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

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Senior United Airlines personnel are, unusually, not informed about air traffic control communications with Flight 175. At 8:41 a.m., the pilots of Flight 175 reported to air traffic controllers that they heard “a suspicious transmission” from another aircraft during their departure out of Boston (see 8:41 a.m.-8:42 a.m. September 11, 2001). Yet the details of this communication with Flight 175 are not passed on to personnel at the United Airlines System Operations Control (SOC) center, just outside Chicago. [9/11 Commission, 8/26/2004, pp. 20]
Manager Receives 'No Relevant Information about the Hijackings' - Rich Miles, the manager on duty at the SOC, will later tell the 9/11 Commission that “[w]hile his experience and expectation was that [FAA air traffic control] would communicate to him and to the SOC about ‘strange’ or unusual communications from the cockpit… he could not recall any such communications on 9/11.” He will say that although, “typically, he would receive relevant information from the [air traffic control] system,” he receives “no relevant information about the hijackings” on this day. [9/11 Commission, 11/21/2003 pdf file]
Other Airline Personnel Unaware of Flight 175 Communications - None of the other senior United Airlines officials on duty at the SOC are told about the 8:41 a.m. report made by the pilots of Flight 175. [9/11 Commission, 8/26/2004, pp. 20] These officials will tell the 9/11 Commission that “the dispatchers and managers at the SOC” are in fact “not aware of any communications” between FAA controllers and Flight 175 this morning. [9/11 Commission, 11/20/2003 pdf file] The 9/11 Commission will describe, “SOC personnel at United that we talked to had no idea of the extent of interaction of the [Flight 175] crew with the saga of [Flight 11].” The Commission will add, “We walked down a list of indicators,” but state, “Until we mentioned them, no one we talked to [at United Airlines] was aware of those occurrences.” [9/11 Commission, 11/17/2003 pdf file]
Controllers Communicate with Pilots, Not Dispatchers - The United Airlines officials will say, however, that, “first and foremost,” FAA controllers “communicated directly with airline pilots, not the dispatchers” at the airline. [9/11 Commission, 11/20/2003 pdf file] Ed Ballinger, the United Airlines dispatcher responsible for Flight 175, will comment that “he did not feel that [air traffic control] was under any obligation to share such information [as the details of the 8:41 a.m. communication] with him, because it didn’t apparently affect the safety of any of his flights.” [9/11 Commission, 4/14/2003 pdf file]
Airline Not Advised to Notify Other Planes about Hijackings - The United Airlines officials who talk with the 9/11 Commission will also recall that “they never received any communication… from the FAA or the air traffic control system advising United to contact its aircraft about the hijackings.” The 9/11 Commission will not offer any explanation for the lack of communication between air traffic control and United Airlines. [9/11 Commission, 8/26/2004, pp. 20]

Entity Tags: Federal Aviation Administration, United Airlines, Rich Miles, Ed Ballinger

Timeline Tags: Complete 911 Timeline, 9/11 Timeline

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]

Entity Tags: United Airlines, New York Air Route Traffic Control Center

Timeline Tags: Complete 911 Timeline, 9/11 Timeline

Ed Ballinger.Ed Ballinger. [Source: CNN]At the United Airlines System Operations Control (SOC) center outside Chicago, flight dispatcher Ed Ballinger learns that Flight 175 is suspected as being hijacked, and then sends text messages to try and make contact with it. [9/11 Commission, 8/26/2004, pp. 23-24] The SOC center has just been contacted by the United Airlines maintenance office in San Francisco, about a call it received from an attendant on Flight 175, who had reported that their plane had been hijacked (see Shortly Before 9:00 a.m. September 11, 2001). [Wall Street Journal, 10/15/2001] Subsequently, around 9:01 or 9:02, a dispatch manager at the SOC goes to Ballinger’s desk and informs him of the details of this call. [9/11 Commission, 8/26/2004, pp. 23] Ballinger is the flight dispatcher responsible for United’s aircraft flying from the East Coast to the West Coast, which include Flight 175 (and also Flight 93). [Chicago Daily Herald, 4/14/2004] At 9:03, he sends an ACARS message to Flight 175: “How is the ride. Anything dispatch can do for you.” (ACARS is an e-mail system that enables personnel on the ground to rapidly communicate with those in the cockpit of an aircraft.) At the same time, the United Airlines air traffic control coordinator also sends an ACARS message to the flight: “NY approach lookin for ya on [frequency] 127.4.” Just after 9:03, unaware it has now crashed into the World Trade Center, Ballinger and the air traffic control coordinator re-send these ACARS messages to Flight 175. [9/11 Commission, 8/26/2004, pp. 9 and 23-24] Twenty minutes later, Ballinger will remain unaware that Flight 175 has crashed and still be trying to contact it by ACARS (see 9:23 a.m. September 11, 2001). [9/11 Commission, 8/26/2004, pp. 26] All airlines have a staff of dispatchers like Ballinger who, under FAA rules, are responsible for monitoring aircraft in flight. They follow each flight’s progress, relay safety information, and handle any problems that arise. [Spencer, 2008, pp. 14 and 35] United Airlines dispatchers typically monitor up to two dozen flights at once. [Longman, 2002, pp. 68] Ballinger has 16 transcontinental flights taking off early this morning that he is responsible for. [New York Observer, 6/20/2004]

Entity Tags: Ed Ballinger

Timeline Tags: Complete 911 Timeline, 9/11 Timeline


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