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Context of '11:53 a.m. September 11, 2001: United Airlines Publicly Confirms that Flight 175 Has Crashed'

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Flight 175 hits the WTC South Tower. The picture was taken from a traffic helicopter.Flight 175 hits the WTC South Tower. The picture was taken from a traffic helicopter. [Source: WABC 7/ Salient Stills]Flight 175 hits the South Tower of the World Trade Center (Tower Two). Seismic records pinpoint the time at six seconds before 9:03 a.m. (rounded to 9:03 a.m.). Hijackers Marwan Alshehhi, Fayez Ahmed Banihammad, Mohand Alshehri, Hamza Alghamdi, and Ahmed Alghamdi presumably are killed instantly, and many more in the tower will die over the next few hours. [New York Times, 9/12/2001; CNN, 9/12/2001; CNN, 9/17/2001; 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; Associated Press, 8/21/2002; USA Today, 9/2/2002] According to the NIST report, the crash time is 9:02:59. [National Institute of Standards and Technology, 9/2005, pp. 38] According to the 9/11 Commission Report, the crash time is 9:03:11. [9/11 Commission, 7/24/2004, pp. 8] Millions watch the crash live on television. The plane strikes the 77th through 85th floors in the 110-story building. Approximately 100 people are killed or injured in the initial impact; 600 people in the tower eventually die. The death toll is far lower than in the North Tower because about two-thirds of the South Tower’s occupants have evacuated the building in the 17 minutes since the first tower was struck. [USA Today, 12/20/2001; National Institute of Standards and Technology, 9/2005, pp. 5-9, 41] The combined death toll from the two towers is estimated at 2,819, not including the hijackers. [Associated Press, 8/21/2002] The impact severs some columns on the south side of the South Tower. Each of the Twin Towers 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 is traveling at an estimated speed of around 500 mph (see October 2002-October 2005), severs 33 of the building’s 236 perimeter columns and damages another one. [National Institute of Standards and Technology, 9/2005, pp. 39] The perimeter columns bear about half of the tower’s weight, so the damage to them reduces the tower’s ability to bear gravity loads by about 7.1 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 be able to damage the core even after crashing through the exterior wall (see 8:46 a.m. September 11, 2001). [National Institute of Standards and Technology, 9/2005, pp. 107] According to NIST’s base case model, five of the core columns are severed and another five suffer some damage. [National Institute of Standards & Technology, 9/2005, pp. 235 pdf file] This may reduce the tower’s ability to bear loads by a further approximately 8 percent, meaning that the aircraft impact accounted for a loss of about 15 percent of the building’s strength. This damage will be cited as an event contributing to the building’s collapse after 9/11 (see October 23, 2002 and October 19, 2004). NIST’s base case estimate of damage to the North Tower’s core will be similar, even though the aircraft impact there was dissimilar (see 8:46 a.m. September 11, 2001). Flight 11 hit the North Tower’s core head on, whereas Flight 175 only hits the corner of the South Tower’s core. [National Institute of Standards and Technology, 9/2005, pp. 20-23, 38-41] In addition, some of the fireproofing on the steel columns and trusses may be dislodged (see 8:46 a.m. September 11, 2001). [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 the National Institute of Standards and Technology (NIST) will try to estimate the damage to fireproofing using a series of computer models. Its severe case model (see (October 2002-October 2005)) will predict that 39 of the 47 core columns are stripped of their fireproofing on one or more floors and that fireproofing is stripped from trusses covering 80,000 ft2 of floor area, the equivalent of about two 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. 41] According to NIST, less fireproofing is stripped from the North Tower (see 8:46 a.m. September 11, 2001).

Entity Tags: World Trade Center, Marwan Alshehhi, Fayez Ahmed Banihammad, Hamza Alghamdi, National Institute of Standards and Technology, Ahmed Alghamdi, Mohand Alshehri

Timeline Tags: Complete 911 Timeline, 9/11 Timeline

Within minutes of the second World Trade Center tower being hit, United Airlines tells the FAA’s Boston Center that Flight 175 is down. This is according to Colin Scoggins, a civilian manager who is the military liaison at the Boston Center. Scoggins will later recall, “When we phoned United [after the second tower was hit], they confirmed that United 175 was down, and I think they confirmed that within two or three minutes.” [Vanity Fair, 8/1/2006] However, according to the 9/11 Commission, even though by 9:20 United Airlines suspects that the second plane to hit the WTC was Flight 175 (see Between 9:10 a.m. and 9:20 a.m. September 11, 2001), at that time the identity of the crashed aircraft is “still unconfirmed.” It is not until 9:22 that United issues an advisory to its facilities, stating that Flight 175 has been in an accident in New York (see 9:22 a.m. September 11, 2001). [9/11 Commission, 8/26/2004, pp. 26 pdf file]

