Abstract: There is disclosed a flow control nozzle for controlling the flow of an incompressible fluid, the flow control nozzle having a flow area and comprising a deformable element comprising a shaped memory alloy (SMA) material wherein within a range of operating temperatures the SMA material is configured to reduce the flow area of the flow control nozzle as the operating temperature increases. The flow control nozzle is thus able to dynamically compensate for changes in operating temperature in order to maintain a constant flow.

Abstract: An actuator rod assembly for a blade pitch control system is provided herein. The actuator rod assembly includes a tubular outer rod and an inner rod. The outer rod has a first end and a second end. The inner rod has a first end and a second end and extends through the tubular outer rod. The inner rod is tensioned against the tubular outer rod so as to place the outer rod in compression.

Abstract: A spool valve arrangement comprising a spool arranged for linear movement within a bore to regulate flow of fluid through the bore according to the linear position of the spool relative to the bore, the spool having an end arranged to be engaged, in use, by a drive member to cause the linear movement, the spool valve arrangement further comprising a sliding block component moveably attached to the spool end and arranged to engage with the drive member, in use, such that the drive member engages with the spool end via the sliding block component and the sliding block component moves relative to the spool to compensate for non-linear movement of the drive member.

Abstract: A gurney flap arrangement includes: an airfoil 2 with a trailing edge 6 and an opening 14 in a surface 8 of the airfoil 2; a gurney flap 1 having a first position in which at least a portion of the gurney flap 1 extends through the opening 14 and projects outwardly from the airfoil surface 8, and a second position in which the gurney flap 1 does not project from the airfoil surface 8 or projects outwardly from the airfoil surface 8 to a lesser extent; and a gurney flap actuator 3 for moving the gurney flap 1 between at least the first position and the second position.

Abstract: A hydraulic damper comprises an outer cylinder, and an inner cylinder slidably mounted within the outer cylinder for movement relative to the outer cylinder along a longitudinal axis. The inner cylinder has a circumferential wall circumscribing a bellows assembly. The bellows assembly comprises a first bellows section, a second bellows section, a damping plate attached to and separating the first and second bellows sections, a first closure element closing an end of the first bellows section opposite the damping plate to define a first chamber, and a second closure element closing an end of the second bellows section opposite the damping plate to define a second chamber. The first closure element is attached to the inner cylinder for movement therewith relative to the outer cylinder. The second closure element is also attached to the inner cylinder for movement therewith relative to the outer cylinder.

Abstract: A linear electromechanical actuator comprises an electric motor, a ball screw shaft driven by the electric motor and a tubular output shaft receiving the ball screw shaft and rotationally coupled thereto. The ball screw shaft has at least one helical groove formed on a radially outer surface thereof and the output shaft has at least one helical groove formed in a radially inner surface thereof. A plurality of ball elements is received within the grooves for rotationally coupling the ball screw shaft to the output shaft. The ball screw shaft further comprises a ball recirculation element mounted in the radially outer surface of the ball screw shaft. The ball recirculation element interrupts the helical groove in the ball screw shaft and has one or more ball recirculating passages. Each ball recirculating passage comprises an inlet portion a recirculation portion and an outlet portion.

Abstract: A gurney flap arrangement comprises: an airfoil with an opening in a surface of the airfoil; a gurney flap having a first position in which at least a portion of the gurney flap extends through the opening and projects outwardly from the airfoil surface, and a second position in which the gurney flap does not project from the airfoil surface or projects outwardly from the airfoil surface to a lesser extent; and a seal disposed about the opening to seal a gap in the opening between the gurney flap and the airfoil.

Abstract: A rotary damper comprising a fixed structure, a rotor configured to rotate about an axis (R-R), and two opposing bellows. The bellows each extend between the rotor and the fixed structure and are attached thereto. The bellows each define a chamber for holding hydraulic fluid and are configured to expand and contract as the rotor rotates. The damper further comprises a damping orifice extending through the rotor or the fixed structure. The bellows are sealingly engaged around the damping orifice and the damping orifice permits fluid communication between the chambers defined by the bellows.

Abstract: A drive lever comprising a first end for insertion into a slot of the hydraulic spool valve. The first end comprises at least two resilient members which resist radial compression (R1, R2) such that they exert a radially outward force (F1, F2) on one or more inner surfaces of the slot when inserted therein. This radially outward force (F1, F2) can account for any backlash that would otherwise be present between the drive lever and the slot due to manufacturing tolerances or wear.

