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.
The rudder is a fundamental control surface which is typically controlled by pedals rather than at the stick. It is the primary means of controlling yawâthe rotation of an airplane about its vertical axis. The rudder may also be called upon to counter-act the adverse yaw produced by the roll-control surfaces. If rudder is continuously applied in level flight the aircraft will yaw initially in the direction of the applied rudder â the primary effect of rudder. After a few seconds the aircraft will tend to bank in the direction of yaw.