Abstract: A composite component, such as an aerofoil component for a gas turbine engine, comprises a body and a platform which are formed from respective body and platform preforms. The body preform includes fibres which are directed laterally of the preform, forming a cavity in the end of the preform. The platform preform includes a projection constituting a deltoid filler which is received in the cavity. The projection includes a 3D woven structure of reinforcement fibres so that the cavity is occupied by fibres to give the platform a generally uniform volume fraction. A further platform preform fits over the body preform so that the lateral fibres are sandwiched between the platform preforms.

Abstract: A selective rotation arrangement for a shaft, the arrangement including a housing mountable spaced from the shaft and an engagement member with distal and proximal ends which is selectively movable relative to the housing towards or away from the shaft between an operating position towards the shaft and a rest position clear of the shaft, the engagement member having a gear member at the distal end thereof which is engageable with the shaft in the operating position to permit turning of the shaft by the engagement member, but is disengaged from the shaft in the rest position.

Abstract: An aerofoil has first and second panels spaced apart from each other to provide a cavity, the cavity containing a damping material, the first panel has at least one protrusion extending therefrom within the cavity towards the second panel, the protrusion having a proximal end and a distal end, wherein the proximal end is secured to the first panel and the distal end is slidably mounted to the second panel.

Abstract: A gas turbine engine rotor blade has an airfoil portion containing one or more internal conduits. Each conduit extends to an end of the airfoil portion. The blade has a shroud at the end of the airfoil portion for sealing the blade to a facing stationary engine portion. There is a fillet portion which joins the end to the shroud. The fillet portion eases the transition from the outer surface of the airfoil portion to the outer surface of the shroud and has a cavity which extends from each conduit and expands laterally relative thereto. The area of the cavity on a cross-section through the fillet portion perpendicular to the radial direction of the engine and at an expanding part of the cavity is greater than the area of the conduit, or the combined areas of the conduits, on a parallel cross-section at the end of the airfoil portion.

Abstract: A variable vane assembly, for example of stator vanes in a gas turbine engine, comprises vanes 16 which can be turned together about their longitudinal axes by means of a unison ring 26 which is turned by an actuator 28 about the engine axis. The unison ring 26 is coupled to the vanes 16 by levers 24. The unison ring 26 has varying stiffness along its circumference, increasing in the direction away from the drive point 58 at which the actuator 28 acts. The varying stiffness may be achieved by varying the radial thickness of the unison ring 26. The unison ring is thus able to resist ovalisation so that the vanes 16 move together.

Abstract: A fan assembly 1 for a gas turbine, the assembly 1 comprising: a fan surrounded by a fan casing 2; a resilient, flexible containment material 4 around the outside of the fan casing 2 for containing a detached fan blade which breaches the casing 2 during a fan blade off event, and a retaining cable arrangement for resisting separation of a first and second portion of the casing 10, 12 as a result of said breach, wherein the cable arrangement comprises: a continuous length of retaining cable 14 extending around the fan casing 2 on the outside of the containment material 4, the retaining cable 14 being slidably or rollably secured to each of the first and second portions 10, 12 at a plurality of positions around the fan casing 2 to form respective cable spans 14a, 14b between the casing portions 10, 12, there being sufficient overall slack in the cable 14 for accommodating radial flexing of the underlying containment material 4 upon impact of said detached fan blade.

Abstract: A method of joining plates of material to form a predetermined structure, the method comprising: assembling a first plate (40) of a material comprising at least one recess (100) against a second plate (80) of material such that the at least one recess (100) of the first plate (40) is in an exterior surface of the first plate (40) on a side of the first plate opposite to the side which faces the second plate (80); bonding a portion (120) of the first and second plates (40, 80) to one another; superplastically forming the bonded plates, wherein the superplastic forming causes the material of the second plate (80) which is opposite to the at least one recess (100) of the first plate (40) to be driven towards the recess (100), and wherein the unbonded portion of the second plate (80) is deflected away from the plate to form the predetermined structure.

Abstract: A manufacturing process that comprises placing an article within a particulate medium (4), the article being provided with a molded body (8) of small ceramic particles. On application of heat and pressure the small ceramic particles are pushed between the particulate medium (4) to permit localized deformation of the article (2).

Abstract: A method for providing an indication of thrust available from a gas turbine engine, the method comprises measuring fan aerodynamic speed to produce an actual fan aerodynamic speed measurement, determining a difference between the actual fan aerodynamic speed measurement and an expected fan aerodynamic speed measurement, and if the difference is less than a predetermined threshold value, indicating that sufficient thrust is available.

Abstract: A gas turbine engine is disclosed which comprises a bypass duct, a core engine, and a fluid mixing arrangement. The fluid mixing arrangement is configured to mix a bypass flow of fluid and a secondary flow of fluid, the secondary flow of fluid being drawn from the core engine. The arrangement comprises a flow-duct terminating with an outlet and being arranged to direct said secondary flow through the outlet and into the bypass flow. The arrangement is characterised by the provision of a delta-shaped wing in the region of the outlet, said wing extending at least partially across the duct and being configured to generate lift from said secondary flow effective to produce at least one trailing vortex extending into said bypass flow. The fluid mixing arrangement can be used as a ventilation arrangement or as part of a bleed valve arrangement in the gas turbine engine.

