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Context of '(8:34 a.m.) September 11, 2001: Air Traffic Controller Takes over Monitoring Flight 11, but Is Unaware It Is Hijacked'

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Shortly after air traffic controllers ask Flight 11 to climb to 35,000 feet, its transponder stops transmitting. A transponder is an electronic device that identifies a plane on a controller’s screen and gives its exact location and altitude. Among other vital functions, it is also used to transmit a four-digit emergency hijack code. Flight control manager Glenn Michael later says, “We considered it at that time to be a possible hijacking.” [Christian Science Monitor, 9/13/2001; MSNBC, 9/15/2001; Associated Press, 8/12/2002] Initial stories after 9/11 suggest the transponder is turned off around 8:13 a.m., but Pete Zalewski, the air traffic controller handling the flight, later says the transponder is turned off at 8:20 a.m. [MSNBC, 9/11/2002] The 9/11 Commission places it at 8:21 a.m. [9/11 Commission, 6/17/2004] Colonel Robert Marr, head of NEADS, claims the transponder is turned off some time after 8:30 a.m. where the Flight 11 hijack was first detected a.m. [ABC News, 9/11/2002]

Entity Tags: Pete Zalewski, Glenn Michael, Robert Marr

Timeline Tags: Complete 911 Timeline, 9/11 Timeline

After Flight 11 fails to respond to an instruction from air traffic control to climb to 35,000 feet (see 8:13 a.m. September 11, 2001), the controller handling it, Pete Zalewski, tries to regain contact with the aircraft. Over the following ten minutes, he makes numerous attempts but without success. (Zalewski says he makes 12 attempts; the 9/11 Commission says nine.) He tries reaching the pilot on the emergency frequency. Zalewski later recalls that initially, “I was just thinking that it was, you know, maybe they—pilots weren’t paying attention, or there’s something wrong with the frequency.… And at first it was pretty much, you know, ‘American 11,’ you know, ‘are you paying attention? Are you listening?’ And there was still no response.” He says, “I went back to the previous sector to see if the pilot had accidentally flipped the switch back over on the—on the radio.” But as Zalewski is repeatedly unable to get any response from Flight 11, he recalls, “I even began to get more concerned.” However, Zalewski claims, it is not until he sees the plane’s transponder go off at around 8:21 that he suspects something is “seriously wrong,” and calls his supervisor for assistance (see (8:21 a.m.) September 11, 2001). And it is not until about 8:25 that he realizes for sure that he is dealing with a hijacking (see (8:25 a.m.) September 11, 2001). It is only then that Boston Center starts notifying its chain of command that Flight 11 has been hijacked (see 8:25 a.m. September 11, 2001). [New York Times, 10/16/2001; MSNBC, 9/11/2002; 9/11 Commission, 7/24/2004, pp. 18; 9/11 Commission, 8/26/2004, pp. 7 and 10-11 pdf file]

Entity Tags: Pete Zalewski

Timeline Tags: Complete 911 Timeline, 9/11 Timeline

FAA’s Boston CenterFAA’s Boston Center [Source: ABC News]According to some reports, Boston flight control decides that Flight 11 has probably been hijacked, but apparently, it does not notify other flight control centers for another five minutes, and does not notify NORAD for approximately 20 minutes. [New York Times, 9/15/2001; Newsday, 9/23/2001] ABC News will later say, “There doesn’t seem to have been alarm bells going off, [flight] controllers getting on with law enforcement or the military. There’s a gap there that will have to be investigated.” [ABC News, 9/14/2001] (Note the conflicting account at 8:21 a.m. (see (8:21 a.m.) September 11, 2001)

