Patent ID: 9511856
Filing Date: 2016-12-06
CPC Classification: B64C

Claim Text:
1. For use with a helicopter including a rotor system having a main rotor with an adjustable pitch that is controlled at least in part by a pilot using a collective control, an apparatus comprising: an actuator arrangement including a motor having an output shaft for rotation to change the adjustable pitch by exerting an actuation force and a clutch supported by the output shaft and in operative communication with the collective control such that the clutch slips relative to the output shaft to allow the pilot to overcome said actuation force using the collective control but otherwise the clutch co-rotates with the motor shaft to bias the adjustable pitch toward a minimum collective pitch position; and a control arrangement that is configured to receive a signal that is indicative of a low rotor RPM condition and to respond to said signal by activating the actuator arrangement to exert the actuation force.