after you get the UAV to land, the engine won't turn off, it you do it manually, once you release controls, the engine will turn back on then the uav will try to take off again, you have to wedge in on the ground to get it to even stop, and the engine is still going.
The hover UAV also won't turn off it's engines or turn them back on when you release controls, but it won't take off after. {F21456}