Entity Tags: Boston Air Route Traffic Control Center

Timeline Tags: Complete 911 Timeline, 9/11 Timeline

Tom Roberts.Tom Roberts. [Source: NBC News]Boston flight controller Pete Zalewski, handling Flight 11, sees that the flight is off course and that the plane has turned off both transponder and radio. Zalewski later claims he turns to his supervisor and says, “Would you please come over here? I think something is seriously wrong with this plane. I don’t know what. It’s either mechanical, electrical, I think, but I’m not sure.” When asked if he suspected a hijacking at this point, he replies, “Absolutely not. No way.” According to the 9/11 Commission, “the supervisor instructed the controller [presumably Zalewski] to follow standard operating procedures for handling a ‘no radio’ aircraft once the controller told the supervisor the transponder had been turned off.” Another flight controller, Tom Roberts, has another nearby American Airlines Flight try to contact Flight 11. There is still no response. The flight is now “drastically off course” but NORAD is still not notified. [MSNBC, 9/11/2002; 9/11 Commission, 6/17/2004] Note that this response contradicts flight control manager Glenn Michael’s assertion that Flight 11 was considered a possible hijacking as soon as the transponder was discovered turned off.

Entity Tags: Pete Zalewski, Tom Roberts, Glenn Michael, North American Aerospace Defense Command

Timeline Tags: Complete 911 Timeline, 9/11 Timeline

Pete Zalewski.Pete Zalewski. [Source: NBC]Because the talkback button on Flight 11 has been activated, Boston Center air traffic controllers can hear a hijacker on board say to the passengers: “We have some planes. Just stay quiet and you’ll be OK. We are returning to the airport.” [Boston Globe, 11/23/2001; 9/11 Commission, 7/24/2004, pp. 19] Air traffic controller Pete Zalewski recognizes this as a foreign, Middle Eastern-sounding voice, but does not make out the specific words “we have some planes.” He responds, “Who’s trying to call me?” Seconds later, in the next transmission, the hijacker continues: “Nobody move. Everything will be OK. If you try to make any moves you’ll endanger yourself and the airplane. Just stay quiet.” [New York Times, 10/16/2001; 9/11 Commission, 6/17/2004; MSNBC, 9/9/2006] Bill Peacock, the FAA director of air traffic services, later claims, “We didn’t know where the transmission came from, what was said and who said it.” David Canoles, the FAA’s manager of air traffic evaluations and investigations, adds: “The broadcast wasn’t attributed to a flight. Nobody gave a flight number.” [Washington Times, 9/11/2002] Similarly, an early FAA report will state that both these transmissions came from “an unknown origin.” [Federal Aviation Administration, 9/17/2001 pdf file] Zalewski asks for an assistant to help listen to the transmissions coming from the plane, and puts its frequency on speakers so others at Boston Center can hear. Because Zalewski didn’t understand the initial hijacker communication from Flight 11, the manager of Boston Center instructs the center’s quality assurance specialist to “pull the tape” of the transmission, listen to it carefully, and then report back. They do this, and by about 9:03 a.m. a Boston manager will report having deciphered what was said in the first hijacker transmission (see 9:03 a.m. September 11, 2001). [9/11 Commission, 6/17/2004; MSNBC, 9/9/2006] Fellow Boston controller Don Jeffroy also hears the tape of the hijacker transmissions, though he doesn’t state at what time. He says: “I heard exactly what Pete [Zalewski] heard. And we had to actually listen to it a couple of times just to make sure that we were hearing what we heard.” [MSNBC, 9/11/2002] At some point, Ben Sliney, the national operations manager at the FAA’s Herndon Command Center, gets word of the “We have some planes” message, and later says the phrase haunts him all morning. American Airlines Executive Vice President for Operations Gerard Arpey is also informed of the “strange transmissions from Flight 11” at some point prior to when it crashes at 8:46 a.m. [USA Today, 8/13/2002] Boston Center will receive a third transmission from Flight 11 about ten minutes later (see (8:34 a.m.) September 11, 2001).

