Abstract: The present invention provides a flexible hose for connecting a fuel manifold to a burner of a gas turbine engine. The flexible hose includes a metal convolute tube, an elongate member or members located in grooves formed in the inner surface of the convolute tube, and a pressure-containing sheath outside the convolute tube. The flexible tube has end connectors fluidly-tightly joined to respective ends of the hose for connection at one end of the hose to the fuel manifold of the gas turbine engine, and at the other end of the hose to the burner of the gas turbine engine.

Abstract: A turboshaft gas turbine engine comprises, in fluid flow series, a gas-generator compressor, a combustor, a gas-generator turbine, and a free power turbine. The expansion ratios of the turbines are dependent upon an outlet temperature of the combustor, and an expansion relationship between the turbines is defined as the ratio of expansion ratios of the turbines over a running range of non-dimensional power outputs of the gas turbine engine. A second derivative of the expansion relationship is from 0.6 to 1.0.

Abstract: A gas turbine engine for an aircraft comprises a high-pressure (HP) spool comprising an HP compressor and a first electric machine driven by an HP turbine; a low-pressure (LP) spool comprising an LP compressor and a second electric machine driven by an LP turbine; a combustion system comprising a fuel metering unit; and an engine controller configured to, in response to a change of a throttle lever angle setting indicative of an acceleration event, increase fuel flow to the combustion system by the fuel metering unit, and to operate the first electric machine in a motor mode to increase the HP spool rotational speed and engine core mass flow.

Abstract: A gas turbine engine including: a high pressure turbine, a low pressure turbine, a high pressure compressor coupled to the high pressure turbine by a high pressure shaft, a propulsor and a low pressure compressor coupled to the low pressure turbine via a low pressure shaft and a reduction gearbox; wherein the high pressure compressor defines an average stage pressure ratio at cruise conditions of between 1.25 and 1.35 and consists of 10 or 11 stages; and the high pressure compressor and low pressure compressor together define a core overall pressure ratio at cruise conditions of between 40:1 and 60:1.

Abstract: Aircraft electric power distribution systems and methods of operating aircraft electrical power distribution systems are provided. One such method comprises determining a measure of an electrical power demand of a power and propulsion system of the aircraft; setting a target operating voltage of the aircraft electrical power distribution system based at least in part on the measure of the electrical power demand; and controlling the operating voltage in accordance with the set target operating voltage. In some embodiments the measure of the electrical power is a measure of an operating parameter of a gas turbine engine or propulsor of the aircraft.

Abstract: An oil system for a gas turbine engine and a method of supplying oil to the system. The oil system includes a main oil tank connected by oil lines with a supplementary oil storage tank, which has an actuator, and that are connected to one oil pump for supplying oil to the gas turbine engine. The supplementary oil storage tank is equal in size or larger than a steady state oil gulp of the system. The method includes supplying oil from a main oil tank through a pipe line using an oil pump, detecting the oil level in the oil system and determining if additional oil is required or requires removing using a sensor and an electronic controller, and transmitting a signal to an actuator to supply or remove oil to and from the pipe lines in the oil system from or into a supplementary oil storage tank.

Abstract: A system for providing active flow control in an aircraft having a gas turbine engine. The system includes an environmental control system that includes a cabin blower system having a compressor operable to compress a fluid delivered by a fan section of the gas turbine engine to generate a pressurised fluid for use by the environmental control system. The environmental control system is fluidicly connected to an active flow control system via a fluid supply line, for allowing the pressurised fluid generated by the compressor to be supplied to the active flow control system so that it can be ejected from the aircraft across an exterior surface of a movable control element of the aircraft.

Abstract: A method of automatically determining a flight trajectory of a vertical take-off and landing aircraft having vectorable propulsion can be used to improve flight efficiency. The method includes receiving one or more aircraft flight constraints, inputting the aircraft flight constraints to a trajectory planning algorithm to determine a minimum energy aircraft transition trajectory, and outputting a control schedule to fly the aircraft to along the flight trajectory.

Abstract: Disclosed is an exhaust nozzle for a gas turbine engine, the exhaust nozzle comprising an outer frame extending along a longitudinal direction, a convergent petal pivotably attached to the frame and extending axially downstream and radially inward from the pivot, radially within the frame, and a sealing hinge arrangement between an upstream member and a downstream member of the exhaust nozzle. One of the upstream member or the downstream member defines a cylindrical socket having an opening along a cylinder axis which receives a corresponding cylindrical hinge element the other of the downstream member or upstream member, where the upstream member is defined by the frame and the downstream member is the convergent petal; or the exhaust nozzle further comprises a divergent petal downstream of the convergent petal and pivotably attached to the convergent petal, the upstream member being the convergent petal and the downstream member being the divergent petal.

Abstract: A method of controlling a gas turbine engine including receiving an instantaneous thrust demand for current operation of the engine, determining the inlet flow rate and/or the pressure ratio within the compressor of the engine and determining whether the inlet flow rate and/or the pressure ratio match the working line for the compressor. The angle of one or more vane of the compressor is adjusted according to a closed control loop if the inlet flow rate and/or pressure ratio lie outside said desired range in order to adjust the inlet inflow rate and/or pressure ratio to meet the working line. The fuel flow to the engine combustor is adjusted concurrently in order to meet the thrust demand.

