Abstract: Tip surfaces of aerofoils of a bladed disk are repaired by an additive layer manufacturing process in which a laser beam is directed at the tip surface to create an interaction zone while metallic powder is delivered from powder delivery nozzles onto a locus of delivery of larger area than the interaction zone. The bladed disk and the powder delivery nozzles are situated within a controlled environment enclosure, while a laser generating the laser beam is situated outside the enclosure. The laser interaction zone trajectory is controllable independently of the movement of the powder delivery nozzles and so can execute rapid accelerations and decelerations, and changes of direction, enabling complex space filling scanning patterns to be performed on the tip surface.

Abstract: A compressor section for a gas turbine engine, the compressor section including a circumferential row of stator vanes, a circumferential row of rotor blades, and a casing arrangement. A row of bleed ports are provided in the casing arrangement. Each of the bleed ports extends radially and is curved such that an outlet of the port is rearward of and is circumferentially offset in a direction of rotation of the rotor blades from an inlet of the port.

Abstract: The manufacture of a casing which has a boss includes providing two canister portions a first defining an outer wall geometry of a casing including a boss and a second defining an inner wall geometry of the casing. The casing is made using known PHIP methods. The second canister portion includes an array of holes or recesses which, when the canister portions are aligned, face a recess on the first canister portion which defines the boss such that in the nett shape COS an array of pedestals is provided aligned with the boss. The dimension from an exposed end of a pedestal to an exposed surface of the boss is sufficient to receive a bolt thread of the minimum length required to secure a component to the boss.

Abstract: A gas turbine engine includes a circumferential row of vanes directly upstream of an asymmetric gas flow path. At a given spanwise position, a tangential and axial position of the outer guide vanes varies along the circumferential row of vanes. One or more of the vanes are leant such that the tangential and axial position of one or more vanes of the circumferential row of vanes varies in a spanwise direction.

Abstract: A liner element for a gas turbine combustor having a structural wall with fixing apertures provided therethrough. The liner element has a unitary construction defining a cooling side and combustion side, and a plurality of effusion holes extending between a cooling side surface of the element and a combustion side surface of the element. The liner element is configured to be affixed to the structural wall of a combustor with its cooling side surface spaced from the wall to define a chamber between the cooling side surface and the wall, and the liner element further includes integrally formed and non-threaded protuberances on its cooling side, the protuberances being arranged to engage and extend through respective fixing apertures in the combustor wall. Also disclosed is a method of thermally insulating the liner element.

Abstract: Methods of vibration testing a component are provided. In a model of the component, define alignment points corresponding to physical features and define measurement points at positions which vibrate when excited at predefined excitation frequencies (fe), the excitation frequencies (fe) each corresponding to one or more vibrational modes. On the component measure the position of the physical features corresponding to the alignment points in the model and calculate the position of the laser source. Excite the component at an excitation frequency and measure the amplitude of vibration at each measurement point. Extract the mode shape from the measured vibration amplitudes. In the model, rotate a local co-ordinate system (x, y, z) at each measurement point until one axis is directed towards the laser source. Extract the mode shape from the component model. Compare the mode shapes extracted from the model and from measured vibration amplitudes.

Abstract: A lean burn combustor includes a first wall and a second wall spaced from the first annular wall. Angularly spaced axially extending coolant collection manifolds collect coolant from the space between the first and second walls. A plurality of rows of axially spaced apertures extend through the first wall to supply coolant into the space between the first and second walls and one row of aperture is positioned between each pair of adjacent manifolds. The second wall extends the full length of the combustor. The second wall has a circumferentially extending wall extending towards and contacting the first wall and the wall is spaced from the downstream end of the second wall. An annular supply manifold supplies coolant to the space between the first and second walls downstream of the circumferentially extending wall and the manifolds supply coolant to the manifold. A film of coolant is discharged from the space.

Abstract: This disclosure concerns an adaptive repair method, for example for aerofoil blade components. The method generates a digitized model of a physical component and uses data from the digitized model to align a part of the physical component with a nominal CAD model of the component. A combination of the digitized data and data from the nominal CAD model are then used to create an adapted model for repair of the component.

Abstract: A gas turbine engine comprising in flow series: a fan; a series of outlet guide vanes; and a bifurcation. The outlet guide vanes are more densely distributed in a region circumferentially aligned with the bifurcation than in a region circumferentially offset from the bifurcation.

Abstract: An aircraft pneumatic system includes a main gas turbine engine including a main compressor, a recuperated auxiliary gas turbine engine including a core compressor having an inlet in fluid communication with a main compressor bleed of the main gas turbine engine and an environmental control system inlet in fluid communication with the main compressor bleed of the main gas turbine engine. The environmental control system includes a compressor driveable by power provided by the auxiliary gas turbine engine.

