Abstract: A rotorcraft includes airspeed sensors, inertial sensors, and a flight control computer (FCC) operable to provide a longitudinal control for the rotorcraft. The FCC receives a first indication of longitudinal airspeed from the airspeed sensors and receives a first indication of longitudinal acceleration from the inertial sensors. The FCC generates a filtered indication of longitudinal airspeed from the first indication of longitudinal airspeed and generates a scaled and filtered indication of longitudinal acceleration from the first indication of longitudinal acceleration. The FCC combines the filtered indication of longitudinal airspeed with the scaled and filtered indication of longitudinal acceleration to generate a determined longitudinal airspeed. The FCC generates a flight control signal to control operation of the rotorcraft, the flight control signal based on the determined longitudinal airspeed.

Abstract: In accordance with an embodiment of the present invention, a method of operating a rotorcraft includes operating the rotorcraft in a heading control mode that includes activating a yaw channel path of a heading controller and deactivating a roll channel path of the heading controller when a speed of the rotorcraft is less than a first speed threshold or a heading error is less than a heading error threshold, and activating the roll channel path of the heading controller and deactivating the yaw channel path of the heading controller when the speed of the rotorcraft is greater than a second speed threshold and the heading error is not less than the heading error threshold.

Abstract: A flight control computer (FCC) for a rotorcraft includes a processor and a non-transitory computer-readable storage medium storing a program to be executed by the processor, with the program including instructions for providing main rotor overspeed protection. The instructions for providing the main rotor overspeed protection include instructions for monitoring sensor signals indicating a main rotor RPM, determining a target operating parameter, determining one or more flight parameters in response to a relationship between the main rotor RPM and the target operating parameter indicating a main rotor overspeed condition. Determining the one or more flight parameters includes determining a setting for a flight control device of the rotorcraft that changes the main rotor RPM, controlling positioning of a pilot control according to the flight parameters, and controlling the flight control device of the rotorcraft according to positioning of the pilot control.

Abstract: A fly-by-wire system for a rotorcraft includes a computing device having control laws. The control laws are operable to engage a roll command or a yaw command in response to deflection of a beep switch of a pilot control assembly, wherein a roll angle for the roll command or a yaw rate for the yaw command is determined based on forward airspeed of the rotorcraft. The beep switch may be disposed on a collective control of the pilot control assembly. The control laws are further operable to disengage the roll command or the yaw command in response to the beep switch being returned from a deflected position to a neutral position. In representative aspects, the roll angle or the yaw rate may correspond to a standard rate turn (e.g., 3° per second).

Abstract: A fly-by-wire system for a rotorcraft includes a computing device having control laws. The control laws are operable to engage a level-and-climb command in response to a switch of a pilot control assembly being selected. The level-and-climb command establishes a roll-neutral (“wings level”) attitude with the rotorcraft increasing altitude. The switch may be disposed on a collective control of the pilot control assembly (e.g., a button on a grip of the collective control). Selection of the switch may correspond to a button depress. The level-and-climb command may include a roll command and a collective pitch command. One or more control laws may be further operable to increase or decrease forward airspeed in response to pilot engagement of the level-and-climb command. The level-and-climb command may correspond to a go-around maneuver, an abort maneuver, or an extreme-attitude-recovery maneuver to be performed by the rotorcraft.