Entity Tags: Boston Air Route Traffic Control Center, Colin Scoggins, United Airlines

Timeline Tags: Complete 911 Timeline, 9/11 Timeline

Rich Miles, the manager of United Airlines’ System Operations Control center, located outside Chicago, issues an advisory to all United Airlines facilities, including the flight dispatchers. This advisory, which is issued under the name of UAL Chief Operating Officer Andy Studdert, states that Flight 175 has been involved in an accident in New York City, and that the airline’s crisis center has been activated. [Wall Street Journal, 10/15/2001; 9/11 Commission, 8/26/2004, pp. 26 pdf file] This appears to be United Airlines’ first proper confirmation that Flight 175 has crashed. However, it will not issue a press release confirming the crash until 11:53 a.m. (see 11:53 a.m. September 11, 2001). [United Airlines, 9/11/2001]

Entity Tags: Rich Miles, United Airlines, Andrew P. Studdert

Timeline Tags: Complete 911 Timeline, 9/11 Timeline

United Airlines issues a press release confirming that Flight 93 has crashed. Flight 93 went down in Pennsylvania shortly after 10:00 a.m. (see (10:06 a.m.) September 11, 2001). The release states: “United Airlines has confirmed one of its flights has crashed near Pittsburgh, Pennsylvania. United Flight 93, a Boeing 757 aircraft, is the flight number involved. The flight originated in Newark and was bound for San Francisco.” The release adds, “United is deeply concerned about a further flight, United Flight 175, a Boeing 767, which was bound from Boston to Los Angeles.” [United Airlines, 9/11/2001] Although Flight 175 hit the World Trade Center at 9:03 (see 9:03 a.m. September 11, 2001), United Airlines will not publicly confirm it has crashed until 11:53 a.m. (see 11:53 a.m. September 11, 2001).

Entity Tags: United Airlines

Timeline Tags: Complete 911 Timeline, 9/11 Timeline

United Airlines finally issues a press release confirming that Flight 175 has crashed, nearly three hours after this aircraft hit the World Trade Center (see 9:03 a.m. September 11, 2001). The release states, “United Airlines has now confirmed that two of its aircraft have crashed.” These include “United Flight 175, a Boeing 767 aircraft, [that] departed from Boston at 7:58 a.m. local time, bound for Los Angeles, with 56 passengers onboard, two pilots and seven flight attendants.” [United Airlines, 9/11/2001] United Airlines previously issued a press release, at 11:17, confirming the crash of Flight 93 (see 11:17 a.m. September 11, 2001), but this had stated that the airline was, at that time, only “deeply concerned” about Flight 175. [United Airlines, 9/11/2001] However, at 9:22, the United Airlines System Operations Control manager had issued an advisory to all the airline’s facilities, stating that Flight 175 had been in an accident in New York (see 9:22 a.m. September 11, 2001). [9/11 Commission, 8/26/2004, pp. 26 pdf file] And Colin Scoggins, the military liaison at the FAA’s Boston Center, will later claim that United confirmed to the center that Flight 175 was down, “within two or three minutes” (see (9:06 a.m.) September 11, 2001). [Vanity Fair, 8/1/2006]

Entity Tags: United Airlines

Timeline Tags: Complete 911 Timeline, 9/11 Timeline

The Federal Aviation Administration (FAA) sends a fax to the White House Situation Room, giving positive identification of the four hijacked aircraft involved in the morning’s attacks. However, two of the four flight numbers it provides are wrong. [Draper, 2007, pp. 143] Yet, by late morning, American Airlines and United Airlines had already issued press releases confirming that the four planes that crashed were flights 11, 175, 77, and 93 (see 11:17 a.m. September 11, 2001, (11:18 a.m.) September 11, 2001, and 11:53 a.m. September 11, 2001). [Associated Press, 9/11/2001; United Airlines, 9/11/2001; United Airlines, 9/11/2001] Journalist and author Robert Draper will later comment that, while there is much heroism on September 11, the FAA’s erroneous fax is an example of how the day is also “marred by appalling haplessness.” [Draper, 2007, pp. 143]

Entity Tags: Federal Aviation Administration, White House

Timeline Tags: Complete 911 Timeline, 9/11 Timeline

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