Entity Tags: Bill Peacock, Boston Air Route Traffic Control Center, David Canoles, Pete Zalewski

Timeline Tags: Complete 911 Timeline, 9/11 Timeline

According to Terry Biggio, the operations manager at the FAA’s Boston Center, the center initially thought Flight 11 “was a catastrophic electrical failure and… was diverting to New York” (see (8:21 a.m.) September 11, 2001). [Federal Aviation Administration, 10/19/2002] However, at about 8:24 a.m., controllers heard two radio transmissions from it, with the voice of a hijacker declaring, “We have some planes” (see 8:24 a.m. September 11, 2001). Pete Zalewski, who is handling Flight 11, says that after the second of these: “I immediately knew something was very wrong. And I knew it was a hijack.” He alerts his supervisor. Lino Martins, another Boston air traffic controller, says, “the supervisor came over, and that’s when we realized something was serious.” [Christian Science Monitor, 9/13/2001; MSNBC, 9/11/2002; 9/11 Commission, 6/17/2004] However, two senior FAA officials—Bill Peacock and David Canoles—later say that the hijacker transmissions were not attributed to a flight, so controllers didn’t know their origin. [Washington Times, 9/11/2002] An early FAA report will similarly refer to them as having come “from an unknown origin.” But right away, the center begins notifying the chain of command that a suspected hijacking is taking place (see 8:25 a.m. September 11, 2001). [Federal Aviation Administration, 9/17/2001 pdf file] However, some reports claim that controllers decided Flight 11 was probably hijacked earlier than this, by about 8:20 a.m. (see (8:20 a.m.) September 11, 2001).

Entity Tags: Pete Zalewski, Lino Martins

Timeline Tags: Complete 911 Timeline, 9/11 Timeline

John Hartling.John Hartling. [Source: NBC News]By 8:34 a.m., Flight 11 has entered airspace managed by Boston Center air traffic controller John Hartling. [MSNBC, 9/11/2002; 9/11 Commission, 7/24/2004, pp. 19] Although Boston controller Pete Zalewski, who was managing Flight 11, concluded the plane was hijacked almost ten minutes earlier (see (8:25 a.m.) September 11, 2001), at the time the blip for Flight 11 appears on Hartling’s radar screen, Hartling is unaware that a hijacking is taking place. According to author Lynn Spencer, the reason is that “The concentration required for the job is so intense that controllers operate on a need-to-know basis. They don’t need to know what’s happening in other controllers’ sectors unless it might affect their own airspace, and distractions are rigorously kept to a minimum.” Tom Roberts, another Boston Center controller, has just been relieved from duty for a scheduled coffee break, and comes over to Hartling’s desk. Referring to Flight 11’s radar track, he tells Hartling, “This—this aircraft, we believe, is hijacked, and he’s last reported at 29,000 feet.” However, Hartling is incredulous. He will later recall that when Roberts says the plane is hijacked, “I didn’t believe him.” This is because “I didn’t think that that stuff would happen anymore, especially in this country.” Hartling continues tracking Flight 11 as it heads toward New York. Although its transponder has been turned off (see (Between 8:13 a.m. and 8:21 a.m.) September 11, 2001), he can tell that, at almost 600 mph, it is flying far faster than the 450 mph it should be moving at. [MSNBC, 9/11/2002; Spencer, 2008, pp. 22-24]

