Trivia: The movie Firefox is a Soviet built radar-invisible aircraft. In reality, the American F-117 Nighthawk stealth fighter was made possible by the work of a Russian physicist, Dr. Pyotr Ufimtsev. (Soviet designers thought his theories worthless!).
Trivia: Through sheer coincidence, the designers of the "Firefox" used flat plates and odd angles on the model. This is the same design technique that makes the actual stealth fighter invisible.
Trivia: To film the scale models of "Firefox" they had to come up with an entirely new method of doing the matt filming, as the model has a reflective skin, unlike the normally-required matt paint finish so the model doesn't reflect the blue screen, which would create "holes" showing the background apparently on top of the image of the model. It was called "Reverse Bluescreen", and involved filming a phosphorescent painted model and photographing it first with strong lighting against a black background, and then with ultraviolet light to create the necessary male and female mattes to separate the foreground model and the background footage. This enabled the shiny black model to be photographed flying against a clear blue sky and gleaming white snow and show reflections.
Trivia: The footage of the submarine 'Mother One' breaking through the ice was borrowed from the movie Ice Station Zebra (1968); both subs are numbered 509.
Chosen answer: There was just an explosion in the hangar and in the resulting confusion none of them were sure why it was moving. To get it away from the fire is not unreasonable. Also, the Soviet military is not big on showing initiative. Unless told to disable it, none of the guards would risk severe punishment for damaging a valuable aircraft.
Grumpy Scot