Boat Sinking?????

[Grant]

Originally Posted by sa meredith

Secondcurve...
I might be wrong, but I believe they attach huge airbags to the boat, that somehow instantly inflate underwater, and they actually float the boat to the surface. Someone at Paugus Bay Marina told me that is how some construction equipment was recovered from the bottom a few years back.
Rattlesnake Gal...some photos of this process would be great if you have the time. Maybe????

Lift bag or bags, attached to the boat by divers, then inflated from a cylinder. Once on the surface, it can be towed to shallow water and fully raised. Given the size of the boat and the depth, I'd imagine it would require a large bag and a few divers. The visibility at that depth in Winnipesaukee is minimal and the temp is always in the 40s.

Here's a good page that describes their use.

And here's a photo a multiple large bags being used to bring up a freight train car.



I've only used a small one (~50 pounds of lift) to help bring comparatively small items to the surface. I stopped into Dive Winnipesaukee in February a few years ago, and Tom had a bunch of big ones out on the floor drying. He had spent the day working to raise a pickup truck with a plow that had gone through the ice in Tuftonboro (I believe there were photos on this site). The problem with that recovery was the thin ice surrounding the hole.

Now there's a tough day's work.

I'd love to watch them raise a 24-foot boat, and would be interested to know how much air to add at 100+ feet (as the air expands during ascent).