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(9:00 a.m.) September 11, 2001: United Airlines Learns Flight 175 Is Missing from Radar

2001-09-11

The FAA’s New York Center informs the air traffic control coordinator at United Airlines’ headquarters, outside Chicago, that Flight 175 is missing from radar. Although Flight 175’s transponder signal changed at around 8:47 (see 8:46 a.m.-8:47 a.m. September 11, 2001), according to the 9/11 Commission the air traffic controller handling the flight only noticed the change at 8:51 (see 8:51 a.m.-8:53 a.m. September 11, 2001). [9/11 Commission, 8/26/2004, pp. 21-22 pdf file]