Factual error: Several times during the movie, we can see the radio operator with the screen contents "printed" on his face. As everyone knows, that just doesn't happen in real life. (00:25:00)
Continuity mistake: As the Alabama dives for the first time you will notice that the periscope and antennae masts protruding from her conning tower keep switching from up to down, indicating that the film crew used footage from two different sub dives to achieve that sequence. (00:18:50)
Answer: In a war situation, the Captain is absolutely NOT allowed to try and contact anyone, lest it gives their position away, which is why he was unable to question or confirm the order.
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