Patent attributes
An aircraft capable of operating at a variety of speeds includes a power plant and an auxiliary turbine. The auxiliary turbine can be a ram air turbine used to expand and cool an airflow and provide work. The cooled airflow from the auxiliary turbine can be used in a heat exchange device such as, but not limited to, a fuel/air heat exchanger. In one embodiment the cooled airflow can be used to exchange heat with a compressor airflow being routed to cool a turbine. Work developed from the auxiliary turbine can be used to power a heating device and rotate a device to add work to a shaft of the aircraft power plant. In one form the aircraft power plant is a gas turbine engine and the work developed from the auxiliary turbine is used to heat a combustor flow or to drive a shaft that couples a turbine and a compressor.