Abstract: A gurney flap arrangement comprises: an airfoil with an opening in a surface of the airfoil; a gurney flap having a first position in which at least a portion of the gurney flap extends through the opening and projects outwardly from the airfoil surface, and a second position in which the gurney flap does not project from the airfoil surface or projects outwardly from the airfoil surface to a lesser extent; and a seal disposed about the opening to seal a gap in the opening between the gurney flap and the airfoil.

Abstract: There is disclosed a flow control nozzle for controlling the flow of an incompressible fluid, the flow control nozzle having a flow area and comprising a deformable element comprising a shaped memory alloy (SMA) material wherein within a range of operating temperatures the SMA material is configured to reduce the flow area of the flow control nozzle as the operating temperature increases. The flow control nozzle is thus able to dynamically compensate for changes in operating temperature in order to maintain a constant flow.

Abstract: An actuator rod assembly for a blade pitch control system is provided herein. The actuator rod assembly includes a tubular outer rod and an inner rod. The outer rod has a first end and a second end. The inner rod has a first end and a second end and extends through the tubular outer rod. The inner rod is tensioned against the tubular outer rod so as to place the outer rod in compression.

Abstract: A load bearing assembly comprises: a lug body; an outer race disposed within and supported by the lug body; an inner race disposed within and supported by the outer race; and a relief slot defined between the adjacent surfaces of the outer race and the lug body, wherein the relief slot is formed in the surface of the outer race.

Abstract: A gurney flap arrangement comprises: an airfoil with an opening in a surface of the airfoil; a gurney flap having a first position in which at least a portion of the gurney flap extends through the opening and projects outwardly from the airfoil surface, and a second position in which the gurney flap does not project from the airfoil surface or projects outwardly from the airfoil surface to a lesser extent; and a seal disposed about the opening to seal a gap in the opening between the gurney flap and the airfoil.

Abstract: A hydraulic damper comprises an outer cylinder, and an inner cylinder slidably mounted within the outer cylinder for movement relative to the outer cylinder along a longitudinal axis. The inner cylinder has a circumferential wall circumscribing a bellows assembly. The bellows assembly comprises a first bellows section, a second bellows section, a damping plate attached to and separating the first and second bellows sections, a first closure element closing an end of the first bellows section opposite the damping plate to define a first chamber, and a second closure element closing an end of the second bellows section opposite the damping plate to define a second chamber. The first closure element is attached to the inner cylinder for movement therewith relative to the outer cylinder.

Abstract: A roller bearing comprises inner and outer rings defining a toroidal inner raceway rotatable about a bearing axis (A). A plurality of concave rolling elements is arranged in a single row between the outer and inner rings. Each of the plurality of concave rolling elements is a symmetrical cylindrical roller having circular ends, a roller axis passing through the center of the circular ends, and a concave side profile that extends continuously between the circular ends. The toroidal inner and outer raceways each have a convex race surface that continuously engages the concave side profile between the circular ends of each concave rolling element with a first radius and extends axially beyond the circular ends of each concave rolling element with a second radius that is less than the first radius.

Abstract: An airfoil structure comprising a main body and at least one control surface attached to the main body by a flexible attachment, the flexible attachment comprising a flexible first surface and a flexible second surface opposed to the flexible first surface, each of the flexible first surface and the flexible second surface having a waveform structure.

Abstract: A roller bearing comprises inner and outer rings defining a toroidal inner raceway rotatable about a bearing axis (A). A plurality of concave rolling elements is arranged in a single row between the outer and inner rings. Each of the plurality of concave rolling elements is a symmetrical cylindrical roller having circular ends, a roller axis passing through the centre of the circular ends, and a concave side profile that extends continuously between the circular ends. The toroidal inner and outer raceways each have a convex race surface that continuously engages the concave side profile between the circular ends of each concave rolling element with a first radius and extends axially beyond the circular ends of each concave rolling element with a second radius that is less than the first radius.

Abstract: A drive lever comprising a first end for insertion into a slot of the hydraulic spool valve. The first end comprises at least two resilient members which resist radial compression (R1, R2) such that they exert a radially outward force (F1, F2) on one or more inner surfaces of the slot when inserted therein. This radially outward force (F1, F2) can account for any backlash that would otherwise be present between the drive lever and the slot due to manufacturing tolerances or wear.

Abstract: A spool valve arrangement comprising a spool arranged for linear movement within a bore to regulate flow of fluid through the bore according to the linear position of the spool relative to the bore, the spool having an end arranged to be engaged, in use, by a drive member to cause the linear movement, the spool valve arrangement further comprising a sliding block component moveably attached to the spool end and arranged to engage with the drive member, in use, such that the drive member engages with the spool end via the sliding block component and the sliding block component moves relative to the spool to compensate for non-linear movement of the drive member.