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Context of '8:51 a.m.-8:53 a.m. September 11, 2001: Air Traffic Controller Declares Flight 175 as Possibly Hijacked'

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Personnel at United Airlines’ headquarters, near Chicago, are subjected to a surprise training exercise in which they are led to believe that one of their planes has crashed, and their experience with this exercise allegedly means they will be better able to respond to the 9/11 attacks. (Levin, Adams, and Morrison 8/12/2002; 9/11 Commission 11/20/2003 pdf file; Studdert 5/26/2015 pdf file; Becker 11/12/2015)
Manager Is Concerned that the Airline Is Unprepared for an Accident - Andy Studdert, United Airlines’ chief operating officer, has been concerned that, since it hasn’t suffered a real accident in over 15 years, United Airlines is unprepared to respond properly should one occur now. “I was worried we’d become cocky,” he will later comment. “We thought it couldn’t happen to us.” Around March this year, therefore, he told the airline’s other managers, “One of these days, I’m gonna come in here and I’m gonna do a no-notice drill.” (Center for Values-Driven Leadership 3/15/2012; Johnson 4/26/2012) A “no-notice” drill is an exercise that is conducted without its participants being given any formal advance notice of when it will occur. (US Department of Justice 5/21/2000; Inglesby, Grossman, and O'Toole 2/1/2001; Oak Ridge Institute for Science and Education 10/15/2011)
Pilot Is Told to Pretend His Plane Is Experiencing an Emergency - Today, Studdert holds this no-notice exercise. Only a few people know about it in advance. Studdert tells a United Airlines employee who he will refer to as his “safety guy” to contact the pilot of a flight to Australia and give them some instructions. The pilot is therefore told he needs to call in during his flight and report an emergency. He should say there is an “uncontained number three engine failure, rapid descent, decompression,” but stop talking halfway through the word “decompression” and then go silent. He should also turn off the plane’s transponder. (Center for Values-Driven Leadership 3/15/2012; Becker 11/12/2015) (A transponder is a device that sends an aircraft’s identifying information, speed, and altitude to air traffic controllers’ radar screens. (Maraniss 9/16/2001) )
Airline Personnel Think One of Their Planes Has Crashed - The simulated emergency takes places this afternoon. At around 2 o’clock, Studdert is interrupted by his secretary, Maryann Irving, who rushes into his office and tells him a Boeing 747 has lost contact while flying over the Pacific Ocean. In response, he runs to the airline’s operations center. (Mccartney and Carey 10/15/2001; Center for Values-Driven Leadership 3/15/2012) Airline employees believe the apparently troubled aircraft has crashed. Some of them are upset and some become physically ill. (Becker 11/12/2015) “There are people throwing up in the hall; there are people crying; there are people just staring out the windows,” Studdert will describe.
Personnel Think the Crisis Is Real for 30 Minutes - Since no one in the operations center is able to contact the apparently troubled aircraft, Studdert opens the airline’s crisis center. (Center for Values-Driven Leadership 3/15/2012) The crisis center, according to journalist and author Jere Longman, is “a terraced, theater-like room that resembled NASA’s Mission Control.” (Longman 2002, pp. 77) Opening it, according to Studdert, is a significant course of action. When this happens, everyone working for the airline becomes responsible either for running the airline or acting to support the management of the emergency. This means that “3,000 people are put on an immediate activation.” (Center for Values-Driven Leadership 4/23/2012) United Airlines employees believe one of their planes has crashed for about 30 minutes and then Studdert reveals that the apparent catastrophe is just an exercise scenario. (Levin, Adams, and Morrison 8/12/2002) He gets on the crisis center’s communications link, which, he will say, “has got 170 stations and people all over the country, all over the world,” and announces, “This has been a no-notice drill; there is no event; everything’s fine.”
Employees Are Furious about the Exercise - The reaction to the exercise in the days after it takes place will be particularly bitter and Studdert will face severe criticism for running it. “I had the board members calling; I had the unions demanding I be fired; I had people telling me I’m the most evil person in the world,” he will recall. (Center for Values-Driven Leadership 3/15/2012; Johnson 4/26/2012) Some employees “wanted to kill me,” he will say.
Exercise Has Similarities to the Situation Experienced on September 11 - It is unclear whether Studdert’s exercise has a beneficial or a detrimental effect on the ability of United Airlines to respond to the hijackings 12 days later, on September 11. Studdert will claim that it prepares employees to manage the events of September 11 and reveals weaknesses, such as outdated phone numbers, which are quickly corrected. (Johnson 4/26/2012; Becker 11/12/2015) “It’s amazing, after 9/11… how many people came up to me and thanked me [for running the exercise], because we were ready,” he will say. (Center for Values-Driven Leadership 3/15/2012) It is possible, however, that it will cause some United Airlines employees to initially think the reports about the terrorist attacks on September 11 are part of another exercise, although accounts are contradictory (see (8:50 a.m.-9:03 a.m.) September 11, 2001). (Levin, Adams, and Morrison 8/12/2002; Chicago Tribune 7/16/2003) The scenario of Studdert’s exercise in fact has some similarities with the situation that operations center personnel have to deal with on September 11. On that day, communication with Flight 175—the first of the two United Airlines planes that are hijacked—will be lost (see 8:51 a.m.-8:53 a.m. September 11, 2001) and the plane will have its transponder code changed, although the transponder will not be turned off (see 8:46 a.m.-8:47 a.m. September 11, 2001). (9/11 Commission 8/26/2004, pp. 20-21) Communication will subsequently be lost with Flight 93—the second United Airlines plane to be hijacked (see 9:27 a.m. September 11, 2001 and (9:29 a.m.) September 11, 2001)—and that plane’s transponder will be turned off (see (9:40 a.m.) September 11, 2001). (9/11 Commission 8/26/2004, pp. 38-39, 43)
Crisis Center Holds Quarterly Exercises - The United Airlines crisis center usually runs exercises four times a year. Most of these deal with safety issues, but security scenarios are also rehearsed, according to Ed Soliday, the airline’s vice president of safety and security. Typically, the 9/11 Commission will be told, these exercises “are scripted” and based around an act of bioterrorism or an international incident. United Airlines has also practiced hijacking scenarios, according to Soliday, although none of these dealt with the threat of an aircraft being used as a weapon. (9/11 Commission 11/20/2003 pdf file; 9/11 Commission 11/21/2003 pdf file)

