The Commission reported a year later that audiotapes from NORAD 's Northeast headquarters and other evidence showed clearly that the military never had any of the hijacked airliners in its sights and at one point chased a phantom aircraft — American Airlines Flight 11 — long after it had crashed into the World Trade Center . For example , Maj. Gen. Larry Arnold and Col. Alan Scott told the commission that NORAD had begun tracking United 93 at 9:16 a.m. , but the commission determined that the airliner was not even hijacked until 12 minutes later . According to later testimony , the military was not aware of the flight until after it had crashed in Pennsylvania
American Airlines Flight 11
American Airlines Flight 11
Criticism of the 9/11 Commission