Continuity mistake: During the Japanese bombing of Midway, you can clearly see, briefly, battleship masts in the background. Recycled footage from TORA, TORA, TORA.
Visible crew/equipment: On the first torpedo attack on the Japanese carriers, US pilot George Gay is shot down. He exits the plane and swims towards a square floating object. Either he takes size 28 shoes or the actor was wearing fairly short black swim fins. They show twice very briefly above the water. Hard to see, but nobody has feet that long.
Character mistake: When the Strawberry 5 radio operator says he sees the enemy carriers he says "they're behind us" but he's looking to his left side almost as if the carriers are in front of him while the navigator in the cockpit is looking in the opposite direction.
Revealing mistake: Probably another instance of the recycled footage issue with this film. When the Japanese planes begin their attack on Midway Island a wide shot shows many of the Japanese planes with torpedoes attached to them. Shouldn't they all have bombs instead of torpedoes?
Factual error: When the final attack by Japanese fighters on the last U.S. carrier is happening, a Japanese National flag is flying on screen.