Patent attributes
A propeller blade pitch control system includes a propeller hub for mounting at least one propeller blade, and a propeller shaft which rotates about an axis to rotationally drive the propeller hub. A pitch change yoke located within the propeller hub is configured to change a pitch of the at least one propeller blade in response to hydraulic fluid flow to a pitch change actuator. A propeller gearbox includes a first, rear end and a second, forward end located between the first, rear end and the pitch change yoke, and is configured to apply torque to the propeller hub. A hydraulic transfer bearing located between the first, rear end and the second, forward end of the propeller gearbox is operable to selectively permit a flow of hydraulic fluid from at least one hydraulic flow controller to the pitch change actuator.
