General Electric YF120

The General Electric YF120, internally designated GE37, is a variable-cycle afterburning turbofan engine designed by General Electric Aircraft Engines in the late 1980s and early 1990s for the United States Air Force Advanced Tactical Fighter program. It was designed for maximum thrust in the 35,000 pounds-force class, and prototype engines were installed in the two competing demonstrators, the Lockheed YF-22 and the Northrop YF-23. GE chose a variable cycle design to meet the supercruise requirement and used one-piece blisks in the fan and compressor, while the competing Pratt and Whitney F119 was judged cheaper and less risky and was selected to power what became the F-22 Raptor. The YF120 powered both demonstrators to supercruise speeds.