Entity Tags: Boston Air Route Traffic Control Center, John Hartling, Tom Roberts

Timeline Tags: Complete 911 Timeline, 9/11 Timeline

Tech. Sgt. Jeremy Powell.Tech. Sgt. Jeremy Powell. [Source: Scott A. Gwilt/ Rome Sentinel]The FAA’s Boston Center calls NORAD’s Northeast Air Defense Sector (NEADS) in Rome, NY, to alert it to the suspected hijacking of Flight 11. According to the 9/11 Commission, this is “the first notification received by the military—at any level—that American 11 had been hijacked.” [9/11 Commission, 7/24/2004, pp. 20; 9/11 Commission, 8/26/2004, pp. 13 pdf file] The call is made by Joseph Cooper, an air traffic controller at the Boston Center, and answered by Jeremy Powell, a technical sergeant on the NEADS operations floor. [Vanity Fair, 8/1/2006; Spencer, 2008, pp. 25] Beginning the call, Cooper says: “Hi. Boston Center TMU [traffic management unit], we have a problem here. We have a hijacked aircraft headed towards New York, and we need you guys to, we need someone to scramble some F-16s or something up there, help us out.” Powell replies, “Is this real-world or exercise?” Cooper answers, “No, this is not an exercise, not a test.” [9/11 Commission, 7/24/2004, pp. 20] Shortly into the call, Powell passes the phone on to Lieutenant Colonel Dawne Deskins (see (8:38 a.m.) September 11, 2001). Deskins identifies herself to Cooper, and he tells her, “We have a hijacked aircraft and I need you to get some sort of fighters out here to help us out.” [Newhouse News Service, 1/25/2002; ABC News, 9/11/2002; Bamford, 2004, pp. 8; Spencer, 2008, pp. 26]
Military Claims Call Goes against Procedure - The 1st Air Force’s official history of the response to the 9/11 attacks will later suggest that Boston Center is not following normal procedures when it makes this call to NEADS. It states: “If normal procedures had taken place… Powell probably wouldn’t have taken that phone call. Normally, the FAA would have contacted officials at the Pentagon’s National Military Command Center who would have contacted the North American Aerospace Defense Command. The secretary of defense would have had to approve the use of military assets to assist in a hijacking, always considered a law enforcement issue.” The only explanation it gives for this departure from protocol is that “nothing was normal on Sept. 11, 2001, and many say the traditional chain of command went by the wayside to get the job done.” [Filson, 2003, pp. 51]
Accounts Conflict over Time of Call - There will be some conflict between different accounts, as to when this vital call from Boston Center to NEADS occurs. An ABC News documentary will indicate it is made as early as 8:31 a.m. [ABC News, 9/11/2002] Another ABC News report will state, “Shortly after 8:30 a.m., behind the scenes, word of a possible hijacking [reaches] various stations of NORAD.” [ABC News, 9/14/2002] NEADS logs indicate the call occurs at 8:40 a.m., and NORAD will report this as the time of the call in a press release on September 18, 2001. [Federal Aviation Administration, 9/17/2001 pdf file; North American Aerospace Defense Command, 9/18/2001] The 8:40 time will be widely reported in the media prior to the 9/11 Commission’s 2004 report. [Associated Press, 8/21/2002; BBC, 9/1/2002; Newsday, 9/10/2002; CNN, 9/11/2002] But tape recordings of the NEADS operations floor that are referred to in the 9/11 Commission Report place the call at 8:37 and 52 seconds. [9/11 Commission, 7/24/2004, pp. 20; Vanity Fair, 8/1/2006] If the 8:37 a.m. time is correct, this would mean that air traffic controllers have failed to successfully notify the military until approximately 12 minutes after they became certain that Flight 11 had been hijacked (see (8:25 a.m.) September 11, 2001), 16 minutes after Flight 11’s transponder signal was lost (see (Between 8:13 a.m. and 8:21 a.m.) September 11, 2001), and 24 minutes after the plane’s pilots made their last radio contact (see 8:13 a.m. September 11, 2001). [9/11 Commission, 6/17/2004] At 8:34, the Boston Center tried contacting the military through the FAA’s Cape Cod facility, which is located on Otis Air National Guard Base, but was told that it needed to call NEADS (see 8:34 a.m. September 11, 2001). [9/11 Commission, 7/24/2004, pp. 20; Spencer, 2008, pp. 22]

Entity Tags: Boston Air Route Traffic Control Center, Dawne Deskins, North American Aerospace Defense Command, Joseph Cooper, Northeast Air Defense Sector, Jeremy Powell

