A rotor system comprising a hinge coupled between a rotor blade and a hub, where the hinge comprises a pivot that is angled relative to a rotor axis of rotation to enable pitch of the rotor blade to change when the rotor blade experiences lag.

A rotor system comprising a hinge coupled between a rotor blade and a hub, where the hinge comprises a pivot that is angled relative to a rotor axis of rotation to enable pitch of the rotor blade to change when the rotor blade experiences lag.

A system and method for protecting a rotorcraft from entering a vortex ring state, the method including monitoring a vertical speed of a rotorcraft, comparing the vertical speed to a vertical speed safety threshold, and performing vortex ring state (VRS) avoidance in response to the vertical speed exceeding the vertical speed safety threshold. The performing the VRS avoidance includes determining a power margin available from one or more engines of the rotorcraft, limiting the vertical speed of the rotorcraft in response to the power margin exceeding a threshold, and increasing a forward airspeed of the rotorcraft in response to the power margin not exceeding the threshold.

A system and method for protecting a rotorcraft from entering a vortex ring state, the method including monitoring a vertical speed of a rotorcraft, comparing the vertical speed to a vertical speed safety threshold, and performing vortex ring state (VRS) avoidance in response to the vertical speed exceeding the vertical speed safety threshold. The performing the VRS avoidance includes determining a power margin available from one or more engines of the rotorcraft, limiting the vertical speed of the rotorcraft in response to the power margin exceeding a threshold, and increasing a forward airspeed of the rotorcraft in response to the power margin not exceeding the threshold.

An aircraft uses trajectory-based control algorithms for blade pitch (or twist). This approach greatly enhances the ability of the actuator to accurately achieve the desired blade pitch and to track the commanded pitch position. An actuator includes an electronic rotor blade controller that converts communicated or desired changes in pitch (or similar parameter) to actual physical effects that match the desired changes as closely as possible. The controller preferably includes a motor drive circuit, such as an h-bridge, a communication circuit for connection to external commands, and a processor with associated enabling circuitry (e.g. memory, I/O) to coordinate and implement the control.

An aircraft uses trajectory-based control algorithms for blade pitch (or twist). This approach greatly enhances the ability of the actuator to accurately achieve the desired blade pitch and to track the commanded pitch position. An actuator includes an electronic rotor blade controller that converts communicated or desired changes in pitch (or similar parameter) to actual physical effects that match the desired changes as closely as possible. The controller preferably includes a motor drive circuit, such as an h-bridge, a communication circuit for connection to external commands, and a processor with associated enabling circuitry (e.g. memory, I/O) to coordinate and implement the control.

A method of automating entry of an aircraft into autorotation includes detecting a loss of engine power, analyzing a sensed height and sensed airspeed of the aircraft, determining an adjusted position of one or more control surfaces of the aircraft in response to the sensed height and sensed airspeed, and automatically moving the one or more control surfaces to the adjusted position.

A method of automating entry of an aircraft into autorotation includes detecting a loss of engine power, analyzing a sensed height and sensed airspeed of the aircraft, determining an adjusted position of one or more control surfaces of the aircraft in response to the sensed height and sensed airspeed, and automatically moving the one or more control surfaces to the adjusted position.

A rotorcraft including a pilot control having a sensor that generates pilot control position data, a flight control that controls a flight characteristic of the rotorcraft, a trim system connected to the pilot control and configured to move the pilot control, and a flight control computer (FCC) configured to receive the pilot control position data from the sensor. The FCC executes a first flight control process and generates, according to the first flight control commands, a trim signal indicating a target position for the pilot control and to send the trim signal to the trim system to cause the trim system to attempt to move the pilot control to the target position to reflect a position of the flight control, and to monitor a working state of the trim system and execute a retrim process in response to determining that the trim system has failed.

A rotorcraft including a pilot control having a sensor that generates pilot control position data, a flight control that controls a flight characteristic of the rotorcraft, a trim system connected to the pilot control and configured to move the pilot control, and a flight control computer (FCC) configured to receive the pilot control position data from the sensor. The FCC executes a first flight control process and generates, according to the first flight control commands, a trim signal indicating a target position for the pilot control and to send the trim signal to the trim system to cause the trim system to attempt to move the pilot control to the target position to reflect a position of the flight control, and to monitor a working state of the trim system and execute a retrim process in response to determining that the trim system has failed.