Aside from the number of engines on the first stage and the staged-combustion design of the engines, another important similarity with the N1 was the fact that they never conducted a full-duration static test firing of the first stage. The Soviets lacked the budget to build a test stand that would have allowed a full-scale test, which meant that they had only individual engine tests to go on before attempting all-up flights. This means they had no way to discover problems such as fires in the engine bay, plumbing and electrical control problems, and potential fratricide among the clustered engines before committing to flight. NASA, with essentially unlimited funds, performed full duration test firings of all of the Saturn V first stages before shipping them to the Cape and, in addition, had a structural test rig (in fact, two of them) which could subject stages to simulated flight loadings with hydraulic rams to verify structural soundness.
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