US Patent 7854582 Operation of an aircraft engine after emergency shutdown

A method of emergency operation of an aircraft turbofan engine during an aircraft flight is provided. The engine includes a fan shaft with a fan, and an electric motor/generator mounted for rotation therewith. The method includes shutting down the engine while allowing the engine to windmill, operating the electric motor/generator to rotate the shaft at a determined windmilling speed which is desired for the fan shaft, and operating the engine at the desired windmilling speed for substantially a remainder of the aircraft flight.