Abstract: A Stability and Control Augmentation System (“SCAS”) module includes a SCAS actuator. The SCAS actuator has a substantially cylindrical hydraulic chamber having a first and second regions. A piston is arranged for linear motion in first and second directions along an axis of the hydraulic chamber. The SCAS module also includes a valve system for controlling a flow of a hydraulic fluid into the hydraulic chamber. The valve system has: at least one supply line arranged to provide a first fluid flow path to the first region of the hydraulic chamber and/or a second fluid flow path to the second region of the hydraulic chamber, and a moveable valve member arranged to have a position between a first and second positions.

Abstract: A seal assembly for a shaft is arranged to extend around an outer circumferential surface of the shaft and includes: a first seal ring having a first ring angled surface; a second seal ring having a second ring angled surface; and an elastic ring disposed between the first seal ring and the second seal ring and in contact with the angled surfaces. The elastic ring is arranged to act on the angled surfaces to bias the first seal ring and second seal ring radially inwardly and apart from one another. The seal assembly can be part of a rotary valve.

Abstract: A bearing assembly includes a housing, an annular outer race located at least partially within the housing, a bearing located at least partially within the outer race, and a nut configured to be secured to a second axial end of the outer race. The outer race has a central axis and comprises a flange at a first axial end, wherein the flange is configured to prevent movement of the outer race relative to the housing in a first axial direction. The nut is configured to prevent movement of the outer race relative to the housing in a second axial direction, the second axial direction being opposite to the first axial direction.

Abstract: A stability control augmentation system and method for a flight control surface of an aircraft. The system includes s an actuator operable for actuating the flight control surface, and a control valve comprising a spool and an integrated augmentation mechanism. The spool and the actuation mechanism are both moveable to open and close a fluid flow path through the control valve to control the actuator.

Abstract: A valve for controlling the flow of hydraulic fluid to a hydraulic motor. The valve includes a sleeve and a spool. The sleeve includes a first fluid flow port for receiving hydraulic fluid from the supply line; a second fluid flow port for supplying hydraulic fluid to a second valve; a third fluid flow port for receiving hydraulic fluid from a first control line; a fourth fluid flow port for receiving hydraulic fluid from a second control line; and a fifth fluid flow port in fluid communication with the return line. The valve is arranged to be actuated to move the spool between a first position and a second position. When the spool is in the second position, the fifth fluid flow port is in fluid communication with the second, third and fourth fluid flow ports and the first fluid flow port is closed by the spool.

Abstract: A pressure regulating shut-off valve has a valve member regulating flow of fluid between an inlet and an outlet. The valve includes a pneumatic actuator having a piston having first and second faces that define first and second volumes within a cylinder. The second face has a greater surface area than the first face. The first and second volumes are fluidly connected to the inlet, and an electrically actuated valve controls the flow of fluid along a fluid path to the second volume. The electrically actuated valve closes the fluid path, when power is supplied to the electrically actuated valve, and opens the fluid path, when power is removed from the electrically actuated valve, which causes the pneumatic actuator to act on the valve member to hold the valve member in a fixed position.

Abstract: A bearing assembly includes a housing, a spherical bearing located within the housing, and two outer races positioned between the spherical bearing and the housing. The outer races are configured in sliding engagement with the spherical bearing to allow the spherical bearing to rotate relative to the housing. The assembly also includes a tightening element configured to engage a first of the two outer races and tighten the outer races against the spherical bearing. The assembly is configured to provide a primary load path from the tightening element to the housing, wherein the primary load path leads from the tightening element to the housing via the outer races whilst bypassing the spherical bearing.

Abstract: A butterfly valve assembly includes: a butterfly element configured to control fluid flow through a main conduit; and a butterfly controller configured to control the butterfly element. The controller includes a first chamber for receiving fluid at a first pressure, a second chamber for receiving fluid at a second pressure, and an actuator responsive to the first pressure and the second pressure. The assembly also includes a relief valve arranged to regulate the first pressure in the first chamber within a predetermined pressure range, wherein the relief valve comprises an adjustment mechanism for adjusting the predetermined pressure range. The butterfly valve assembly may comprise a manual override operable to lock the butterfly element in a fully open position or a fully closed position.

Abstract: There is provided a control module for a hydraulic system. The module comprises a tank and a plurality of valves. The tank is configured to store hydraulic fluid and is substantially cylindrical. The plurality of valves fluidly connect with the tank and are configured to control distribution of hydraulic fluid from the tank to one or more components of the system. The plurality of valves are spaced around a circumference of the tank. One or more passages fluidly connect the tank with at least one of the plurality of valves and/or a first of the plurality of valves with a second of the plurality of valves.

Abstract: A valve assembly for an anti-ice system of an aircraft. The valve assembly comprises: a valve body; a first piston; and a regulating piston. The valve body defines a valve inlet, a valve outlet, a fluid passage between the valve inlet and the valve outlet, and a core portion defining a first chamber by cooperation with the first piston and a regulating chamber by cooperation with the regulating piston. The first piston is moveable between a first position and a second position, and the regulating piston is movable between a first position and a second position. The first piston overlaps the regulating piston when the first piston is its first position and the regulating piston is in its second position.

