Abstract: A joint between a first component (30) and a second component (32) and the second component (32) comprises a shape memory material component. The first component (30) has a half dovetail shaped slot (34) and the shape memory material second component (32) has a half dovetail shaped attachment feature (36) and the half dovetail shaped attachment feature (36) of the shape memory material second component (32) locates in the half dovetail shaped slot (34) in the first component (30).

Abstract: A gas turbine engine mounting arrangement for attaching a gas turbine engine to a support structure, such as a pylon of an aircraft, comprises a main mounting member adapted to interconnect the engine with the pylon and transmit loads therebetween under normal engine operating conditions, and an auxiliary mounting member which is capable of interconnecting the engine with the pylon and transmitting loads therebetween in the event of failure of the main mounting member, the auxiliary mounting member being arranged to be substantially unloaded under normal engine operating conditions. The main mounting member includes a first primary load transmission means for transmitting vertical loads between the engine and the pylon and a second primary load transmission means for transmitting thrust and lateral loads between the engine and the pylon.

Abstract: A component such as a turbine blade for a gas turbine engine has a cooling arrangement comprising a supply passage 18 within the blade from which extend cooling passages 28 of a first array which open at discharge openings 29, for example at a trailing edge of the blade. Cooling passages 30 of a second array extend into the blade from discharge openings 31, and intersect the passages 28. The passages 30 terminate short of the supply passage 18. As a result of this arrangement, the limiting flow area for cooling air is defined by the cooling passages 28 of the first array, and is not affected by the accuracy with which the cooling passages 30 of the second array intersect the cooling passages 28 of the first array.

Abstract: A compliant seal provides a seal between an upstream region and a downstream region. The seal includes: a seal pack carrier defining a slot, the seal pack carrier having an upstream face and a downstream face; and a seal pack slideably mounted within the slot, the seal pack having an upstream face and a downstream face. The seal pack carrier and seal pack define a high-pressure plenum which abuts the downstream side of the seal pack, and which can be pressurized to apply a force to the seal pack in the upstream direction.

Abstract: A nozzle guide vane for a gas turbine comprises at least one aerofoil having a leading edge section provided with at least one internal cavity for conveying cooling fluid through the said leading edge section, and a plate like wall section extending from the leading edge section to provide a continuous surface between the aerofoil leading edge section and the aerofoil trailing edge on the suction side of the aerofoil.

Abstract: In prop fan and contra fan gas turbine engines particularly utilised with regard to pusher configurations towards the aft of an aircraft, there is a significant problem with regard to debris and bird strikes resulting in particulate matter which may damage the engine thrust core. By providing an inlet rotor which fragments and creates a centrifugal aspect to the inlet flow, particulate matter can be directed to a bypass chute normally in the form of an annular section extending into a number of chute exits. In such circumstances, the particulate matter is removed continuously from the inlet flow and the chutes are normally angled to project any particulate matter towards propellers of the engine at robust positions.

Abstract: A sealed assembly comprising two bodies and an elastomeric seal therebetween wherein the seal comprises an internal web that is aligned in the general direction of a shear force between the two bodies.

Abstract: A method of operating a gas turbine engine having a turbine and a compressor connected via a shaft, a main fuel supply line for supplying fuel to a combustor that is positioned to release expanding hot gases to the turbine, the engine further including a starter/generator connected to the shaft via a gearbox assembly, the method is characterised the step of during engine start up fuel is circulated in a re-circulating fuel circuit positioned on the main fuel supply line and which a first fuel/oil heat exchanger, for cooling the oil, and a fuel accumulator.

Abstract: Casings are utilized within gas turbine engines in order to provide both an environmental containment for the engine core as well as inhibit release of debris should engine components fragment and fail in service. Traditionally, casings have taken the form of a solid containment shield to prevent debris and object release on percussive impingement with the casing. Such an approach avoids the uncertainties with respect to flap rupture propagation of the casing in use. However such casings are relatively thick and therefore provided a severe weight penalty in aircraft. By providing a casing which has a relatively thinner containment shield and an additional, where required, catch layer rupture of the containment shield can be allowed whilst the catch layer prevents rupture propagation and therefore aperture development to a sufficient size to allow the debris to pass completely through the casing at all or with sufficient energy to cause damage.

Abstract: A centrifugal gas/liquid separator for location in a liquid reservoir comprises a generally cylindrical wall defining a separation chamber having a closed end, an open end, an inlet in the cylindrical wall for supplying a gas/liquid mixture into the separation chamber, and a gas outlet located externally of the separation chamber for discharging gases from the separator. The separator defines at least one liquid flow path for conveying separated liquid from the open end of the separation chamber into a reservoir, and at least one gas flow path for conveying separated gases from a radially inner region of the open end of the separation chamber, externally of the separation chamber, to the gas outlet. The separator is particularly suitable for separating air/oil mixtures in an oil system of a gas turbine engine.

