The Real Aircraft:

A real American Airlines 747-123 (N9675) was used in the movie, painted in the fictional Columbia Airlines colors. No wonder the colors of American and Columbia look so much alike (except for the red stripe that dissapears in the latter).The plane is a "combi" aircraft with a cargo section at the back, as the loading door and the small passenger cabin demonstrate.
 N9675, a Boeing 747-123 (msn/ln 20390/136), delivered on May 7, 1971, was operated at the time by American Airlines and later became an all-freight plane (flying as "American Freighter"). It temporarily had the registry OD-AGM for a lease. When American Airlines disposed of its 747 fleet, it was sold to UPS which now flies it as N675UP.