In reading about various theories of what happened to flight MH370, there's a lot of discussion about it possibly crashing into the ocean, breaking up, and pieces of the aircraft floating hundreds of miles away.
Is it generally expected that large pieces of an aircraft will float fairly well? E.g. in the linked article, there's a picture of 4 guys carrying what looks like a big chunk of wing. How did that float?
My assumption would have been that that chunk was hollow aluminum fuselage, maybe with some electronics and hydraulics inside, and maybe a portion of a gas tank. I don't get how it would float unless it got lucky and a subsection of gas tank that was empty and did not get pierced during the breakup landed with its inlet/outlet pointing up.