5. UNITED 175


5.1 FAA Awareness

United Airlines Flight 175, a Boeing 767 carrying 65 passengers en route from Boston’s Logan Airport to Los Angeles, took off from Logan Airport at 8:14, and made contact with the Boston Air Route Traffic Control Center at 8:19.[i] Five minutes later, the flight was cleared to a cruising altitude of 31,000 feet.[ii]

At 8:37, the Kingston sector controller asked the pilots of United 175, among other flights, to look for American 11.

083818 UA175 affirms AA11 at FL29 tape 20R.mp3

The controller then turned United 175 thirty degrees to the right away from American 11.[iii]

083942 UA175 vectored 30 right for traffic tape 20R.mp3

The controller explained to Commission staff that he turned United 175 and directed the flight to maintain an altitude of 31,000 feet because of the unpredictable behavior of American 11.[iv]

United 175 was then passed to the New York Air Traffic Control Center at Ronkonkoma, NY, reporting in at 8:40.[v] The controller acknowledged United 175, then, like the Boston Center controller, engaged US Air Flight 583 in a discussion about American 11, asking whether Boston Center had asked the pilot to locate American 11. The pilot of US Air 583 responded affirmatively and gave an estimation of 29,000 feet for the altitude of American 11. [vi] The controller noted that “it looks like they shut off their transponder that’s why the question about [where it is].” At this point, at approximately 8:42, the pilot of United 175 broke in with the following transmission:

084131 AA11 UA175 ZNY report of suspicious transmission Boston.mp3

The controller turned United 175 away from the aircraft (American 11) as a safety precaution. At this point, United 175 had entered New York Center’s airspace and unfortunately, the controller responsible for United 175 was the same controller assigned the job of tracking the hijacked American 11. At 8:47, nearly simultaneously with the impact of American 11 into the World Trade Center, United 175’s assigned transponder code changed from 1470 to 3020, and then again to 3321.[vii] These changes were not noticed, however, for several minutes, as the controller was focused on trying to determine the location of American 11, which had disappeared as a primary radar track. Indeed, New York Center was completely focused on the situation with American 11, as indicated in the following report given by New York Center on a teleconference that had been established between their center, Boston Center and the Command Center. (Note that this report was made at approximately 8:48, just minutes after the impact of American 11 into the North Tower, though that was not known by the individual at the time)

084826 This is New York Center.mp3

Delta Airlines Flight 1489 radioed in at 8:50 and advised the same controller there was “a lot of smoke in lower Manhattan” and the World Trade Center looked like it was on fire. [viii] The controller acknowledged the message at 8:51, and agreed to pass on any news, then noticed a change in the transponder reading from United 175. The controller asked United 175 to recycle its transponder to the proper code.[ix] There was no response.

085146 UA175 ZNY recycle transponder.mp3

At 8:52, the controller made repeated attempts to reach the crew of United 175. Still, there was no response.[x]

At 8:53, after several unsuccessful attempts to reach United 175, the controller contacted another peer to discuss the situation.

085323 UA175 ZNY report to Sup and code 3321.mp3

The controller explained to Commission staff that he became alarmed when he saw a change of altitude along with the change in the transponder frequency; prior to the change in altitude, he assumed that the change in transponder frequency was human or mechanical error.[xi] US Air Flight 583 then radioed in and said he was getting “reports over the radio of a commuter plane hitting the World Trade Center”.[xii] The controller spent the next several minutes handing off the other flights on his scope to other controllers and moving aircraft out of the way of the unidentified aircraft (believed to be United 175) as it moved southwest and then turned northeast toward New York City.[xiii]

085408 UA175 ZNY Controller works UA175 and AA11 issue.mp3

At approximately 8:55, the controller-in-charge notified the Operations Manager that she believed United 175 had also been hijacked.[xiv] During interviews with Commission staff, the Air Traffic Manager (ATM) for New York Center said he made more than one attempt to notify the FAA Eastern Region Offices that United 175 may be a hijacked aircraft but was told by a staffer there that the managers were discussing a hijacked aircraft (presumably American 11) and refused to be disturbed.[xv] At 8:58, the New York Center controller searching for United 175 told another New York controller “we might have a hijack over here, two of them.”[xvi]

085751 UA175 ZNY ID as UA175 complex traffic.mp3

Between 9:01 and 9:02, a manager from New York Center told the FAA Command Center, in Herndon, VA:

090113 Mulligan Bell escalating big time.mp3

The other situation New York Center referred to was United 175. The evidence suggests this conversation was the only notice received prior to the second crash by either FAA HQ or Command Center that there was a second hijack.

