A type of turbine engine that does not (directly) propel an aircraft, but, rather, provides power for other systems.

A turboshaft engine, like a , is a type of turbine engine that extracts power from the turbine(s) rather than using the engine's exhaust for thrust; unlike a turboprop, a turboshaft does not use the turbine to drive a propeller (at least not directly; most types of have main rotors powered by turboshaft engines via a complicated transmission and mast assembly), but, rather, to power other aircraft systems. Many aircraft use a turboshaft engine as an , which can power the aircraft's s and electrical busses if the main engines aren't turned on (for instance, when the aircraft is parked at the gate), and can provide compressed air for starting the engines.

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