This is Broll footage from a documentary about air traffic control, filmed at Chicago O'Hare Tower. Don't know the name of the documentary, never saw it, and just guessing as to when it was filmed. Based on the people on duty in the tower, it was definitely poststrike (1981), and prior to 1995. The controller in the thumbnail is the late Donna King; I'm the guy at 27:59 that relieved her on the North Local position.