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Factual error: When they are at Aunt Meg's the first time, they get word that a tornado has been spotted and somehow they already know its rating. Tornadoes get their ratings from the amount of damage they do. This is determined after the tornado is gone.
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Factual error: The actual Tsavo lions responsible for the killings had no manes - see for yourself; they are on display at the Field Museum in Chicago. [The filmmakers employed artistic license in using maned lions. They were also certain to include - at the very end of the movie - footage of the real Tsavo man eaters, as they appear in the Field Museum.]
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Factual error: The portrayal of the firing MLRS before Denzel's unit moves off is ludicrously inadequate. The rockets launched from the MLRS resemble a space shuttle lift-off, but in the movie it was more like a sparkler thrown into the air.
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Factual error: Even aside from the ridiculous recoil that a railgun would cause (yeah, I know they don't use gunpowder, but there's got to be SOME opposite movement, surely), how come when the darts (bullets, whatever) go straight through people, they still get thrown backwards? The passage straight through them means minimal energy being transferred to them, and as such they shouldn't be hurled backwards that much.
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Factual error: After Hardy dies and they're going through his possessions, a football scarf is pulled from his kit bag. The scarf has a Sunderland AFC badge. The film is set in World War II. The badge on the scarf was introduced in the 1970s.
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Factual error: When The Oneders are recording their song with Uncle Bob, there is an In-N-Out cup sitting by the recording equipment. There are no In-N-Out restaurants in PA.
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Factual error: When the boys have a night on the town with a bunch of eager Dutch girls, the girls somehow forget their native tongue and start to chatter in Danish.
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Factual error: We learn that the previous sheriff, Charlie Wade, took revenge on anyone who smuggled illegal immigrants across the border in the late 1950s - we are shown the smuggling, as Eladio Cruz hides a group of Mexican men in a watermelon truck to take them across the border. However, in the 1950s, the border was not fortified the way it is now - the smuggling shown would simply not have been necessary.
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Factual error: Several times during the highway scenes if you look closely you can see that some of the cars and trucks are early 90s models even though it's supposed to be 1986 or 1987.
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Factual error: The Lee Enfield rifle is chambered by singular repetitions with a bolt action. When Collins' wayward friend is shot in the water, the rifle shots are rapid semi-automatic fire.
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Factual error: Towards the end of the song "Out There" Quasimodo climbs onto the large spire on the roof. That spire was added in the 19th century and thus didn't exist when the movie was set.
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Factual error: During the riots and the start of the film a model of armoured car and grenade launcher are seen, which were not manufactured until the 1970's.
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Factual error: When young David and his father show up at Ben Rosen's house, there is a Jewish mezuzah (a handwritten tiny scroll of parchment with a passage from the Bible enclosed in a case) affixed to the doorpost. The position of the mezuzah is incorrect. It should be higher up on the door jamb and the top should be angled towards the house, not the other way round. (00:15:00)
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Factual error: In a radio news voice-over shortly before the first chase scene, the newsreader comments that "Calls have flooded in from all over the world regarding Dr Barkley's research." He then goes on to mention that the Royal Academy in England has expressed an interest. The "Royal Academy" is more formally the Royal Academy of Arts. They probably mean the Royal Society, which is the most important scientific institution in the UK.
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Factual error: In the infamous Highland bus scene, the driver can be seen issuing tickets from a computerised ticketing machine - astonishing really - the film is set in the early 70s.
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Factual error: There is a major error in the scene where Geena Davis steals the tractor trailer. They show a closeup of the brake line between the truck and the trailer being cut. The problem arises when fluid starts pumping out of the line and Geena screams because she's lost the brakes. First, every tractor trailer is equipped with air brakes, so there is no fluid in the lines to leak. Second, if these air lines are severed it causes the brakes on the trailer to lock up and drag the truck to a stop.
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Factual error: When Mel Gibson is leaving NYC by car they come out of the Lincoln Tunnel onto route 4, that is impossible. The only way out of the Lincoln Tunnel is onto route 3. Then when they are driving through New Jersey on route 4, Mel Gibson says "There is the exit for 208." While you can get to 208 from route 4, they were driving on route 4 east, heading back towards NYC, not route 4 west which is the way onto route 208 they showed in the movie.
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Factual error: In one scene, the pitcher has an Atlanta Braves uniform on and the catcher has a Colorado Rockies uniform on. Unless this was an all star game, how could this be?
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Factual error: Although many thing have been changed to reflect the early-mid 80's when the film is set, it is often possible to see 90's cars in several scenes.
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Factual error: Throughout the entire Varsity/JV game, the Varsity team makes at least 20 penalties that aren't called. They also refer to a tripping call as hooking, even though the Varsity player obviously goes for the JV players ankles.
Suggested correction: The scale back then was based on the size of the tornado, it's only more recently it is based on damage. So during the time of the movie, the scale was being used correctly for size not damage.
The Fujita scale was introduced in 1971 and was in use during the 90's when this film came out. The Fujita scale measured the damage caused by a tornado to man-made structures after ground or aerial surveys, it was not a measurement of tornado size (an F5 tornado is a tornado that's rated on the Fujita scale). It is true the Fujita scale was replaced by the enhanced Fujita scale in 2007, but that was only to align the ratings to the damage better, it did not change rating tornadoes from size to destructive powers.
Bishop73