Abstract: A fuel injector includes a fuel nozzle configured to issue a spray of fuel from a fuel outlet in a downstream direction along an injection axis. The fuel nozzle defines a main flow passage therethrough. An injection fuel line is in fluid communication with the fuel nozzle to supply fuel to the fuel nozzle. A torch ignitor has a flame outlet opening into the main flow passage of the fuel nozzle for issuing flame into the main flow passage.

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, the first electric machine having a first maximum output power; a low-pressure (LP) spool comprising an LP compressor and a second electric machine driven by an LP turbine, the second electric machine having a second maximum output power; and an engine controller configured to identify a condition to the effect that the LP turbine is operating in an unchoked regime, and, in response to an electrical power demand being between zero and the first maximum output power, only extracting electrical power from the first electric machine to meet the electrical power demand.

Abstract: An engine system comprises first and second electrical generators coupled to lower and higher pressure (LP, HP) shafts respectively of a gas turbine engine. A controller is arranged to receive a signal corresponding to a total electrical power demand P1 and to output control signals to the electrical generators in response thereto such that the first and second electrical generators output electrical powers (1?y)P1 and yP1 respectively when P1?Pm1, where 0.5<y?1 and Pm1 is the maximum electrical output power of the first electrical generator. By satisfying the demand P1 mostly by extraction of electrical power from the first electrical generator when possible, the additional mechanical stress on the gas turbine engine resulting from electrical power extraction is reduced compared to the case where 50% or more of the demand P1 is satisfied by the second electrical generator.

Abstract: A fluidic apparatus for modulating the rate of fuel flow into the combustor of a gas turbine engine. The apparatus includes a fluidic oscillator device (preferably an astable fluidic oscillator, or “flip-flop”) having a supply inlet connected to a fluid fuel source and a pair of outlets one of which is connected to the combustor. The fluidic device operates to output fluid fuel from the outlets alternately, so modulating fuel flow into the combustor.