Abstract: A gas turbine engine comprising: a bypass duct having a bypass nozzle; an engine core having a core nozzle; and, a mixer duct defined by a mixer fairing and having a mixer nozzle, wherein the mixer duct is arranged to receive an airflow from the bypass duct through a mixer duct inlet and an airflow from the engine core, when in use, and the geometry of the mixer duct is selectively adjustable by moving the mixer fairing relative to the bypass duct and engine core in use.

Abstract: A cooling system for a gas turbine engine. The system includes a fuel air heat exchanger with a fuel passage that is in thermal contact with an engine cooling air passage. The system further includes a fuel deoxygenator located upstream of the fuel air heat exchanger and configured to deliver deoxygenated fuel to the fuel air heat exchanger fuel passage. The system also includes a valve configured to moderate engine cooling air flow to the engine cooling air passage.

Abstract: The invention concerns an aircraft propulsion control system in which a gas turbine engine has an actuable flow opening for control of flow to or from a portion of the engine. One or more sensor is arranged to sense a condition indicative of vapor trail formation by the exhaust flow from the engine. A controller is arranged to control actuation of the flow opening so as to reduce the efficiency of the engine upon sensing of said condition by the one or more sensor. In one example, the flow opening is a variable area fan nozzle.

Abstract: This invention relates to a method and apparatus for controlling power distribution in an electrical aircraft propulsive system having at least one electrical propulsion unit which includes a plurality of rotatable blades, each blade having an adjustable pitch; a pitch adjusting mechanism for adjusting the pitch of the blades; at least one electrical machine electrically connected to the electrical propulsion unit so as to provide electrical power when in use; and, a control system, the method comprising the steps of: determining the required propulsion; determining whether the propulsive units are delivering the required propulsion; and, adjusting the pitch angle of the blades of at least one propulsive unit so as to increase or decrease the propulsion provided by that propulsive unit.

Abstract: There is disclosed a method of operating a gas turbine engine of a type having a compressor section, a combustor section, and a turbine section arranged in flow series. The method involves the steps of: providing a supply of cryogenic liquid fuel; vaporising the cryogenic liquid fuel to produce a gaseous fuel; expanding said gaseous fuel in at least one fuel turbine external to the engine's turbine section; and thereafter directing said expanded gaseous fuel into the engine's combustion section for combustion therein. A related gas turbine arrangement configured for implementation of the method is also disclosed.

Abstract: This invention relates to an aircraft comprising: a first propulsive unit having a first fan with an axis of rotation; and a second propulsive unit local to the first propulsive unit, the second propulsive unit having a second fan with an axis of rotation, wherein the rotational axis of the first fan is proximate to the surface of the aircraft relative to the rotational axis of the second fan such that the first fan ingests boundary layer air when in use.

Abstract: A gas turbine engine comprising: a bypass duct having a bypass nozzle; an engine core having a core nozzle; and, a mixer duct defined by a mixer fairing and having a mixer nozzle, wherein the mixer duct is arranged to receive an airflow from the bypass duct through a mixer duct inlet and an airflow from the engine core, when in use, and the geometry of the mixer duct is selectively adjustable by moving the mixer fairing relative to the bypass duct and engine core in use.

Abstract: A gas turbine engine propulsion system in which a first propulsive unit has a core engine and a first low pressure turbine arranged to be driven by combustion products from the core engine. The first propulsive unit also has a first fan rotor and a first fan shaft drivingly connecting the first turbine and the first fan rotor. The propulsion system also has a further turbine arranged in flow series with the first turbine and a second propulsive unit spaced from the first propulsive unit. The second propulsive unit has a second fan rotor driven by the rotational output of the further turbine. The further turbine may be located in the second propulsive unit and may be in fluid communication with the first turbine via an inter-turbine duct.

Abstract: The invention concerns an aircraft propulsion control system in which a gas turbine engine has an actuable flow opening for control of flow to or from a portion of the engine. One or more sensor is arranged to sense a condition indicative of vapour trail formation by the exhaust flow from the engine. A controller is arranged to control actuation of the flow opening so as to reduce the efficiency of the engine upon sensing of said condition by the one or more sensor. In one example, the flow opening is a variable area fan nozzle.

Abstract: A cooling system for a gas turbine engine (10). The system is comprises a fuel air heat exchanger (78) comprising a fuel passage (80) in thermal contact with an engine cooling air passage (82). The system further comprises a fuel deoxygenator (72) located upstream of the fuel air heat exchanger (78) configured to deliver deoxygenated fuel to the fuel air heat exchanger fuel passage (80). The system includes a valve (84) configured to moderate engine cooling air flow to the engine cooling air passage (82).

Abstract: Within a power generating arrangement 1 it is typically necessary to provide a coupling with an electrical power distribution cable 5. Previously this was sometimes achieved through use of brush gear and slip rings but such arrangements are subject to regular replacement for wear, maintenance and also there is a requirement to control humidity about the brush gear coupling. Alternatively, a system allowing an amount of rotation, limited by cable wind up was used. By providing a transformer in which windings 15, 16; 36, 37 are physically separated by an air gap 14, 39, but still induce voltage from variation in the magnetic flux, it is possible to create a power generating transfer transformer which can be rotated while driving electrical current for an external load.

Abstract: Power generating apparatus (10) including a cable (12) which rotatably mounts a plurality of power units (14). The power units (14) include wind power turbines (46) for producing power from the wind as the power units (14) fly in the sky whilst connected to the cable (12).

Abstract: A rotor disc (15) has an axially enlarged hub portion (18) with a bore (20) through which a turbine shaft (19) extends in a coaxial, radially spaced apart relationship, the annular gap between the hub portion (18) and the shaft (19) receives a flow of temperature regulating fluid. The shaft (19) is provided with axially extending elongate projections (22) to increase the turbulence and relative velocity of the temperature regulating fluid adjacent the projections (22).