Colin Scoggins, the military liaison at the FAA’s Boston Center, calls the FAA’s New York Center but is quickly cut off when the air traffic controller who answers says the center is busy dealing with a hijacking. According to author Lynn Spencer, Scoggins “calls New York Center to notify them that American 11 appears to be descending toward New York, most likely to land at JFK” International Airport. But the controller who takes the call snaps at him: “We’re too busy to talk. We’re working a hijack,” and then hangs up. According to Spencer, the New York Center controller is referring to Flight 175, but “Scoggins just figures that he’s talking about American 11. He has no idea that a second airliner is in crisis.” However, the timing of this call is unclear. If it is made while Flight 11 is descending toward New York, this would mean it occurs in the minutes before 8:46, when Flight 11 crashes (see 8:46 a.m. September 11, 2001). But in Spencer’s account, the call is made just after New York Center controller Dave Bottiglia notices that Flight 175’s transponder code has changed and he calls out to another controller, “I can’t get a hold of UAL 175 at all right now and I don’t know where he went to” (see 8:51 a.m.-8:53 a.m. September 11, 2001). (Spencer 2008, pp. 48-49) The transcript of radio communications between the New York Center and Flight 175 shows that this would mean Scoggins’s call occurs around 8:53 a.m.-8:54 a.m., about seven minutes after Flight 11 crashes. (New York Times 10/16/2001)

After 9/11, NORAD and other sources will claim that NORAD’s Northeast Air Defense Sector (NEADS) is notified at this time that Flight 175 has been hijacked. (Washington Post 9/12/2001; CNN 9/17/2001; North American Aerospace Defense Command 9/18/2001; Kugler 8/19/2002; Adcock 9/10/2002) However, the FAA’s New York Center, which is handling Flight 175, first alerts its military liaison about the hijacking at around 9:01 (see 9:01 a.m.-9:02 a.m. September 11, 2001). In addition, according to the 9/11 Commission, NEADS is not informed until two minutes later (see (9:03 a.m.) September 11, 2001). (9/11 Commission 6/17/2004) According to the Commission, the first “operational evidence” that there is something wrong on Flight 175 is not until 8:47, when its transponder code changes (see 8:46 a.m.-8:47 a.m. September 11, 2001), and it is not until 8:53 that the air traffic controller handling it concludes that Flight 175 may be hijacked (see 8:51 a.m.-8:53 a.m. September 11, 2001). (9/11 Commission 7/24/2004, pp. 7, 21-22)

Flight 175 stops transmitting its transponder signal. It is currently flying near the New Jersey-Pennsylvania border. (Ellison 10/17/2001; Adcock 9/10/2002; 9/11 Commission 6/17/2004) However, the transponder is turned off for only about 30 seconds, and then comes back on as a signal that is not designated for any plane on this day. Then, within the space of a minute, it is changed to another new code. But New York Center air traffic computers do not correlate either of these new transponder codes with Flight 175. Consequently, according to an early FAA report, “the secondary radar return (transponder) indicating aircraft speed, altitude, and flight information began to coast and was no longer associated with the primary radar return.” Therefore, while controllers are able “to track the intruder easily… they couldn’t identify it.” However, Dave Bottiglia, the New York Center air traffic controller responsible for Flight 175, is currently trying to locate the already-crashed Flight 11, and therefore supposedly does not notice the transponder code changes on Flight 175 until 8:51 a.m. (see 8:51 a.m.-8:53 a.m. September 11, 2001). (Federal Aviation Administration 9/17/2001 pdf file; Lane, Phillips, and Snyder 9/17/2001; 9/11 Commission 8/26/2004, pp. 21) According to a “Flight Path Study” by the National Transportation Safety Board, the change of Flight 175’s transponder code is the “first indication of deviation from normal routine.” (National Transportation Safety Board 2/19/2002 pdf file)

