Abstract: An assembly for mounting a circumferential shroud to a casing, including a plurality of arcuate shroud segments collectively forming the circumferential shroud. Each segment includes a circumferentially extending wall and a channel extending from the wall. The channel is receivable in a hole passing through a circumferential casing and has a first connector. A fastener has a head and a shank, which is receivable in the channel and has a second connector that engages with the first connector. A first spacer receives the channel and a second spacer receives the shank and sit adjacent the head of the fastener on either side of the casing. The spacers can be selected to adjust for optimal radial positioning of the shroud and of probes received within a space defined between the casing and the shroud for monitoring rotor speed and the tip air gap of a turbine rotor contained in the casing.

Abstract: Method and apparatus for classifying defect in component having a monocrystalline structure.

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: An apparatus for supporting a tool in an assembled apparatus. The apparatus includes a support structure, the support structure having a central member and a plurality of support members pivotally mounted on the central member. The support members are movable between a non-deployed position in which the support members extend a minimum distance from the central member and a deployed position in which the support members extend a maximum distance from the central member.

Abstract: An aircraft pneumatic system comprises a main gas turbine engine (10) comprising a main compressor (14, 16), a recuperated auxiliary gas turbine engine (40) comprising a core compressor (42) having an inlet in fluid communication with a main compressor bleed (32) of the main gas turbine engine(10) and an environmental control system inlet in fluid communication with the main compressor bleed (32) of the main gas turbine engine (10). The environmental control system comprises a compressor (68) driveable by power provided by the auxiliary gas turbine engine (40).

Abstract: A pressure vessel having a diameter greater than or equal to 1 m and made by laser cladding an inner surface of the vessel, the laser cladding following a helical path.

Abstract: The invention is a method that combines the following components: 1. a high pass filter designed to have sufficiently small phase delay and roll-off value in transition band as well as sufficiently good attenuation; 2. a distortion detection and reconstruction introduced by the application of the high pass filter by extraction the significant frequency components in relevant frequency band; 3. a signal compensation that reshapes the output of the high pass filter by matching the filter's phase delay and attenuation characteristics so as to approximate low frequency component extraction that would be produced by an ideal filter (very sharp frequency transition and no delay); 4. a time-domain detection and correction method that addresses special circumstances under which the compensation would be inaccurate to achieve real-time estimate in normal circumstances, and 5. a time-domain correction method during and immediately after sudden changes in composite signal (spike) is detected.

Abstract: A turbomachine casing assembly including a casing adapted to encase an aerofoil structure, the aerofoil structure having a tip, a leading edge and a trailing edge, the casing substantially surrounding the tip of the aerofoil structure, wherein the casing has a set-back portion extending from a position in the region of the leading edge or the trailing edge of the aerofoil structure part way towards a position in the region of the respective other edge and set back from the remainder of the casing away from the aerofoil structure, such that the set-back portion permits a flow over a corresponding portion of the tip of the aerofoil structure.

Abstract: A method of reducing dynamic imbalance in a bladed rotor assembly by axially adjusting one or more of the blades so as to redistribute mass along the geometric axis of the assembly. The blades may be axially adjusted to form a counterbalancing couple. Additional correction masses may be added for supplemental correction of couple imbalance or residual static imbalance in the bladed rotor assembly. The invention offers a reduction in the weight penalty associated with conventional balancing corrections carried out on the bladed rotor assembly.

Abstract: A pressure controlled chamber arrangement comprising a chamber, one or more seals arranged in use to limit fluid flow between the inside and outside of the chamber and a vent system arranged in use to remove a vent flow of fluid from the inside of the chamber. The vent system at least contributes to the formation of a pressure drop across the one or more seals from the outside to the inside of the chamber. The vent system comprises a flow controller arranged in use to control the quantity of fluid removal via the vent system in accordance with the sealing performance provided by the one or more seals, the vent system giving increased quantity of fluid removal for decreased sealing performance.

Abstract: An electrical assembly is disclosed in which two flexible printed circuits are electrically joined. This allows greater lengths of flexible printed circuits to be provided, for example for gas turbine engine harnesses. Each flexible printed circuit has a terminating region having electrically conductive through holes that are connected to respective electrical tracks of the flexible printed circuit. The terminating regions are adjacent each other in the electrical assembly, and an electrically conductive pin is passed through the aligned through holes, then permanently bonded in position, for example by welding. This results in a robust, reliable connection of two flexible printed circuits.