Timeline Tags: Complete 911 Timeline, 9/11 Timeline

Technicians at NORAD’s Northeast Air Defense Sector (NEADS) try frantically to locate Flight 11 on their radar scopes, but are supposedly hindered by their outdated equipment. [Spencer, 2008, pp. 31-32] NEADS has just been alerted to the hijacking of Flight 11 (see (8:37 a.m.) September 11, 2001). [9/11 Commission, 7/24/2004, pp. 20] Its technicians realize they need to find the location of the hijacked plane quickly, so that the weapons team will be able to pass this information on to any fighter jets that are launched after it.
Locating Flight 11 Is a 'Grueling Process' - Author Lynn Spencer will later explain: “To identify American 11, the surveillance and ID techs must go through a grueling process. Their radar scopes are filled with hundreds of radar returns not just from aircraft but from weather systems, ground interference, and what’s called anomalous propagation—false returns caused by conditions in the atmosphere, or by such obstructions as flocks of birds. The technicians must first determine which radar data on their screens is for aircraft, which they do by monitoring its movement, which is distinctive for planes. The technician must observe for at least 36 seconds to a minute just to confirm that a blip is in fact an aircraft track. The tech must attach what’s called a tactical display number to it, which tells the computer to start tracking and identifying the target. If the target is in fact a plane, then over a period of 12-20 seconds, the computer will start to generate information on the track: heading, speed, altitude, latitude, longitude, and the identifying information being transmitted by the transponder.” However, Flight 11’s transponder has been switched off (see (Between 8:13 a.m. and 8:21 a.m.) September 11, 2001). Therefore, “With the hundreds of pieces of radar data filling their screens, and little information as to the location of the flight,” the task of locating it “is daunting.”
Radar Equipment Supposedly Unsuitable - Spencer will suggest that trying to locate Flight 11 is made more difficult because the radar equipment at NEADS is outdated and unsuited to the task at hand. She writes: “[T]he NEADS radar equipment is different from that used by air traffic controllers. It’s much older, developed in the 1970s and brought into use by NEADS in the early 1980s. The system was designed to monitor the shoreline for incoming high-altitude threats: missiles coming from across the ocean. Slow and cumbersome, and not nearly as user friendly as more modern equipment, the NEADS monochromic radar displays are not designed to take internal FAA radar data or to identify radar tracks originating from inside the United States. The system offers little, if any, such low-level coverage over the country.” [Spencer, 2008, pp. 31-32] Several of the NEADS personnel will later complain of their inability to locate Flight 11 on their scopes (see Shortly After 8:37 a.m. September 11, 2001). But Master Sergeant Joe McCain, the mission crew commander technician at NEADS, believes he has located Flight 11 on the radar screen just before it crashes into the World Trade Center (see 8:45 a.m.-8:46 a.m. September 11, 2001).

Entity Tags: Northeast Air Defense Sector

Timeline Tags: Complete 911 Timeline, 9/11 Timeline

Flight 175 passes from the airspace of the FAA’s Boston Center to the airspace of the New York Center, which is in Ronkonkoma, New York. [9/11 Commission, 8/26/2004, pp. 20 pdf file] New York Center air traffic controller Dave Bottiglia takes over monitoring the flight from Boston Center controller John Hartling (see (8:34 a.m.) September 11, 2001). Flight 175 waits nearly 45 seconds to check in with Bottiglia. According to author Lynn Spencer, this is “rather long, and Bottiglia is just about to call the plane.” But then Captain Victor Saracini, the pilot of Flight 175, makes radio contact, saying, “New York, United 175 heavy.” [Gregor, 12/21/2001 pdf file; Spencer, 2008, pp. 36]

Entity Tags: Dave Bottiglia, New York Air Route Traffic Control Center, Victor Saracini