Curt Applegate sitting next to his air traffic control terminal.Curt Applegate sitting next to his air traffic control terminal. [Source: NBC News]After being focused on Flight 11, Dave Bottiglia, an air traffic controller at the FAA’s New York Center, first notices problems with Flight 175. (MSNBC 9/11/2002; 9/11 Commission 7/24/2004, pp. 21) Both Flight 11 and Flight 175 have been in the airspace that Bottiglia is responsible for monitoring (see 8:40 a.m. September 11, 2001 and (8:42 a.m.-8:46 a.m.) September 11, 2001). Bottiglia has just watched Flight 11’s radar blip disappear, which means the plane has dipped below his radar’s coverage area, so is below 2,000 feet. But he does not yet realize it has crashed. He says aloud, “Well, we know he’s not high altitude anymore.” (MSNBC 9/11/2002; Spencer 2008, pp. 37) Around this time, Flight 175’s transponder changes twice in the space of a minute (see 8:46 a.m.-8:47 a.m. September 11, 2001).
Conflicting Accounts - According to MSNBC, “within seconds” of losing Flight 11’s blip, “Bottiglia has another unexpected problem.” While looking for Flight 11, he realizes that Flight 175 is also missing, and “instinctively… knows the two [planes] are somehow related.” He asks another controller to take over all of his other planes. (MSNBC 9/11/2002) But according to the 9/11 Commission’s account, Bottiglia is still trying to locate Flight 11 after it crashes, and so it is not until 8:51 a.m. that he notices the problem with Flight 175 (see 8:51 a.m.-8:53 a.m. September 11, 2001). (9/11 Commission 8/26/2004, pp. 21)
'An Intruder over Allentown' - Around the time Flight 175 changes its transponder code, air traffic controller Curt Applegate, who is sitting at the radar bank next to Bottiglia’s, sees a blip that might be the missing Flight 11. He shouts out: “Look. There’s an intruder over Allentown.” According to the Washington Post, “In air traffic jargon, an ‘intruder’ is a plane with an operating transponder that has entered restricted airspace without permission.” In fact, it is the missing Flight 175. (Lane, Phillips, and Snyder 9/17/2001; MSNBC 9/11/2002) However, these accounts make no mention of NORAD being notified about the problems with Flight 175 at this time. But according to a NORAD timeline released shortly after 9/11, NORAD’s Northeast Air Defense Sector (NEADS) was alerted about Flight 175 by the FAA several minutes earlier, at 8:43 a.m. (see 8:43 a.m. September 11, 2001). (North American Aerospace Defense Command 9/18/2001)

According to the 9/11 Commission, Dave Bottiglia, the air traffic controller handling Flight 175, only notices now that this flight’s transponder signal has changed (see 8:46 a.m.-8:47 a.m. September 11, 2001). Bottiglia asks Flight 175 to return to its proper transponder code. There is no response. Beginning at 8:52 a.m., he makes repeated attempts to contact it, but there is still no response. Bottiglia contacts another controller at 8:53 a.m., and says: “We may have a hijack. We have some problems over here right now.… I can’t get a hold of UAL 175 at all right now and I don’t know where he went to.” (New York Times 10/16/2001; 9/11 Commission 6/17/2004; Spencer 2008, pp. 48) This account apparently conflicts with earlier accounts that claim NORAD’s Northeast Air Defense Sector (NEADS) was notified at 8:43 a.m. that Flight 175 had been hijacked (see 8:43 a.m. September 11, 2001). (North American Aerospace Defense Command 9/18/2001)

The head air traffic controller at the FAA’s New York Center notifies a manager at the facility that she believes Flight 175 has been hijacked. The manager tries to notify regional managers about this, but cannot reach them because they are discussing the hijacking of Flight 11 and refuse to be disturbed. However, even though the controller managing Flight 175 said, “we may have a hijack” at 8:53 a.m. (see 8:51 a.m.-8:53 a.m. September 11, 2001), the 9/11 Commission will conclude that NORAD’s Northeast Air Defense Sector (NEADS) is not notified about the aircraft until 9:03 a.m. (see (9:03 a.m.) September 11, 2001). (9/11 Commission 6/17/2004) The Commission’s account will conflict with previous accounts that state that NEADS was notified of the Flight 175 hijacking at 8:43 a.m. (see 8:43 a.m. September 11, 2001). The head of the New York Center, Mike McCormick, has already decided at 8:52 a.m. that Flight 175 has been hijacked and is on a suicide run to New York City (see (8:52 a.m.) September 11, 2001). (CNN 8/12/2002)

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)

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