Abstract: An engine for an aircraft has an engine core having a turbine, a compressor, and a core shaft connecting the turbine to the compressor; a fan located upstream of the engine core, the fan having a plurality of fan blades; and a gearbox. The gearbox is arranged to receive an input from a gearbox input shaft portion of the core shaft and to output drive to the fan so as to drive the fan at a lower rotational speed than the core shaft. The gearbox is an epicyclic gearbox and has a sun gear, a plurality of planet gears, a ring gear, and a planet carrier. The planet carrier and the gearbox support each have a torsional stiffness, and a carrier to gearbox support torsional stiffness ratio is greater than or equal to 2.3.

Abstract: A gas turbine engine includes a fan mounted to rotate about a main longitudinal axis; an engine core, including a compressor, a combustor, and turbine coupled to the compressor through a shaft; and reduction gearbox; wherein the compressor includes a plurality of stages, each stage including a respective rotor and stator, a first stage of the plurality of stages being arranged at an inlet and including a first rotor with a plurality of blades; each blade extending chordwise from a leading edge to a trailing edge, and from root to tip for a span height, wherein 0% of the span height corresponds to the root and 100% of span height corresponds to tip; wherein a ratio of a leading edge radius of each of the plurality of first rotor blades at 0% span height to a minimum leading edge radius is comprised between 1 and 1.50.

Abstract: A method of manufacturing a fan case assembly for a gas turbine engine, the fan case assembly comprising a fan case and a fan liner, wherein the method comprises: providing a mounting ring configured to extend about an inner circumference of the fan case; providing a gasket at an axial end of the mounting ring, wherein the gasket extends around the inner circumference of the fan case; providing the fan liner at the axial end of the mounting ring with the gasket, wherein the fan liner extends around the inner circumference of the fan case; and heating the fan case assembly so as to cure a resin provided between the fan case and fan liner, wherein the heating causes the mounting ring to expand radially relative to the fan case such that the gasket is brought into engagement with the fan case and unwanted migration of resin away from between the fan case and fan liner is restricted.

Abstract: A bleed valve system comprises a duct, featuring a central longitudinal axis and allowing a main flow of fluid to pass from a first environment at a first static pressure to a second environment at a second static pressure along a bleed direction, a valve comprising a valve member arranged within the duct between the first and second environments and movable to partially obstruct the duct and deviate the main flow of fluid to direct at least a part of it towards a portion of an internal wall of the duct; and an ejector, arranged within the duct, downstream of the valve member and offset from the central longitudinal axis in correspondence of said portion of the internal wall, adapted to supply an additional flow of fluid within the duct to accelerate the main flow of fluid and reduce the second static pressure.

Abstract: The present disclosure relates to a rotor assembly for a gas turbine engine, the rotor assembly comprising a first rotor stage having a first disc portion with a peripheral first rim portion and a second rotor stage, the second rotor stage having a second disc portion with a peripheral second rim portion. The second rotor stage is axially adjacent and downstream of the first rotor stage and the second rim portion has an axial extension extending towards the first rim portion such that the axial extension of the second rim portion defines a rotor drum cavity between the first and second disc portions. The second rotor stage further comprises a drive arm extending within the drum cavity to the first disc portion, the drive arm being connected to the first disc portion by at least one connector. The drive arm divides the drum cavity into radially outer rim cavity portion and a radially inner main cavity portion.

Abstract: A ceramic matrix composite (CMC) component is provided that includes: a CMC body in which an environmental protection layer is completely embedded within a CMC material of the CMC body, the environmental protection layer comprising a ceramic that has a higher impact and/or environmental resistance than the CMC material. Methods for manufacturing the CMC component are also provided.

Abstract: A system for supplying lubricant to a component of a gas turbine engine having a fan shaft is provided. The system includes a pump drivably couplable to the fan shaft for pumping lubricant to the component. The pump includes an inlet for receiving lubricant from a lubricant source, an outlet for outputting lubricant to the component and a swashplate movable between at least a first position and a second position. The system also includes a swashplate actuator for actuating the swashplate between the first position and the second position according to whether the fan shaft is rotating in a forward direction or a reverse direction opposite to the forward direction.

Abstract: A planetary gearing includes a sun gear rotating about a rotation axis and driven by a sun shaft; planet gears driven by the sun gear, each planet gear having an axially forward face side and an axially rearward face side; a ring gear engaging the planet gears; and planet slide bearing pins, wherein respectively one planet slide bearing pin is arranged inside a planet gear forming a lubricated journal bearing. At an axially forward face side and/or axially rearward face side, each planet gear forms a recess that extends inside the planet gear starting from the face side, and the planet slide bearing pins respectively form one crowning at their abutment surface such that their outer diameter decreases from a maximum outer diameter to at least an axial end of the abutment surface and has a minimum at the axial end.

Abstract: A forced air convection apparatus and method for cooling turbomachines is provided. The forced air convection apparatus for cooling a turbomachine, the apparatus comprising: a duct assembly having one or more outlets which are removably joinable to one or more corresponding air intakes of the turbomachine, and further having one or more inlets which are removably joinable to one or more corresponding exhausts of the turbomachine to enable closed loop recirculatory airflow through the turbomachine and the duct assembly and back to the turbomachine; and an air handling system having a blower arranged to blow air from the one or more inlets of the duct assembly to the one or more outlets of the duct assembly, and further having a heat exchanger configured to cool the air flowing through the duct assembly.

