Cillian Murphy wanted the role of Jackson so badly that he took a plane from England to Hollywood two days before his wedding to have lunch with Wes Craven. Craven later gave him the part saying that his eyes won him over.
(at around 10 mins) When a woman spills an iced cappuccino on Lisa, the expression on Rachel McAdams's face is real surprise, not acted. She did not know that the beverage would be so cold.
For the movie, fake airline tickets were printed up for passengers to carry and use. On the back was listed 12 "terms and conditions" for buying the ticket, just like on real airline tickets. However, the twelfth read: "All the provisions of this Passenger Ticket and Baggage Claim Check are completely bogus. It's all a bunch of excessive detail, and if you happen to be reading this you've got too much time on your hands. Bring a good book next time."
As mentioned by Wes Craven in the "making of", the lady that plays the irate customer in the beginning and end of the film was cast after Craven met her at a board meeting. He had a feeling that she would make an excellent irate customer from her persona, walked up to her after the meeting, and asked her to be in his movie. She eventually agreed.
The entire airplane set was built on hydraulics so when turbulence was called for in the script, the set actually shook from side to side.