Abstract: An upper attachment system for a trimmable horizontal stabiliser actuator (THSA) comprises: a housing, holding a yoke and a ballscrew; a nut coupled to the housing and cooperating with the ballscrew such that rotation of the ballscrew relative to the nut results in linear motion of the ballscrew; a recess formed between the yoke and the ballscrew and arranged to receive, in use, an upper part of a tie bar of the secondary load path of the actuator; and a biasing mechanism arranged such that, in use, when no axial load is applied to the tie bar, the yoke and the ballscrew are held by balanced forces from the biasing mechanism in a position within the recess.

Abstract: A device (13) for detecting the breakage of a primary path in a flight control actuator, said actuator having a primary path (1) comprising a rotary hollow screw (2), a secondary path (10) comprising a safety rod (3) that reacts the load passing through the screw (2), said device (13) being characterized in that it comprises a position sensor (15), connected to the screw (2), to measure information representative of the angular position thereof, and a disconnection system (17) able to disconnect the screw (2) position sensor (15) in the event of relative movement of the rod (3) with respect to the screw (2) if there is a break in the primary path (1).

Abstract: The invention relates to a flight-control actuator comprising a control screw (1) that engages with a primary nut (2), the actuator also comprising a secondary nut (5) that engages with the control screw in the event the primary nut fails. The primary nut and the secondary nut are remote from one another, the secondary nut moving substantially along a portion of the screw that is usually not fitted with the primary nut.

Abstract: A device (13) for detecting the breakage of a primary path in a flight control actuator, said actuator having a primary path (1) comprising a rotary hollow screw (2), a secondary path (10) comprising a safety rod (3) that reacts the load passing through the screw (2), said device (13) being characterized in that it comprises a position sensor (15), connected to the screw (2), to measure information representative of the angular position thereof, and a disconnection system (17) able to disconnect the screw (2) position sensor (15) in the event of relative movement of the rod (3) with respect to the screw (2) if there is a break in the primary path (1).

Abstract: The invention relates to a no-back device for a mobile element actuating device including a screw shaft having first and second braking means each comprising a ratchet wheel. These ratchet wheels are mounted opposite one another so that the first braking means are adapted to resist an unwanted movement of the screw shaft in a first direction, and the second braking means are adapted to resist an unwanted movement of the screw shaft in an opposite direction. The no-back device also includes means for detecting the state of the rotation of the ratchet wheels and indicating means for furnishing, according to the state of the rotation of the wheels, an indication concerning the operating state of the no-back device.

Abstract: The assembly comprises a first and a second nut intended to cooperate with a screw in particular provided in an adjustable tailplane actuator for an aircraft, and a mechanical connection between the first and the second nut comprising means for fusible driving of the second nut by the first nut, in which the mechanical connection also comprises adjustable spacing means forming a wedge between the first and second nuts.

Abstract: The assembly comprises a first and a second nut intended to cooperate with a screw in particular provided in an adjustable tailplane actuator for an aircraft, and a mechanical connection between the first and the second nut comprising means for fusible driving of the second nut by the first nut, in which the mechanical connection also comprises adjustable spacing means forming a wedge between the first and second nuts.

Abstract: The invention relates to a no-back device for a mobile element actuating device including a screw shaft having first and second braking means each comprising a ratchet wheel. These ratchet wheels are mounted opposite one another so that the first braking means are adapted to resist an unwanted movement of the screw shaft in a first direction, and the second braking means are adapted to resist an unwanted movement of the screw shaft in an opposite direction. The no-back device also includes means for detecting the state of the rotation of the ratchet wheels and indicating means for furnishing, according to the state of the rotation of the wheels, an indication concerning the operating state of the no-back device.

Abstract: A pneumatic booster operated by a plunger (8) located in a piston (5) with a rear section (82) which operates a valve (91,92,93) to develop a force on the piston (5) to apply a boost force to force-transmission members (12,14). The plunger (8) has a first section (81) connected to the rear section (82) by a spring (15). The front section (81) and the force-transmission members (12,14) defining a retention assembly (16,17) for securing the front section (81) to the piston (5) when a boost force exceeds a predetermined threshold while the plunger (8) is in a maximum actuating position to allow for extended actuation of the booster following a sharp braking action.