Abstract: An aircraft cabin blower system includes a transmission configured to receive mechanical power from a gas turbine engine in the form of a first transmission input; and an electrical circuit including a first electrical machine, a second electrical machine, and power management system, wherein, when operating in a blower mode, the first electrical receives mechanical power from the gas turbine engine and act as a generator to provide electrical power to the power management system, and the second electrical machine acts as a motor providing mechanical power to the transmission in the form of a second transmission input, the second electrical machine being driven by electrical power from the power management system. The transmission's output drives a cabin blower compressor when operating in the blower mode, a speed of the output of the transmission being determined by a function of a speed of the first and second transmission inputs.

Abstract: A nickel-base superalloy includes essentially, by weight: 14.75 to 26.5 percent cobalt, 4.1 to 4.65 percent aluminium, 1.1 to 1.9 percent titanium, 3.85 to 6.3 percent tantalum, 1.2 to 2.55 percent niobium, up to 0.07 percent boron, up to 0.06 percent carbon, up to 14.0 percent chromium, up to 1.0 percent iron, up to 1.0 percent manganese, up to 4.2 percent molybdenum, up to 0.5 percent silicon, up to 4.9 percent tungsten, and up to 0.1 percent zirconium, the balance being nickel and incidental impurities; wherein the overall concentration in the alloy of aluminium, titanium, tantalum, and niobium is from 13 to 14 atomic percent and the atomic ratio of aluminium to titanium is from 4.625:1 to 6.333:1.

Abstract: An auxiliary oil supply apparatus for a rotating device (50, 51), the rotating device comprising a primary oil supply (52), a rotating component (50) and a static component (51) situated radially outwardly of a centre of rotation of the rotating component (50) and arranged to collect oil (58) held radially outwardly from the rotating component (50) as the rotating component rotates. The auxiliary oil apparatus comprises a scoop (56) associated with the rotating component (50) and is responsive to a change in a known parameter to move between a first position in the static component (51) to a second position between the static component (51) and the centre of rotation.

Abstract: An air swirler arrangement comprises a coaxial arrangement of an inner and an outer air swirler passage. Each air swirler passage comprises a radial flow swirler. Air swirler arrangement comprises a coaxial arrangement of first, second and third members. Second member has radially extending upstream portion spaced axially from first member and a convergent portion. Third member has a radially extending upstream portion spaced axially from the upstream portion of second member and a radially inner surface having convergent and divergent downstream portions and a radially outer surface having a divergent downstream portion. First, second and third members the vanes of the radial flow swirlers is a monolithic structure. Plurality of circumferentially spaced passages are provided within the third member and each passage has an inlet in the surface and an outlet arranged to direct fluid onto the divergent portion of the surface or the surface of the third member.

Abstract: A nozzle for a fuel injector of a gas turbine engine, the nozzle having an insulating air gap adjacent a conduit for carrying fuel, the air gap formed between a pair of concentrically arranged annular walls, wherein the pair of annular walls are arranged to move independently to accommodate differential thermal expansion, the nozzle further including: a channel extending circumferentially around a surface a first of the pair of annular walls, facing a second of the pair of annular walls; and a sealing member received in the channel, to close the insulating gap.

Abstract: A gas turbine engine comprising a planetary gear train, and a core engine casing. The gear train has a ratio of greater than approximately 3.0, with an input to the gear train being operatively connected to the compressor section, and an output from the gear train being operatively connected to the fan. The core engine casing encloses the compressor section and the turbine section. The fan has a diameter F, and the core engine casing has a diameter C. The core engine casing diameter C varies along an axial length of the core engine casing, and a ratio (C/F) of the core engine casing diameter C to the fan diameter F is within the range 0.2<(C/F)<0.4, along an axial length of the core engine casing.

Abstract: A gas turbine engine has a nacelle providing an external skin of the engine, a casing structure radially inwards of the external skin and providing an outer surface of an air flow duct of the engine, and plural engine components located in the bay formed between the casing structure and the nacelle. The components are part of either a first set of components or a second set of components. The components of the first set are all the components from the bay which are potential ignition sources, and the components of the second set are all the remaining components from the bay. The engine further has a container located in the bay, the container being fireproof capable of withstanding the application of heat by a standard flame for 15 minutes and the container containing the components of the first set.

Abstract: A method determines a generator system load and/or rotor angle. The generator system has a generator with a generator terminal outputting electrical power generated by the generator, a transformer and a point of common coupling, PCC, terminal. The transformer is between the generator and PCC terminals. The method includes: determining the generator field current; determining the output voltage, the output current and the power factor and/or angle of the output voltage and output current from the generator terminal, and determining the load angle of the generator system, output voltage from the generator terminal, output current from the generator terminal and the power factor and/or angle; and/or determining the output voltage, the output current and the power factor and/or angle of the output voltage and output current, and determining the rotor angle of the generator system, output voltage, output current from the PCC terminal and the power factor and/or angle.

Abstract: The present disclosure relates to a geared gas turbine engine for an aircraft. Example embodiments include a gas turbine engine for an aircraft including: an engine core having a turbine, a compressor, and a core shaft connecting the turbine to the compressor; a fan located upstream of the engine core, the fan having a plurality of fan blades; and a gearbox that receives an input from the core shaft to drive the fan at a lower rotational speed than the core shaft, the gearbox having a gear ratio of around 3.4 or higher, wherein the gas turbine engine is configured such that a jet velocity ratio between a first jet velocity exiting from a bypass duct of the engine and a second jet velocity exiting from an exhaust nozzle of the engine core is within a range from around 0.75 to around 0.82.

Abstract: There is disclosed a blade for a gas turbine engine comprising an asymmetrical blade root.

Abstract: A louvre offtake arrangement for a gas turbine engine includes a first duct, where a primary flow flows; a second duct, defining an offtake, connected to the first duct at an inlet; and a plurality of louvres arranged at the inlet. At least one louvre protrudes from the second duct into the first duct to divert part of the primary flow towards the second duct.