Delta Air Lines instructs one of its aircraft, Flight 1989, to land at Cleveland Hopkins Airport, but the FAA’s Cleveland Center, which is handling the aircraft, is not notified of this. [USA Today, 8/13/2002; Associated Press, 8/15/2002]
Pilots Instructed to Land – The pilots of Delta 1989 receive an ACARS text message from their airline’s dispatch office in Atlanta, Georgia, instructing them to “Land immediately in Cleveland.” [Spencer, 2008, pp. 167] According to USA Today, “Since early reports that a bomb, then hijackers, might be aboard” Delta 1989, Delta Air Lines’ headquarters in Atlanta has been tracking the flight, and receiving reports on it every five minutes. [USA Today, 8/13/2002] The plane’s pilot, Captain Paul Werner, quickly types a response to the message, “ok.” But, a couple of minutes later, he receives another ACARS message from the airline. It says: “Confirm landing in Cleveland. Use correct phraseology.” Werner and First Officer David Dunlap are puzzled. According to author Lynn Spencer: “There’s such a thing as correct phraseology on the radio, but there is no such thing when typing back and forth with dispatch on ACARS. Those messages are usually casual.” Werner carefully types a response: “Roger. Affirmative. Delta 1989 is diverting to Cleveland.” He calls the Cleveland Center at 9:44 a.m. and requests a diversion to Cleveland Airport. [Spencer, 2008, pp. 167-168; USA Today, 9/11/2008]
Cleveland Center Not Informed – About 15 minutes earlier, Cleveland Center heard the sounds from Flight 93 as it was being hijacked, but initially thought these came from Delta 1989, and mistakenly believed the Delta flight was being taken over (see (9:28 a.m.-9:33 a.m.) September 11, 2001). [USA Today, 8/13/2002] But the Delta pilots’ normal responses to radio transmissions soon led air traffic controller John Werth, who is handling Delta 1989, to conclude that this aircraft was fine. [USA Today, 9/11/2008] However, controllers at the Cleveland Center are unaware that Delta Air Lines has instructed Flight 1989 to land, and so Werner’s request for a change of course will make them suspicious of it again (see (Shortly After 9:44 a.m.) September 11, 2001). [USA Today, 8/13/2002]