Abstract: A gas turbine engine is proposed which comprises a bypass duct, a core engine, and a fluid mixing arrangement. The fluid mixing arrangement is configured to mix a bypass flow of fluid and a secondary flow of fluid, the secondary flow of fluid being drawn from the core engine. The arrangement comprises a flow duct terminating with an outlet and being arranged to direct said secondary flow through the outlet and into the bypass flow. The arrangement is characterised by the provision of a wing in the region of the outlet, said wing extending at least partially across the duct and being configured to generate lift from said secondary flow effective to produce at least one trailing vortex extending into said bypass flow. The fluid mixing arrangement can be used as a ventilation arrangement or as part of a bleed valve arrangement in the gas turbine engine.

Abstract: Apparatus, for the localised treatment of part of a blade (14), comprises an enclosure (16) that is placed in a spaced relationship around the blade (14). Nozzles (20) extend through the enclosure (16) and direct a flow of gas onto both sides of the blade (14). The gas may be heated or cooled prior to delivery to the nozzles (20). The gas jets impinge upon the blade (14) to treat it.

Abstract: The present invention provides a seal assembly for sealing between two relatively slideable members of non-circular cross-section. A plurality of adjacent seal members may be staggered and grouped within a groove so that all leakage surfaces between the two relatively slideable members are sealed. Multiple seal members or seal member groups may be used to reduce leakage caused by incomplete contact of the seal members with leakage surfaces. An actuator system may comprise various embodiments of the present invention to enable the actuation of one member in relation to another.

Abstract: A method is provided for determining vibration frequencies of rotating blades mounted on a rotor which rotates relative to and is supported by a rotor support structure. The method includes the steps of: (a) determining possible vibration frequencies of the blade from blade displacements corresponding to the times at which a blade passes a stationary timing probe; (b) converting a vibration signal detectable at the support structure into a vibration frequency spectrum; and (c) identifying the blade vibration frequency by matching a peak in the vibration frequency spectrum with one of the possible blade vibration frequencies.

Abstract: An aerofoil 26 for a gas turbine engine (10, FIG. 1) comprises a cavity 38, a cellular material 42 located in the cavity 38 for stiffening the aerofoil 26, and a vibration damping medium 44 located in the cavity 38 for damping the aerofoil. The cellular material 42 is preferably a metal foam bonded to the inner surface 34a, 36a of the hollow aerofoil 26, and the vibration damping medium 44 is preferably a viscoelastic material. Various methods for fabricating the aerofoil 26 are also described.

Abstract: An arrangement for controlling flow of fluid to a component of a gas turbine engine, the arrangement comprising: a conduit, coupled to a supply of fluid, for providing fluid to the component of the gas turbine engine; a magnetic valve for at least partially restricting the conduit and having a valve member with at least a first configuration in which the conduit is at least partially restricted and a second configuration in which the conduit is relatively open, wherein the configuration of the valve member is controlled by magnetic flux in a magnetic circuit which includes at least one member comprising ferromagnetic material, whereby the configuration is responsive to the temperature of the ferromagnetic material.

Abstract: A guide vane arrangement 20 for a gas turbine engine (10, FIG. 1) includes a vane member 21 extending between inner and outer platforms 22, 24 which are respectively mounted on inner and outer mounting members 42, 34. One of the inner and outer platforms 22, 24 includes a resilient that abuts the respective inner or outer platform 22, 24 to permit relative movement between the inner or outer platform 22, 24 and the respective inner or outer mounting member 42, 34.

Abstract: An aerofoil (20) for a gas turbine engine (10) is hollow to define an interior volume (24) through which cooling air flows. Passages (26) interconnect the interior volume (24) with the exterior of the aerofoil (20). Each passage (26) is provided with an inlet (32) within the interior volume (24) which is elongated along an axis (36) parallel with the direction of cooling air flow through the interior volume (24). The arrangement reduces any tendency for the passages (24) to block though the build up of dirt particles.

Abstract: In order to provide noise suppression, bumps or undulations are provided on a nozzle surface in order to vary the convergent-divergent ratio between that surface and an opposed nozzle surface. By such an approach, a circumferential variation in the shock cell pattern is created and the flow is deflected so as to enhance turbulent mixing thereby suppressing noise.

Abstract: A reformer module (10) comprises a hollow support member (12) having at least one passage (14) extending longitudinally therethrough. The hollow support member (14) has an external surface (20), a barrier layer (22) arranged on at least a portion of the external surface (20) of the hollow support member (12), a catalyst layer (24) arranged on the barrier layer (22) and a sealing layer (26) arranged on the catalyst layer (24) and the external surface (20) of the hollow support member (12) other than the at least a portion of the external surface of the hollow support member (12). By providing the barrier layer (22) and the catalyst layer (24) on the exterior surface (20) of the hollow support member (12), the distribution of the barrier layer (22) and/or the catalyst layer (24) may be more precisely controlled and thus a non-uniform distribution of barrier layer (22) and/or catalyst layer (24) may be achieved.