Timeline Tags: Complete 911 Timeline, 9/11 Timeline

Victor Saracini.Victor Saracini. [Source: Family photo]Just after Flight 175 enters the airspace of the FAA’s New York Center (see 8:40 a.m. September 11, 2001), its pilot reports to the air traffic controller now managing the flight a suspicious transmission he had heard on departing Boston’s Logan Airport. The pilot, Captain Victor Saracini, tells the controller, Dave Bottiglia: “We figured we’d wait to go to your center. Ah, we heard a suspicious transmission on our departure out of Boston, ah, with someone, ah, it sounded like someone keyed the mikes and said, ah, ‘Everyone, ah, stay in your seats.’” [New York Times, 10/16/2001; 9/11 Commission, 7/24/2004, pp. 21; Spencer, 2008, pp. 36] Saracini is presumably referring to one of the three radio transmissions from Flight 11, where the voice of a hijacker could be heard (see 8:24 a.m. September 11, 2001 and (8:34 a.m.) September 11, 2001). However, none of these had included the hijacker telling people to stay in their seats, as Saracini describes, although the second and third transmissions included the hijacker telling the passengers, “Nobody move.” [9/11 Commission, 7/24/2004, pp. 19] Bottiglia responds: “Oh, okay. I’ll pass that along.” Referring to the fact that this was the end of the transmission he heard, Saracini adds, “It cut out,” and then asks Bottiglia, “Did you copy that?” [Gregor, 12/21/2001 pdf file; Spencer, 2008, pp. 36-37] This is the last radio transmission from Flight 175. The 9/11 Commission will conclude that the plane is hijacked within the next four minutes (see (Between 8:42 a.m. and 8:46 a.m.) September 11, 2001). [9/11 Commission, 8/26/2004, pp. 20 pdf file] According to author Lynn Spencer, since controllers are only given information on a need-to-know basis, Bottiglia was unaware there were problems with Flight 11, which has not yet entered his airspace. He touches his computer screen to connect to the hotline for his sector controller, and then reports: “UAL 175 just came on my frequency and he said he heard a suspicious transmission when they were leaving Boston. ‘Everybody stay in your seats’—that’s what he heard… just to let you know.” [New York Times, 10/16/2001; Spencer, 2008, pp. 36-37]

Entity Tags: New York Air Route Traffic Control Center, Victor Saracini, Dave Bottiglia

Timeline Tags: Complete 911 Timeline, 9/11 Timeline

Dave Bottiglia.Dave Bottiglia. [Source: ABC News]After Flight 11 appears on his radar screen, Dave Bottiglia, an air traffic controller at the FAA’s New York Center, is informed that this aircraft is suspected of having been hijacked. Flight 175 entered Bottiglia’s airspace not long before this (see 8:40 a.m. September 11, 2001). [MSNBC, 9/11/2002; 9/11 Commission, 8/26/2004, pp. 20 pdf file] Its pilot has just told Bottiglia about the “suspicious transmission” (presumably from Flight 11) he heard while departing Boston airport (see 8:41 a.m.-8:42 a.m. September 11, 2001). [Gregor, 12/21/2001 pdf file] Seconds later, Flight 11 also enters the area Bottiglia is monitoring and its target appears on his radar screen. The controller sitting next to Bottiglia gets up and points to the radar blip. He says: “You see this target here? This is American 11. Boston Center thinks it’s a hijack.” Bottiglia will later recall that his initial thought about Flight 11, based on this information, is that the hijackers “were probably going to Cuba.” As its transponder has been turned off (see (Between 8:13 a.m. and 8:21 a.m.) September 11, 2001), he has no altitude information for Flight 11, but can tell from the radar scope that it appears to be descending. According to author Lynn Spencer: “Even without a transponder, controller radars calculate ground speed for all radar targets, and when a plane is descending, the ground speed decreases. The flight had been ‘grounding’ 600 knots, and now it has decreased to 320.” Bottiglia follows Flight 11’s target on his radar screen until it disappears over New York City. [MSNBC, 9/11/2002; Spencer, 2008, pp. 37] Because he is focused on Flight 11, Bottiglia will not notice when Flight 175’s transponder code changes at 8:47 (see 8:46 a.m.-8:47 a.m. September 11, 2001). [9/11 Commission, 7/24/2004, pp. 21; 9/11 Commission, 8/26/2004, pp. 21 pdf file] The New York Center was first notified of Flight 11’s hijacking at 8:25 a.m. (see 8:25 a.m. September 11, 2001), though this information was not passed on to Bottiglia. [Federal Aviation Administration, 9/17/2001 pdf file; Spencer, 2008, pp. 36-37]

