Factual error: Doug Masters and his friend Reggie would be grounded on the spot and have their pilot's licences suspended (and in all likelihood cancelled) after buzzing the motorcyclist. Their flying is grossly unsafe. They would be visible for miles flying well below a safe altitude, but even if they were not seen their radio traffic and radar tracking would tell the authorities everything they needed to know.
Factual error: Tom Cruise says of the song 'Sitting on the Dock of the Bay' "my folks loved it". However, his father died in 1965, his mother died "shortly after him", and the song wasn't written until 1967.
Factual error: The mounted machine gun fires far too many shots for the limited supply of ammo it has in the box attached to it.
Factual error: When the Delta Force lands on a beach, prior to their assault, their landing craft is lit up like a christmas tree. The commandos wear dark uniforms and have blackened their faces, but they also carry bright white ropes around their chests. Some of them are scuba-divers, wearing yellow oxygen-tanks. In short, in the real world they would have been spotted within minutes.
Factual error: Calendar date at the very beginning of the film (in the police station), shows the dates of Saturday 20th/Sunday 21st July 1983. However the 20th and 21st July 1983 fell on Wednesday and Thursday.
Factual error: Bunny bites an aluminum beer can in half. Beer cans weren't aluminum until the mid 70s. He would have hurt his mouth on that one.
Factual error: When we first see Kurgan in modern day New York, he begins to assemble his sword in a motel room. The very fact that he is assembling his sword the way he is, snapping segments together, especially the blade itself, which is segmented in the middle, would make that quite possibly one of the weakest and most inefficient weapons a person could ever wield. Being that it is segmented the way it is, it is structurally weak, and a clash against another sword, or any hard surface for that matter, would break the segments apart easily.
Factual error: During the karate tournament towards the end of the movie if you'll notice the American flags in the background you'll see that they are displayed improperly. Whether flags are being displayed horizontally or vertically, the stars should always be on the left side of the flag.
Factual error: Towards the last scene, Howell and Hauer share the same shotgun (Ryder to take pop shots at Jim in the jeep, Jim to ultimately fire three shots to kill Ryder). The shotgun used can hold at most seven or eight shells, not the 12 or more that are fired between Ryder and Jim starting from when Ryder escaped the bus.
Factual error: After Miyagi and the kid have the conversation with the military man they drive off and round a corner. A scene is shown of the sea and very visible is a shot of "Chinaman's Hat" Island. A feature that if you have ever been to Oahu, Hawaii near Kualoa Point you would know is on the island of Oahu and not in Okinawa where the movie is supposed to take place. See Chinaman's hat at this site: http://www.hawaiiweb.com/oahu/sites_to_see/chinamans_hat.htm.
Factual error: When Mitchell is working on his Jaguar, he walks from the bench to the car, places a spark plug, then tightens it with a ratchet wrench. The audio proves, however, that the wrench is set to loosen the plug, not tighten it. (01:11:50)
Factual error: The marines' rifles are supposed to fire "standard armor-piercing rounds", which should have done way more damage than producing a few sparks on the frail sheet metal table in the med bay when Hudson shot the face-hugger threatening Newt. "Standard AP rounds" would have pulverized the table and created a huge hole in the wall behind it.
Factual error: In the scene where Tommy Lee Jones's character shoots down the helicopter. The helicopter has a Canadian aircraft serial number - C-GLCD. Since it's being used by the New York Police Department in New York's Central Park we should expect it to display an American registered serial. (00:53:30 - 00:54:30)
Factual error: After escaping from the back of a NYPD cruiser that apprehended her at the British Consulate, Terry runs into the NYC 57th Street N/R line subway station. In the very next shot, she is running past Cole's French Dip Restaurant on 6th Street.in Los Angeles. The restaurant sign even mentions its location.
Factual error: Spence says that Claudia is Italian, but the very efficient butler greets her with "Buenos dias", and according to Ellen she was a big Chilean film star. Nothing strange that Ted Danson would be wrong about her nationality like he often is wrong about names, but in the end credits we have a similar Spanish/Italian language mixup with an "Italian director" listed, when the person in the movie finale speaks Spanish. (01:25:00)
Factual error: Murphy shouldn't even be in charge of escorting Arabella to the bathroom and booking her. Female police officers are put in charge of female prisoners.
Factual error: Tuba pranks the store manager while he is reading adult magazines. One of them though (the one he is holding) is the August 1985 issue with Angela Nicholas on the cover. The previous scene took place at the Hong Kong Marathon of 1985, in January.