Power plant for UAV

摘要

A high efficiency power plant for a UAV with a high pressure ratio gas turbine engine used for low power operation such as loiter speed and a low pressure ratio gas turbine engine used for high power operation. A power turbine receives hot gas flows from the two engines to drive an output shaft. At low power operation, only the high pressure ratio engine is operated. At high power operation, both engines are operated where the exhaust from the high pressure ratio engine is used to drive a turbine of the low pressure ratio engine. A compressor of the low pressure ratio engine supplies compressed air to a combustor that produces a hot gas stream that is passed through the power turbine.