Corrected entry: During the scene where the plane flies into the storm, the oxygen masks drop from the ceiling and a voice is heard explaining how to use them. The masks should have dropped long before that, when the prisoner blew a hole in the side of the plane with his gun. The masks would have dropped as soon as the plane began decompressing.
Corrected entry: When the plane decompresses from having a bullet fired through its skin, there are two major problems with this scene. First, there is no conceivable way that the hole could be sealed by placing a briefcase over it, as the stewardess does. Secondly, without an oxygen mask on, everybody on the plane, including the stewardess, would have fallen unconscious almost immediately - the first stages of hypoxia kick in within seconds. They would have regained consciousness as the plane descended below 10 000 feet, at which point the briefcase/seal would have been unnecessary.
Correction: Hypoxia does not kick in within seconds, it depends very much from person to person but most will be able to work for close to a minute. A physically fit person may work well for over a minute without getting more oxygen in a full breath. At flight altitude the pressure is also not zero, so some oxygen will be gotten still.
Corrected entry: The woman in the control tower states that the 747-200 is the most sophisticated airliner around. No it isn't. This film was made in 1997. In 1997 we had Concorde (a little more sophisticated) and we had Airbus, the most automated and computerized airliner around. We also had newer versions of the 747, which were more sophisticated.
Correction: Well the person may have been intentionally trying to make the girl flying the plane feel better and safer, or it may have simply been a character mistake where she meant to say "ONE of the most sophisticated airliners around". Both are very possible.
Corrected entry: The aircraft is in cruise for a lot of the film, at around 35,000 feet. However, when Teri comes to try and land the plane, it just happens to be at the correct altitude to begin an approach (about 2,500 feet). When did the descent happen?
Correction: The change in altitude would have taken place immediately after the prisoner fired his gun and blew a hole in the skin of the plane. When an aircraft decompresses at altitude, the pilot immediately dives to 10,000 feet or lower. Otherwise, the passengers would suffer hypoxia and die within minutes. Although it didn't figure into the story, that would be the most logical explanation.
Corrected entry: For some reason, the 747 - one of the largest airliners around - manages to fully flip upside-down in the storm. This is difficult for a trained pilot to do, let alone wind. In order for this to happen, both ailerons need to have been configured for a bank (which they weren't) in order for it to physically rotate in the first place, and the rudder would also had to have been configured so that the aircraft did not change heading (which it didn't). Not ONLY that, the autopilot was engaged, which would have stopped this happening. Even if it DID happen (which it wouldn't), the autopilot would not be able to reposition the aircraft back to normal.
Correction: An extreme storm could turn the plane over without manipulating the control surfaces or caring whether the autopilot is on or off. Micro-burst down on one side, micro-burst up on the other - voila! Plane is rotated.
Correction: The masks drop first when the cabin altitude (pressure in the cabin) goes above 10 000 ft. If the leak is small or if the hole is sealed by something (for example a suitcase) it may not drop the pressure very much, as the pressure is regulated by valves controlling both inflow from the engines and outflow from the cabin.