A trimmable horizontal stabiliser actuator (THSA) control system includes least one main THSA motor for driving the THSA in response to inputs from a flight control computer (FCC), a pilot trim control system for manual control of the THSA by a pilot overriding the FCC. The pilot trim control system comprises a trim control for receiving an input from the pilot, the trim control including a trim control sensor for detecting the input from the pilot and providing a pilot trim control signal; a THSA trim control motor for driving the THSA in response to the pilot trim control signal; and an electronic override system for giving inputs from the pilot priority over inputs from the FCC.

A flight control system includes an active control inceptor, a flight control computer, and a force trim release. The active control inceptor includes a control member movable from a first position to a second position to command a vehicle-body rate and including a detent position that holds an attitude. The flight control computer generates a trim command from the second position, a reference position, and a vehicle-body state. With the force trim release selected when the control member is moved from the first position to the second position, the first position is designated as the reference position and the second position is designated as the detent position. Upon deselection of the force trim release with the control member at the second position, the second position is designated as the reference position and the trim command is designated as the detent position.

Aircraft, fly-by-wire systems, and controllers are provided. An aircraft includes a trim control system and a fly-by-wire system. The trim control system is configured for controlling surfaces of the aircraft. The fly-by-wire system is communicatively coupled with the trim control system and includes an input device and a controller. The input device is configured to receive a re-trim input from a user. The controller is communicatively coupled with the input device and is configured to control the trim control system, to obtain the re-trim input from the user, and to set a pitch trim of the aircraft based on a stable flight condition at a present airspeed of the aircraft in response to the re-trim input from the input device.

A device for releasably mounting an autopilot control circuit to a flight control component of an aircraft, includes a frame that holds a component of an autopilot control circuit; a first coupler releasably fastened to the frame and operable to releasably mount the frame to the airframe of an aircraft; and a second coupler releasably fastened to the frame and operable to releasably mount the frame to a flight control component of the aircraft. When the device is releasably mounted in an aircraft's cabin and the autopilot control circuit is engaged, the autopilot control circuit controls an aspect of the aircraft's flight by moving the second coupler relative to the first coupler. With the device one can releasably mount an autopilot control circuit to an aircraft that does not have one and use the autopilot control circuit and device to control one or more aspects of the aircraft's flight. Then, after the flight is finished, one can remove the device and autopilot control circuit for use in another aircraft.

Provided are airplane trim systems and methods of controlling such systems. These systems utilize smaller portions of the stabilizer total travel range for takeoff trims, in comparison to other trim systems. A trim system described includes stabilizer and elevator, and these components are used together to achieved a takeoff total tail pitching moment. The elevator or, at least a portion of the elevator operating range, is available for flight control. As such, takeoff trim settings include stabilizer and elevator orientation settings. Addition of the elevator to control the takeoff tail pitching moment allows reducing the stabilizer total travel. The elevator orientation can be changed much faster than that of the stabilizer providing pilot more control.

A device for releasably mounting an autopilot control circuit to a flight control component of an aircraft, includes a frame that holds a component of an autopilot control circuit; a first coupler releasably fastened to the frame and operable to releasably mount the frame to the airframe of an aircraft; and a second coupler releasably fastened to the frame and operable to releasably mount the frame to a flight control component of the aircraft. When the device is releasably mounted in an aircraft's cabin and the autopilot control circuit is engaged, the autopilot control circuit controls an aspect of the aircraft's flight by moving the second coupler relative to the first coupler. With the device one can releasably mount an autopilot control circuit to an aircraft that does not have one and use the autopilot control circuit and device to control one or more aspects of the aircraft's flight. Then, after the flight is finished, one can remove the device and autopilot control circuit for use in another aircraft.

A control system (400) for an active inceptor (103) for a fly by wire aircraft permits a zero force null point to settle to a non-zero displacement trim position. An internal position state of a second order mass spring damper model is moved in conjunction with force-displacement characteristic coordinates. This results in no second order dynamics being superimposed on the feel of the inceptor (103) when dynamically adjusting the trim position, thereby eliminating the possibility of any unpleasant buzzing been felt by the operator of the inceptor during a trimming operation.

In an embodiment, a rotorcraft includes a control element; a first detent sensor connected to the control element, the first detent sensor being operable to generate detent slip rate data indicating movement of the control element and detent state data indicating pilot control of the control element; a first trim motor connected to the control element and operable to generate trim rate data; and an FCC in signal communication with the first detent sensor and the first trim motor, the FCC including an error monitor operable to compare the detent slip rate data with the trim rate data and determine whether the first detent sensor is functional or defective, operable to provide a first flight management function when the first detent sensor is determined to be functional, and operable to provide a second flight management function when the first detent sensor is determined to be defective.

A trimmable horizontal stabiliser actuator (THSA) control system includes least one main THSA motor for driving the THSA in response to inputs from a flight control computer (FCC), a pilot trim control system for manual control of the THSA by a pilot overriding the FCC. The pilot trim control system comprises a trim control for receiving an input from the pilot, the trim control including a trim control sensor for detecting the input from the pilot and providing a pilot trim control signal; a THSA trim control motor for driving the THSA in response to the pilot trim control signal; and an electronic override system for giving inputs from the pilot priority over inputs from the FCC.

A fly-by-wire aircraft and method of flying a fly-by-wire aircraft is disclosed. The aircraft includes a control system for flying the aircraft in one of a proportional ground control mode and a model following controls mode. A control device at a control interface of the aircraft selectively activates a trim follow up function in the control system. When flying the aircraft in a proportional ground control mode, trim follow up function can be activated. The control system can then transition into the model following controls mode with the trim follow up function activated to reduce transient behavior.