Abstract: A bypass turbofan gas turbine engine is started by an electric starter motor that is mounted directly about a downstream end or upstream of the low pressure spool of the engine. This causes air to be driven by a fan through a bypass duct around the engine casing. Closures close to substantially seal an outlet of the bypass duct, and the air is directed into a combustion chamber of the engine and through the turbines causing the high pressure spool to pick up speed for starting.

Abstract: A lubricant arrangement is provided for multiple feed pipes to bearings lubrication system. In order to ensure a feed pipe remains substantially full of lubricant fluid, a drainage restrictor configuration is provided. This configuration typically comprises an anti siphon tube, accumulator, a fluid head between a supply pipe and the feed pipe as well as a final loop in the feed pipe formed by limbs. In such circumstances, drainage of lubricant fluid from other feed pipes for other bearings does not siphon lubricant fluid from the feed pipe which may be subject to potential coking as a result of high temperatures and air.

Abstract: A cooling arrangement for a surface of a wall in a gas turbine engine, the wall having a plurality of effusion holes each with an outlet onto the surface for supplying an effusion flow to the surface and an inlet, the inlets of the effusion holes being arranged at the peripheries of groups tessellated on an opposing surface of the wall, each inlet being located on the peripheries of three groups. The arrangement comprises a second wall spaced apart from the opposing surface having impingement orifices each for directing a flow of air in use to a respective impingement location on the opposing surface, each group having a centrally positioned impingement location.

Abstract: The fan duct of a ducted fan gas turbine engine has a fan case lined with a honeycomb structure that acts to absorb the energy of a separated part of a blade. A layer of composite material lining honeycomb structure delaminates/breaks when a separated blade part passes through a further, inner honeycomb liner and hits it. The resulting free end of composite liner wraps round the striking end of the blade part, thus blunting the cutting action of the blade part and spreading the generated forces to the extent that the blade part is de-energised sufficiently to prevent it penetrating the fan case.

Abstract: Control of blade clearance gaps between rotating turbine blades and an associated casing in a gas turbine engine is important in order to maintain operational efficiency. It is desirable to achieve accurate gap control but previous passive and scheduled thermal gap adjustment systems have been relatively course. By provision of a winding through which a specific electrical current is passed in order to create electro-magnetic force for displacement of an armature associated with a seal forming part of the casing it is possible to adjust the gap between that seal and a tip part of a rotating blade assembly. Normally a blade gap monitoring technique is used in association with specific operational requirements with respect to the gap by the control in order to determine the electrical current presented to the winding.

Abstract: With variable airgap reluctance actuators problems arise due to the relationship between actuator mass and displacement range. By providing opposed surfaces in the actuator stator core and armature which have undulations typically in the form of grooves, slots and projections, a greater displacement range can be achieved whilst maintaining performance above a rated displacement force characteristic. In such circumstances by establishing a necessary rated displacement force characteristic, an actuator can be tailored and designed to meet that characteristic over a desired displacement range which has significantly less mass in comparison with a prior actuator arrangement having flat surfaces.

Abstract: A gas turbine engine comprising a bypass duct defined radially outwardly by a nacelle and radially inwardly by a core engine casing. The nacelle comprises a thrust reverser unit having at least one blocker door rotatably attached to a static part and slidably connected to a translating part. The translating part is arranged to move between a stowed position and a deployed position and in the deployed position the blocker door spans the bypass duct. In the stowed position the blocker door is stowed inside the translating part and does not form part of an airwash surface of the bypass duct.

Abstract: It is known with regard to particularly cavities below high pressure turbine discs that mixing of hot gas leakage flows through an inner seal with cooling flows can diminish the effectiveness of that cooling flow when presented to other parts for cooling. By providing a path within a wall which is particularly shaped in portions it is possible to provide entrainment of a hot leakage gas flow away from entry into the cavity. Thus, the cooling flow retains a higher cooling effect and maintains its swirling nature in comparison with prior arrangements where mixing with the hot leakage flow occurred.

Abstract: A turbomachine rotor includes a plurality of turbomachine rotor blades. The turbomachine rotor has a plurality of firtree shaped slots in its radially outer periphery to form a plurality of rotor posts. The turbomachine rotor blades have correspondingly shaped firtree roots to fit in the firtree shaped slots in the turbomachine rotor. The firtree roots of the turbomachine rotor blades comprise a plurality of radially spaced lobes on each of it flanks. The rotor posts of the turbomachine rotor comprise a plurality of radially spaced lobes on each of its flanks. A radially inner lobe of at least one of the turbomachine rotor blades has reduced stiffness such that the load on the radially inner lobe of the at least one turbomachine rotor blade is shared with the other lobes of the at least one turbomachine rotor blade.

Abstract: A method of forming a component (30) by isostatic pressing, the method comprising: providing a canister (4) suitable for isostatic pressing, the canister comprising first and second membranes (14, 16) which, in use, are disposed within the canister (4); the first and second membranes (14, 16) defining a component cavity (24) disposed between the first and second membranes (14, 16), a first tool cavity (26) disposed between the first membrane (14) and an adjacent wall (10) of the canister (4), and a second tool cavity (28) disposed between the second membrane (16) and another adjacent wall (12) of the canister (4); filling the component cavity (24) with the component powder for forming the component (30); filling the first and second tool cavities (26, 28) with a second tool powder; and isostatically pressing the canister (4) to form the component (30).

