Definition of waiver. 1  1 : the act of intentionally relinquishing or abandoning a known right, claim, or privilege; also : the legal instrument evidencing such an act.
Roll, pitch and yaw. Roll, pitch and yaw are rotations along the natural axes of the helicopter (or any aircraft). A rolling movement is where the helicopter rotates along a line along its length using lateral cyclic inputs (aileron), eventually turning from right way up to inverted while maintaining the helicopter's heading.
Just like airplanes, helicopters also rely on aerodynamic principles to fly. The main rotor of a helicopter consists of several blades. Each blade acts as a type of wing, and when the rotor rotates the air flows past the blade and generates a lift force to keep the helicopter in the air.