Reaction Motors XLR-11
The Reaction Motors XLR-11 (Navy designation Reaction Motors XLR-8 ) is an American liquid rocket engine . It was the first of this type in the USA for use in manned aircraft.
Development began in 1944 at Reaction Motors, Inc. The engine had four combustion chambers that could not be throttled, but could be switched on and off individually in flight. Each of these combustion chambers had a thrust of initially 6.7 kN, so that a total of 26.7 kN could be generated. Later 8.9 kN per combustion chamber was achieved, a maximum of 35.6 kN. The weight was only 96 kg. Liquid oxygen and alcohol were used as fuel .
The first flight of a live XLR11 engine took place in 1946. With this engine, the sound barrier was broken for the first time (with the Bell X-1 ) and for the first time it was flown faster than twice the speed of sound. This could be achieved with the Douglas D-558-II . It was also used on the Republic XF-91 and the Martin-Marietta X-24 .
The last model equipped with this engine was the North American X-15 , which was equipped with two of these engines during the first flight attempts.
