Abstract: A tip clearance control device adapted to control the clearance of a rotating aerofoil structure with a surrounding casing portion, and a method of controlling the tip clearance of a rotating aerofoil structure with a surrounding casing portion. The device includes a member operatively connected to the casing portion; the member having at least a first configuration in which the casing portion is at a first radial position and a second configuration in which the casing portion is at a second radial position, wherein the configuration of the member is controlled by magnetic flux in a magnetic circuit which includes at least one ferromagnetic element including ferromagnetic material, where the configuration of the member is responsive to the temperature of the ferromagnetic element.

Abstract: An airblast fuel injector for a gas turbine engine fuel spray nozzle has, in order from radially inner to outer, a coaxial arrangement of an inner air swirler passage, an annular fuel passage, an annular outer air swirler passage, and an annular shroud air swirler passage. The injector further has an annular shroud having an inner surface profile. Relative to the overall axial direction of flow through the injector the shroud inner surface profile has a convergent section followed by a divergent section, the transition of which forming a first inwardly directed annular nose. The injector further has an annular wall having an outer surface profile, and having an inner surface profile. Relative to the overall axial direction of flow through the injector the wall outer surface profile has a convergent section followed by an outwardly turning section which faces across the shroud air passage to the first nose.

Abstract: This invention concerns a fuel delivery system for an engine, in which two or more discrete fuel compositions are made available to the engine. The system has a vapor trail detection sensor configured to generate a detection signal indicative of a characteristic of a vapor trail. A regulator is configured to regulate a percentage of a first and a second fuel composition delivered to the engine as resultant fuel composition. A controller is arranged to undertake a search of trial fuel compositions by controlling the regulator to deliver to the engine a plurality of trial fuel compositions having different ratios of the first and second fuel compositions. The controller controls delivery of a resultant fuel composition to the engine in response to the vapor trail characteristic detection signals for said plurality of trial fuel compositions.

Abstract: A flow directing device for imparting swirl on a fluid includes a flow directing body having a first surface and opposed second surface. A flow channel is defined in the first surface of the flow directing body for conducting fluids flowing through the flow directing body. The flow channel includes a channel surface set in from the first surface. A swirl bore extends though the flow directing body from the channel surface to the second surface of the flow directing body at an oblique angle relative to the channel surface for imparting a tangential swirl component onto fluids flowing through the swirl bore. Having an asymmetrical terminus portion of the channel surface, and positioning of the swirl bore within the terminus portion, allow control of the swirl direction for flow within the terminus portion and swirl bore.

Abstract: A fan track liner assembly for ducted fan engine which provides for reduced strain and deformation of front of fan case in the event of a fan blade off event. Various assemblies are proposed. In one aspect, assembly includes fan track liner panel and plurality of fasteners which are arranged to secure panel to fan case of engine, wherein: a forward portion of panel includes hinged portion which operates as trapdoor to permit blade or blade fragment to pass through, and fasteners are arranged to fail in the event of blade or blade fragment passing through trapdoor causing panel to be displaced rearwards in fan case. Other aspects provide for reduced height of support on fan case for attaching fan track liner and for collapsible comb box.

Abstract: A combustion chamber including a first fuel injector and a second fuel injector, the first and second fuel injectors being arranged to inject fuel into a mainstream flow of air with the second fuel injector arranged downstream of the first fuel injector. A method of mixing fuel and air in a combustion chamber, including injecting fuel into a mainstream flow of air with a first fuel injector; injecting fuel into the mainstream flow of air with a second fuel injector, which is arranged downstream of the first fuel injector; injecting fuel into the mainstream flow with the first fuel injector such that the resulting mixture between the first and second fuel injectors has an equivalence ratio less than the lean flame stability limit; and injecting fuel into the mainstream flow with the second fuel injector such that a combustion zone is provided downstream of the second fuel injector.

Abstract: A bladed rotor comprises a rotor body 2 carrying blades 6, whose pitch can be varied by means of a pitch input shaft 10. The pitch input shaft 10 drives the respective blade 6 about a spanwise axis X of the blade through a harmonic drive reduction gear 14. The harmonic drive reduction gear 14 comprises a wave generator 16 which is fixed for rotation on the pitch input shaft 10 and a flex spline which meshes with a circular spline 20 and is secured to the blade 6.

Abstract: There is provided apparatus for propagation of a wireless signal through a barrier comprising a first antenna for location on a first side of the barrier, a second antenna for location on a second side of the barrier and a waveguide. The waveguide comprises a conducting member passing through the barrier between the first and second sides. The conducting member is held within an insulator sleeve such that it is spaced from a surrounding metal wall of the waveguide. A wireless signal received by the waveguide on the first side of the barrier is transmitted through the barrier by Transverse Electro-Magnetic (TEM) mode propagation along the waveguide is re-radiated on the second side.

Abstract: A cooling system is provided for cooling a turbine of a gas turbine engine. The system has first and second flow paths for guiding cooling air received from the compressor of the engine. The routes of both flow paths bypass the combustor of the engine. The system also has a preswirler for receiving the cooling air at the ends of the two flow paths, swirling the cooling air tangentially to the engine axis, and delivering the swirled cooling air to a rotor of the turbine. The first flow path is routed through a heat exchanger which cools the cooling air guided by the first flow path relative to the cooling air guided by the second flow path.

