(9:30 a.m.) September 11, 2001: Air Traffic Control Notifies United Airlines about Flight 93

The FAA’s Cleveland Center notifies United Airlines’ headquarters, near Chicago, that Flight 93 is not responding to attempted radio contacts. [9/11 Commission, 8/26/2004, pp. 39 ] Cleveland Center made its last normal communication with Flight 93 at 9:27 (see 9:27 a.m. September 11, 2001). [9/11 Commission, 7/24/2004, pp. 28] After the hijacking began at around 9:28, the controller handling Flight 93, John Werth, tried unsuccessfully to re-establish contact with it. [Gregor, 12/21/2001 ; CBS News, 9/10/2006] The lack of response from Flight 93, combined with the plane’s turning to the east (see (9:36 a.m.) September 11, 2001), will lead United to believe, by 9:36 a.m., that it has been hijacked. [9/11 Commission, 7/24/2004, pp. 456]