It very far from certain that a ship without propulsion will just stay afloat for a while. Even big ships can disappear in a hurry if the weather's bad enough.

It very far from certain that a ship without propulsion will just stay afloat for a while. Even big ships can disappear in a hurry if the weather's bad enough. See for example the sinking of the Derbyshire. http://www.youtube.com/watch?v=9tN4xROtMjI http://www.youtube.com/watch?v=9tN4xROtMjI