Abstract: A compliant seal assembly having a seal pack carrier having an upstream face and a downstream face that defines a slot, and a seal pack having an upstream face and a downstream face slideably mounted within the slot. The seal pack carrier and the seal pack contact each other and form a high-pressure plenum and a low-pressure plenum. The compliant seal assembly also includes a first passage with a first and second opening and a second opening with a first and second opening. The first opening of the first passage is located at the upstream face of the seal pack carrier, and the second opening of the first passage communicates with the high pressure plenum. The first opening of the second passage is located at the downstream face of the seal pack carrier, and the second opening of the second passage communicates with the low-pressure plenum.

Abstract: A nacelle assembly 40 adapted for mounting on a ducted fan gas turbine engine 20 comprising a generally annular body 46 having an air inlet 42 and an air outlet 44, the generally annular body 46 encircling a region of the engine 20 when working in operative association with the engine 20 and has a first attachment means 48 to a rigid member 58 and a second attachment means 52 to a casing assembly 34 on the engine 20 wherein the second attachment means 52 is frangible.

Abstract: Means for cooling a bearing assembly supporting a rotor stage of a gas turbine engine after engine shutdown. The engine comprises a combustion section, a compressor for the delivery of air to the combustion section, and a bearing assembly supporting a rotor stage. The means for cooling a bearing assembly comprises a means operable to generate a signal representative of turbine duct temperature immediately prior to engine shutdown, a means for determining the duration for cooling after engine shutdown as a function of the signal representative of turbine duct temperature, and the compressor operable as a cooling means to deliver cooling air to the rotor stage after engine shutdown. Thereby the amount of heat conducted to the bearing assembly is limited such that the temperature of the bearing assembly is limited to below a predetermined temperature.

Abstract: Some aircraft configurations have an engine arrangement comprising engines as part of an aft fuselage. In order to accommodate such engine arrangement positions, wings are rearwardly displaced compared to other aircraft configurations for balance across the fuselage. By creating empennage functions utilising the nacelle of engines as well as flaps to create rudder and elevator functions, it is possible to accommodate larger engine sizes more suitable for noise control with a reduced necessity for designed rearward movement of wings.

Abstract: Sensors (32, 52, 72) for determining a gap between a conductive member (34, 54, 74) such as a blade in a gas turbine engine and a seal segment (31, 51) are known to use capacitive variants in order to create an electrical signal indicative of the gap width. Thermal disparities can create problems with regard to sensor ageing and accuracy. By creating a sensor incorporating a metal rod (33, 53, 74) typically integrally formed or associated with the seal segment (31, 51) and coupled through inductive coupling loops (35, 36; 55, 56; 75) it is possible to create a tuned circuit with a Q value which is more stable and therefore acceptable with regard to producing more accurate results at elevated temperatures with less problems with regard to thermal disparities.

Abstract: A blisk for use in the turbine section of a gas turbine engine comprises a disk around the circumference of which is disposed a plurality of blades in an annular array. The blades are preferably cast separately and then joined, for example by welding, so that the roots form a continuous ring. The remaining volume of the rotor disk is formed of consolidated metal powder by a hot isostatic process. Extending a short distance above each blade root is a shank carrying a platform and the blade airfoil section. The dimensions of the platforms in the circumferential direction are such that they co-operate to form a plenum chamber encircling the periphery of the rotor disk. The blades are cast with internal cooling passages access to which is gained from the plenum through orifices in the sides of the blade shanks. Thus, in use, cooling air may be passed across at least one face of the blisk into the plenum from where it enters the blade cooling passages.

Abstract: A duct comprising an inner casing spaced apart from an outer casing and which also comprises a number of interfaced duct sections must be assembled in such a way to prevent relative redial movement between the casings and thereby inhibit buckling. The present invention is a duct which utilises abutment members which longitudinally extend from each of the inner walls across the interface of the duct sections. The abutment members are radially spaced apart in normal use but are configured such that substantially relative radial movement of the inner and outer walls is prevented when the overlapping members abut.

Abstract: In a method of applying a constrained layer damping material 18 to a component 16, the material 18 is placed on the component 16, and pressure is applied over substantially the entire area of the material 18 for not less than 5 minutes and not more than 8 hours, the pressure being not less than 34 kPa, and the temperature being maintained at not less 80° C. and not more than 180° C. for the duration of the application of pressure.

Abstract: It is known that determination of bleed valve activation in a gas turbine engine can be difficult unless the engine is maintained at a steady idle state for comparison between that state and effects of activation of the bleed valve. Furthermore, specific test activation of bleed valves increases wear and tear on those valves. By sensing a flow pressure response signal and then through appropriate averaging and processing through a non-linear filter, it is possible to identify bleed valve activation by a target signal response exceeding a threshold indicative of such bleed valve activation.

Abstract: A sealed joint for joining male and female parts which is tolerant of relative displacement of the parts. Either of the parts may carry a sealing member that sealingly contacts a sealing surface provided on the other part. Either of the parts may carry a support member that is in load communication with a support surface provided on the other part. The sealing member and support member are spaced apart in the direction of relative displacement such that over the range of relative displacement the sealing member remains in contact with the sealing surface and the support member remains in contact with the support surface.