A system for controlling a propeller having a plurality of blades having a primary control system and a backup control system. The primary control system including a sensor responsive to a propeller state, and a controller connected to the sensor and to an electrohydraulic control actuator. The electrohydraulic control actuator is connected via a bypass valve to a hydraulic actuator that controls at least a blade angle of a blade of the propeller. The controller generating commands to the electrohydraulic control actuator based on at least the propeller state. The backup control system including a second controller, an electrohydraulic solenoid operably connected to the bypass valve. The backup control system is operable to hydraulically disable the primary control system via the bypass valve upon the occurrence of a selected condition, the second controller modulates the operation of the electrohydraulic solenoid to control the bypass actuator based on the propeller state.

A system for controlling a propeller having a plurality of blades having a primary control system and a backup control system. The primary control system including a sensor responsive to a propeller state, and a controller connected to the sensor and to an electrohydraulic control actuator. The electrohydraulic control actuator is connected via a bypass valve to a hydraulic actuator that controls at least a blade angle of a blade of the propeller. The controller generating commands to the electrohydraulic control actuator based on at least the propeller state. The backup control system including a second controller, an electrohydraulic solenoid operably connected to the bypass valve. The backup control system is operable to hydraulically disable the primary control system via the bypass valve upon the occurrence of a selected condition, the second controller modulates the operation of the electrohydraulic solenoid to control the bypass actuator based on the propeller state.

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.

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 dual-redundant propellor servo drive provides propellor control, and a dual-redundant mixture servo drive controls an air-fuel mixture. A first processor and a second processor are communicatively coupled with the dual-redundant propellor servo drive and the dual-redundant mixture servo drive and with each other to provide dual-redundant propellor and mixture control. The throttle control lever provides a single lever for pilot control of aircraft power, and the throttle control configuration is compatible with an auto-land capability.

To provide an unmanned aerial vehicle that eliminates or minimizes the laboriousness involved in optimal pitch adjustment of propellers while eliminating or minimizing complexity and instability in airframe structure and/or flight programs. This object is solved by an unmanned aerial vehicle that is provided with a plurality of rotors and that includes: a center frame that is a central portion of an airframe of the unmanned aerial vehicle; and a plurality of arms extending radially from the center frame in plan view. A plurality of motors that are driving sources of the respective rotors are provided in the center frame. The plurality of rotors are supported by the respective arms. Each arm of the arms has a hollow cylindrical structure. A motive power transmission member configured to transmit a driving force of each motor of the motors to the each rotor is provided in the each arm.

Systems, apparatuses, and methods for overcoming the disadvantages of current air transportation systems that might be used for regional travel by providing a more cost effective and convenient regional air transport system. In some embodiments, the inventive air transport system, operational methods, and associated aircraft include a highly efficient plug-in series hybrid-electric powertrain (specifically optimized for aircraft operating in regional ranges), a forward compatible, range-optimized aircraft design, enabling an earlier impact of electric-based air travel services as the overall transportation system and associated technologies are developed, and platforms for the semi-automated optimization and control of the powertrain, and for the semi-automated optimization of determining the flight path for a regional distance hybrid-electric aircraft flight.

Systems, apparatuses, and methods for overcoming the disadvantages of current air transportation systems that might be used for regional travel by providing a more cost effective and convenient regional air transport system. In some embodiments, the inventive air transport system, operational methods, and associated aircraft include a highly efficient plug-in series hybrid-electric powertrain (specifically optimized for aircraft operating in regional ranges), a forward compatible, range-optimized aircraft design, enabling an earlier impact of electric-based air travel services as the overall transportation system and associated technologies are developed, and platforms for the semi-automated optimization and control of the powertrain, and for the semi-automated optimization of determining the flight path for a regional distance hybrid-electric aircraft flight.

The present disclosure is directed to a method for controlling rotors of a rotorcraft system comprising the steps of: receiving air velocity data, first and second rotors rotational angular velocity data, external air temperature data and rotorcraft altitude data by the control module; calculating air velocity over the plurality of blades based on the received data using the control module; calculating, based on the calculated air velocity, if one or more retreating blades of one of the first and second counterrotating rotors are generating insufficient lift; and sending one or more actuation signals from the control module to the electric motor and/or actuators of the other of the first and second counterrotating rotors to maintain a predetermined amount of lift.

Methods and systems for operating an aircraft powerplant comprising an engine coupled to a variable-pitch propeller capable of generating forward and reverse thrust are described herein. A request to enable a mode for automated reverse thrust is received. Reverse thrust conditions are determined to have been met when the aircraft is on-ground, a blade angle of the propeller is below a blade angle threshold and a position of a power lever is at a selected idle region of the power lever. Reverse thrust of the propeller is triggered when the mode for automated reverse thrust is enabled and the reverse thrust conditions have been met.

Methods and systems for operating an aircraft powerplant comprising an engine coupled to a variable-pitch propeller capable of generating forward and reverse thrust are described herein. A request to enable a mode for automated reverse thrust is received. Reverse thrust conditions are determined to have been met when the aircraft is on-ground, a blade angle of the propeller is below a blade angle threshold and a position of a power lever is at a selected idle region of the power lever. Reverse thrust of the propeller is triggered when the mode for automated reverse thrust is enabled and the reverse thrust conditions have been met.