General Electric GE38

The General Electric GE38 is a gas turbine developed by GE Aviation for turboprop and turboshaft applications. It powers the Sikorsky CH-53K King Stallion as the T408.

Design and development

The GE27 was developed in the early 1980s under the "Modern Technology Demonstrator Engines" (MTDE) program sponsored by the United States Army Aviation Applied Technology Directorate. Sporting a 22:1 pressure ratio, which was a record for single-spool compressors at the time, the GE27 was GE's unsuccessful submission to power the Bell Boeing V-22 Osprey tiltrotor aircraft. The GE27 also had a compressor air flow of 27–28 pounds per second (12–13 kg/s) and a turbine temperature of 2,400–2,500 °F (1,320–1,370 °C; 2,860–2,960 °R; 1,590–1,640 K). The GE27 first ran in late 1984, but it unexpectedly lost the V-22 engine competition to the Allison 501-M80C, which was not a participant in the MTDE program.

In the late 1980s, GE used the GE27 as the basis for the commercial development of turboshafts, turboprops, turbofans, and propfans under the GE38 name. GE formed a 50/50 venture with Garrett (then a division of AlliedSignal) to develop the turbofan variant called the CFE (Commercial Fan Engines) CFE738, which used the GE27's gas generator core. One of a range of advertised GE38 unducted fan (UDF) sizes, the 9,620 lbf (4,360 kgf; 42.8 kN) takeoff thrust GE38-B5 was for a time the baseline engine for the West German-Chinese MPC 75 regional airliner. The GE38 became the T407 military turboprop in partnership with Lycoming Engines for the Lockheed P-7A, with a maximum takeoff power of 6,000 shp (4,475 kW).