Patent attributes
The present invention relates to a device (10) for varying blade pitch of a rotary wing aircraft (50) having a main rotor (11) with a plurality of blades (12), each blade (12) including at least one main flap (13) fastened to the trailing edge of the blade (12). The angle of inclination of each flap (13) is controlled via a swashplate (20). The device (10) makes provision for electric actuators controlled by a flight control system (54) to be mounted in a stationary frame of reference for the purpose of moving and varying the angle of inclination of the non-rotary plate of the swashplate (20). The electric actuators provide primary flight control and also multi-cyclic control for the purpose of attenuating noise and vibration as generated in particular by the blades (12) and the rotor (11).