Inflatables To Raise Ship Wrecks

[joko]

years ago a saw something about raising ships by putting huge inflatables inside them.
i think theyre made of kevlar balloons.

there were also vague plans to put these into all ships to prevent them from sinking in the first place.

that sounds like a brilliant idea - how many lives & ships would be saved if the wrecks could stay afloat until rescue comes?

but ive never heard of it happening - does it? has it?

is there a reason this kind of things has not become standard?

i realise its a massive undertaking to rig ships with this kind of equipment & perhaps to have it automatically trigger.
it'd require a lot of redesign of standard features on a ship, places to store the inflatable material, trigger switches, air funnels etc to fill them - especially for enormous cruise ships etc.
obviously itd be a huge cost- but surely its worth it?
the basic tech already exists and is used by salvage ops to raise shipwrecks, it'd need some reworking.

is there some reason that im unaware of?
i havent looked into it a great deal, because i dont really know what to search for, and so far it just brings up info about salvage ops raising wrecks.

anyone know anything?

im just curious really

thanks :)

[Buenchico]

Some info here:
https://www.maritimeprofessional.com/blogs/post/5-most-common-marine-salvage-airbags-15480

[joko]

thanks buen.
seems like it'd be feasible, the bags probably wouldnt need as much space as i was imagining, or all that much space for air pumps.
The really thin version sounds best as its less room and weight, but they only need to keep the vessel afloat, not try to raise it from the ocean floor.
lots of smaller pillow bags, rather than the massive ones, with an instant filling mechanism - like the ones they have on inflatable life jackets & life rafts or even car airbags, because if one got damaged, there'd still be loads of others to keep the vessel afloat.

Im sure i read years ago that the power of air against water is surprisingly 'strong', stronger than you'd imagine and it takes a lot to submerge something airtight & keep it down.

i get why salvage people would prefer them not to be common place though, :D

i have no idea why ive been thinking about this, i have no connection whatsoever to ships or the ocean etc, haha.

[jno]

long ago a Dane salvaged a wrecked ship by pumping expandable polystyrene foam balls into it.

He applied for a patent - but didn't get it because the method had already been used in a Donald Duck comic

https://en.wikipedia.org/wiki/The_Sunken_Yacht

[johnk]

A ship needs to carry as much cargo as possible, the space needed for a flotation device would leave very little room for cargo and would not be a good investment and so would never be built.

[Peter Pedant]

phew long q
few answers

does it? has it? - Yes. Engineer saw a cartoon ( no really ) where mickey loo-loo saw a sunk ship and filled it full of ping pong balls to refloat it. And he thought - that is a good idea

Has it been used ? Yup

Not sure if it has been used in a pre sunk ship - where would you put the cargo?

er - what else - why dont they use it now?
er - - the answer would be.... it is a salvage expense and the other ways are cheaper. and the really bad cases where it could be used, the salvage is not worth it - - - would be my guess

( DOI used to hang around alot with engineers)

[Peter Pedant]

jno n I thinking alike
the patent was refused NOT because Donald Duck had done it
but because - the idea was not new and was already in the public domain

thought I might clear that one up

[Peter Pedant]

//I get why salvage people would prefer them not to be common place though, :D //

andy warhol rule - they'll do it if it pays - ( leddy of the night rule too). Unsalvageable in these cases means not worf it. get it wrong and you go out of business

they do it because of the loo-loo involved. When they come across a archeological wreck you can see why the poncey ivory tower archeologists go off their trolley.

[CrapAtCryptics]

Well it worked in Raise the Titanic so why not.