While the Command Center was told about this “other aircraft” at 9:01, New York Center contacted New York terminal approach control and asked for help in locating United 175.

090021 Hey Joe ZNY TRACON x1085 TMU.mp3

The controllers observed the plane in a rapid descent; the radar data terminated over lower Manhattan.[xvii] At 9:03:02, United 175 crashed into World Trade Center’s South Tower.[xviii]

090247 UA175 visual report into tower TRACON TMUDD.mp3

090423 UA175 ZNY 2d aircraft into WTC.mp3

As United 175 was about to strike the South Tower, in a conversation monitored by FAA Command Center, a manager from Boston Center confirmed what was said by the hijackers on board American 11 during the first radio transmission:

090234 AA11 Jones thought some planes as in plural line 5114.mp3

After the impact into the South Tower, Boston Center updated the FAA’s New England Region.

090322 AA11 Nother one just hit line 5114.mp3

Boston Center immediately advised the New England Region that it was going to stop all aircraft scheduled to depart from any airport within Boston Center.[xix]

0904 Boston stops all airplanes.mp3

At 9:05, Boston Center confirmed for both FAA Command Center and New England Region that the hijackers aboard American 11 said “we have planes.”[xx]

090608 AA11 Confirmed on tape we have planes line 5114.mp3

At exactly the same time that the “we have planes” was confirmed, both Boston Center and New York Center closed down their airspace.[xxi] The result of this action was that aircraft were not permitted to depart from, arrive at, or travel through those Centers’ airspace until further notice.[xxii]

090401 Ground stops Boston and New York.mp3

After the second WTC crash, the Boston Center Operations Manager feared there may be additional attacks. He asked a New England Regional security representative if warnings could be sent to airborne aircraft by the airlines via a text messaging system (ACARS).

090713 ATCSCC ACARS increase security internationals line 5114.mp3

Within minutes of the second impact at the World Trade Center, Boston Center’s Operations Manager instructed all air traffic controllers in his center to use the radio frequencies to inform all aircraft in Boston Center of the events unfolding in New York and to advise the aircraft to heighten cockpit security in light of those events.[xxiii] Here are several examples of the cautionary radio transmissions sent by ZBW to other aircraft:

090933 Cockpit security L2431 and ZBW 31R tape.mp3

091042 Cockpit security ZBW advises 3 more planes 31R tape.mp3

At approximately 9:15, another Boston Center Manager ask[ed] Command Center to relay the message to all FAA centers in the country to use heightened cockpit security:

091532 Boston cockpit security.mp3

Commission staff has found no evidence to suggest that Command Center mangers acted on Boston’s request to issue a nationwide alert to aircraft. One Command Center manager interviewed told Commission staff that the FAA mindset on 9/11 was such that they would never have relayed this message directly to all pilots. She said the FAA would pass situational awareness to the airline company representatives who, in turn, would determine if such action was necessary.[xxiv]

5.2 Military Notification and Response

The first indication that the NEADS air defenders had of the second hijacked aircraft, United 175, came in a phone call from New York Center at 9:03.

090230 NEADS notified of UA175.mp3

The ID Technicians were on the phone with Boston Center seeking further information on United 175 when they found out that the plane may have crashed.[xxv] Before retrieving the flight’s vital statistics for NEADS, Boston Center confirmed the second crash at the Trade Center.[xxvi] There had been no prior notification that the plane was hijacked, or, for that matter, missing.[xxvii] The fighters from Otis Air Force Base were south of Long Island at the time.[xxviii]

The Mission Crew Commander’s reaction to the second explosion at the World Trade Center was to reject the idea of holding the fighters in military air space away from Manhattan.