Entity Tags: Dave Bottiglia, New York Air Route Traffic Control Center

Timeline Tags: Complete 911 Timeline, 9/11 Timeline

An air traffic controller at the FAA’s Boston Center suggests that Flight 11 is going to crash into the World Trade Center. [The Learning Channel, 8/20/2006] Flight 11 is heading southbound toward New York, descending at about 3,200 feet per minute. [National Transportation Safety Board, 2/19/2002 pdf file] John Hartling, a controller at the Boston Center who has been monitoring it (see (8:34 a.m.) September 11, 2001), will later recall, “One of my fellow controllers on the other side of the room, I heard him say, ‘That airplane’s gonna hit the World Trade Center.’” [The Learning Channel, 8/20/2006] Flight 11 will crash into the WTC at 8:46 a.m. (see 8:46 a.m. September 11, 2001). [National Transportation Safety Board, 2/19/2002 pdf file]

Entity Tags: John Hartling, Boston Air Route Traffic Control Center

Timeline Tags: Complete 911 Timeline

The hole caused by the Flight 11 crash.The hole caused by the Flight 11 crash. [Source: Reuters]Flight 11 slams into the WTC North Tower (Building 1). Hijackers Mohamed Atta Waleed Alshehri, Wail Alshehri, Abdulaziz Alomari, and Satam Al Suqami presumably are killed instantly, and many more in the tower will die over the next few hours. Seismic records pinpoint the crash at 26 seconds after 8:46 a.m. [CNN, 9/12/2001; New York Times, 9/12/2001; North American Aerospace Defense Command, 9/18/2001; USA Today, 12/20/2001; Federal Emergency Management Agency, 5/1/2002, pp. 1-10; New York Times, 5/26/2002; USA Today, 8/13/2002; Associated Press, 8/21/2002; Newsday, 9/10/2002] The NIST report states the crash time to be 8:46:30. [National Institute of Standards and Technology, 9/2005, pp. 19] The 9/11 Commission Report states the crash time to be 8:46:40. [9/11 Commission, 7/24/2004, pp. 7] Investigators believe the plane still has about 10,000 gallons of fuel (see 8:57 a.m. September 11, 2001). [New York Times, 5/26/2002] The plane strikes the 93rd through 99th floors in the 110-story building. No one above the crash line survives; approximately 1,360 people die. Below the crash line, approximately 72 die and more than 4,000 survive. Both towers are slightly less than half full at the time of the attack, with between 5,000 to 7,000 people in each tower. This number is lower than expected. Many office workers have not yet shown up to work, and tourists to the observation deck opening at 9:30 A.M. have yet to arrive. [USA Today, 12/20/2001; National Institute of Standards and Technology, 9/2005, pp. 20-22] The impact severs some columns on the north side of the North Tower. Each tower is designed as a “tube-in-tube” structure and the steel columns which support its weight are arranged around the perimeter and in the core. The plane, which weighs 283,600 lb and is traveling at an estimated speed of around 430 mph (see October 2002-October 2005), severs 35 of the building’s 236 perimeter columns and damages another two. The damage to the South Tower’s perimeter will be similar (see 9:03 a.m. September 11, 2001). [National Institute of Standards and Technology, 9/2005, pp. 5-9, 20, 22] The perimeter columns bear about half of the tower’s weight, so this damage reduces its ability to bear gravity loads by about 7.5 percent. [National Institute of Standards and Technology, 9/2005, pp. 6] The actual damage to the 47 core columns is not known, as there are no photographs or videos of it, but there will be much speculation about this after 9/11. It will be suggested that some parts of the aircraft may have damaged the core even after crashing through the exterior wall. According to the National Institute of Standards and Technology (NIST): “Moving at 500 mph, an engine broke any exterior column it hit. If the engine missed the floor slab, the majority of the engine core remained intact and had enough residual momentum to sever a core column upon direct impact.” [National Institute of Standards and Technology, 9/2005, pp. 107] According to NIST’s base case computer model, three of the core columns are severed and another ten suffer some damage. [National Institute of Standards & Technology, 9/2005, pp. 189 pdf file] If this is accurate, it means that the impact damage to the core reduces the Tower’s strength by another approximately 7.5 percent, meaning that the building loses about 15 percent of its strength in total. This damage will be cited after 9/11 by NIST and others researchers as an event contributing to the building’s collapse (see October 23, 2002 and October 19, 2004). In addition, some of the fireproofing on the steel columns and trusses may be dislodged. The original fireproofing on the fire floors was mostly Blazeshield DC/F, but some of the fireproofing on the flooring has recently been upgraded to Blazeshield II, which is about 20 percent denser and 20 percent more adhesive. [National Institute of Standards & Technology, 9/2005, pp. xxxvi, 83 pdf file] Photographs and videos of the towers will not show the state of fireproofing inside the buildings, but NIST will estimate the damage to it using a computer model. Its severe case model (see (October 2002-October 2005)) will predict that 43 of the 47 core columns are stripped of their fireproofing on one or more floors and that fireproofing is stripped from trusses covering 60,000 ft2 of floor area, the equivalent of about one and a half floors. NIST will say that the loss of fireproofing is a major cause of the collapse (see April 5, 2005), but only performs 15 tests on fireproofing samples (see October 26, 2005). [National Institute of Standards and Technology, 9/2005, pp. 23] According to NIST, more fireproofing is stripped from the South Tower (see 9:03 a.m. September 11, 2001).

