The Final Countdown is a 1980 science fiction film that follows the crew of the aircraft carrier USS Nimitz as they find themselves mysteriously transported back to December 6, 1941, the day before the Japanese attack on Pearl Harbor, and are faced with the question of whether or not to alter history. The cast included Kirk Douglas, Martin Sheen, and James Farentino. Made with the cooperation of the United States Navy, the film is notable for being one of the first to feature actual F-14A Tomcats as well as filming carrier operations aboard the actual USS Nimitz: forty-eight of her then-serving crew are credited as extras, some with speaking roles. Filming on the Nimitz was forced to wrap early due to the carrier being recalled for the ill-fated Operation Eagle Claw: pickup shots were filmed on several other vessels. The final shot of the carrier returning to Pearl Harbor is actually the USS Kitty Hawk: this is because in real life the USS Nimitz was stationed in the Atlantic until 1987.
The following weapons were used in the film The Final Countdown:
US Marine guards can be seen carrying M1911A1 pistols as their sidearms throughout the film. During the hostage situation aboard the USS Nimitz, a captured Japanese Zero pilot (Soon-Tek Oh) commandeers an M1911A1 in the Nimitz sickbay. Another Marine responding to the crisis is also wielding an M1911A1, but doesn't fire it during the incident. It should also be noted that the M1911A1s have a gloss blued finish like a civilian pistol, instead of the military parkerized finish.
M8 Flare Pistol
While being dropped off by an SH-3H Sea King on a remote island near Hawaii, Senator Samuel Chapman (Charles Durning) takes an M8 Flare Pistol from the helicopter's emergency gear and threatens to fire it if he isn't taken to Pearl Harbor.
Rifles
M16A1 Rifle
The M16A1 assault rifle can be seen wielded by Marines several times during the film; first when the Nimitz goes to General Quarters following the time shift, then when guarding the Zero pilot. The pilot then gets hold of one of these weapons in the Nimitz's sickbay.
MGC M16 Replica
In the sequences that did not require live firing, all M16A1s are replaced with MGC M16 replica rifles.
Machine Guns
Fake Type 99 Cannon
A pair of American-made North American T-6 Texan trainers (specifically, Navy SNJ variants) owned and operated by the Commemorative Air Force and mocked up to look like Japanese A6M "Zero" fighters (also done in Tora! Tora! Tora!, footage from which actually appears in this film, and they also played P-47s in A Bridge Too Far) are seen attacking a civilian yacht, and later engaged by two F-14 Tomcats from the Nimitz. This is historically inaccurate: no Japanese aircraft took off before the main strike force.
In flying sequences the SNJs alternate between having prop gun barrels mounted in their wings (usually when they are flying directly towards the camera) and no guns at all, while closeups show them firing prop Type 99 cannons, which are actually acetylene-firing mockups. This was a necessity for shots depicting gunfire prior to the advent of CGI since FAA regulations make it virtually impossible to fly a civilian-registered aircraft in US airspace with functioning weapons on board.
M61 Vulcan
The M61 Vulcan appears as the secondary weapon of US Navy F-14A Tomcats and A-7E Corsairs in the film, one of them being used by a Tomcat to down one of the Japanese Zeroes during the dogfight scene. Unlike the Zeroes in the film, the Tomcats were completely genuine, including their weaponry: the aircraft in the film are from two squadrons of Carrier Air Wing Eight (CVW-8). Most shots are of aircraft from the VF-84 "Jolly Rogers" fighter squadron (disestablished in 1995) with their distinctive black tails with skull-and-crossbones markings, though some from VF-41 "Black Aces" (now VFA-41) also appear.
That said however, the effects of the Vulcan on the Zero are unrealistically minor, causing a trail of smoke from the disabled plane which plunges into the ocean largely intact (save for turning into a model shortly before impact). In reality the 20mm shells fired by the M61 would have shredded the notoriously fragile Zero.
While one might expect to see Phalanx CIWS listed here, at the time the Nimitz did not yet mount any: her installations were added during her 1983-84 Complex Overhaul. At the time her main defensive armament was three Mk 25 BPDMS (Basic Point Defense Missile System) 8-tube RIM-7 Sea Sparrow missile launchers, which were replaced with two Mk 29 launchers during the same refit.