A method includes receiving pump cycle location data associated with a fluid power system. The fluid power system includes a plurality of pumps (including at least a first pump, a second pump, and a third pump). Based on the pump cycle location data having a first value, the method includes activating the first pump as a primary pump. Based on the pump cycle having a second value, the method includes activating the second pump as the primary pump. The method also includes activating the third pump as a secondary pump when the fluid power system is in a multiple-pump operating mode.

A method includes receiving pump cycle location data associated with a fluid power system. The fluid power system includes a plurality of pumps (including at least a first pump, a second pump, and a third pump). Based on the pump cycle location data having a first value, the method includes activating the first pump as a primary pump. Based on the pump cycle having a second value, the method includes activating the second pump as the primary pump. The method also includes activating the third pump as a secondary pump when the fluid power system is in a multiple-pump operating mode.

The invention relates to an actuator (4) for controlling a horizontal stabilizer (3) of an aircraft, including: a primary channel including a screw (6) and a primary nut (7), the primary nut (7) being suitable for engaging with the screw (6), such that a rotation of the screw (6) relative to the primary nut (7) about a rotation axis (X) causes the primary nut (7) to translate relative to the screw (6) along the axis (X), such as to move the horizontal stabilizer (3); a secondary channel including a secondary part (25, 28), and a housing (23, 26), the secondary part (25, 28) being mounted in the housing (23, 26) with play between the secondary part and the housing, in which the secondary channel also includes a play take-up device (27), configured to, in the event of a breakdown of the primary channel causing the secondary part (25, 28) to move relative to the housing, eliminate the play between the secondary part (25, 28) and the housing (23, 26) such as to keep the secondary part (25, 28) in contact with the housing (23, 26).

A Stability and Command Augmentation System (SCAS) for an aircraft, the SCAS including, a first input shaft providing a first rotational input; a second input shaft providing a second rotational input; and a device for summing the first and second rotational inputs to give a rotational output for controlling an actuator. A method of operating a SCAS on an aircraft, the method including providing a pilot input order in the form of a rotating first shaft, providing an augmentation input order in the form of a rotating second shaft, summing the rotation of the pilot input order and the augmentation input order to give an output order; and using the output order to control an actuator.

A system for detecting mechanical failure of a connection between a variable differential transformer and a controlled element. The sensor system includes a variable differential transformer with a housing encapsulating a first coil, a bore in the housing, wherein the bore is adjacent to the first coil, a core disposed in the bore, a shaft connectible between the core, at a first end, and the controlled element, at a second end, and a biasing element connected to the shaft. Responsive to a break in the shaft, the biasing element moves the core to an out-of-range position detectable by at least the first coil.

A system for detecting mechanical failure of a connection between a variable differential transformer and a controlled element. The sensor system includes a variable differential transformer with a housing encapsulating a first coil, a bore in the housing, wherein the bore is adjacent to the first coil, a core disposed in the bore, a shaft connectible between the core, at a first end, and the controlled element, at a second end, and a biasing element connected to the shaft. Responsive to a break in the shaft, the biasing element moves the core to an out-of-range position detectable by at least the first coil.

An aircraft comprises an aircraft structure, a flight control surface attached to the aircraft structure, and a local hydraulic power pack disposed proximal to the flight control surface. The local hydraulic power pack is configured to provide pressurized hydraulic fluid for actuating the flight control surface. The local hydraulic power pack comprises a reservoir for the hydraulic fluid and two hydraulic pumps for pressurizing the hydraulic fluid.

An aircraft comprises an aircraft structure, a flight control surface attached to the aircraft structure, and a local hydraulic power pack disposed proximal to the flight control surface. The local hydraulic power pack is configured to provide pressurized hydraulic fluid for actuating the flight control surface. The local hydraulic power pack comprises a reservoir for the hydraulic fluid and two hydraulic pumps for pressurizing the hydraulic fluid.

A SCAS module includes one or more SCAS actuators wherein each SCAS actuator comprises a piston arranged for linear motion within a hydraulic chamber in response to a flow of hydraulic fluid metered by a valve. The piston comprises a flexible rod or quill for providing a linear output along the first axis, the flexible rod or quill being mounted internally within an annular portion of the piston so that a space is defined around the flexible rod or quill. The flexible rod or quill is capable of deforming into the surrounding space in order to accommodate movement of the flexible rod or quill.

A SCAS module includes one or more SCAS actuators wherein each SCAS actuator comprises a piston arranged for linear motion within a hydraulic chamber in response to a flow of hydraulic fluid metered by a valve. The piston comprises a flexible rod or quill for providing a linear output along the first axis, the flexible rod or quill being mounted internally within an annular portion of the piston so that a space is defined around the flexible rod or quill. The flexible rod or quill is capable of deforming into the surrounding space in order to accommodate movement of the flexible rod or quill.