alternatehistory.com
RD-270 vs RD-253
Despite eight-hour shifts and exhausting rate of Glushko's work in 1963 it became clear that RD-270 even if ready for 1969 deadline, would not be reliable enough to safe flight. While Soviets never bothered about safest flights (Kuznetsova had 50% chances for survival), death of cosmonauts heading for Moon would be major propaganda defeat for all Eastern Bloc. RD-270 were very pressurized engines with very high specific impulse (Isp) from two circuits of full-flow staged combustion cycle. Many engineers feared hat it could encounter problems that could stopped entire lunar programme! But there was one idea - using sixteen smaller RD-253 engines which were already under construction - first tests were fired on 1963. Orginally intended for Chelomei's UR-500 rocket known as Proton they were quickly adapted to Yangel's R-56 rocket. Sixteen engines required improved onboard computer known as KORD to manage their work as there wer old Soviet saying among aerospace engines: More engines you add, more will fail.
Six RD-253 with its 285 second of specific impulse and 1,470 kN of thrust powered first stage of test Proton rocket launched on July 16th, 1965 during its maiden flight. RD-270 engines entered into spaceflight on January 14th, 1970 when four of them powered R-56 unmanned rocket during tests and were rated as man-able few months later.
Despite eight-hour shifts and exhausting rate of Glushko's work in 1963 it became clear that RD-270 even if ready for 1969 deadline, would not be reliable enough to safe flight. While Soviets never bothered about safest flights (Kuznetsova had 50% chances for survival), death of cosmonauts heading for Moon would be major propaganda defeat for all Eastern Bloc. RD-270 were very pressurized engines with very high specific impulse (Isp) from two circuits of full-flow staged combustion cycle. Many engineers feared hat it could encounter problems that could stopped entire lunar programme! But there was one idea - using sixteen smaller RD-253 engines which were already under construction - first tests were fired on 1963. Orginally intended for Chelomei's UR-500 rocket known as Proton they were quickly adapted to Yangel's R-56 rocket. Sixteen engines required improved onboard computer known as KORD to manage their work as there wer old Soviet saying among aerospace engines: More engines you add, more will fail.
Six RD-253 with its 285 second of specific impulse and 1,470 kN of thrust powered first stage of test Proton rocket launched on July 16th, 1965 during its maiden flight. RD-270 engines entered into spaceflight on January 14th, 1970 when four of them powered R-56 unmanned rocket during tests and were rated as man-able few months later.
- Tal Shiar
- Word Count: 230