090727 Panta over Manhattan some kind of play DRM 1 CH 2.mp3

The FAA cleared the air space. Radar data show that at 9:13, when the Otis fighters were about 115 miles away from the city, the fighters exited their holding pattern and set a course direct for Manhattan. They arrived at 9:25 and established a combat air patrol (CAP) over the city.[xxix]

Because the Otis fighters had expended a great deal of fuel in flying first to military air space and then to New York, the battle commanders were concerned about refueling. As NEADS personnel looked for refueling tankers in the vicinity of New York, the Mission Crew Commander considered scrambling the Langley fighters to New York to provide back-up for the Otis fighters until the NEADS Battle Cab ordered “[b]attle stations only at Langley.”[xxx]

090830 Langley battle stations not scramble D1 CH 5.mp3

The alert fighters at Langley Air Force Base were ordered to battle stations at 9:09.

090925 Langley BS Norfolk tower.mp3

Col. Marr, the battle commander at NEADS, and General Arnold, the CONR Commander, both recall that the planes were held on battle stations, as opposed to scrambling, because they might be called upon to relieve the Otis fighters over New York City if a refueling tanker was not located, and also because of the general uncertainty of the situation in the sky.[xxxi] According to retired Col. William Scott at the Commission’s May 23, 2003 hearing, “At 9:09, Langley F-16s are directed to battle stations, just based on the general situation and the breaking news, and the general developing feeling about what’s going on.”[xxxii] NORAD had no indication that any other plane had been hijacked.

5.3 Commission Findings and Assessment

The most noteworthy aspect of the time sequence recounted above is a time that is not mentioned: 8:43. In the days immediately following 9/11, both NORAD and FAA identified 8:43 as the time at which NORAD was notified of the hijacking of United 175; this time was picked up by The Washington Post and other prominent media outlets, and widely disseminated in the public record. The tapes and transcripts, corroborated by witness interviews, show, however, that 8:43 could not have been the time of notification. The FAA controller did not notice the change in transponder signal from United 175 until 8:51; there is no way that FAA could have notified NORAD of the hijacking at 8:43 when it did not even realize there was a problem with the flight until eight minutes later.

The Commission has been unable to identify the source of the inaccurate 8:43 hijack notification time for United 175. Both FAA and NORAD, however, eventually dropped that notification time from their official version of events; neither can account for its original inclusion.[xxxiii]

The inclusion of an 8:43 notification time in the early press releases from FAA and NORAD muddied the public record by raising questions about whether the Otis fighters were vectored properly; a flight path into military air space is difficult to justify when there is a reported second hijacking and one aircraft has already crashed into the World Trade Center. The actual flight path taken by the fighters is defensible given the fact that the second hijacking was reported as it was concluding; the Mission Crew Commander wanted the fighters eventually over New York City, but in the absence of a second emergent event was willing to hold the fighters over military airspace until the FAA could clear a path.

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[i] In the timeline section of the FAA report, “Summary of Air Traffic Hijack Events September 11, 2001,” Sept. 17, 2001, at 8:14:00: “United 175 begins takeoff roll, runway 9, Boston Logan International Airport. All communications with BOS and with Boston Departure Control are routine and normal.” Also see “Full Transcript; Aircraft Accident; UAL175; New York, NY; September 11, 2001,” position 47R, at 8:19:24.

[ii] “Full Transcript; Aircraft Accident; UAL175; New York, NY; September 11, 2001,” position 47R, at 8:30:56: “FAA: United 175 maintain three one o and contact the Boston Center on one two five point five seven.”

[iii] “Full Transcript; Aircraft Accident; UAL175; New York, NY; September 11, 2001,” position 20R, at 8:38:24.

[iv] John Hartling interview (Sept. 22, 2003).

[v] “Full Transcript; Aircraft Accident; UAL175; New York, NY; September 11, 2001,” position R42, at 8:40:32.

[vi] “Full Transcript; Aircraft Accident; UAL175; New York, NY; September 11, 2001,” position R42, at 8:41:07.

[vii] In the timeline section of the FAA report, “Summary of Air Traffic Hijack Events September 11, 2001,” Sept. 17, 2001, “ZNY air traffic computers do not correlate either of these codes with United 175. Consequently, the secondary radar return (transponder) indicating aircraft speed, altitude, and flight information begins to coast and is no longer associated with the primary radar return. NOTE: The controller communicating with United 175 is also monitoring the flight track of AAL11. Based on coordination received from ZBW indicating a possible hijack, most of the controller’s attention is focused on AAL11.”

