Continuity mistake: When Ms. Lewton dies, she is grabbing her bleeding neck with her left hand. While walking into the kitchen, she leans onto the kitchen table with her right hand. Later in the scene, when Alex comes and tries to help her, we see the bloody left hand impression on the table, even though we should see the right one.
Factual error: The flight attendants didn't do the safety briefing properly. None of the flight attendants show the demonstrations. Also, the safety briefing should be given during taxiing to the runway. But in the movie, the flight attendant had finished the safety briefing before the door of the plane closed. During the safety briefing, the flight attendant said that the aircraft has 6 emergency exits. How come a 747 has only 6 exits? A 747 in fact has 5 main deck exits on each side, which means on the main deck there are 10 exits. Judging by the picture of the plane on the DVD inner cover (New Line Platinum Series), the 747 used in the movie most likely is the 747-200 series, which means the upper deck has one emergency exits. All in makes the plane has 11 exits, almost double the number said by the flight attendant. And during the take off, when Alex looks outside the plane to the wing, he sees that the flaps are just being deployed. When a plane is taking off, the pilot needs to make sure that the flaps are deployed BEFORE they are actually on the runway. (00:10:05 - 00:17:00)
Factual error: When the teacher gets killed, the vodka on the floor catches fire, and there's still enough alcohol left that the fire follows her? I don't think so - vodka will burn, but not that well.
Continuity mistake: In the scene where Billy gets his head sliced off by a piece of metal that fell off the train, as his head rolls away his hair is a much lighter shade of brown than it was during the rest of the film.
Continuity mistake: When Alex is talking to Clear in her garage, one strand of her hair keeps changing, first curled under, and then straight, back and forth...
Continuity mistake: Near the beginning, when they are at the Memorial for the school, look closely to the right of Devon Sawa right after he and the other gal look at one another - an extra with red hair walks in front of him, in the very next shot Devon gets up, and the same extra is now behind him.
Other mistake: When the plane takes off in Alex's vision, the plane begins to go into a nosedive, and the entire left fuselage is blown apart, sucking many people out of the plane. The plane then explodes completely, but in reality, the plane just takes off, and explodes almost instantly afterwards. No struggling with the plane is shown in reality, nor is the plane going into a nosedive. This is also proven in FD5, which is a prequel. The jet engine explodes, leaving a flaming tail, and the plane spinning out of control. The plane just simply "explodes" without any signs of struggle.
Continuity mistake: When you see Alex watching the news report about the crash of 180, after coming back from the airport, you see his mum and dad asleep on the couch with a pillow at the end of his mothers foot and a few shots later after hearing the loud thunder, the pillow is lying on her ankles.
Character mistake: In scenes following the plane crash, authorities refer to the 'National Transportation AND Safety Board.' The organisation is called the 'National Transportation Safety Board' - no "and".
Character mistake: The scene where Clear is trapped in the car and Alex is trying to save her, he incorrectly tells her the tires are grounding the car and to not touch anything. Rubber tires insulate the car preventing the charge from reaching the ground. If Clear were to get out of the car touching metal on the car and the ground at the same time she could be the conduit for the charge to pass through. (01:25:50)
Continuity mistake: After Alex reads his porno and throws the magazine at the owl, that one piece of paper with "Todd" pops out of the fan after the magazine got stuck in it. Now, this is a very small mistake, but if you look at the shape of the piece of paper, the one short stump side changes between takes. Like I said, it's very small differences, but there are differences.
Visible crew/equipment: After Alex walks into Ms. Lewton's home before he discovers her blood on the floor, you can see a crewmembers shadow moving on the light brown TV table. (Note the shadow doesn't match Alex's movements).
Continuity mistake: A reporter takes a photo while Clear and Alex talk at the memorial. When we see the photo in the article, it's at a different angle and Alex has vanished from where he should be next to her.
Continuity mistake: Alex buckles his seatbelt when he first sits down on the plane, before the girls ask him to move, making him have to unbuckle to move for them. When he wakes up after his premonition, he immediately jumps out of the seat, not buckled in.
Plot hole: During the premonition, Carter and Terry are sitting directly next to each other. However, we know that before Carter dies, both Terry and Lewton (who is sitting 2 rows in front of them) have to die first. When Alex sees the report that marks the explosion path, it suggests there is a chain reaction that goes from Tod's seat to Terry's, and then Lewtons. If this is true, should Alex have not died with Tod and Carter with Terry? Tod can actually be seen getting hit in the head with somebodies luggage, and if this is how he died, the news report suggesting a 'chain reaction' is wrong; Tod's seat never explodes. Can anyone tell me if the drawing Alex did with the line going from seat to seat (before the explosion) is not supposed to be an explosion? If you slow down the premonition, both Terry's seat and Lewton's seat blow up about a split-second before the explosion erupts - this is possible but the distance of one of the explosions from Lewton is larger than the explosion from Carter.