Factual error: On board Air Force One, Helmsley is informed that the Continental Displacement has moved everything 23 degrees to the South West. In this case, China would have moved over 1000 miles in that direction, giving Jackson, et al. further to fly, rather than closing the distance.
Factual error: American officials, including the president himself, continually refer to the other G8 leaders as "heads of state." They are, in fact, heads of government. The United States is the only G8 country which combines the head of state and head of government into a single position. The others have a separate prime minister (or chancellor in Germany) and president (or sovereign in the UK, Canada and Japan). No American official is likely to make this mistake in reality. The head of government of Italy is appointed as "Prime Minister" also in the Italian version; actually the correct wording should be "President of the Council of Ministers"
Continuity mistake: Nima says that Tenzin will meet them at the West Gate of Cho Ming valley, but a sign at the gate says it is the East Gate.
Other mistake: When the monk arrives with Jackson and the others at the gate leading into the secret entrance of the ships, the countdown to impact timer reads about 28 minutes. It is highly implausible that the group, which contains elderly and small children, are able to get to the top of what looks to be a 100 story staircase in less than 15 minutes without breaking a sweat. Once they are inside the hatch, the countdown to impact timer reads about 13 minutes.
Continuity mistake: When Jackson and the kids are at the dried up lake in Yellowstone park, they walk past the carcass of an elk. We change to the long shot, and when the army arrives, the carcass has gone. (00:21:35 - 00:22:05)
Factual error: Schwarzenegger's term expires on Jan. 2011. This would be the end of his second term and the state constitution prevents him from serving a third. And yet he is apparently still governor in 2012.
Plot hole: After leaving the Santa Monica Airport the pilot decides for no apparent reason to fly into Downtown and fly between the buildings. Anyone from LA would know that in order to actually fly into downtown from the airport one would have to actually aim for it. It's not like you take off from the airport and then you are stuck having to fly in amongst tall skyscrapers.
Factual error: In the Yellowstone sequence, Jackson drives the RV looking for Charlie. They drive past a sign saying "Mount Big Horn". There is no Mount Big Horn in Yellowstone. There is, however, a Big Horn Peak outside the park to the north east.
Factual error: Little over an hour into the movie, Yellowstone blows up into a huge volcano. The pyroclastic flow that follows the camper is going at such a speed (the speed of the flow can be seen when the plane is in the air) that it would have overtaken the camper well before it has reached the plane. Even if the cloud would have been slowed down by hills, it would have, after the camper reached the plane, overtaken the plane long before it could take off.
Factual error: The coat of arms behind the German chancellor in the briefing scene is wrong. First of all the actual German coat of arms is not oval and secondly this is not the coat of arms used by the German chancellor. The one used by the German chancellor is hexagonal and could also be found on the old German currency.
Continuity mistake: When Jackson comes to pick his kids up to go camping, he is shown passing by the back side of his limo and the trunk is fully opened, but in the next shot the trunk is still opening. (00:14:20)
Continuity mistake: When the RV camper van lands after its jump on the runway, you can see the steering gear and passenger front wheel has collapsed. In the next shot when Jackson enters the camper to retrieve the map, you can see the wheel is fine, and then its damaged again in the next long shot.
Continuity mistake: While Carl is reading the note, a waitress passes behind Adrian. Half a second later she's 3 meters behind repeating the movement.
Revealing mistake: A wire is visible when the car flips over in Paris. The shadow is easier to see.
Factual error: Right when the plane takes off from the airport in Las Vegas, the plane barely misses the Wynn Venetian and hits the Eiffel tower at the Paris. This is impossible as the airport is at the far south end of Las Vegas Blvd. and these hotels are at the far north. They would have had to fly over four miles of other casinos before ever reaching them.
Continuity mistake: When Jackson picks up his kids to go camping, we see nothing on the sidewalk grass field in front of their house. But when he returns home to drop the kids off, we now see that there is actually a pedestal displaying the address of the house, we can also see this pedestal when the earthquake hits.
Factual error: In the film, the world is falling apart because the earth's neutrino particles have mutated and are heating up the earth's core intensely. The top surface of the world would have been utterly destroyed under the pressure of such power before the core could have come close to beginning to boil.
Continuity mistake: Right before the scene where the earthquake happens at the supermarket, we see the crack moving through the parking lot. The cars are parked parallel to the store. We see car after car shake, etc, until it gets close to the front door of the store. After the earthquake, when the news is on the TV, it shows the store after the crack has gone all the way through. The parking spaces and cars are facing a completely different direction.
Factual error: Several scenes in the movie show the tidal waves and tsunamis sweeping people and objects away, which is utter fantasy. The air pressure wave that is in front of the tidal waves and tsunamis would blow people and objects away long before the water did.
Chosen answer: Its a safety device so the ship doesn't put to sea and ends up flooding the ship. The passenger ferry Herald of Free Enterprise capsized in the port of Zebrugge in 1987, precisely because the doors were not shut properly.
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