Abstract: An apparatus and method is disclosed for determining a temperature characteristic at a first location on a wheel or a brake assembly of an aircraft landing gear. The temperature characteristic at the first location is determined using relationship information based on a first temperature at a second location of the wheel or the brake assembly of the landing gear, the relationship information representing a relationship between the temperature characteristic at the first location and the first temperature. Also disclosed is a method to determine the relationship information.

Abstract: A method of retrofitting a wing of a fixed wing aircraft is disclosed including the steps of providing an existing aircraft wing with a main fixed wing portion, and the main fixed wing portion having a tip end and an existing movable flight control surface connected adjacent the tip end. The existing movable flight control surface is then removed from the main fixed wing portion, and a wing tip device and movable flight control surface are selected as a pair to replace the existing movable flight control surface, with the selected movable flight control surface having an aerodynamic surface of different shape to the shape of the flight control surface removed from the wing. The selected wing tip device and movable flight control surface are then fitted to the main fixed wing portion.

Abstract: An aircraft landing gear arrangement with an airbag attached inside a landing gear bay is disclosed. The airbag has a deflated configuration and a first inflated configuration, wherein, when the landing gear is in the extended position and when the airbag is in the first inflated configuration, the airbag closes off the landing gear bay. The airbag may substantially close off the landing gear bay. The airbag may comprise an external surface, wherein the external surface of the airbag closes off at least a significant proportion of the landing gear bay and lies substantially flush with an external surface of the aircraft body. An aircraft, methods of operating a landing gear arrangement, and methods of operating an aircraft are disclosed.

Abstract: An aircraft structure, for example a wing, including a skin. The skin has an external surface, on an outer face of the skin. The skin has an internal surface, located opposite the external surface on an inner face of the skin. The aircraft structure includes a laminar flow control system including a compressor. The aircraft structure is so arranged that the exhaust air from the compressor is directed onto the internal surface of the skin of the aircraft structure, for example thus providing hot exhaust air which function as an ice protection system (whether by de-icing or anti-icing). A method of providing ice protection on a surface of an aircraft using exhaust air from a laminar flow control compressor is also described.

Abstract: A joint for connecting a first aircraft structure to a second aircraft structure such that relative rotation and relative translational movement of the first and second aircraft structures along a first axis is permitted, whilst relative translational movement of the first and second aircraft structures along axes orthogonal to the first axis is substantially prevented. The joint includes a bracket having an opening aligned with the first axis; a pin aligned with the first axis and extending through the opening; and a bearing mounted in the opening. The bearing has an inner bearing surface defining a bore through which the pin extends, which is configured for translational sliding contact with the pin, and a part-spherical outer bearing surface configured for rotational sliding contact with the opening.

Abstract: A winglet for attachment to a wing portion of an aircraft is disclosed having a winglet tip and a winglet root opposite from the winglet tip. The winglet has an opening for receiving therethrough a connector for connecting the winglet to a wing portion in use. The winglet has a retainer internal of the winglet for use in retaining the connector relative to the winglet. The retainer has a hole that extends along an axis that passes through the opening for receiving therethrough a portion of the connector when the connector is located through the opening. The retainer includes a body for reacting against a retention component with which the connector engages in use.

Abstract: A winglet for attachment to a wing portion of an aircraft is disclosed having a winglet tip and a winglet root opposite from the winglet tip. The winglet has an opening for receiving therethrough a connector for connecting the winglet to a wing portion in use. The winglet has a retainer internal of the winglet for use in retaining the connector relative to the winglet. The retainer has a hole that extends along an axis that passes through the opening for receiving therethrough a portion of the connector when the connector is located through the opening. The retainer includes a body for reacting against a retention component with which the connector engages in use.

Abstract: A duct stringer is disclosed including a structural member with a hat-shaped cross-section. The structural member has a crown, a pair of webs and a pair of feet. A channel member with a U-shaped cross-section has a base and a pair of flanges. The flanges of the channel member are co-cured to opposed inner faces of the webs of the structural member. The structural member and the channel member together provide a duct with a closed cross-section which is adapted to transport fluid, for instance in an aircraft wing to provide a vent function in an aircraft fuel system.

Abstract: An aircraft (1002) including a wing (1001), having a fixed wing (1005) with a wing tip device (1003) moveably mounted at the outer end thereof. The wing tip device (1003) is moveable between: a flight configuration; and a ground configuration about an axis of rotation. The wing tip device (1003) and the fixed wing (1005) meet along an interfacing cut line (1035). The interfacing cut line (1035) includes a curved section (1039) cent red on the axis of rotation (1011), the radius of the curved section constantly increasing as the cut line passes around the axis (for example a spiral shape).

Abstract: Apparatus for laminar flow control for a skin panel for an aircraft including a body for receipt into a recess of the skin panel. The body defines a chamber. The body includes an outer portion defining one or more micro apertures through the outer portion, each of the one or more micro apertures being in fluid communication with the chamber. The body includes a support portion supporting the outer portion, the support portion defining at least one outlet for allowing air to be drawn from the chamber in use by a suction means in fluid communication with the outlet in use. The apparatus is arranged such that, in use, air is drawn through the one or more micro apertures into the chamber and out of the outlet, thereby to promote laminar airflow over the outer portion in use.