Abstract: A system for controlling the geometry of a variable geometry compressor. The system having: a mechanical linkage operable to vary the compressor geometry; a first fluid-powered actuator arranged to operate the linkage and configured to be powered by a pressurized supply of an incompressible fluid; and a second fluid-powered actuator arranged to operate the linkage and configured to be powered by a pressurized supply of a compressible fluid. Wherein the first and second actuators are further arranged to operate in combination on the mechanical linkage such that a first actuator force exerted by the first actuator on the mechanical linkage sums with a second actuator force exerted by the second actuator on the mechanical linkage.

Abstract: A method and apparatus for welding a first component to a second component. A scanning head is positionally calibrated within a localised work envelope including the components, the positional calibration being referenced to at least one datum feature within the work envelope. Profiles of the components are scanned within the localised work envelope using the calibrated scanning head. A cloud point data image of defined coordinate positions of surfaces and edges to be welded within a space envelope is generated from the scanned profiles. A robotic welding torch electrode tip is scanned using the calibrated scanning head to determine a defined coordinate position of the electrode tip within the space envelope. The components are welded using the torch, the torch controlled using the cloud point data image and the defined coordinate position such that the electrode tip is held at pre-determined stand-off positions around the components during the welding.

Abstract: A method of forming a composite article involves the steps of: providing a formed article, the formed article comprising a plurality of non-crimp fibre fabrics with each non-crimp fibre fabric comprising at least two dry-fibre layers; stabilising the plurality of non-crimp fibre fabrics; machining a surface of the formed article having exposed ply terminations to provide a smooth blended surface with chamfered plydrops; positioning the machined formed article in a second mould; infiltrating the second mould with a polymer matrix resin; and curing the machined formed article to form the composite article.

Abstract: There is disclosed a fuel injector arrangement for a gas turbine engine, the fuel injector arrangement comprising: a fuel spray nozzle comprising an engaging feature; and a burner sleeve comprising a swirler; wherein the burner sleeve comprises a connecting feature. The engaging and connecting features are engageable so as to removably couple the fuel spray nozzle to the burner sleeve and inhibit relative movement between the fuel spray nozzle and the swirler. A method of assembly of a fuel injector arrangement is also disclosed. The method comprises providing a fuel spray nozzle comprising an engaging feature; and providing a burner sleeve comprising a swirler; wherein the burner sleeve comprises a connecting feature. The method further comprises bringing the engaging and connecting features into engagement so as to removably couple the fuel spray nozzle to the burner sleeve and inhibit relative movement between the fuel spray nozzle and the swirler.

Abstract: A lubrication system for a gas turbine engine, the system comprising: a gearbox, the gearbox comprising a sump; an oil tank; a primary gearbox lubrication system configured to pump oil from the oil tank to lubricate the gearbox with a gearbox primary feed; a secondary gearbox lubrication system, configured to lubricate the gearbox with oil from the sump when the oil level in the sump reaches a predetermined level; wherein the system is configured to increase the oil level in the sump to at least the predetermined level in response to a failure of the primary gearbox lubrication system.

Abstract: A joint configured to be connected to a pipe for providing a conduit through a wall for the contents of the pipe, the joint comprising an inner joint section defining a bore through the joint; an outer joint section, configured to be connected to the wall; and, an intermediate joint section that connects the inner joint section to the outer joint section and has a lower stiffness than the inner joint section and the outer joint section.

Abstract: A method of manufacture comprising: controlling additive manufacturing using a plurality of parameters to melt a metal to provide an object, at least one parameter of the plurality of parameters having a value selected to cause porosity in at least a first portion of the object; and controlling hot pressing of the object.

Abstract: A gas turbine engine has an engine core, a bypass duct, an engine principal rotational axis and a core annulus surrounding the engine principal rotational axis and radially disposed between the engine core and the bypass duct. The engine radial direction is defined as perpendicular to and intersecting the engine principal rotational axis. An accessory gearbox is located in the core annulus. The accessory gearbox has a sequence of spur gears for driving engine accessories. For each spur gear, the spur gear is mounted for rotation about a respective spur gear rotational axis that is non-parallel with the engine principal rotational axis, the spur gear rotating within a respective spur gear rotational plane perpendicular to the spur gear rotational axis, the spur gear rotational plane intersecting said spur gear, wherein the spur gear rotational plane is offset with respect to the engine radial direction.

Abstract: A component including a first flange located in a first section of the component, the first flange including a contact surface. The component also including a second flange located in a second section of the component. The first flange is configured to attach to the second flange, and the second flange includes a contact surface configured to contact the contact surface of the first flange. The contact surface of the first flange and the contact surface of the second flange each has an undulating surface profile, where each undulating surface profile is defined by at least one peak point and at least one trough point connected by a curved line extending in at least one of a radial or a circumferential direction relative to a central axis of the component.

Abstract: A doctor device configured for use in recoating in an operating additive layer manufacturing apparatus. The doctor device includes at least one blade having a first surface and a second surface. The at least one blade is configured to move in a first direction and a second direction, which is opposite to the first direction. The first surface is configured to bend in the second direction upon the at least one blade moving in the first direction and contacting a surface of an additive layer, and the second surface is configured to be rigid upon the at least one blade moving in the second direction and contacting the surface of an additive layer, such that the at least one blade does not bend.