Character mistake: While the engine room is flooding, Stepanik tries to put a jubilee patch on the pipe by walking towards and deflecting the water. While it looks cool for the movie, it is definitely not the correct way to apply this type of patch.
Character mistake: When Pascal gives his mutiny speech he refers to comsubpac, the Submarine Command for the Pacific fleet. He should have said comsublant. It seems to be a common theme of mistakes seeing as the museum sub they used for the Stingray is kept at a pier in San Francisco. Most of the scenes at dock are filmed there and at sea in nearby waters. Its possible that the original script was based on a west coast 'war game' and later got changed after a number of scenes were already filmed. (01:01:00)