This created a problem for Korolev, in order to lift the payload weight of 95 tons he needed a very large rocket. This new rocket would be called the N1, be as big as the American Saturn 5 and would require large powerful engines, similar to the F1 rockets in the Saturn.
Valentin Glushko was the leading Soviet rocket designer and head of the OKB 456 bureau, which had a near monopoly when its came rocket design & production. He specialised in making engines that used hypergolic propellants.
These consist of a fuel and an oxidizer, that when mixed together spontaneously ignite when they come into contact with each other. Korolev thought these were too dangerous for manned missions due to the highly toxic and corrosive nature of the chemicals that made up the fuel.
Glushko said that it was not possible to create a new large engine design that used cryogenic fuel of liquid oxygen and Kerosene and get it ready in time with limited resources and cash. He also sited that at the time the Americans had been working on cryogenic Saturn engines for 5 years and still hadn’t got them to work reliably…….
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