Abstract: The present disclosure provides a podded engine adaptor configured to secure a podded engine to an aircraft, comprising: an airframe mounting interface configured for attachment to an airframe of an aircraft; an engine mounting interface configured for attachment to an engine; wherein the podded engine adaptor is configured to be attached to an engine at the engine mounting interface and to an airframe of the aircraft at the airframe mounting interface, so as to indirectly couple an engine to the aircraft via the podded engine adaptor.

Abstract: A coating system includes a bond layer including CoNiCrAlY; a thermal barrier layer at least partially disposed on the bond layer and including yttria stabilised zirconia; a mesh layer connecting the thermal barrier layer to the bond layer and including CoNiCrAlY; and an abradable layer disposed on the thermal barrier layer and including magnesium spinel. The mesh layer includes a plurality of cells connected to each other and is at least partially embedded in the thermal barrier layer. Each cell defines a cell opening therethrough and the cell opening of each of the plurality of cells at least partially receives the thermal barrier layer therein. The abradable layer and the thermal barrier layer are at least partially removable from the mesh layer and the bond layer without damaging them.

Abstract: A computer-based control system for a gas turbine engine includes: a controller including control logic, the controller obtains a set of inputs formed by measurements of one or more process variables and values of one or more engine operation set points, and the control logic determines one or more process command values gas turbine engine operation in response to the set of inputs; and an event detection unit obtaining further measurements of one or more process variables and determine whether an abnormal event has occurred based on the further measurements of one or more process variables. The controller also updates the tuning variables using an event accommodation data array, a given tuning variable being changed in response to detection of a given abnormal event when the respective element in the event accommodation data array is assigned an intervention value.

Abstract: A method of operating a gas turbine engine having an engine core having a turbine, a compressor, a combustor arranged to combust a fuel, and a core shaft connecting the turbine to the compressor; a fan located upstream of the engine core; a fan shaft; a gearbox that receives an input from the core shaft and outputs drive to the fan via the fan shaft; a heat exchange system having at least one fuel-oil heat exchanger arranged to transfer heat to the fuel; and a fuel pump arranged to deliver the fuel to the combustor, wherein the fuel pump is located downstream of the at least one fuel-oil heat exchanger. The method comprises controlling the heat exchange system so as to raise the fuel temperature to at least 135° C. on entry to the combustor at cruise conditions.

Abstract: A method of operating a gas turbine engine including an engine core and turbine, a compressor, a combustor arranged to combust a fuel, and a core shaft connecting the turbine to the compressor; a fan located upstream of the engine core; a fan shaft; a main gearbox that receives an input from the core shaft and outputs drive to the fan via the fan shaft, the main gearbox including gears and journal bearings; a recirculating lubrication system arranged to supply oil to lubricate the gears and journal bearings, the lubrication system including a first oil tank arranged to supply oil to the gears and journal bearings and a second oil tank arranged to supply oil to the journal bearings only. The method includes, at cruise conditions: transferring 200-600 kJ/m3 of heat to the fuel from the oil through the heat exchange system so as to control the oil temperature.

Abstract: A gas turbine engine has a compression system blade ratio defined as the ratio of the height of a fan blade to the height of the most downstream compressor blade in the range of from 45 to 95. 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: An estimation of junction temperatures of transistors in power electronics converter.

Abstract: A battery pack includes: a plurality of cylindrical battery cells, each one of the plurality of cells having a cylindrical outer cell wall that extends in a z-direction between opposed first and second ends of the cell; a carrier structure that locates the battery cells relative to one another and arranges them in an array in an x-y plane perpendicular to the z-direction; and a plurality of barriers for preventing propagation of thermal runaway between cells of the array, each one of the plurality of barriers forming a barrier wall that surrounds a group of one or more of the cells. A gap is defined between the barrier wall of each respective barrier and the outer cell wall of each of the respective one or more cells enclosed by the respective barrier.

Abstract: A method of thrust control for an airbreathing jet engine includes obtaining a demanded thrust setting, a value of static pressure at a first axial location of a combustion chamber of the airbreathing jet engine and a value of static pressure at a second axial location of the combustion chamber of the airbreathing jet engine. The second axial location is downstream of the first axial location. The method also includes obtaining a ratio of the value of static pressure at the first axial location of the combustion chamber to the value of static pressure at the second axial location of the combustion chamber; and controlling a fuel flow rate of the airbreathing engine based at least in part on the demanded thrust setting and the ratio of the value of the static pressure at the first axial location to the value of the static pressure at the second axial location.

Abstract: Battery packs, which may be used in vehicles, include: a plurality of battery cells; one or more flow control devices; and sensing and control circuitry configured to: measure one or more parameters indicative of an onset of thermal runaway of one or more of the plurality of cells; determine, based on a change in one or more of the measured parameters, that one or more of the plurality of battery cells has begun or is at risk of beginning thermal runaway; and activate one or more of the flow control devices in response to the determination. Each of the one more flow control devices is configured to, when activated, direct a flow of fluid past one or more of the plurality of cells to cool the cells and/or carry media vented by one or more of the cells following a thermal runaway event away from the one or more cells.

