|astronautix.com||N1 Nuclear AF|
A variant of the first alternative considered in the 1962 nuclear N1 study. This was a 'high thrust' version of the Type A engine - apparently with higher propellant rate, lower specific impulse, and lower engine weight. Due to the very low density of the enormous liquid hydrogen upper stages, these immense vehicles would have been very ungainly (and had interesting stress problems during ascent!)
LEO Payload: 300,000 kg. to: 220 km Orbit. at: 51.6 degrees. Payload: 27,100 kg. to a: lunar surface trajectory. Liftoff Thrust: 3,600,000 kgf. Total Mass: 2,500,000 kg. Core Diameter: 17.0 m. Total Length: 200.0 m.
At the end of 1961 the Glushko and Bondaryuk bureaux completed their draft projects on nuclear thermal engines for space vehicle upper stages. It was decided to continue work on development of an engine in the 30 to 40 tonne thrust range. In the following year Korolev was asked to study application of such engines, followed by a specific demand in May 1963 from the Scientific-Technical Soviet for specific recommendations. For a Mars expedition, it was calculated that the AF engine would deliver 40% more payload than a chemical stage, and the V would deliver 50% more. But Korolevís study also effectively killed the program by noting that his favoured solution, a nuclear electric ion engine, would deliver 70% more payload than the Lox/LH2 stage. Further investigation of nuclear thermal stages for the N1 does not seem to be pursued. Bondaryuk and Glushko turned to Chelomei and his competing UR-700 rocket for future application of such stages.