The Rolls-Royce Crecy was an unusual British experimental two-stroke, 90-degree, V12, liquid-cooled aero-engine of 1,536 cu.in (26 L) capacity, featuring sleeve valves and direct petrol injection. Initially intended for a high-speed "sprint" interceptor fighter, the Crecy was later seen as an economical high-altitude long-range powerplant. Developed between 1941 and 1946, it was among the most advanced two-stroke aero-engines ever built. The engine never reached flight trials and the project was cancelled in December 1945, overtaken by the progress of jet engine development.