Entity Tags: Mohamed Atta, National Institute of Standards and Technology, Satam Al Suqami, Waleed Alshehri, Abdulaziz Alomari, World Trade Center, Wail Alshehri

Timeline Tags: Complete 911 Timeline, 9/11 Timeline

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 pdf file]
'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. [Washington Post, 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]

Entity Tags: Dave Bottiglia, Curt Applegate, New York Air Route Traffic Control Center

Timeline Tags: Complete 911 Timeline, 9/11 Timeline

A typical F-15.A typical F-15. [Source: US Air Force]Radar data will show that the two F-15s scrambled from Otis Air National Guard Base in Cape Cod, Massachusetts, are airborne by this time. [Washington Post, 9/15/2001; North American Aerospace Defense Command, 9/18/2001; 9/11 Commission, 7/24/2004, pp. 20] It is now eight minutes since the mission crew commander at NORAD’s Northeast Air Defense Sector (NEADS) ordered that the jets be launched (see 8:45 a.m. September 11, 2001). [Vanity Fair, 8/1/2006] It is 40 minutes since air traffic controllers had their last communication with Flight 11 (see 8:13 a.m. September 11, 2001), and 28 minutes since they became certain that the aircraft was hijacked (see (8:25 a.m.) September 11, 2001). Flight 11 crashed into the World Trade Center seven minutes ago (see 8:46 a.m. September 11, 2001). [9/11 Commission, 7/24/2004, pp. 7, 19 and 459]
Commander Wants Fighters Sent to New York - In Rome, New York, NEADS has just received news of the plane hitting the WTC (see 8:51 a.m. September 11, 2001). Major Kevin Nasypany, the facility’s mission crew commander, is asked what to do with the Otis fighters. He responds: “Send ‘em to New York City still. Continue! Go! This is what I got. Possible news that a 737 just hit the World Trade Center. This is a real-world.… Continue taking the fighters down to the New York City area, JFK [International Airport] area, if you can. Make sure that the FAA clears it—your route all the way through.… Let’s press with this.” [Vanity Fair, 8/1/2006] Yet there will be conflicting reports of the fighters’ destination (see (8:53 a.m.-9:05 a.m.) September 11, 2001), with some accounts saying they are directed toward military-controlled airspace off the Long Island coast. [Filson, 2003, pp. 56-59; 9/11 Commission, 6/17/2004]

Entity Tags: Northeast Air Defense Sector, Robert Marr, Kevin Nasypany, Otis Air National Guard Base

Timeline Tags: Complete 911 Timeline, 9/11 Timeline

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