Systems and methods for controlling a variable-pitch propeller of an aircraft are provided. A method for controlling the variable-pitch propeller includes using a feedback controller, operating the variable-pitch propeller at a current operating condition including a current rotational speed, determining a speed error between the current rotational speed of the variable-pitch propeller and a set point rotational speed for the variable-pitch propeller, determining a gain for the feedback controller based on a power coefficient and an advance ratio of the variable-pitch propeller. Using the feedback controller, a propeller pitch command is determined based on the speed error and using the gain. The pitch of the variable-pitch propeller is adjusted according to the propeller pitch command to reduce the speed error.

Freezing of an electrical component of a VTOL rotor is prevented. The aircraft 100 includes a fuselage 12, a VTOL rotor 20 including one or more blades 23 that is supported on the boom 18 to be spaced apart from the fuselage for generating thrust in a vertical direction during take-off and landing, a motor 21 that is stored in the boom and is configured to cause the one or more blades to rotate, and an inverter 22 for controlling the motor, a detection unit 80 configured to detect a temperature of at least one apparatus of the motor or the inverter, and a control unit 99 configured to run the at least one apparatus based on a thrust request for a plurality of VTOL rotors and a detection result of the temperature.

An apparatus for controlling a tilt rotor is provided. The apparatus includes a thrust command generator configured to generate a first collective pitch angle based on a throttle command, a rotation speed compensator configured to generate a compensation value based on a rotation speed of the motor, a compensation weight generator configured to generate weight values according to a flight speed, a collective pitch angle command generator configured to generate a collective pitch angle adjustment command of the rotor blade of the motor, based on the first collective pitch angle and a first compensation value being obtained by multiplying the compensation value by a preset conversion ratio and a first weight value, and a motor controller configured to generate a motor control command based on a second compensation value being obtained by multiplying the compensation value by a second weight value and the first collective pitch angle.

The method can include operating the hybrid aircraft power plant in a first mode of operation in which a plurality of controllable parameters including a fuel flow to the thermal engine and an electric power to the electric motor has a first set of values corresponding to a first power output; receiving a requested power output; determining a second set of values of the one or more of the controllable parameters to bring first power output to the requested power output; determining whether said second set of values poses a risk of undesired clutch behavior; and when the second set of values poses the risk, modulating the second set of values to avoid the risk and setting the plurality of controllable parameters to the modulated second set of values.

A propeller propulsion system includes: a prime mover having at least one spool, a propeller arranged to be driven by the spool, a pitch adjustment subsystem comprising an electronic control unit and an electronic protection unit, a prime mover speed sensor arranged to detect a rotation speed of the spool; and an additional speed sensor arranged to detect the rotation speed of the spool or arranged to detect a rotation speed of the propeller. A first of the electronic control unit and the electronic protection unit is arranged to use an output from the prime mover speed sensor to determine the rotation speed of the propeller; and a second of the electronic control unit and the electronic protection unit is arranged to use an output from the additional speed sensor to determine the rotation speed of the propeller.

A method of operating a propeller system for an aircraft. The method includes: receiving propeller speed information, the propeller speed information indicating propeller speed; receiving a target propeller speed; performing a propeller speed threshold adjustment process, the propeller speed threshold adjustment process comprising adjusting a propeller speed threshold as a function of the target propeller speed; comparing the propeller speed to the propeller speed threshold; and in response to propeller speed exceeding the propeller speed threshold, performing an overspeed protection process.

The method can include operating the hybrid aircraft power plant in a first mode of operation in which a plurality of controllable parameters including a fuel flow to the thermal engine and an electric power to the electric motor has a first set of values corresponding to a first power output; receiving a requested power output; determining a second set of values of the one or more of the controllable parameters to bring first power output to the requested power output; determining whether said second set of values poses a risk of undesired clutch behavior; and when the second set of values poses the risk, modulating the second set of values to avoid the risk and setting the plurality of controllable parameters to the modulated second set of values.

A method and control system for controlling the thrust of an aircraft. A thrust request is input into a controller and the controller determines throttle, governor, and RPM setpoints to meet the input thrust request. The controller can determine minimum and maximum available thrust limits of the engine and can modify any of the setpoints if any setpoint violates the available thrust limit.

An energy recovery system and method for an aircraft having propellers. Specifically, the system and a method recover energy during the descent phase by setting the aircraft engines in propulsive mode or in windmill mode as needed. In windmill mode, the wind drives the propellers to generate electrical energy which may be stored. A pitch angle of the blade of the propellers may be changed.

A method of performing health monitoring for an aircraft having a variable pitch propeller system. The method includes: receiving aircraft flight information; performing a virtual pitch calculation to determine a virtual propeller pitch or virtual blade angle from the aircraft flight information; receiving a measured propeller pitch or blade angle from at least one physical sensor associated with the propeller; and using the virtual propeller pitch or virtual blade angle and the measured propeller pitch or blade angle to perform a health monitoring process to determine a health condition of at least one component of the aircraft, wherein the at least one component is distinct from the blades.