The original engine contained a single stage fan driven by a 4-stage low pressure (LP) turbine, supercharging a 14-stage HP compressor driven by a 2-stage high pressure (HP) turbine, with an annular combustor.
The initial powerplant consisted of a solitary axial blower propelled by a four-stage low-pressure impeller, augmenting a fourteen-stage high-pressure compressor powered by a two-stage high-pressure turbine featuring an annular combustion section.