Days of Future Past: Part 2 - S1-E12
Factual error: When Gambit is inside his mini-jet after escaping from Bishop and Wolverine, his radar screen says "Washington D.C." but the graphic above it is Washington state.
Slave Island - S1-E7
Factual error: When Professor X is calling Moira McTaggart in Scotland, the phone number he uses is shown to have only dialed the exit code of 011, followed by a fictional seven-digit number with a 555 prefix. Since he is calling from the United States, he would have to dial the country code (44) and area code for the right part of Scotland. Plus UK numbers at that time had at least 9 numbers. (00:08:20)
Factual error: After Wolverine falls into the ocean, he surfaces and grabs onto a platform of ice just after Sabretooth gloats about defeating him. Since Wolverine's skeleton is coated with a heavy metal, he wouldn't be able to surface. He would sink to the bottom and at the least have to resort walking to the nearby cliff wall and using his claws to scale it until he is back on the ground. (00:03:48 - 00:04:24)
Days of Future Past: Part 2 - S1-E12
Factual error: The U.S. flag has 13 stripes. When Bishop is telling the X-Men how Gambit's betrayal will affect the future, the flag shown flying outside the Capitol building is missing two stripes. In the next shot showing the flag draped over the coffin, it has at least 17 stripes. (00:04:25)
Factual error: When Senator Kelly is giving his campaign speech, the U.S. flag behind him is missing one stripe and has at least two too many stars. (00:19:30)
Factual error: When a parachuting Xavier is about to land, you can see his legs are bent at the knee to brace for landing. Since Xavier is a paraplegic, he shouldn't be able to do this. (00:19:14)
Night of the Sentinels: Part 2 - S1-E2
Factual error: When the President is giving an address, the Great Seal behind her incorrectly depicts the eagle with its head turned towards its left wing. It should be turned towards its right wing. (00:13:19)
Factual error: The commercial airplane that Rogue is piggy-backing to Muir Island has no overhead storage bins. Just a shelf running the length of the cabin with luggage stacked on top, which is not something that the FAA or any other national aviation authority would permit. (00:09:20)
Factual error: When Rogue is flying the dome up to the top of the mansion, she is flying at a diagonal angle and using a rope to tow the dome behind her. On its way up from the ground, the dome is also at a diagonal angle, when its mass along with the force of gravity and the slow speed at which Rogue is moving dictate that the dome should swing like a pendulum. (00:06:10)
Factual error: When Xavier is getting ready to get back into his hoverchair, you can see him raise himself to his knees, even though he is a paraplegic. (00:13:43)
Night of the Sentinels: Part 1 - S1-E1
Factual error: When the Sentinel reaches out to try to grab the dog, it smashes its hand against the grass and produces numerous cracks in the lawn with a metal clanging sound. Neither of these things would happen. The grass would have a bunch of divots in it, and the sound would be similar to something heavy falling in dirt. (00:02:09)
Answer: Chris Potter, the original Gambit voice actor, did indeed quit the role in the 4th season. His last episode was The Phalanx Covenant Part 1 so it seems reasonable that Fox would limit the use of the character even though it was recast. It doesn't appear that Potter left the role due to animosity, he stated in an interview that he wished to play Gambit in the first live action X-Men film.
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