I wonder what analysis was done by the professor. The N1 failures were attributed to the engines, NK-15, which had too aggressive parameters for the time. The

I wonder what analysis was done by the professor. The N1 failures were attributed to the engines, NK-15, which had too aggressive parameters for the time. The next generation of engines, NK-33, showed much greater reliability. With the system of such complexity, which was planned to get to work with test launches - because ground-based test systems didn't exist (for the first stage) - it's no big wonder first four launches weren't successful. Even with them the 4th almost completed the 1st stage burn. The chances for the next flight, with NK-33, to be successful at least for the first stage were rather good, and in few more flights they could get to operational reliability. Time and money were against the engineers, however. This all doesn't prove ~30 engine stages can't fly. They are more complex - sure, but still.