[viii] “Full Transcript; Aircraft Accident; UAL175; New York, NY; September 11, 2001,” position R42, at 8:50:13.

[ix] “Full Transcript; Aircraft Accident; UAL175; New York, NY; September 11, 2001,” position R42, at 8:51:43: “United 175 recycle your transponder and squawk code 1470.”

[x] “Full Transcript; Aircraft Accident; UAL175; New York, NY; September 11, 2001,” position R42, at 8:52.

[xi] David Bottiglia interview (Oct. 1, 2003).

[xii] “Full Transcript; Aircraft Accident; UAL175; New York, NY; September 11, 2001,” position R42, at 8:54:07.

[xiii] “Full Transcript; Aircraft Accident; UAL175; New York, NY; September 11, 2001,” position R42, communications occur between approximately 8:54 and 9:04. At 8:57, the following exchange between controllers occurred: “I got some handoffs for you. We got some incidents going over here. Is Delta 2433 going to be okay at thirty-three? I had to climb him for traffic. I let you United 175 just took off out of uh thing we might have a hijack over here. Two of them.” “Full Transcript; Aircraft Accident; United 175; New York, NY; September 11, 2001,” position R42, at 8:57:52.

[xiv] FAA report, “Summary of Air Traffic Hijack Events September 11, 2001,” Sept. 17, 2001; Evanna Dowis interview (Sept. 30, 2004).

[xv] Michael McCormick interview (December 15, 2003); FAA record, Personnel Statement of Michael McCormick, Oct. 17, 2001.

[xvi] FAA Letterhead, “Full Transcript; Aircraft Accident; UAL175; New York, NY; September 11, 2001,” position R42, at 8:57:52.

[xvii] See timeline section of FAA report, “Summary of Air Traffic Hijack Events September 11, 2001,” Sept. 17, 2001: “0900:00 [] This time is approximate based on personnel statements from New York Terminal Radar Approach control (N90). N90 controller stated ‘at approximately 9:00 [], I observed an unknown aircraft south of the Newark, New Jersey Airport, northeast bound and descending out of twelve thousand nine hundred feet in a rapid rate of descent, the radar target terminated at the World Trade Center.”

[xviii] Note: William A. Scott testified that the time of impact was 9:02. William. A. Scott testimony (May 22, 2003).

[xix] FAA audio file, Herndon Command Center position 14, Line 5114, at 9:03.

[xx] FAA audio file, Herndon Command Center position 15, Line 5115, at 9:05

[xxi] FAA record, New York Center daily record of facility operations, p. 1.

[xxii] Michael McCormick interviews (October 1, 2003 and Dec. 15, 2003).

[xxiii] Terry Biggio interview (Sept. 22, 2003); FAA audio file, Herndon Command Center position 15, Line 5115, at 9:05 to 9:07.

[xxiv] Ellen King interview (April 5, 2004).

[xxv] NEADS audio file, Identification Technician position , channel 4, at 9:05:51.

[xxvi] NEADS audio file, Identification Technician position , channel 7, at 9:03:48.

[xxvii] Joseph McCain interview (Oct. 28, 2003); Robert Marr interview (Oct. 27, 2003 and Jan. 23, 2004); James Fox interview (Oct. 27, 2003); Dawne Deskins interview (Oct. 30, 2003).

[xxviii] Daniel S. Nash interview (Oct. 14, 2003); Timothy Duffy interview (Jan. 7, 2004).

[xxix] Daniel S. Nash interview (Oct. 14, 2003); Timothy Duffy interview (Jan. 7, 2004).

[xxx] NEADS audio file, Mission Crew Commander position, Channel 2, at 9:08:36.

[xxxi] Robert Marr interview (Oct. 27, 2003); Larry Arnold interview (Feb. 3, 2004); Robert Marr, quoted in Air War Over America, by Leslie Filson, p. 60: “The plan was to protect New York City.”

[xxxii] William A. Scott testimony (May 23, 2003).

[xxxiii] NORAD has taken the position that the error in time is accounted for by a twenty-minute mis-synchronization that occurred when the original tapes were reformatted and digitized. Because this reformatting did not occur until late 2003, however, it cannot account for the agencies’ misidentification of the time in the days immediately following 9/11.