content: This isn't as black and white as the comments here make it seem. You are right, there are conditions in which a person or buoyant object could be sucked/dragged/fall to the bottom, however for this to happen the person/object would have to be in a bubble following the sinking object down. The conditions under which this happens may not be possible to achieve with a ship that starts on the surface as they will start sinking as soon as their buoyant force is lower than their mass, which means that it will start sinking slowly. All of that said, such a situation may be possible with a sinking ship, but may not be unless there is evidence either way that I don't know about. The mythbusters tested with one boat, hardly an exhaustive experiment (like they say, they stand by their methods, not their results).