In this example, the relative airspeed changes by a factor of two during every rotation. Lift is a function of the angle of the airfoil to the relative airflow combined with the speed of the air. To counteract this change in lift, which would normally pitch the aircraft, the rotor system has to dynamically adjust the angle of the airfoils to ensure they generate a steady amount of lift throughout their motion. This adjustment is in addition to any that is being applied deliberately to manoeuvre. Since every control system has some mechanical limit, as the aircraft speeds up it loses manoeuvrability.