Plot hole: Bomb squad vehicles are present at the airport when the plane lands. There is no bomb disposal unit in Goose. If one is needed it has to come from two provinces away - travel time by vehicle, in March, going flat out: minimum 20 hours + a 2.5 hr ferry trip. Not to mention that the markings on said vehicles are American: transportation of those vehicles from the US wouldn't have been any easier than from Canada, on the contrary, so again, they wouldn't have had the time to bring them over.
Other mistake: When either Kyle or Carson run down the staircase the rails move significantly. On a real plane this would not have passed the pre-flight safety checks and the plane would have been grounded. Nothing in the film suggests the rails would have loosened.
Factual error: The Royal Canadian Mounted Police are shown checking baggage in the final scenes at the same time that FBI agents are making arrests. The flight landed in Goose Bay, Newfoundland and Labrador, Canada. According to the Criminal Code of Canada, any crime committed during an international flight that ends on Canadian soil is deemed to have been committed in Canada. That being the case, the RCMP as the national police force has full jurisdiction. There is no way the FBI would be involved at that point.
Plot hole: Carson states to the captain that Kyle is a "hijacker" and is threatening to blow up the plane unless they transfer $50 million to an account (which we don't see.) He also tells the captain that she refuses to negotiate, and to agree to the ransom without speaking to her. This takes us far more than suspension of belief that the captain would not question about the detonator or other specifics. Therefore, it is very unrealistic that Carson could have predicted the captain would have agreed to the ransom simply because he thinks the captain would immediately trust an Air Marshall's word, not to mention that Carson shows no evidence of Kyle being a "hijacker" when that could be helpful in his plan whatsoever. He also never counts on the fact if the captain actually didn't move the money to the account when he said he did over the phone.
Continuity mistake: In the shot when Carson put the bomb in Avionics to activate it, he puts down two parts. The part to the right (from Julia's perspective) is a little inclined. But when Kyle is in Avionics looking for Julia, that part of the bomb is not inclined.
Continuity mistake: When Stephanie is about to check avionics, Fiona holds the flashlight by the lamp end (bulb) as Stephanie takes the flashlight. However, in the next shot, Fiona still holds the flashlight, but she now holds the other end as Stephanie takes the flashlight from her.
Other mistake: Carson's face would have been a whole lot more disfigured had he actually been hit that hard with a fire extinguisher.
Continuity mistake: Near the end when the Air Marshall is getting off the plane to "get the two agents" there is a shot of him from behind walking off the plane with snow covering most of the ground, but when the shot cuts to a wide shot from the side of him all the snow is gone.
Revealing mistake: When Kyle is running up to the cockpit to pound on the door for the captain, you can hear an extra shout out "Hey, Jodie Foster."