Helicopter blade pitch may be varied collectively to change climb rate, and it may be varied cyclically for directional movement. Pitch horns may be used to change overall blade pitch collectively in response to translation of a swashplate, and cyclically in response to tilting of the swashplate.
A blade may be configured to vary its flight mechanics in real time. As a first example, a blade is split into segments, and pitch of the segments may be controlled to affect lift or speed. As a second example, a blade is equipped with a trailing edge flap near its inboard side. Angle of the flap is varied to affect lift or speed. As a third example, a continuous blade is twisted along its pitch axis to affect lift or speed.
A helicopter rotor includes a rotating hub for carrying two or more blades. Actuators for the flaps and blade segments include hydraulic or electromechanical components mounted in the hub. Hydraulic or electrical power is transmitted from a non-rotating frame to the actuators in the hub.