The top deck of the boat or ship rides on pillars but is only tied down by a catch similar to those on skis.

Should the ship or boat start to sink, all passengers can rush to find a spot on the top deck & hang on as they have been instructed that it will remain afloat & unpowered, but afloat long enough for a rescue. Long enough to be towed to the nearest port if neccessary.
-- Zimmy, Mar 13 2006

Carley float http://lean.bfi.org...e&thumb=bfi-00m-m7f
A Carley float in action [oneoffdave, Mar 14 2006]

What if the boat turns turtle?
sp. "buoyant", "detachable"
-- coprocephalous, Mar 14 2006


//Isn't this a lifeboat?// Carley float.
-- coprocephalous, Mar 14 2006


Depending on the size of the boat/ship and the sea stte this may be worse than being in separate lifeboats or on floats. Some form of hydrostatic release should be used or the first good wave to break green over the boat will take the roof off.
-- oneoffdave, Mar 14 2006


If the roof is held on by gravity, rough seas could make it move and while it may not come off the movement may cause damage to the rest of the boat.

If it is held on by a catch then this would have to be released which could cause a problem if the release fails.

Finally, what advantage does this have over lifeboats. It seams to create a 'all eggs in one basket' situation
-- miasere, Mar 14 2006


It begs the question, why not an insubmersible boat?
-- GutPunchLullabies, Mar 14 2006


Baked, RNLI (coastguard) boats are self-righting if they are capsized.
-- miasere, Mar 14 2006


I will remind you that boats were formerly made entirely of insubmersible and detachable materials (i.e., wood). People still went down with their ships.

The boat itself has to be insubmersible, or you get sucked down in its wake when the boat sinks. (This is why you are advised to swim well away from a sinking ship when it's going down.)
-- DrCurry, Mar 14 2006


So, you're basically putting a boat with no ballast on top of a boat. Or within a boat. Either way, you're building a liferaft, just on a grand scale.
-- shapu, Mar 14 2006



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