A variable pitch propeller assembly operatively coupled with an engine and methods for controlling the pitch of a plurality of propeller blades thereof is provided. In one example aspect, the variable pitch propeller assembly includes features for combining overspeed, feathering, and reverse functionality in a single secondary control valve. The secondary control valve is operable to selectively allow a controlled amount of hydraulic fluid to flow to or from a pitch actuation assembly such that the pitch of the propeller blades can be adjusted to operate the variable pitch propeller assembly in one of a constant speed mode, a feather mode, and a reverse mode.

A variable pitch propeller assembly operatively coupled with an engine and methods for controlling the pitch of a plurality of propeller blades thereof is provided. In one example aspect, the variable pitch propeller assembly includes features for combining overspeed, feathering, and reverse functionality in a single secondary control valve. The secondary control valve is operable to selectively allow a controlled amount of hydraulic fluid to flow to or from a pitch actuation assembly such that the pitch of the propeller blades can be adjusted to operate the variable pitch propeller assembly in one of a constant speed mode, a feather mode, and a reverse mode.

A system is provided. The system includes a dual piston actuator and valves. The dual piston actuator includes a primary actuator and a protection actuator. The primary and protection actuators move to increase and decrease a pitch of propellers of an aircraft with respect to a supply of first and second mediums. The valves include a first check valve, a second check valve, and a third valve. The third valve operates between a first mode and a protection mode. The second medium is directed to the primary and protection actuators through the first and second check valves by the third valve when the third valve is operating in a protection mode.

A system is provided. The system includes a dual piston actuator and valves. The dual piston actuator includes a primary actuator and a protection actuator. The primary and protection actuators move to increase and decrease a pitch of propellers of an aircraft with respect to a supply of first and second mediums. The valves include a first check valve, a second check valve, and a third valve. The third valve operates between a first mode and a protection mode. The second medium is directed to the primary and protection actuators through the first and second check valves by the third valve when the third valve is operating in a protection mode.

A turbomachine module includes a rotor supporting variable pitch blades, and an inner annular shaft, a blade pitch control device, a device for feathering at least one blade comprising at least one gas generator placed between a body and a movable member. The control device and the feathering device are situated radially between the shaft and the blades, the movable member is coupled with the at least one blade and capable, under the action of the gas generated and/or released by the generator, of being moved into a reference position wherein it entails a feathered position to the at least one blade.

A method for controlling an aircraft propeller is provided that comprises obtaining a measurement of a speed of the propeller, comparing the propeller speed to a first threshold, responsive to determining that the propeller speed exceeds the speed threshold, outputting a valve control signal for opening a two-position solenoid valve coupled to the propeller, the two-position solenoid valve configured for controlling fluid flow to and from the propeller to control propeller blade angle, computing a rate of change of the propeller speed, comparing the rate of change of the propeller speed to a second threshold, and responsive to determining that the rate of change of the propeller speed is below the second threshold, outputting the valve control signal for closing the two-position solenoid valve. A system for controlling an aircraft propeller and an aircraft propeller control assembly are also provided.

A method for controlling an aircraft propeller is provided that comprises obtaining a measurement of a speed of the propeller, comparing the propeller speed to a first threshold, responsive to determining that the propeller speed exceeds the speed threshold, outputting a valve control signal for opening a two-position solenoid valve coupled to the propeller, the two-position solenoid valve configured for controlling fluid flow to and from the propeller to control propeller blade angle, computing a rate of change of the propeller speed, comparing the rate of change of the propeller speed to a second threshold, and responsive to determining that the rate of change of the propeller speed is below the second threshold, outputting the valve control signal for closing the two-position solenoid valve. A system for controlling an aircraft propeller and an aircraft propeller control assembly are also provided.

A propeller control system for controlling a blade pitch angle including: a propeller blade extending from a blade base, the propeller blade being configured to rotate around a longitudinal axis to generate thrust for the propeller blade and rotate around a pitch change axis to adjust the blade pitch angle, wherein the pitch change axis extends through a center point of the blade base; a trunnion pin operably connected to the blade base at a location offset from the center point; a yoke plate operably connected to the trunnion pin; an actuator configured to move the yoke plate linearly along the longitudinal axis to rotate the trunnion pin and the propeller blade around the pitch change axis; and a transfer tube operably connected to the yoke plate, the transfer tube being free to rotate around the longitudinal axis as the actuator moves the yoke plate linearly along the longitudinal axis.

A propeller control system for controlling a blade pitch angle including: a propeller blade extending from a blade base, the propeller blade being configured to rotate around a longitudinal axis to generate thrust for the propeller blade and rotate around a pitch change axis to adjust the blade pitch angle, wherein the pitch change axis extends through a center point of the blade base; a trunnion pin operably connected to the blade base at a location offset from the center point; a yoke plate operably connected to the trunnion pin; an actuator configured to move the yoke plate linearly along the longitudinal axis to rotate the trunnion pin and the propeller blade around the pitch change axis; and a transfer tube operably connected to the yoke plate, the transfer tube being free to rotate around the longitudinal axis as the actuator moves the yoke plate linearly along the longitudinal axis.

An exemplary spring-loaded link for an aircraft including a spring interposed between a first and a second rod, the spring, when compressed, urging the first rod and the second rod away from each other.