Patent attributes
The described accessory drive system for a gas turbine engine includes a gearbox driving a plurality of accessories including a cabin air compressor to provide cabin air and an engine starter to start the gas turbine engine. An electrical power supply separate from a main electrical power supply of the gas turbine engine is electrically coupled to the accessories. A clutch selectively engages an output of the gas turbine engine to mechanically couple the output to the gearbox. The clutch operates between an electrical drive state where it disengages from the output and only the electrical power supply provides electrical power to the cabin air compressor and the engine starter, and a mechanical drive state where the clutch engages the output and the gearbox drives at least one of the accessories.
