S2.1150

Isayev Nitric acid/Amine rocket engine. Burya booster. Out of production. First flight 1957. Engines developed from R-11 S2.253 engine.

Booster engine for Burya missile. Two used to boost ramjet second stage to ignition conditions. Engines developed by Isayev from R-11 S2.253 engine. Early Buryas had S2.1100 engine. Two thrust levels. 671,20 / 477 kN sea-level. While Glushko found the nitric acid/kerosene combination acceptable for the Buran cruise missile / RD-212 application, Isayev turned to a different combination for his booster for the competing Burya missile booster. Isayev tested nitric acid with many fuels, including amines, before finally selecting hydrazine. Cluster testing of Isayev's engine was also conducted with TM-185 turpentine. Stand tests began with four prototypes in March 1957 at NII-229 Zagorsk.

Chambers: 4. Engine: 650 kg (1,430 lb). Chamber Pressure: 53.00 bar. Thrust to Weight Ratio: 105.29.