Character mistake: As the helicopter crewman sees the Dallas surfacing, he says something along the lines of, "Sub at three o'clock". The next shot is from inside the helicopter and shows the sub and a part of the starboard landing gear retracting pod. This shot puts the Dallas closer to one o'clock. (01:24:00)Christoph Galuschka
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)
Trivia: Paramount Studios essentially rented a US submarine to be in the movie. The USS Houston (SSN 713) played the USS Dallas and the surface scenes were filmed off of Long Beach, CA and Port Angelas, WA. Two crewmembers off the Houston were actually given very small speaking parts in the movie.