Abstract: A joint for an actuator of a rotorcraft includes a housing configured to be coupled to an input lever of the actuator; and a rotary bearing coupled to the housing, the rotary bearing comprising an inner race and an outer race and configured to be coupled to a control rod, wherein the inner race and outer race are rotationally fixed relative to each other until a torque applied to the joint exceeds a threshold torque value, upon which there is a relative rotatability between the inner race and the outer race.

Abstract: An apparatus for use in a gas turbine engine is disclosed comprising a bleed valve and an intermediate valve. In use the bleed valve is exposed to a source of pressurised air, and the bleed valve is movable between an open position, in which the bleed valve permits a flow of the pressurised air through the bleed valve and a closed position, in which the bleed valve does not permit a flow of the pressurised air through the bleed valve. The intermediate valve is operatively connected to the bleed valve and configured to selectively open and close the bleed valve, wherein the intermediate valve is configured in a mode of operation to close the bleed valve based on the pressurised air within the bleed valve exceeding a predetermined threshold.

Abstract: A Stability and Control Augmentation System (“SCAS”) module comprising one or more SCAS actuators, the or each SCAS actuator comprising a mechanical component that translates rotational motion to linear motion along a first axis of said SCAS; one or more electric motors for driving linear movement of the mechanical component in response to a command signal; and one or more angular transducers to detect the position of the SCAS actuator along the first axis.

Abstract: A hydraulic actuator is disclosed that comprises a first, fixed portion and a second portion movable relative to the first portion. The second portion comprises a hydraulic actuating device for actuating a component, and the actuator further comprises an intermediate member configured to interconnect the first portion with the second portion and permit movement of the second portion relative to the first portion. The intermediate member is configured to convey hydraulic fluid to the hydraulic actuating device of the second portion through a body of the intermediate member.

Abstract: A valve has a fluid inlet, a housing comprising a first chamber and a fluid passage extending from the fluid inlet to the first chamber, one or more exhaust channels in fluid communication with the first chamber such that, in use, a pressurised fluid entering the first chamber is exhausted through the one or more exhaust channels, a device movable between a closed position and an open position, and a resilient member configured to bias the device towards its closed position. The valve further comprises one or more additional fluid channels having an outlet within each of the one or more exhaust channels that create a Venturi effect in use with the pressurised air exhausted through the one or more exhaust channels.

Abstract: An electromechanical actuator assembly comprises a first actuator and a second actuator. The first actuator and the second actuator are coupled together end-to-end and are independently operable. A method of actuating a moveable element using an actuator assembly, comprises: coupling a first actuator between a fixed structure and a second actuator so that the first actuator is operable to move the second actuator relative to the fixed structure; coupling the second actuator to the moveable element; and moving the moveable element by moving the second actuator using the first actuator.

Abstract: There is provided a control module for a hydraulic system. The module comprises a tank and a plurality of valves. The tank is configured to store hydraulic fluid and is substantially cylindrical. The plurality of valves fluidly connect with the tank and are configured to control distribution of hydraulic fluid from the tank to one or more components of the system. The plurality of valves are spaced around a circumference of the tank. One or more passages fluidly connect the tank with at least one of the plurality of valves and/or a first of the plurality of valves with a second of the plurality of valves.

Abstract: A hydraulic stage includes a hydraulic element located between and sealing a first and second chamber, wherein the first chamber comprises at least one aperture through which fluid is arranged to flow into or out of the first chamber; and at least one piezoelectric element which is positioned adjacent to the at least one aperture and is arranged to deform in response to an applied potential difference such that it blocks or obstructs the at least one aperture to a varying degree according to the level of deformation, so as to control fluid flow into or out of the first chamber. The level of deformation of the piezoelectric element thus reduces or increases an effective size of the inlet or outlet aperture to which it is adjacent, restricting or permitting an increase in fluid flow accordingly.

Abstract: A pressure relief valve includes a first port that receives a first gas at an input pressure, a second port that receive a second gas at a regulating pressure, a third port in communication with the first port via an orifice and that outputs the first gas at an output pressure and a piston movable along an axis and configured to control the passage of gas through the orifice between the first port and the second port, such that the output pressure of the gas is dependent on the axial position of the piston. The valve also in include a resilient member configured to bias the piston and the valve comprises a chamber at least partly defined by the piston and in fluid communication with the second port, such that the force exerted by the gas within the chamber on the piston acts against the action of the resilient member.

Abstract: A regulating piston for a pressure regulating shut-off valve comprises: a tubular sleeve; a first closed end; a second open end; a port defined in the tubular sleeve between the first and second ends, arranged to permit fluid flow between the exterior and interior of the regulating piston; and a support structure disposed within the piston arranged to direct fluid flow between the port and the second open end. The piston can be included in a pressure regulating shut-off valve, and methods for manufacturing the piston and valve.