A nut arrangement for a screw actuator is disclosed for allowing detection of wear in a primary nut of the screw actuator. The nut arrangement comprises a primary nut for providing a primary load path and a secondary nut for providing a secondary load path. An interface ring may link the secondary nut to the primary nut. A sensor is provided to detect relative axial movement between the primary and secondary nuts. During normal operation, the interface ring is seated by a flexible coupling that allows relative axial displacement of the secondary nut to the primary nut to accommodate wear in the primary nut. The sensor can be used to monitor backlash between the primary and secondary nuts to determine wear of the primary nut.

An actuating device to displace a part of an empennage of a helicopter, including a first part including a first casing fixed to a frame of the helicopter, a first element mounted in rotation with respect to the first casing and a first motor the first element. A second part includes a second casing connected to the part of the empennage, a second element mounted in rotation with respect to the second casing and a second motor driving the second element. A connecting element connects the first part with the second part, being mobile in translation with respect to the first element. Rotation of the first element causes a translation of the connecting element, and is mobile in translation with respect to the second element. Rotation of the second element causes a translation of the connecting element with respect to the second element.

An actuator assembly may comprise a screw shaft having a shaft axis; a drive arrangement pivotally supported about the screw shaft axis for driving the screw shaft, e.g., about the shaft axis or along the shaft axis, and a rod mounted to the drive arrangement at a location off the shaft axis for providing a primary function of reacting torque about the shaft axis on the drive arrangement. The rod may comprise a rod axis and provide a load path along the rod axis for reacting torque. The rod may also comprise a device for which provides a secondary function for the actuator assembly based on the load experienced along the load path provided by the rod.

The invention relates to a flap system for an aircraft high lift system or an engine actuation with a rotary shaft system, one or more drive stations as well as elements for transmitting the drive energy from the rotary shaft system to the one or more drive stations, wherein at least one drive station includes at least two independent load paths with at least one rotational transmission each for actuating the flap kinematics, and per load path at least one mechanically coupling-free synchronization unit is provided for compensating regular load fluctuations between the load paths. The invention furthermore relates to a method for monitoring a flap system with at least two redundant load paths which each comprise at least one rotational transmission, wherein it is cyclically checked whether the difference of the output-side torques of the at least two load paths exceeds a defined threshold value and/or lies within a defined limit range.

A method of increasing the control authority of redundant stability and control augmentation system (SCAS) actuators by utilizing feedback between systems such that one system may compensate for the position of a failed actuator of the other system. Each system uses an appropriate combination of reliable and unreliable inputs such that unreliable inputs cannot inappropriately utilize the increased authority. Each system may reconfigure itself when the other system actuator fails at certain positions so that the pilot or other upstream input maintains sufficient control authority of the aircraft.

A rotorcraft autopilot system includes a series actuator connecting a cockpit control component to a swashplate of a rotorcraft, the series actuator to modify a control input from the cockpit control component to the swashplate through a downstream control component. The rotorcraft autopilot system also includes a differential friction system connected to the cockpit control component, the differential friction system to control the series actuator to automatically adjust a position of the cockpit control component during rotorcraft flight based, in part, on a flight mode of the rotorcraft.

A self-locking actuator for moving a flight control surface of an aircraft and for self-locking in response to an external load applied to the actuator. The actuator includes a motor, a screw, and a drive gear that is rotatably driven by the motor to rotationally couple with the screw. A pawl support is coupled to and rotatable with the screw, and a swivel assembly is coupled to the pawl support for rotational movement with the screw and pivoting movement relative to the screw. The swivel assembly engages a cage that is fixed relative to the rotating screw, drive gear, and swivel assembly. Pivoting of the swivel assembly about a pivot axis engages the swivel assembly with the cage to positively lock with the cage and to prevent rotation of the screw in each of first and second opposite rotational directions of the screw about a rotational axis of the screw.

A drive arrangement for manipulating a vehicle control surface, comprises: a first drive; a second drive; an output member for connecting to the vehicle control surface; first engaging means for selectively engaging and disengaging the first drive and the output member, and second engaging means for selectively engaging and disengaging the second drive and the output member.

An aerodynamic system includes a support structure and an aerodynamic component movably coupled to the support structure via first and second coupling units such that the aerodynamic component can be moved relative to the support structure. The first and second coupling units can transfer a load from the aerodynamic component to the support structure. The system further includes an auxiliary coupling unit coupled between the aerodynamic component and the support structure, and configured to switch from a decoupling state to a coupling state, wherein, in the decoupling state, a load transfer via the at least one auxiliary coupling unit is prevented, and wherein, in the coupling state, a load transfer via the at least one auxiliary coupling unit is enabled.

An actuator system for actuating movement of a control surface of an aircraft wing includes a common input rail connectable to a means for providing movement to said input rail. The system also includes: a plurality of rotary geared actuators RGAs; a common output rail connectable to said control surface; wherein each of said plurality of RGAs is connected to said input rail by an individual input clutch and also connected to said output rail by an individual output clutch, and wherein the input clutch functions independently of the output clutch.