A system and method for feathering an aircraft propeller are provided. A first feather solenoid and a second feather solenoid each comprising at least one solenoid coil and a solenoid valve coupled to the actuator and to the at least one solenoid coil are provided. At least one controller is configured to selectively energize and de-energize the at least one solenoid coil. The solenoid valve of the first feather solenoid is configured to be activated when the at least one solenoid coil of the first feather solenoid is energized and the solenoid valve of the second feather solenoid is configured to be activated when the at least one solenoid coil of the second feather solenoid is de-energized. The solenoid valve is configured to, when activated, modulate the supply of hydraulic fluid to an actuator for adjusting a blade pitch of the propeller towards a feather position.

A gas turbine engine including: a turbomachine having a compressor section, a combustion section, and a turbine section arranged in serial flow order; a fan defining a fan axis and comprising a plurality of fan blades rotatable about the fan axis; and a pitch change mechanism operable with the plurality of fan blades, the pitch change mechanism including a plurality of linkages, the plurality of linkages including a first linkage coupled to a first fan blade of the plurality of fan blades and a second linkage coupled to a second fan blade of the plurality of fan blades; and a non-uniform blade actuator system operable with one or more of the plurality of linkages to control a pitch of the first fan blade relative to a pitch of the second fan blade.

The rotary airfoil 100 defines a cross section and a span, wherein the cross section is a function of the point along the span (e.g., spanwise point) and defines an upper surface and a lower surface at each spanwise point. The rotary airfoil 100 also defines, at a cross section, a lift coefficient (C.sub.L) that is a function of the angle of attack at which the airfoil is rotated through the air. The system can optionally include: a rotor hub to mount the rotary airfoil, a tilt mechanism to pivot the rotary airfoil between a forward configuration and a hover configuration, and a pitching mechanism to change the angle of attack of the rotary airfoil 100.

The invention relates to a method for controlling a pitch angle of the vanes or blades of a propellant body of a turbine engine, comprising generating a pitch command (i.sub.final) according to a rotational speed of the propeller (XN.sub.mes) and a speed setpoint (XN.sub.cons), the method comprises a nominal regulating chain (13), wherein the pitch command is further generated according to a value of a pitch angle (mes) of the vanes or blades of the propellant body, and an off-nominal regulating chain (16), wherein the pitch command is generated independently of a value of a pitch angle of the vanes or blades of the propellant body.

A control system for an engine operatively coupled with a propeller and methods for controlling an engine operatively coupled with a propeller are provided. In one example aspect, the control system includes a controller and an electric propeller governor. The electric propeller governor includes a motor operatively coupled with a flyweight governor spring. The motor is communicatively coupled with the controller. The controller is operable to receive data indicative of the speed of the propeller, determine if the measured speed exceeds a propeller speed threshold, and if the threshold is exceeded, the controller is configured to change a propeller speed set point. Particularly, the controller can cause the motor to change the preload on the flyweight governor spring, which in turn causes adjustment of the propeller speed set point. In this way, propeller speed overshoot is prevented during fast acceleration of the engine.

An automatic aircraft powerplant control system includes a throttle servo for adjusting a throttle valve via a throttle control linkage. A throttle control lever provides a user input to the throttle servo, and a throttle controller controls the throttle servo for controlling a throttle valve. A propeller servo is provided for adjusting a propeller governor setting of an engine. A propeller control lever provides a user input to the propeller servo, and a propeller controller controls the propeller servo. A mixture control servo is configured for providing a mixture control output to the engine via a mixture control linkage for adjusting an air-fuel mixture. A mixture controller is configured for controlling the mixture control servo.

A device for controlling a propeller, having variable-pitch blades, of a turboprop engine, has a first hydromechanical device for controlling the pitch of the blades of the propeller and a second hydromechanical device for controlling the speed of rotation of the propeller. The device includes a single electromechanical actuator with a movable actuator member mechanically connected both to the first hydromechanical device for controlling the pitch, in order to manage the pitch setpoint, and to the second hydromechanical device for controlling the speed, in order to manage the speed setpoint.

A propeller control unit (PCU) for controlling pitch angles of blades of a propeller, has: a pitch angle actuator; a servo valve hydraulically connected to the pitch angle actuator and to a first hydraulic fluid source; and a feather valve having a body movable within a cavity, the feather valve having a first actuation port and a second actuation port both in fluid communication with the cavity, the body between the first actuation port and the second actuation port, the body being movable to selectively hydraulically connect the pitch angle actuator to the servo valve through the feather valve or to hydraulically connect the pitch angle actuator to a drain line through the feather valve, the first actuation port and the second actuation port hydraulically connected to a second hydraulic fluid source independent from the first hydraulic fluid source.

An aircraft blade assembly, including: a blade extending from a blade root to an opposite tip; and a heat exchanger disposed on at least a portion of a leading edge of the blade, the heat exchanger including: a first arcuate panel shaped to conform to the leading edge of the blade; and a second arcuate panel mated with the first arcuate panel; wherein at least one of the first and second arcuate panels includes a channel formed thereon to form a fluid passage between the first and second arcuate panels.

A method for protecting an electric propulsion system in response to occurrence of a fault. The method includes the step of activating short circuits in power switches of inverters in a motor controller to redirect current regenerated by a motor which is electrically coupled to the motor controller and mechanically coupled to a propeller. The method further includes feathering the propeller while the motor is regenerating current. The protection logic is designed to address different types of faults, including faults in the high-voltage direct-current bus, faults in the motor controller, and faults in the motor.