First of all, is there a default keyboard command for raising/lowering floats? and under what conditions (if any) will they not work? - I guess that's two questions in one

Secondly, when I land on the water with a couple of amphibious planes and turn off the engines, then restart them, the plane won't move; it's like I dropped a boat anchor; the engines at full throttle but no forward motion, and I have to quit the flight. Any suggestions?
Cheers!
