done with NO divers in the water because it's gonna come up really fast once it starts up. Anyone ever raised a boat ( or any other 20,000 object) from this deep? Open to new ideas. The pontoons and pillow bags will hold it up if the open bottom bags "spill" on hitting the surface. I know exactly what will float this boat....I've raised it once before...LOL. Bring on the ideas.

OH yeah, I forgot to say our work barge could lift it from the bottom but might not be as much fun as lift bags from this deep, but we do have that option.

[stevemc]

If you have enough lift bags, you could do it. You could also use empty 55 gallon drums. The diver would have to work pretty quick filling at 200'. Have a couple pumps ready at the surface. I find a 3" pump with a 6 HP motor works quick. Once its up, you really have to get the water out fast, or it will go back down. When you start getting the water out, and it starts floating and it goes pretty quick then. You just fill them, and they will lift, the excess comes out. You dont have to get it right. They will take right off though, so be ready. Make sure you arent tangled in the ropes.

[bell47]

Yeah, we have raised a few boats using lift bags, just not from this deep. We don't need drums, we have quite a few bags. Should be interesting. Not quite sure if we're gonna do it yet, just doing a little preliminary planning.

[allen_idaho]

You could try filling the boat with foam before you lift it. It would make it a bit more buoyant and easier to keep on the surface. But the downside here is the cost and the need to remove the foam when you are done.

It might not be worth it for such a small craft but I thought I'd throw it out there anyway.

[Curtis]

On the foam...if you used a thicker mil plastic to line the inside before the foam goes in there would be many hours saved in cleanup when removing the foam.

[FISHEYE]

A friend of mine raised 3 ww2 era PT boats from 60 foot using waterbeds(not the waveless kind).He stuffed them inside the boats and filled them with o2 from the largest o2 welding tanks he could get.Once on the surface he pumped out the remaining water.

[capthawk]

and has slept well since on the leftover equipment.... ??

[bell47]

Well we actually did a deep water salvage the other day. We brought a truck up from the bottom of a quarry in 220' feet of water. Wanna know what we used? It wasn't drums, liftbags, ping pong balls, foam or waterbeds... we used a big crane and it worked like a charm! LOL Thanks for all the very interesting ideas on salvage work but we do have real liftbags. Still thinking about that boat, but don't know if it's worth the effort. Thanks again guys, anymore ideas let me know.

[AUVnav]

Not sure if this has been lifted yet. At that depth, you would have to be really careful with lift bags. Once the boat starts to move up from the bottom, just as with your BC, they will expand, and the boat can begin a rapid ascent, making a bad problem a really bad problem.

Good luck!

[mohicanjoe]

Recommend the use of inner tubes in tandom- connected with heavy line. Calculate volumetrics of vessel, add in water volume and salinity, calculate silt suction if applicable. Calculate volume of tubes, water density, and how many sandwitches you will need while filling the tubes, slowly in sequence, just like lift bags. Works for us at 30 to 350 feet everytime, if your not into lift bags....

tim 941.488.2257 if you call, we haul it for you...you buy the air.....

[kai_gold]

Nevermind. This is a really old thread that resurfaced.