The airliner on take off is not a 747 but a T-Tail design airliner.
In the 69th minutes Shatner is sucked out of the airplane door. Seconds before, he was nowhere near the door.
In the 20th minute a stewardess is seen preparing food in a common seating area (not a private, hygienic area). She then walks with a tray offering canapes. On a commercial airliner, none of this would happen.
In the 63rd minute, they use torches on the plane. These would have triggered alarms and possibly sprinklers.
In the 18th minute the captain requests from air traffic control (ATC) a change in course to which ATC does not reply. ATC allows permission for a pilot to make a change in course, altitude, etc.
In any of the shots of the jet, there is now tail wing number (combination of alpha numeric characters). This is mandatory FAA regulation.
The little girl is far too young to be travelling alone and would not be allowed to do so on a commercial airliner without an adult.
Visible wire pulling open the crack in the floor.
Although supposedly belonging to fictional airline "AoA", the Transworld Airlines logo can be seen on the plane used in several ground shots.