An aircraft includes an airfoil and a hinge member to rotatably couple the airfoil to a structure of an aircraft. The hinge member defines at least a portion of a rotational axis. The aircraft also includes an indexing mechanism coupled to the airfoil and configured to, in a first state, inhibit rotation of the airfoil about the rotational axis, and in a second state, to permit rotation of the airfoil about the rotational axis between a first position and a second position that is angularly indexed relative to the first position. The aircraft further includes an actuator to selectively change a state of the indexing mechanism from the first state to the second state, from the second state to the first state, or both.

An aircraft including a battery pack having a plurality of battery cells arranged to vent into a venting region of the battery pack. A path is defined between the venting region and an exterior of the aircraft, whereby thermal products vented by the cells can exit the aircraft via the path. In some embodiments, the venting region is or is in fluid communication with an air channel through which air flows from an aircraft air inlet to an aircraft air outlet. In other embodiments, the path joins the venting region and an opening in an external surface of the aircraft.

An aircraft with rear mounted engines, comprising a vertical tail plane and a horizontal tail plane, in which the engines are mounted on top of the horizontal tail plane, such that the horizontal tail plane comprises an inner fixed part attached to the fuselage of the aircraft, the inner fixed part comprising an elevator, and two outer movable parts, each one of the outer movable parts being located at each side end of the horizontal tail plane which is furthest away from the fuselage of the aircraft, such that both the inner fixed part and the outer movable parts are at least partially subjected to a flow coming from the engines when the engines are in use.

An aircraft with rear mounted engines, comprising a vertical tail plane and a horizontal tail plane, in which the engines are mounted on top of the horizontal tail plane, such that the horizontal tail plane comprises an inner fixed part attached to the fuselage of the aircraft, the inner fixed part comprising an elevator, and two outer movable parts, each one of the outer movable parts being located at each side end of the horizontal tail plane which is furthest away from the fuselage of the aircraft, such that both the inner fixed part and the outer movable parts are at least partially subjected to a flow coming from the engines when the engines are in use.

A pylon assembly for a tiltrotor aircraft includes a fixed pylon having an outboard end. A rotor assembly is rotatably coupled to the fixed pylon and is operable to rotate between a a vertical takeoff and landing orientation and a forward flight orientation. The rotor assembly includes a proprotor operable to produce a slipstream. A wing extension is rotatably coupled to the outboard end of the fixed pylon. The wing extension is operable to rotate generally with the rotor assembly such that a minimal dimension of the wing extension remains in the slipstream of the proprotor.

A test apparatus is provided for testing a sensorless check device of an actuator. The sensorless check device is arranged to be used by mechanically moving a check device pin from a resting position to an actuation position and then releasing the check device pin to allow it to return to a resting position urged by an elastic return mechanism. The test apparatus comprises: a piston for contact with an actuator surface associated with the check device pin; a piston spring for urging the piston toward the actuator surface, wherein the piston spring is softer than the elastic return mechanism of the check device; and an adjustment and testing mechanism.

A lower attachment system for a trimmable horizontal stabiliser actuator comprising: a ballnut for being disposed on a screwshaft of the actuator and forming a part of a primary load path of the lower attachment system; a trunnion connected to the ballnut and forming a part of the primary load path of the lower attachment system; a failsafe plate disposed about the trunnion and forming a part of a secondary load path; a secondary connection connected to the failsafe plate and forming a part of the secondary load path; a sheet plate attached to a first mounting point on the secondary connection and a second mounting point on the ballnut; and an adjustment mechanism provided with the sheet plate for adjusting the size or position of the sheet plate to adapt it to fit a distance between the first and second mounting points.

A lower attachment system for a trimmable horizontal stabiliser actuator comprising: a ballnut for being disposed on a screwshaft of the actuator and forming a part of a primary load path of the lower attachment system; a trunnion connected to the ballnut and forming a part of the primary load path of the lower attachment system; a failsafe plate disposed about the trunnion and forming a part of a secondary load path; a secondary connection connected to the failsafe plate and forming a part of the secondary load path; a sheet plate attached to a first mounting point on the secondary connection and a second mounting point on the ballnut; and an adjustment mechanism provided with the sheet plate for adjusting the size or position of the sheet plate to adapt it to fit a distance between the first and second mounting points.

A pylon assembly for a tiltrotor aircraft includes a fixed pylon having an outboard end. A rotor assembly is rotatably coupled to the fixed pylon and is operable to rotate between a a vertical takeoff and landing orientation and a forward flight orientation. The rotor assembly includes a proprotor operable to produce a slipstream. A wing extension is rotatably coupled to the outboard end of the fixed pylon. The wing extension is operable to rotate generally with the rotor assembly such that a minimal dimension of the wing extension remains in the slipstream of the proprotor.

A pylon assembly for a tiltrotor aircraft includes a fixed pylon having an outboard end. A rotor assembly is rotatably coupled to the fixed pylon and is operable to rotate between a generally vertical orientation in a vertical takeoff and landing mode and a generally horizontal orientation in a forward flight mode. The rotor assembly includes a proprotor operable to produce a generally vertical slipstream in the vertical takeoff and landing mode and a generally horizontal slipstream in the forward flight mode. A wing extension is rotatably coupled to the outboard end of the fixed pylon. The wing extension is operable to rotate generally with the rotor assembly such that a minimal dimension of the wing extension remains in the slipstream of the proprotor.