Revealing mistake: When the dummy plane is shot out of the sky by the fighter pilot, a piece of the plane shoots off into the top left of the screen and bounces off the sky background. (00:23:05)
Revealing mistake: While the Seaview rocks violently back and forth from the concussion of the under water explosion, the pencils, folders, papers, etc., on the navigation table do not move.
Revealing mistake: The switch that Phones uses to turn off the television set is labelled "BRIGHTNESS".