There is provided an actuator comprising an output shaft and a control system configured to move the output shaft for actuating a component. The control system comprises a first drive system comprising a first movable component, and a second drive system comprising a second movable component. The first component and the second component are connected to the output shaft, and each other, by a connecting member that moves with the first component and the second component to move the output shaft for actuating a component. The control system further comprises one or more bearing arrangements configured to permit movement of the connecting member by the first movable component or the second movable component upon failure, disengagement, shutdown or other stoppage of the second drive system or the first drive system, respectively.

A transmission or gearbox assembly with fail-safe means for providing redundancy where failure can lead to loss of torque transmission between component parts of the assembly, the assembly comprising a plurality of first components in torque transmitting engagement and at least one second component associated with at least one of the first components, the second component being joined to the respective first component by a discontinuous joint. Preferably, each first component of the system has a corresponding second component joined thereto by a discontinuous joint.

An electric actuator to be mounted on an object having a stationary section and a movable section is provided. The electric actuator is configured to actuate the movable section of the object. The electric actuator is provided with a case fixedly attached to the stationary section, and includes a gear mechanism provided in the case. The gear mechanism includes a rotational member rotatable about a common axis and connected with a first motor, an internal gear formed in the rotational member, a sun gear rotatable about the common axis and connected with a second motor, and a planetary gear provided between the internal gear and the sun gear. The planetary gear is connected with an output section for actuating the movable section of the object. The rotational member is rotatably supported a bearing provided between an inner surface of the case and an outer surface of the rotational member.

An electric control device having manipulation means. The electric control device has a first measurement system and a second measurement system respectively taking a first measurement and a second measurement of the current position of the manipulation means. A processor unit compares the first and second measurements in order to generate a control signal as a function of said current position, said processor unit considering that the manipulation means are in a neutral position when the first and second measurements do not correspond to the same position for the manipulation means.

A secondary load path assembly includes: a secondary load path comprising: a plate; a secondary nut; and a transfer plate secured to the plate and configured to connect the plate and the secondary nut in load transfer engagement. The transfer plate has an opening therethrough, an axis defined through the opening, and the secondary nut protruding axially through the opening; wherein, in a state in which load is not transmitted via the secondary load path, a clearance is provided between the secondary nut and the opening. The assembly also includes a locking unit configured to lock the secondary nut to the transfer plate when load is to be transmitted through the secondary path, the locking unit comprising a lock arranged to axially move to a lock position in which it is located in the clearance between the secondary nut and the opening to lock the secondary nut to the transfer plate.

A helicopter autopilot system includes an inner loop for attitude hold for the flight of the helicopter including a given level of redundancy applied to the inner loop. An outer loop is configured for providing a navigation function with respect to the flight of the helicopter including a different level of redundancy than the inner loop. An actuator provides a braking force on a linkage that serves to stabilize the flight of the helicopter during a power failure. The actuator is electromechanical and receives electrical drive signals to provide automatic flight control of the helicopter without requiring a hydraulic assistance system in the helicopter. The autopilot can operate the helicopter in a failed mode of the hydraulic assistance system. A number of flight modes are described with associated sensor inputs including rate based and true attitude modes.

An actuator having an output slidable between extended and retracted positions is provided. The actuator includes a primary module having a power drive, power screw rotatable by the power drive, and a nut operable to translate rotation of the power screw to linear motion of the nut across the power screw. The actuator includes a secondary module having a power drive, a shaft rotatable by the power drive, a power screw, and a nut. The power screw is slidably coupled to and rotatable by the shaft, and coupled to the output. The nut is coupled to the power screw and is operable to slide linearly across the shaft by rotating through the nut. Both the primary nut and secondary power screw are operable to move the output to the extended position or the retracted position depending on the rotational direction of the primary power screw and secondary power screw.

A slat track device (7) for an aircraft wing (1) including a beam-shaped main load bearing track structure (9) connected to a slat (5) and movably connected to a main wing (3), a guidance surface (11) at the track structure (9) and guided along a corresponding guidance device (19) at the main wing, a connection device (13) at the track structure (9) connecting the track structure (9) to the slat (5), and an engagement device (15) at the track structure (9) and configured to engage a drive member (33) of a drive unit (37) provided at a main wing (3). The slat track device has redundant main load paths achieved by the track structure (9) having a first track member (41) and a separate second track member (43) both connected to the connection device (13) and the engagement device (15).

An actuator having an output slidable between extended and retracted positions is provided. The actuator includes a primary module having a power drive, power screw rotatable by the power drive, and a nut operable to translate rotation of the power screw to linear motion of the nut across the power screw. The actuator includes a secondary module having a power drive, a shaft rotatable by the power drive, a power screw, and a nut. The power screw is slidably coupled to and rotatable by the shaft, and coupled to the output. The nut is coupled to the power screw and is operable to slide linearly across the shaft by rotating through the nut. Both the primary nut and secondary power screw are operable to move the output to the extended position or the retracted position depending on the rotational direction of the primary power screw and secondary power screw.

A failsafe bar connection of a screw actuator includes a failsafe bar for transmitting load via a secondary load path, the failsafe bar having a bar-end with a convex thrust surface; and an attachment part for coupling load to an aircraft structure, the attachment part having a socket for retention of the bar-end, the socket providing a concave thrust surface. A contact mechanism is provided to monitor relative displacement of the convex thrust surface within the concave thrust surface in a direction along an axis of the attachment part. In this way, changes in backlash and loading of the secondary load path can be detected. The contact mechanism comprises a protuberance extending from the bar-end along the main rotational axis of the failsafe bar and a displaceable contact surface provided by a displaceable member in the attachment part, the relative position of which is monitored by a displacement sensor.