Abstract: Apparatus for adaptive cooling comprising a first component having at least one aperture extending therethrough with a sacrificial component positioned within the at least one aperture. The first component is operable at a maximum duty temperature and the sacrificial component has a melting or sublimation point below the maximum duty temperature of the first component. The sacrificial component defines an effective aperture the size of which may be increased if, in use, the sacrificial component is subjected to a temperature between the melting or sublimation point of the sacrificial component and the maximum duty temperature of the first component.

Abstract: A rotary coupling having a first element and a coaxial second element, the first and second elements being rotatable relative to each other and defining an annular passage between radially facing walls thereof. The coupling has a sealing ring at an end of the annular passage, the sealing ring being mounted to the wall of the first element and rotating relative to the second element, and having an active configuration in which the sealing ring is urged against the wall of the second element to seal the end of the annular passage, and a return configuration in which the sealing ring does not seal the end of the annular passage. A control system is used to apply a variable load to the sealing ring, wherein the sealing ring moves between the active and return configurations in response to variation in the applied load.

Abstract: A system for cooling cooling-air in a gas turbine engine, the system having an electricity generating fuel-cell, and an arrangement for receiving water produced by the fuel cell, delivering the water to the engine, and cooling cooling-air inside the engine using the water.

Abstract: A flow discharge device, such as a bleed assembly in a gas turbine engine, comprises a discharge outlet member 38 having a skirt 44 which is accommodated telescopically in a housing 36 so as to be displaceable with respect to a wall 27 of a duct 22 from a retracted position (FIG. 2) in which slots 48 in the skirt 44 lie outside the duct 22, and an extended position (FIG. 3) in which the slots 48 open into the duct 22 for the discharge of a secondary fluid into the flow in the duct 22. The discharge outlet member 38 is moved to the extended position by the pressure of the secondary fluid acting on a silencer element 46. A spring 52 returns the discharge outlet member to the retracted position when the flow of the secondary fluid is terminated.

Abstract: The present invention is a collector for collecting washing fluid issuing from a gas turbine engine during and/or after a washing operation. The collector comprises a collection tray and an inlet collector attached at a first end to the collection tray. The second end of the inlet collector is connected to an inlet of the engine, thereby collecting washing fluid issuing from any one or both the inlet and below the engine.

Abstract: This invention relates to heat transfer passage (102) within a component (100) and a component having such a heat transfer passage. The passage (102) comprises opposing side walls (112), a base (110) extending between said side walls and one or more upstanding formations (122) depending from said base between said side walls. The passage is arranged to receive a heat transfer fluid flow during use and the upstanding formation (122) is arranged to induce separation of a boundary layer portion of said heat transfer fluid flow from the base in use. The upstanding formation (122) comprises a projection portion (126) which is spaced from said opposing side walls (112). Such upstanding formations are typically referred to as turbulators.

Abstract: A pre-reformer comprises a non-electrically conducting gas tight duct and an electrically conducting wire arranged in the duct. The electrically conducting wire is electrically isolated from the duct. The duct has an inlet for receiving a hydrocarbon fuel at a first end and an outlet for supplying a pre-reformed hydrocarbon fuel at a second end. At least the inner surface of the duct is chemically inert with respect to the hydrocarbon fuel. An electrical power supply is electrically connected to the electrically conducting wire and a control means controls the supply of electrical current through the electrically conducting wire to provide thermal decomposition of higher hydrocarbons in the hydrocarbon fuel. The performer reduces coking in associated fuel cells and other parts of a fuel cell system.

Abstract: The present invention provided a method of manufacturing a duct for a gas turbine engine or the like from sheet metal material; the method comprising the steps of: fabricating a duct from sheet material (10,12,14) including rolling or folding metal sheet along ruled lines to form a ruled surface geometry approximately corresponding to at least part of a desired irregular final duct geometry; welding corresponding rolled or folded parts of the duct skin together and positioning the duct on a heat treatment fixture (30) having a shape corresponding to the said desired irregular duct geometry; the material of the heat treatment fixture having a greater thermal expansion coefficient than the duct material; heating the duct and fixture substantially to a stress relieving temperature of the duct material such that differential thermal expansion of the duct and fixture at the said stress relieving temperature causes the duct to distort and adopt the shape of the exterior surface of the fixture on which the duct is l

Abstract: A gas turbine engine comprising a core engine a fan and a fan casing surrounding the fan and extending rearwardly to attach to an array of outlet guide vanes characterised in that a cascade is rigidly attached to the fan casing and is connected to the core engine via a second support.

Abstract: Powder metallurgy techniques are utilised to form components and in particular titanium components in moulds. By the nature of the powder forming process, closed surfaces are created in the powder formed component, particularly when hot iso-static pressing techniques are utilised. In order to create surface texturing, and in particular entrant features, a mould lining is associated such that it reciprocates the shape of an underlying mould. The mould lining incorporates surface discontinuities such as holes, slots, spots or folds which result, once the moulded material is formed, in entrant features which can be utilised to enhance bonding through adhesives or other surface features beneficial to a component.