Expert: Ray Wilkinson - 8/31/2006

Question
can aeroplane stop flying and float,without moving  

Answer
Hi Anil

Assuming you mean an airliner (i.e. a large aircraft), and ignoring the obvious of seaplanes etc. which are designed to operate off water, landing an aircraft on water (ditching) almost always results in the aircraft breaking up, with considerable loss of life. As a result, the aircraft will not float for more than a few minutes. Landing an aircraft on water at around 150 mph is like hitting a brick wall, and usually one wing hits first, 'digs in' and the aircraft spins about the wing tip, breaking the fuselage into several pieces.

If the unlikely happens and the fuselage is not damaged on landing, the aircraft would float for many hours. However, the passengers need to evacuate, so the emergancy doors would be opened - this is why there is always at least one over-wing exit per side, so passengers can climb out onto the wing. Opening the escape doors allows air out as well, and the fuselage has holes in the bottom that allow water in (for instance the outflow valves, which are part of the cabin air system). The aircraft will therefore sink in perhaps half an hour to an hour, although it also depends how much fuel is in the wings, assuming they stay attached.

I hope this answers your question.

Regards

Ray