Abstract: A propeller control unit for an aircraft propulsion system including a propeller is provided. The propeller control unit includes an actuator, a pump, a flow regulator, a pressure sensor, and a controller. The actuator is configured to control a pitch of each of the propeller blades. The pump is configured to direct hydraulic fluid to the actuator. The flow regulator is in fluid communication with the pump and configured to control a hydraulic fluid pressure of the hydraulic fluid downstream of the pump. The pressure sensor is disposed downstream of the pump and upstream of the actuator. The pressure sensor is configured to measure the hydraulic fluid pressure and generate a hydraulic fluid pressure signal. The controller includes a processor in communication with a non-transitory memory storing instructions, which instructions when executed by the processor, cause the processor to monitor the hydraulic fluid pressure signal.

Abstract: A propeller blade angle control circuit for a turboprop engine includes a propeller control unit controlling a supply of oil to modify an angle of propeller blades, a pump located upstream of the propeller control unit and providing the supply of oil from an engine oil return system to the propeller control unit, and a flow regulator between the pump and the propeller control unit, the flow regulator modulating a supply of oil to the propeller control unit. A bypass, downstream of the pump in the propeller blade angle control circuit, has an inlet fluidly coupled to the pump. The bypass is operable between a closed position and an open position in which a portion of the oil supplied to the propeller control unit is diverted away from the propeller blade angle control circuit. The open position is engaged when an oil pressure reaches a predetermined threshold.

Abstract: The variable pitch propeller control system can have a source of adjustable, actuation hydraulic pressure, a feather valve openable to provide an actuation path of the actuation hydraulic pressure between the source and the actuator, and closeable to connect the actuator to a drain below the actuation hydraulic pressure and close the actuator path, and a bypass path parallel to the actuator path, the bypass path having a restricted flow area relative to a flow area of the actuator path.

Abstract: The variable pitch propeller control system can have a source of adjustable, actuation hydraulic pressure, a feather valve openable to provide an actuation path of the actuation hydraulic pressure between the source and the actuator, and closeable to connect the actuator to a drain below the actuation hydraulic pressure and close the actuator path, and a bypass path parallel to the actuator path, the bypass path having a restricted flow area relative to a flow area of the actuator path.

Abstract: Systems, devices, and methods for controlling a fuel supply for a turbine or other engine using direct and/or indirect indications of power output and optionally one or more secondary control parameters.

Abstract: Systems, devices, and methods for controlling a fuel supply for a turbine or other engine using direct and/or indirect indications of power output and optionally one or more secondary control parameters.

Abstract: Systems, devices, and methods for controlling a fuel supply for a turbine or other engine using direct and/or indirect indications of power output and optionally one or more secondary control parameters.

Abstract: Systems, devices, and methods for controlling a fuel supply for a turbine or other engine using direct and/or indirect indications of power output and optionally one or more secondary control parameters.

Abstract: Systems, devices, and methods for controlling a fuel supply for a turbine or other engine using direct and/or indirect indications of power output and optionally one or more secondary control parameters.

Abstract: Systems, devices, and methods for controlling a fuel supply for a turbine or other engine using direct and/or indirect indications of power output and optionally one or more secondary control parameters.

Abstract: Systems, devices, and methods for controlling a fuel supply for a turbine or other engine using direct and/or indirect indications of power output and optionally one or more secondary control parameters.

Abstract: Systems, devices, and methods for controlling a fuel supply for a turbine or other engine using direct and/or indirect indications of power output and optionally one or more secondary control parameters.