Kenneth Kantymir (who played Andrew Garcia, one of the passengers who rushed the cockpit) wore his own Star of Courage bravery medal pinned over his heart for the entire shoot to honor the memory of the heroic passengers and crew of United Airlines flight 93.
Early in the movie you can hear a flight attendant on the phone replying to the person asking can you look out the window and tell us where you are her response see water, see buildings were low, were flying way too low, were flying very very low those are the last words of actual American Airlines flight attendant Amy Sweeney who was on Flight 11 from Boston To Los Angeles that morning.
The FAA Center mention in the film is honestly, the Boston Air Route Traffic Control Center (ZBW), and surprisingly, located in located in Nashua, New Hampshire, United States. The Boston ARTCC covers 165,000 square miles (430,000 km2) of airspace that includes airports in Connecticut, Vermont, Massachusetts, Rhode Island, Maine, New Hampshire, New York state and northeast Pennsylvania.
The plane that first hit the World Trade Center was American Airlines Flight 11. The second plane, United Airlines Flight 175 struck the South Tower 17 minutes later at 9:03am, September 11th, 2001. This is follow by American Airlines Flight 77, that crashed into the Pentagon.
Despite playing Ziad Jarrah, who was Lebanese, Dominic Rains (born Amin Nazemzadeh) is Iranian.