How Do Rockets NOT Work? | The N1

Video from the channel Classic Aerospace History about N1, linked on its Above Ten Thousand entry. Duration: 10:42. Language: English. Video type: Documentary.

An English-language educational video from the channel Classic Aerospace History explaining why the N1, the Soviet lunar launch vehicle contemporary with the Saturn V, failed. It describes its stages and reviews each of its four launches one by one.

The N1 was designed by Sergei Korolev, and the lunar program suffered greatly after his death in 1966. None of the four launches reached space, and the program was suspended in 1974. The second failure, on the launch pad itself, occurred shortly before the liftoff of Apollo 11.

The first stage, Block A, mounted 30 NK-15 engines in two rings. The second, Block B, carried eight NK-15V engines with nozzles widened for high altitude, and the third, Block V, four NK-21 engines. On February 21, 1969, a voltage surge shut down engine 12 and, for symmetry, engine 24; pogo oscillation caused leaks and fire, and the first stage shut down at 68 seconds. On July 3, 1969, the explosion of engine 8 brought the rocket down onto the launch pad. On June 26, 1971, uncontrollable roll ended up breaking the vehicle apart. On November 23, 1972, the programmed shutdown of the six central engines caused a water-hammer effect in the ducts, a fire, and the explosion of engine 4; the escape system saved the simulated payload. As an underlying cause, the video points out that the NK-15 valves could not be reopened once closed, so the set of 30 engines was never tested in a static firing before flight.