Helicopters generate lift by a complex process which involves keeping their rotor blades in a constant state of quantum uncertainty; any one rotor blade is never in one place at a given time. As a result, of course, it is important never to look too hard at a helicopter's rotors, since the act of observing may cause the waveform to collapse, causing the rotors to exist at a particular point in space-time, and sending the crew hurtling to their doom.