Abstract: A highly efficient gas turbine engine includes the fan of the gas turbine engine driven from a turbine via a gearbox, such that the fan has a lower rotational speed than the driving turbine, thereby providing efficiency gains. The efficient fan system is mated to a core that has low cooling flow requirements and/or high temperature capability, and which may have particularly low mass for a given power.

Abstract: Disclosed herein is a method of automatically determining an operating condition of at least part of a gas turbine engine 10 for an aircraft, the method comprising: measuring one or more gas pressure waves by a gas pressure detector 401, wherein the gas pressure detector 401 is located in the gas turbine engine 10; and automatically determining, by a computing system, an operating condition of at least part of a gas turbine engine 10 in dependence on an output signal of the gas pressure detector 401.

Abstract: A lean burn combustor includes a plurality of lean burn fuel injectors, each including a fuel feed arm and a lean burn fuel injector head with a lean burn fuel injector head tip, wherein the lean burn fuel injector head tip has a lean burn fuel injector head tip diameter, the lean burn fuel injector head including a pilot fuel injector and a main fuel injector, the main fuel injector being arranged coaxially and radially outwards of the pilot fuel injector; and a combustor chamber extending along an axial direction for a length and including a radially inner annular wall, a radially outer annular wall, and a meter panel defining the size and shape of the combustor chamber, wherein the combustor chamber includes primary and secondary combustion zones. A ratio of the combustor chamber length to the lean burn fuel injector head tip diameter is less than 5.

Abstract: An aircraft propulsion system includes a hydrocarbon fuel store, a hydrogen fuel store, an engine system capable of producing thrust by combusting hydrocarbon fuel and/or combusting or oxidising hydrogen fuel, a conveying system to convey hydrocarbon and hydrogen fuel from the fuel stores to the engine system and a control system to control the respective flow rates of the fuel within the conveying system. The control system adapts the fractions of the total fuel energy flow rate to the engine system represented by the hydrocarbon and hydrogen fuel energy flow rates in order to reduce climate warming impact caused by at least one of carbon dioxide, water vapour and condensation trails and/or increase climate cooling impact caused by condensation trails produced by the aircraft propulsion system compared to a dual-fuel propulsion system in which a reserve of hydrocarbon fuel is entirely combusted before any of a reserve of hydrogen fuel.

Abstract: There is disclosed a method of manufacturing a composite component, the method comprising laying-up a plurality of successive plies of composite material to produce a pre-form (12) for the component in a lay-up procedure, wherein a portion of each ply of composite material is heated to at least a threshold temperature of 45° C. during a period of the lay-up procedure.

Abstract: A gas turbine engine that has improved fuel burn provides operability and/or maintenance requirements when installed on an aircraft. The gas turbine engine is provided with a core compressor that includes twelve, thirteen or fourteen rotor stages. The gas turbine engine has a ratio of a core compressor aspect ratio divided by a core compressor pressure ratio is in the range of from 0.03 to 0.09. This results in an optimum balance between installation benefits, operability, maintenance requirements and engine efficiency when the gas turbine engine is installed on an aircraft.

Abstract: A gas turbine engine for an aircraft including: an engine core including a turbine, a compressor, and a core shaft connecting the turbine to the compressor; a fan located upstream of the engine core, the fan including a plurality of fan blades; a gearbox that can receive an input from the core shaft, and can output drive to a fan shaft via an output of the gearbox so as to drive the fan at a lower rotational speed than the core shaft; and a fan shaft mounting structure arranged to mount the fan shaft within the engine, the fan shaft mounting structure including at least two supporting bearings connected to the fan shaft. A fan-gearbox axial distance is defined as the axial distance between the output of the gearbox and the fan axial centreline, the fan-gearbox axial distance being greater than or equal to 0.35 m.

Abstract: A highly efficient gas turbine engine is provided. The fan of the gas turbine engine is driven from a turbine via a gearbox, such that the fan has a lower rotational speed than the driving turbine, thereby providing efficiency gains. The efficient fan system is mated to a core that has low cooling flow requirements and/or high temperature capability, and which may have particularly low mass for a given power.

Abstract: A computer-implemented method comprising: receiving a first signal from a first sensor, the first signal having a first value; receiving a second signal from a second sensor, the second signal having a second value, the first signal and the second signal being measurements of a parameter of a system; receiving a third signal having a third value; determining a first absolute error using the first value, the second value and the third value; and comparing the first absolute error with at least one threshold to determine a signal value. (To be accompanied when published by FIG.

Abstract: A gas turbine engine, in particular an aircraft engine, includes: a turbine connected via an input shaft device to a gearbox device having a sun gear, a planet carrier having a plurality of planet gears attached thereto, and a ring gear, the sun gear is connected to the input shaft device, the planet carrier or the ring gear is connected to a propulsive fan via an output shaft device of the gearbox device, with a rear carrier bearing device radially between the planet carrier and a static structure on the input side of the gearbox device, an inter-shaft bearing system being positioned radially between the input shaft device and the planet carrier of the gearbox device.