Abstract: A fan is mounted on a fan shaft which constitutes part of a mainline shaft assembly centered for rotation on an engine axis X-X of a gas turbine engine. When in operation, the fan rotates about the engine axis X-X. A stub-shaft is arranged radially outwardly and concentrically with the fan shaft and adjoins an upstream facing face of a bearing sleeve. A fan catcher arm extends from the stub-shaft through the bearing sleeve and joins a fan catcher ring arranged downstream of the bearing sleeve and having an upstream facing face arranged to abut against a downstream facing face of the bearing sleeve in the event of a fan blade-off. Immediately downstream of the fan catcher ring is formed a shaft end which is configured to couple with an axially adjacent end of a low pressure compressor shaft. Immediately downstream of the bearing sleeve is a shaft end configured to connect with a turbine shaft.

Abstract: A method of manufacturing a vane arrangement for a gas turbine engine comprises providing an aerofoil having a hollow cavity with an open end and providing a support member having a stub with a through hole extending therethrough. The method comprises welding the aerofoil to the stub such that the open end of the hollow cavity of the aerofoil is aligned with the through hole of the stub so as to define a hollow region extending through the support member and stub to the cavity of the aerofoil. During welding a tool is positioned within the through hole and cavity and is aligned with an interface between the stub and aerofoil, the tool being configured to prevent weld splatter onto a surface of the cavity or through hole.

Abstract: A permanent magnet electrical machine has a rotor supporting a circumferential row of permanent magnets. The electrical machine further has a stator coaxial with the rotor and having a circumferential row of stator teeth carrying respective coils. The teeth provide paths for magnetic flux produced by the magnets, thereby electromagnetically linking the magnets and the coils when the rotor rotates relative to the stator. The teeth have respective core portions on which the coils are mounted, and respective tip portions located between the core portions and the rotor, neighbouring tip portions being circumferentially spaced from each other by respective gaps. Each pair of neighbouring tip portions has a bridge member and a thermal switching mechanism carried by a first tip portion of the pair.

Abstract: A transfer coupling includes a static component and a rotatable component arranged concentrically, the static component including a first number of radially extending ports and the rotatable component having a second number of radially extending ports the radially extending ports arranged in a common circumferential plane wherein the ports are configured and arranged, in use, to homogenise a flow area for a fluid being transferred through the ports and thereby create a homogenous volume flow.

Abstract: An electrical machine including a rotor and a stator, at least one of the rotor and stator being provided with superconducting first electrical windings; and a set of one or more screen electrical windings, provided in the form of one or more further superconducting electrical windings, arranged around and radially outward of the first electrical windings; wherein the set of screen electrical windings is arranged to be supplied with an electrical current for generating a magnetic field of suitable magnitude and phase to reduce the magnitude of the magnetic field, generated at least by the first electrical windings during operation of the electrical machine, radially outwards of the screen electrical windings.

Abstract: The present disclosure relates to a geared turbofan engine.

Abstract: There is disclosed an axial flow machine (10) comprising an annular flow path (23); a stator ring (38) comprising a plurality of stators mounted at their radially outer ends and extending into the annular flow path (23); a non-rotating body (24) axially adjacent the stator ring (38); and an annular shroud (42) disposed between the radially inner end of the stator ring (38) and the body (24). The shroud (42) is supported on the stator ring (38) and moveable relative the body (24); and the shroud (42) cooperates with the body (24) to inhibit a flow through a clearance pathway (78) therebetween.

Abstract: An axial piston pump has a fluid inlet, a fluid outlet, and a rotatable, one-piece piston housing carrying one or more pistons movable within one or more respective sleeves formed by the housing. A circumferential row of fixed field members is mounted to the housing at a mounting location formed by the housing, the mounting location being radially outward of the sleeve(s). The pump further has a stator surrounding the piston housing and including a circumferential row of armature windings such that the piston housing and the stator form an electro-magnetic motor operable to rotate the piston housing, and a swashplate engaged with the piston(s) such that rotation of the piston housing relative to the swashplate around an axis of rotation produces reciprocating movement of the piston(s) for the pressurisation of fluid received into the sleeve(s) from the fluid inlet and then discharged from the sleeve(s) to the fluid outlet.

Abstract: An annular air swirler configured to receive a fuel injector in a central bore. The swirler has one or more annular channels, defined by radially facing channel walls and having an inlet for receiving compressed air and an axially distal outlet. The channel walls converge inwardly towards the outlet and swirl vanes extend between opposing faces of the walls. The swirler turns incoming air to create a vortex at the channel outlet. An annular cooling apparatus associated with the air swirler is arranged axially adjacently downstream of the channel outlet(s), and includes a skirt portion radially spaced from a converging portion of the outermost channel wall defining a converging portion of a bowed coolant channel. A radially outwardly extending wall connects with the outermost channel wall and, with a face of the skirt portion, defines a radially outwardly extending portion of the bowed coolant channel adapted for increased heat exchange.

Abstract: A geared turbofan engine include a gas turbine engine for an aircraft, including: an engine core including a turbine, a compressor, and a core shaft connecting the turbine to the compressor; a fan assembly located upstream of the engine core; and a gearbox that receives an input from the core shaft and outputs drive to the fan assembly to drive the fan assembly at a lower rotational speed than the core shaft, the hub including a plurality of slots located around a rim of the hub, each slot receiving a root of a corresponding fan blade, the rim having a minimum radial thickness between a base of each slot and an internal cavity within the hub, wherein the minimum radial thickness is within a range of around 0.5% to around 1.1% of the outer fan diameter.

