Garrett ATF3

The Garrett ATF3 (US military designation F104) is a three-spool turbofan engine developed at the California division of Garrett AiResearch. Due to mergers it is currently supported by Honeywell Aerospace. The engine's design is unusual; the core flow path is reversed twice. Aft of the fan, the axial compressor has five stages, after which the gas path progresses to the aft end of the engine. There, it is reversed to flow through a centrifugal compressor stage, the combustors and then the turbine stages. Beyond this, the flow is then reversed again to exit through the fan bypass duct. All engine accessories are mounted on the aft end of the engine under a tail cone.