Abstract: A brake cooling period prediction system for predicting a brake cooling period following a braking event, comprising a sensor apparatus in communication with a prediction apparatus. The sensor apparatus includes a torque sensor for measuring the torque reacted by a brake during a braking event; a wear sensor for measuring a wear state of the brake; and an environmental sensor for measuring at least one ambient condition of the environment of the brake. The prediction apparatus includes a memory storing information relating to the thermal behaviour of the brake; and a controller configured to receive a torque measurement, a wear measurement and an ambient condition measurement from the sensor apparatus; and predict a cooling period based on the received torque, wear and ambient condition measurements, and the information relating to the thermal behaviour of the brake.

Abstract: A control system has first and second processing modules for controlling retraction and extension of an aircraft landing gear assembly. The processing modules operate independently providing redundancy. Each processing module is configured to perform a first sequence of steps for retracting the landing gear assembly and a second sequence of steps for extending the landing gear assembly. A step of switching control from one processing module to the other (e.g. an avionics side changeover step) is performed (a) as part of the first sequence of steps, but only after the landing gear assembly has been retracted, or (b) as part of the second sequence of steps. By ensuring that the step of switching control is performed at such times, and not for example between initiation of the first sequence of steps and the retraction of the landing gear assembly, the landing gear assembly may be retracted sooner after such initiation.

Abstract: A wing assembly with at least two ribs is disclosed. Each rib defines a rib plane and has a peripheral edge. A fluid pipe extends through each rib plane and is disposed external to the peripheral edge of each rib. The fluid pipe is coupled to each rib.

Abstract: A cap is disclosed having a collar portion with three or more contact regions arranged to contact the end of a fastener around which the collar portion is provided, the collar portion having a lobed shape in cross-section such that an outwardly projecting lobe extends between each neighbouring pair of contact regions. An advantage of this lobed arrangement is that the cap can tolerate relatively large manufacturing tolerances at the fastener end. The cap may be for fitting over a nut or fastener head, with the contact regions of the cap being arranged to contact corresponding contact regions on a cylindrical collar base portion of the nut or fastener head. The diameter of this cylindrical collar portion may not be well controlled, so that the manufacturing tolerance is high. The lobed shape of the cap base ensures that the contact regions will always provide a good frictional engagement with the nut, whether the cylindrical collar is undersized, oversized, or at its nominal diameter.

Abstract: A panel assembly with a panel and a stringer is disclosed. The stringer has a stringer foot and an upstanding stringer web. The stringer foot has a flange which extends in a widthwise direction between the stringer web and a lateral edge and in a lengthwise direction alongside the stringer web, and a foot run-out which extends between the flange and a tip of the stringer foot. The foot run-out is bonded to the panel at a foot run-out interface. Reinforcement elements, such as tufts, pass through the foot run-out interface into the panel. The reinforcement elements are distributed across the foot run-out interface in a series of rows including an end row nearest to the tip of the stringer foot and further rows spaced progressively further from the tip of the stringer foot. At least the end row has three or more of the reinforcement elements which are distributed along a polygonal curve.

Abstract: A cap for forming a sealed cavity around an end of a fastener is disclosed. The cap has a cap body with an annular base terminating at a base rim which surrounds an opening into a central cavity. The cap also has an annular skirt providing an annular pocket between the skirt and the base. An inlet hole is provided in the skirt which is in fluid communication with the annular pocket. A protuberance protrudes in the annular pocket and faces the inlet hole to promote a flow of sealant injected through the inlet hole to flow annularly around the annular pocket.

Abstract: A cap for forming a sealed cavity around an end of a fastener protruding from a surface of a structure is disclosed. The disclosure relates to a spark prevention cap. The cap has an annular base with an annular base terminating at a base rim. The base rim surrounds an opening into a central cavity for receiving the end of the fastener. The base rim lies in a base rim plane around at least a majority of a circumference of the annular base. An annular skirt provides an annular pocket in which a sealant material is received. A biasing configuration is configured to positively bias the base rim against the surface of the structure.

Abstract: A spring assembly 100 for aircraft landing gear 10 including: an interface 110 via which the spring assembly 100 is attachable to a support 1a; a loading point 120 for receiving a load from one or more wheels 150 or skids in use, wherein the loading point 120 is movable relative to the interface 110; a spring system 130 that is configured to apply a resilient biasing force to the loading point 120 to oppose movement of the loading point 120 relative to the interface 110. The spring system 130 is configured so that, during application of an increasing load to the loading point 120 against the resilient biasing force of the spring system 130, a spring rate of the spring system 130 changes from a first spring rate k1 to a second spring rate k2, the second spring rate k2 being less than the first spring rate k1.

Abstract: A clutch for use in actuating an aircraft wing tip device is disclosed. The clutch includes first and second friction members each having a frusto-conical friction surface, and a third friction member arranged coaxially with, and between, the first and second friction members. The third friction member has first and second frusto-conical friction surfaces. When the clutch is engaged, the first and second friction surfaces of the third friction member are brought into contact with the friction surfaces of the first and second friction members, respectively. The clutch also includes spacer means operable to separate the friction surfaces from one another when the clutch is in a disengaged state.

Abstract: A composite component adapted to be formed into an aerofoil, a method of forming an aerofoil, an aerofoil, an aircraft wing and a forming jig. The method involves forming a flat layup sheet of plies (1) to be folded about a central leading edge region (6) of the layup into an aerofoil shape, applying to the flat layup (1) one or more layups of plies (9, 10) shaped as spars, partially curing the layup (1) with the spars attached, folding the resulting partially cured composite component (30) about the leading edge region (6) in a forming jig (19) so that opposing edges (4, 5) of the sheet meet as a trailing edge (36) of the aerofoil (35), clamping the jig (19) closed, and curing the composite component (30) and adhesive in the forming jig (19) to form the finished aerofoil (35).