Abstract: A gas turbine engine for an aircraft, includes: an engine core having a turbine, a compressor, and a core shaft connecting the turbine to the compressor; a fan assembly located upstream of the engine core; and a gearbox receiving an input from the core shaft and outputs drive to the fan assembly so as to drive the fan assembly at a lower rotational speed than the core shaft, wherein the fan assembly has fan blades mounted around a hub, the fan blades having blade tips defining an outer diameter of the fan assembly of from around 220 cm to around 400 cm, the hub having slots located around a rim of the hub, each slot receiving a root of a corresponding fan blade, wherein a ratio of a mass of the hub to a total mass of the fan blades is within the range of around 0.45 to around 0.7.

Abstract: The present disclosure concerns apparatus and methods for reinforcing composite materials by insertion of reinforcement pins. Example embodiments include an apparatus for reinforcing a composite preform, comprising: a carriage for introducing reinforcement pins into the composite preform, the carriage comprising a drill module, a pin feeder module and a tamper module, the assembly being translatable relative to the composite preform, wherein the drill module and pin feeder module are exchangeable between a common actuation position on the carriage.

Abstract: A method of controlling at least part of a start-up or re-light process of a gas turbine engine, the method comprising: increasing an angular velocity of a low pressure compressor; determining if an exit pressure of the low pressure compressor is equal to or greater than a first threshold pressure; in response to determining that the exit pressure of the low pressure compressor is equal to or greater than the first threshold pressure, controlling rotation of the low pressure compressor using a first electrical machine and controlling rotation of a high pressure compressor using a second electrical machine, to increase angular velocity of the high pressure compressor; determining if an exit pressure of the high pressure compressor is equal to or greater than a second threshold pressure.

Abstract: A method of controlling at least part of a start-up or re-light process of a gas turbine engine, the method comprising: controlling ignition within a combustion chamber of the gas turbine engine; controlling rotation of a low pressure compressor using a first electrical machine, and controlling rotation of a high pressure compressor using a second electrical machine, the combustion chamber downstream of the low pressure compressor and high pressure compressor; determining if an exit pressure of the high pressure compressor is equal to or greater than a self-sustaining threshold pressure; and in response to determining that the exit pressure of the high pressure compressor is equal to or greater than the self-sustaining threshold pressure, ceasing controlling rotation of the low pressure compressor using the first electrical machine, and/or the high pressure compressor using a second electrical machine.

Abstract: A method of controlling at least part of a start-up or re-light process of a gas turbine engine, the method comprising: determining when a flame in a combustion chamber of a gas turbine engine is extinguished, during a start-up process or re-light process or during operation; purging the combustion chamber by controlling rotation of a low pressure compressor using a first electrical machine, and controlling rotation of a high pressure compressor using a second electrical machine, the combustion chamber downstream of the low pressure compressor and high pressure compressor; and controlling rotation of the low pressure compressor using the first electrical machine, and controlling rotation of the high pressure compressor using the second electrical machine to restart the start-up process or perform the re-light process.

Abstract: An aerofoil structure (26) for a gas turbine engine (10), the aerofoil structure comprising a carbon composite aerofoil portion (38) and a tip portion (48), wherein the tip portion comprises a tip surface (60) configured to face a corresponding casing structure (30), the tip portion further comprising a ridge line (62) extending along at least a portion of the tip surface, wherein the tip surface comprises a first surface (64) and a second surface (66) provided either side of the ridge line, the ridge line being defined by the intersection of the first and second surfaces, wherein the ridge line is configured to cut into the casing structure during an interaction between the aerofoil structure and casing structure.

Abstract: A nose cone assembly is provided comprising a nose cone, a support ring on which the nose cone is mounted, and an insulating layer disposed between the nose cone and the support ring, the insulating layer at least partially comprising glass fibres. A composite nose cone is also provided comprising an attachment region A, in which composite fibres are oriented substantially perpendicular to an axis of rotation of the nose cone, and an impact region I, in which composite fibres are oriented substantially parallel to the axis of rotation of the nose cone. Also provided is a support ring for a nose cone assembly, the support ring comprising an annular main body and an annular projecting attachment flange, the attachment flange terminating in a plurality of circumferentially spaced attachment tabs, wherein the attachment flange forms with the main body a cross section having at least two C curves.

Abstract: A turbine case cooling system comprises a manifold (21) radially adjacent a portion of a radially outer surface of the turbine case (26) and in fluid communication with one or more of radially inwardly directed outlets (25). The manifold (21) has a first inlet (22) and a second inlet (23). The first inlet (22) is obstructed by a first flow restrictor (22a) and the second inlet (23) is obstructed by a second flow restrictor (23a). The first inlet (22) includes a valve (24) upstream of the first flow restrictor (22a) and the valve is adjustable to control flow of fluid supply entering the first inlet (22).

Abstract: An aircraft fuel pumping arrangement comprises a first fuel pump, an electrically powered motor operable to drive the first fuel pump to deliver fuel to an outlet, a second fuel pump, a gas driven turbine operable to drive the second fuel pump to deliver fuel to the outlet, and a controller operable to control the operation of the gas driven turbine to determine the rate at which the second fuel pump is driven.

Abstract: An aerofoil and an aerofoil assembly, in particular an aerofoil with improved stagnation zone cooling and an aerofoil assembly comprising such an aerofoil. The aerofoil is an aerofoil for a gas turbine engine comprising a pressure surface, a suction surface, a leading edge, a trailing edge, a stagnation zone located in the region of the leading edge, and an elongate channel running along the leading edge at the stagnation zone.