Abstract: A heat exchange arrangement for a gas turbine engine. The arrangement includes a first conduit for an engine component cooling fluid and a second conduit for a second fluid. The arrangement further includes a heat exchange portion in which fluids flowing through the first and second conduits are in a heat exchange relationship. A valve is provided, which is configured to moderate the mass flow rate of one of the fluids through the heat exchange portion. The arrangement includes divert valve in the first conduit which diverts flow to the second conduit as the flow in the second conduit is moderated to reduce thermal shock in the heat exchange portion.

Abstract: A method is provided of processing one or more blades of a row of blades which forms part of a rotor for a gas turbine engine. The method includes: providing a rotor disc having a slot for mounting one or more blades; loading the blades in the slot and loading the wax blocks in or adjacent the slot, the wax blocks being configured and positioned such that, on loading, the blades shear material from the wax blocks, the sheared wax blocks reducing a range of tilt angles which can be adopted by the blades; and performing a processing operation on the loaded blades.

Abstract: A variable speed generator for producing AC electrical power includes an alternator powerable by rotational action to generate a first AC current, and a first rectifier which rectifies the first AC current from the alternator. The generator further includes a main exciter having a first field winding which receives the rectified first AC current, and having a first armature which produces in response a second AC current. The generator further includes a second rectifier which rectifies the second AC current from the first armature. The generator further includes a main generator having a second field winding which receives the rectified second AC current, and having a second armature which produces in response an output AC current. The second field winding is configured to provide a plurality of selectively activatable pole configurations which differ in the number of their poles, such that the frequency of the output AC current can be varied by switching between the pole configurations.

Abstract: A method of applying a thermal barrier coating to a metallic article including ball nose milling the surface of the metallic article to produce a pattern in the surface of the metallic article and to produce a compressive residual stress in the subsurface layers of the metallic article. The pattern includes a plurality of pockets and projections on the surface of the metallic article. A thin adherent layer of oxide is created on the metallic article. A ceramic coating is applied to the oxide layer on the surface of the metallic article such that the ceramic coating deposits on the surface of the metallic article in the pockets and on and around the projections. The ceramic coating is applied as a plurality of columnar ceramic grains extending substantially perpendicularly away from the metallic article and the columnar ceramic grains extending from the oxide layer on the metallic article.

Abstract: There is disclosed a gas turbine engine comprising a bypass duct defined between a radially inner wall and a radially outer wall. A support radially extends across the bypass duct. The upstream end of the support acts as a source region. A sink region is provided adjacent to and upstream from the source region to at least partly compensate for aerodynamic effects caused by the source region.

Abstract: A perforated composite panel comprises a substrate and an applied layer, the substrate having a first surface and an opposite second surface. A method of forming the perforated composite panel comprises the steps of: i. cutting a plurality of first holes in the substrate; ii. positioning the applied layer against the substrate such that a surface of the applied layer overlays the first surface of the substrate to thereby form the composite panel; iii. locating the composite panel in a fixture, the fixture having one or more datum features; iv. determining the location and axis direction for each of the first holes in the substrate, relative to the or each datum feature; and v. cutting a plurality of second holes in the applied layer, each of the plurality of second holes being coincident and coaxial with a corresponding one of the plurality of first holes.

Abstract: A seal segment for bounding a hot gas flow path within a gas turbine engine, including: a plate having an inboard side which bounds the hot gas flow path in use, an outboard side and fore and aft cooling circuits, wherein the fore and aft cooling circuits are fluidically separated from one another within the plate and each has at least one tortuous path between an inlet on the outboard side of the plate and an exhaust.

Abstract: A fuel injector includes a central member arranged on axis of fuel injector and a first member arranged around central member. A first swirler is arranged between central member and first member. A pilot fuel injector is arranged to supply fuel onto inner surface of first member. A second member is arranged between downstream end of first member and downstream end of shroud. A second swirler is arranged between upstream end of first member and upstream end of shroud and between downstream end of first member and upstream end of second member. A third swirler is arranged between downstream end of shroud and second member. A main fuel injector is arranged to supply fuel into an annular passage between first member and second member and a fourth swirler extends through first member.

Abstract: A nickel-base superalloy consisting of, by weight: 14.6% to 15.9% cobalt; 11.5% to 13.0% chromium; 0.8% to 1.2% iron; 0.2% to 0.60% manganese; 2.00% to 2.40% molybdenum; 3.30% to 3.70% tungsten; 2.90% to 3.30% aluminium; 2.60% to 3.10% titanium; 3.50% to 5.10% tantalum; 1.20% to 1.80% niobium; 0.10% to 0.60% silicon; 0.02% to 0.06% carbon; 0.010% to 0.030% boron; 0.05% to 0.11% zirconium; up to 0.045% hafnium; and the balance being nickel and impurities.