Visible crew/equipment: In all the President Kennedy White House shots, you can see the boom mic peak down several times. Look for the group shots, and the boom mic will be there.
Continuity mistake: The Pierce fires its guns to clear the barrels of the already loaded starshell. This is technically correct but when the starshells burst there are four of them i.e. the same as the number of gun barrels on the Pierce. Earlier however, when the Pierce first confronts the Grozny, there is a shot in the 5in gun turret showing at least one barrel being loaded with practice shell (i.e. solid shot). The Captain reports to the Admiral that the guns are loaded.
Continuity mistake: On the Pentagon the plot shows the USS John R Pierce intercepting the two Soviet ship but the marker on the plot says DD722 (it is upside down). DD722 was the USS Barton whilst the Pierce is correctly shown in the external shots as DD753.
Continuity mistake: O'Donnell's son's report card has a grade D for effort. However, according to the scale printed directly below the grade, the awardable effort grades are A, B, C or U - not D.
Continuity mistake: Just as the American pilots are getting ready to take off from their base on the recon mission you can see in the background a yellow tanker truck..it's a mid 80's International S1800 series not a 60's Loadstar.
Continuity mistake: At least two close-ups of television sets show the vertical colour stripes of a Trinitron tube (combined with the scan lines it resembles a crosshatch). Sony didn't introduce the Trinitron until 1968. Sets before that used a "triad" of phosphor dots.
Continuity mistake: When the people are listening and watching the president, the view has a bunch sitting around with Pepsi products and there is a bottle of Pepsi that says "One Pint" on it. I'm pretty sure that Pepsi did not have this bottle in 1962.
Factual error: One of the scenes shows the buildup of American readiness as tensions mount. A B-52 bomber appears carrying four white menacing-looking missiles under her wings. Such missiles can easily be identified as the Hound Dog type, which was under test in the mid-60s but never became operational. America would never deploy those missiles either for real or for training, because the project was scrapped before even being accepted into the Air Force.
Continuity mistake: There is mention of an Atlas missile launch while we are being shown the lift-off of a Titan missile on the screen.
Continuity mistake: The crew on the destroyer imposing the blockade initially saw the two Russian freighters on their radar screen, and then they saw a third 'blip' on the radar screen as the ships approached the blockade. The radarman identified the first two blips as surface ships, and the third blip as a submarine. Unless that was a sonar display, they would never have seen the submarine. The third contact would have been made by the ship's sonarman, and the two surface contacts would have been identified by the radarman.
Continuity mistake: When O'Donnell drives Robert Kennedy to meet with the Russian Ambassador to avert WW III, the exterior of the car changes from rain-soaked to bone dry several times during the drive.
Factual error: When Kennedy is being shown how far the Soviet MRBMs could reach from Cuba, the South American country of Colombia is spelled "Columbia."
Factual error: In the last scene in the film, Costner and his family are seen having breakfast before going to mass. The problem is, they are portrayed as a strict Roman Catholic family. No strict Roman Catholic family would eat breakfast before going to mass at that time. In 1963 you were not even allowed a glass of water from the moment you woke up till you took communion at mass.
Factual error: The U-2 was built to fly on the edges of its flight envelope: too slow yet too high. The pilot had a very difficult time keeping it level and straight so it wouldn't stall. In the film, a U-2 evades missiles by jinking up and down as if it were a fighter, until a final missile strikes it down. That aircraft would never have been able to even climb away from the first missile, all it could do was sit and wait for hell to reach up. Those aerobatics were completely out of the question for a U-2.
Continuity mistake: When the U2 gets shot down, the missiles launched appear to be truck launched SA3s. The only missiles that the Soviets possessed at the time that could get anywhere near the altitude of a U2 are SA2s, which are taller than telephone poles.
Continuity mistake: In the final interception of a Russian ship, the vessel is described as a tanker, but in reality, the ship shown on the screen is a freighter.
Visible crew/equipment: In the beginning of the film when the family is gathered around the table for a meal, the crew, cameras, and lights are visible in the reflections of the window.
Factual error: On the scene where the 2 low-flying RF-8 Crusaders are being shot at, the Cubans and Russians are aiming what supposed to be a mobile SAM launcher, that resembles SA-3. As far as I know, at the time the Soviets had no mobile SAM, until the introduction of the SA-6 in 1966.
Visible crew/equipment: At 54:20 they show the commander of the ship looking through binoculars they then show a shot of the two ships taken from what was supposed to be the American military ship. On the far left of the screen is the American ship visible is somebody in a blue life jacket just like the military personnel however there is someone else who is sitting down with long hair and a beard (most likely a crew member), that is obviously not in the military.
Continuity mistake: There were several flash frames in the film - the most obvious was when an eight appeared in an atomic bomb shot. The eight was from film leader and the result of a bad edit.