Patent ID: 7418821

Claim:
An aircraft comprising a power system and a gas turbine engine, the engine including a first compressor and a second compressor of higher pressure than the first compressor; a starter motor; a first energy transfer machine; and a second energy transfer machine, wherein the engine also includes first drive means which connects the first compressor to the starter motor and the first energy transfer machine; second drive means which connects the second compressor to the second energy transfer machine; and machine connection means for interconnecting the first energy transfer machine and the second energy transfer machine, and that is also arranged to connect the second energy transfer machine to the aircraft power system, the machine connection means being arranged to be selectively either in a first condition, during start-up of the gas turbine engine, interconnect the first energy transfer machine and the second energy transfer machine to drive the second compressor, or in a second condition connect the second machine to the aircraft power system, and wherein the first drive means includes a gearbox which connects to the starter motor and the first energy transfer machine.