Abstract: The disclosure relates to estimation of junction temperatures of transistors in a power electronics converter. Example embodiments include a method of estimating a junction temperature of a transistor in a power electronics converter configured to convert between first and second supply voltages, the method comprising: providing a gate switching signal to the transistor; measuring a rate of change of current through the converter during a switching period of the transistor; and outputting an estimated junction temperature of the transistor based on the measured rate of change of current, wherein the rate of change of current is measured while a gate voltage of the transistor is above a gate threshold voltage and a drain-source voltage across the transistor is above a predetermined fraction of the first or second supply voltage whereby the rate of change of current is measured in a linear region.

Abstract: An apparatus for metallurgical heat-treatment includes a solid-oxide electrolyser, a furnace and a heat-exchanger. The electrolyser is arranged to electrolyse water and provide resulting hydrogen to the furnace. A first portion of the hydrogen from the electrolyser is combusted in a combustor to heat the furnace. A second portion provides a treatment atmosphere including hydrogen for the heat-treatment of a metal or metal alloy object. Water vapour output by the combustor is provided to the heat-exchanger which transfers heat within the water vapour to the solid-oxide electrolyser to improve or maintain its efficiency. In contrast to apparatus of the prior art, the apparatus does not produce carbon dioxide at the point of use. By applying waste heat, carried by the water vapour output from the combustor, to the electrolyser, the power consumption of the electrolyser is reduced for a given rate of electrolysis.

Abstract: A computer-implemented method comprising: controlling input of data quantifying damage received by a compressor of a gas turbine engine into a first machine learning algorithm; receiving data quantifying a first operating parameter of the compressor as an output of the first machine learning algorithm; and determining operability of the compressor by comparing the received data quantifying the first operating parameter of the compressor with a threshold.

Abstract: There is disclosed a lay-up apparatus for laying up fibre reinforcement material, the lay-up apparatus comprising a lay-up tool defining a lay-up surface, a placement head having a flexible membrane which is conformable to the layup surface, and a membrane vacuum port extending through the membrane and configured to hold a ply against the membrane when suction is applied through the membrane vacuum port. The placement head is configured to cooperate with the lay-up tool so that when a ply is held against the membrane, an airtight chamber is formed between the membrane and the lay-up tool. The lay-up tool comprises a consolidation vacuum port configured to permit evacuation of the airtight chamber to cause the membrane and ply to move towards the lay-up surface.

Abstract: A method of optimising the performance of combustion equipment of a gas turbine engine includes providing a fuel flow into the combustion equipment via a plurality of fuel injectors circumferentially disposed about a principal rotational axis at a plurality of injector positions; determining a plurality of temperatures of combustion gases at a plurality of circumferential positions downstream of the combustion equipment using a plurality of temperature measurement devices; ranking the plurality of circumferential positions based on the plurality of temperatures of the combustion gases determined using the plurality of temperature measurement devices; and repositioning at least some of the plurality of fuel injectors between the plurality of injector positions based at least on the ranking of the circumferential positions.

Abstract: A fan stage of a ducted fan gas turbine engine has a rotor hub having a principal axis of rotation and a plurality of fan blades having a hub end attached to the hub and extending radially towards a tip end so as to define a blade span dimension. Each blade has a leading and a trailing edge, a chord for a section of the blade being a straight line joining the leading and trailing edges within the section. A difference between a stagger angle in a mid-span region and in the vicinity of the tip end of each blade is greater than or equal to 20°. The fan blades are twisted to a greater extent than conventional between the mid-span and tip end. A camber angle difference between the mid-span region and the tip end may be greater than 30 degrees.

Abstract: An engine for an aircraft includes 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 an epicyclic gearbox and comprises a sun gear, a plurality of planet gears, a ring gear, and a planet carrier on which the planet gears are mounted. The radial bending stiffness of the planet carrier is equal to or greater than 1.20×109 N/m, and/or the tilt stiffness of the planet carrier is greater than or equal to 6.00×108 Nm/rad. A method of operation of such an engine is also disclosed.

Abstract: A gas turbine engine includes an engine core with a combustor; a turbine including turbine blades; a compressor as a source of cooling air for the turbine blades; and an inducer to accelerate and direct the cooling air onto the turbine blades, and a modulating valve to allow or block cooling air flow into a subset of airflow passageways of the inducer; and a fuel management system to provide fuel to the combustor. The fuel management system includes a primary fuel-oil heat exchanger and a secondary fuel-oil heat exchanger through which oil and the fuel flow, to transfer heat between the oil and the fuel. A method of operating the engine includes using the modulating valve to adjust the cooling air flow based on turbine inlet temperature; and transferring 200-600 kJ/m3 of heat to the fuel from the oil in the primary fuel-oil heat exchanger at cruise conditions.

Abstract: A containment structure for a propulsion device, comprising a plurality of laminates arranged in a stack for absorbing projectile impact from the propulsion device, each laminate comprising a multi-ply composite of fibre reinforcement material and matrix material. The plurality of laminates comprises a plurality of primary laminates and a plurality of secondary laminates provided in an alternating arrangement along a stacking direction S of the containment structure. The primary laminates comprise a first fibre reinforcement material and the secondary laminates comprises a second fibre reinforcement material. The first fibre reinforcement material has a higher elongation to failure than the second fibre reinforcement material.

Abstract: A method of generating a maintenance schedule for an aircraft including one or more gas turbine engines powered by an aviation fuel. The method includes: determining one or more fuel characteristics of the fuel; and generating a maintenance schedule according to the one or more fuel characteristics. Also disclosed is a method of maintaining an aircraft, a maintenance schedule generation system and an aircraft.