Tobor the Great (1954)

As projected here, a thinly-disguised NASA, working with nuclear rockets, is ready for manned flights in the mid-fifties...but Dr. Ralph Harrison doesn't think so, and resigns in protest. Colleague Prof. Nordstrom promptly enlists his aid in developing an alternative robot Spaceman! Naturally, foreign spies are keenly interested... Uses documentary footage of early space research.