Abstract: An apparatus for inspecting a turbomachine includes a plurality of horoscopes, a device to rotate the rotor of the turbomachine and a processor having reference measurements of the rotor blades and/or reference measurements between the rotor blades and the horoscopes. A boroscope is inserted in a casing aperture upstream of the blades to view the leading edge and a portion of one of the surfaces of each blade as the rotor is rotated. A boroscope is inserted in a casing aperture downstream of the blades to view the trailing edge and a portion of one of the surfaces of each blade as the rotor is rotated. The boroscopes supply the images of each of the blades to the processor. The processor analyzes the images of the blades and uses the reference measurements to determine the position and size of any defect on any of the rotor blades.

Abstract: A dynamo-electric machine, for example a marine propulsion unit, includes a stator and a rotor in the form of an impeller. The impeller is rim-driven and includes an annular core of ferromagnetic material, on which are provided layers in the form of an environmental enclosure and electrically conductive sleeves. Appropriate selection of the materials and thicknesses of the layers enables the starting and normal running performance of the machine to be optimized.

Abstract: An aircraft (40). The aircraft comprises a plurality of propellers (46) mounted to wings (44). Each propeller comprises at least one blade (72, 74) coupled to a respective propeller cyclic actuator (78) configured to cyclically alter the pitch of the respective blade (72, 74) as the propeller rotates. The aircraft (40) is configured such that provision of cyclic pitch to the propeller (46) twists at least a portion of the wing (44) about a span of the wing (46) relative to the fuselage (42), to thereby adjust the local angle of incidence of the wing (46).

Abstract: A mandrel includes a support structure; main sectors carried by the support structure and each having a main forming surface; and intermediate sectors carried by the support structure and each having an intermediate forming surface. The main sectors and intermediate sectors are alternately arranged around the axis. The main sectors are moveable relative to the support structure between a radially inner main retracted position, and a radially outer main forming position. The intermediate sectors are moveable relative to the support structure between a radially inner intermediate retracted position, and a radially outer intermediate forming position. The mandrel further includes drive means for moving the main sectors and intermediate sectors from their respective retracted positions to their respective forming positions. The drive means is configured such that each main sector reaches its main forming position before the adjacent intermediate sectors reach their respective intermediate forming positions.

Abstract: An intershaft seal is provided for inner and outer coaxial shafts which rotate relative to each other. The seal is located in an annular space between the shafts and maintains an axial pressure differential between a fluid pressure on the first side of the seal and a different fluid pressure on the other, second side of the seal. The seal includes a first runner which extends circumferentially around a first one of the shafts and projects therefrom into the annular space. The seal further includes a sealing ring which is coaxial with the shafts.

Abstract: An apparatus for pre-stressing a component, the apparatus includes means to direct a beam of radiation in a path through a medium adjacent to the component between a pair of electrodes to produce ionisation in the path through the medium and means to produce an electrical discharge between the pair of electrodes in the path through the medium to produce a pressure pulse in the medium adjacent to the component without the electrical discharge directly contacting the component, the pressure pulse impacting a surface of the component to produce a region of compressive residual stress within the component.

Abstract: This invention relates to a mould assembly for a hot isostatic pressing, HIP, process for fabricating a component, comprising: a first part which includes a shaped surface for forming a first surface of the component, the shaped surface having at least one recess; a second part arranged to move relative to the first part during the HIP process so as to compress a powder in-fill held therebetween, wherein the second part includes a formation configured to focus pressure toward the recess so as to aid consolidation of the powder in-fill at a distal end thereof.

Abstract: A combustion chamber including a first fuel injector and a second fuel injector, the first and second fuel injectors being arranged to inject fuel into a mainstream flow of air with the second fuel injector arranged downstream of the first fuel injector. A method of mixing fuel and air in a combustion chamber, including injecting fuel into a mainstream flow of air with a first fuel injector; injecting fuel into the mainstream flow of air with a second fuel injector, which is arranged downstream of the first fuel injector; injecting fuel into the mainstream flow with the first fuel injector such that the resulting mixture between the first and second fuel injectors has an equivalence ratio less than the lean flame stability limit; and injecting fuel into the mainstream flow with the second fuel injector such that a combustion zone is provided downstream of the second fuel injector.

Abstract: A method of determining a tool path to machine a component, the method comprising the steps of: securing the component to a fixture having a zero point alignment datum, the component and the fixture having respective mobile reference points; aligning the fixture mobile reference points to target reference points on the machine tool; aligning a digitized model of the component to the component mobile reference points; determining the position of the component on the fixture from the component mobile reference points and the fixture mobile reference points; and adjusting a nominal tool path for the machine tool dependent on the position of the component.

Abstract: A fuel injector comprising: a prefilmer; a plurality of discrete fuel sources each arranged to supply fuel to a surface of the prefilmer; wherein the prefilmer comprises circumferential dispersion structure which, in use, spreads the fuel in a circumferential direction as it passes from an impingement point on the surface of the prefilmer to a downstream edge of the prefilmer.

Abstract: A gas turbine engine installation is provided that has a flexible printed circuit board (FPCB) harness to transfer electrical signals, including electrical power, around a gas turbine engine. The FPCB harness is held to the gas turbine engine installation using clips. The clips have a jaw that has two sets of opposing teeth extending from a base, and a mouth through which the FPCB harness is inserted. The teeth point in a direction that has a component from the mouth to the teeth. This means that the force required to insert the FPCB harness into the clip is lower than the force required to pull the FPCB harness out of the clip in the opposite direction. This means that the FPCB harness can be secured in place while aiding ease of assembly.