Deliberate "mistake": The torpedo hitting the water dropped by the Russian Bear Foxtrot, and the one dropped by the Americans are the same piece of footage.

Revealing: In the scene where Ryan is chasing the undercover KGB agent through the missile compartment one of the valves on the missile tubes is very wobbly as it is bumped. Although given the state of the Soviet Submarine Force maybe this is accurate....

Continuity: When Jack Ryan is being flown, via chopper, to meet up with the USS Dallas, the pilot expresses concern for the fuel situation. First we see this pilot in the right-side seat from a good distance behind his left side as he is talking. When he looks back at Ryan in close-up, the shot is backwards so that he seems to now be in the left seat, looking over his right shoulder (notice his name on the helmet is backwards). Then, after the sub is spotted, he speaks again, and is seen back on the right side, looking over his left shoulder at the left-side co-pilot.

Revealing: None of the exterior storm scenes where rain is present have any visible impact on the actors. No water or mist on face, binoculars, hat brims, etc. The special effect that creates the rain does not correlate to the either actor appearance or background reality - sun reflections, clouds, etc.

Continuity: At the beginning of the film Jack says goodnight to his daughter and then leaves for the airport to catch the flight to Washington. He arrives at Heathrow in the dark. A flight to Washington From Heathrow takes 6-7 hours, and Washington is 5 hours BEHIND London. If Jack leaves at, lets say, 10PM London time, he would arrive at midnight US time. But in the film he's met upon arrival and gets straight into a car at the airport and drives to the CIA offices for his meeting with Greer. The problem is it's daylight when we see the car driving to Langley which is a relatively short drive from Washington and the Airport(s) - where did the night go?

Factual error: In both the opening in Alec Baldwin's house and on the sub at Scott Glen's station, you can see an edition of Jane's date 1977-1978. Since this takes place in 1984, is this really the most recent edition of this important reference/information text? The sub commander might have an old favorite, but also a CIA employee would be referencing a 7 year old text?

Factual error: Regardless of the factual error about the visible distance in Atlantic waters, just before the Red October and the Dallas communicate via Morse code, there is a scene where both submarines are diving upwards. The two submarines are hardly more than 50 yards apart even though, only a few seconds earlier, a crew member said that they were about 300 yards apart.

Other: Towards the end, after the cook shoots at Sean Connery and Sam Neill blocks it, they open his jacket to look at the wound. His jacket is perfectly intact and his shirt only has a red stain - there is no visible hole.

Continuity: When Jack is getting off the plane in the beginning of the movie, his jacket collar is up. When he meets the 2 men who are there to pick him up, the collar is now down.

Continuity: At the end of the movie in the scenes with Connery and Baldwin on the tower of the sub, the light of the moon is obviously shining on their faces but the reflection of the moon stretches out across the water behind them.