The Tumansky R-11 is a turbojet engine developed in the Soviet Union during the 1950s. It was designed for use in various aircraft, including the Mikoyan-Gurevich MiG-21, a prominent fighter jet. The R-11 is known for its relatively high thrust-to-weight ratio, which contributed to the performance of the aircraft it powered. This engine features a single-spool design and operates on a simple cycle, making it easier to maintain. The R-11 was widely used in military aviation and played a significant role in the development of jet technology during the Cold War era, influencing future engine designs.