Factual error: In the opening scene of the movie, the Red October is being escorted out of the Russian harbour by a United States Coast Guard Cutter and U.S. Navy sea tugs. (00:02:30)
Factual error: 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? (00:06:00)
Factual error: When the USS Dallas submerges to attack the Red October, they rig for battle stations as well as rig for red. On a submarine, rig for red is only for periscope depth operations at night, to allow control room watchstanders eyes to adjust to the darkness topside. No other area on the boat rigs for red. Throughout the movie the lights darken along with battle stations. No naval ship would reduce visibility on purpose in a heightened state. (01:31:00)
Factual error: When Jack Ryan is chasing the Cook's Assistant Igor Loginov through the missile compartment, the compartment shown does not exist. Russian Typhoon submarines (of which the Red October is a variant, just with a new propulsion system) have a pair of cylindrical pressure hulls - each containing a missile compartment - on either side of the missile tubes. The location where the fight takes place in the movie would be inside a free-flood area in a real Typhoon. (02:01:20 - 02:05:00)
Factual error: Aboard the aircraft carrier, there is a closed-circuit TV that shows the operations on the flight deck. At one point, a gull-gray F-14 Tomcat, in obvious distress, comes in for a landing. The camera cuts away from the TV to Ryan's face, and the cuts back to the TV. All of a sudden, the plane crashing is no longer an F-14, but an old Korean War-era fighter (F-9F Panther of VF-21), colored the dark blue the Navy stopped using in the 1950s. The director chose to insert a piece of stock footage from George Duncan's crash on the deck of USS Midway (CV-41) on July 23rd, 1951 rather than build a model F-14 to crash for an otherwise unimportant scene.
Factual error: When Ryan is brought on board the Dallas, Captain Mancuso climbs down from the conning tower, through the hatch next to the control room of the sub. He then walks/runs down two flights of stairs and enters a short corridor where Ryan is now dropped on the floor by the safety diver and another crewman. I am unsure of the exact location of the lower hatch of the escape trunk on a 688 sub, but I suspect it would be on mid deck. When the camera turns to face Mancuso again you see the curvature of the hull next to him, suggesting this takes place on an upper floor on the sub. So why did he run down two stairs to seconds later end up on the top floor of a sub with only three floors inside the pressure hull?
Factual error: In some stateroom scenes in the October the bulkheads have numerous little lockers installed because storage space on a submarine is at a premium. The latches on the lockers are of a unique design created only by USA Navy ship and submarine construction shipyards.
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.