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Context of 'September 14, 2001-April 2002: Engineers Study Flight 77 Crash, But Are Granted Only Limited Access to Crash Site'

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W. Gene Corley.W. Gene Corley. [Source: ASCE]The Federal Emergency Management Agency (FEMA) and its contractor, Greenhorne and O’Mara, Inc., from Greenbelt, Maryland, begin putting together a Building Performance Assessment Team (BPAT), to conduct a formal analysis of the World Trade Center collapses, and produce a report of its findings. FEMA routinely deploys such teams following disasters, like floods or hurricanes. The 23-member BPAT team set up at the WTC collapse site is assembled by the American Society of Civil Engineers (ASCE), and headed by Dr. W. Gene Corley of Construction Technologies Laboratories in Skokie, Illinois. Corley was previously the principal investigator for FEMA’s study of the Murrah Building, in Oklahoma City in 1995. [New Yorker, 11/12/2001] BPAT team members are based nationwide and have to communicate with each other mostly by phone, as they continue with their regular jobs. While some of them are being paid for their efforts, others are working on the investigation voluntarily. They are told not to speak with reporters, under threat of dismissal from the team, supposedly because of the delicacy of the subject with which they are dealing. The BPAT team receives $600,000 of funding from FEMA, plus approximately $500,000 in ASCE in-kind contributions. [New York Times, 12/25/2001; Associated Press, 1/14/2002; US Congress, 3/6/2002] The team will have great difficulty accessing the collapse site and evidence they want to see (see March 6, 2002). They will be unable to get FEMA to obtain such basic data as detailed blueprints of the WTC buildings. FEMA will also refuse to allow them to make appeals to the public for photos and videos of the towers that might aid their investigation. Bureaucratic restrictions will often prevent them from making forensic inspections at Ground Zero, interviewing witnesses, or getting important evidence, like recorded distress calls from people who were trapped in the towers. [Glanz and Lipton, 2004, pp. 330] The end product of their investigation is the FEMA World Trade Center Building Performance Study, released in May 2002 (see May 1, 2002).

Entity Tags: World Trade Center, W. Gene Corley, American Society of Civil Engineers, Federal Emergency Management Agency, Greenhorne and O’Mara, Inc.

Timeline Tags: Complete 911 Timeline, 9/11 Timeline

The American Society of Civil Engineers (ASCE) studies the crash of Flight 77 into the Pentagon and the building’s architectural response to the impact, blast, and subsequent fires. [American Society of Civil Engineers, 1/17/2003] The six-member Pentagon Building Performance Study team is headed by Lead Technical Director Paul F. Mlakar, and also includes Mete A. Sozen. Mlakar and Sozen had previously worked together on the Federal Emergency Management Agency (FEMA) investigation into the Oklahoma City bombing under W. Gene Corley, who is now assigned as FEMA/ASCE’s team leader for the World Trade Center investigation (see September 12, 2001). [Corley et al., 10/1997; Mlakar et al., 1/2003, pp. i pdf file] Some aspects of the Oklahoma City investigation were controversial. [Guardian, 5/5/2001] Sozen is also tasked with “project conception” for Purdue University’s computer simulation of the Pentagon attack, images from which are also used in the Performance Report, when it is issued later (see January 23, 2003). [Purdue University Department of Computer Science, 9/11/2002] The Building Performance Study team only inspects the Pentagon on two occasions. Team leader Mlakar is granted “limited access” to the site for a week from September 14-21, and on October 4, “controlled access” is granted to the full team, which meets with Corley and inspects the site “for approximately four hours.” All airplane debris has been removed by this time, as well as most of the loose debris from the impact and collapse. Along with interviews and technical information provided by the Pentagon Renovation Project, the photos and data gleaned on these visits are the basis of the team’s analysis of the building’s response to the impact of Flight 77. The study is completed in April 2002, though the report will not be released for another nine months. [Mlakar et al., 1/2003, pp. 1, 18 pdf file]

Entity Tags: American Society of Civil Engineers, Mete Sozen, Paul Mlakar, Purdue University, W. Gene Corley, Pentagon

Timeline Tags: Complete 911 Timeline, 9/11 Timeline

Dr. Abolhassan Astaneh-Asl examines steel from the World Trade Center.Dr. Abolhassan Astaneh-Asl examines steel from the World Trade Center. [Source: University of California, Berkeley]An engineer investigating the remains of the World Trade Center sees melted girders and other evidence that the towers experienced extreme temperatures on 9/11. Dr. Abolhassan Astaneh-Asl is a professor of civil and environmental engineering at the University of California, Berkeley. He specializes in studying structural damage done by earthquakes and terrorist bombings. [Chronicle of Higher Education, 12/7/2001; CBS News, 3/11/2002] He arrives in New York on September 19 to conduct a two-week scientific reconnaissance of the collapsed towers, hoping to gain an understanding of how they had come down. His project is one of eight financed by the National Science Foundation to study the WTC disaster. [New York Times, 10/2/2001; Berkeleyan, 10/3/2001; US Congress. House. Committee on Science, 3/6/2002] He examines numerous pieces of steel taken from Ground Zero. [Chronicle of Higher Education, 12/7/2001] Astaneh-Asl will describe the WTC as “the best-designed building I have ever seen.” [San Francisco Chronicle, 10/22/2001] Yet he notices unusual warping and other damage in its remaining steel:
bullet At a recycling center in New Jersey, he sees 10-ton steel beams from the towers that look “like giant sticks of twisted licorice.” [Chronicle of Higher Education, 12/7/2001] He shows the San Francisco Chronicle a “banana-shaped, rust-colored piece of steel” that has “twisted like toffee during the terrorist attack.” [San Francisco Chronicle, 10/22/2001]
bullet He later recalls, “I saw melting of girders in [the] World Trade Center.” [PBS, 5/10/2007]
bullet He notes that steel has bent at several connection points that had joined the floors of the WTC to the vertical columns. He describes the connections as being smoothly warped, saying, “If you remember the Salvador Dali paintings with the clocks that are kind of melted—it’s kind of like that.” He adds, “That could only happen if you get steel yellow hot or white hot—perhaps around 2,000 degrees.” [Chronicle of Higher Education, 12/7/2001]
bullet Astaneh-Asl says that steel flanges have been reduced “from an inch thick to paper thin.” [Berkeleyan, 10/3/2001]
bullet He finds a foot-long twisted shard of steel that is “like a piece of bread, but it was high-strength steel.” He comments, “I haven’t seen anything like this [before].” [Berkeley Daily Planet, 10/20/2001]
bullet He finds “severely scorched [steel] members from 40 or so floors below the points of impact [by the planes].” He believes this is the result of the planes having destroyed the elevator walls, thereby allowing burning jet fuel to pour down into the building, igniting fires hundreds of feet below the impact floors. [CBS News, 3/12/2002]
bullet He says that, in some places, the fireproofing used to protect the WTC steel has “melted into a glassy residue.” [New York Times, 10/2/2001]
bullet Astaneh-Asl sees a charred I-beam from WTC Building 7, which collapsed late in the afternoon of 9/11. “The beam, so named because its cross-section looks like a capital I, had clearly endured searing temperatures. Parts of the flat top of the I, once five-eighths of an inch thick, had vaporized.” [New York Times, 10/2/2001]
Other individuals will report seeing molten metal in the remains of the World Trade Center in the weeks and months after 9/11 (see September 12, 2001-February 2002), and data collected by NASA reveals dozens of “hot spots” (some over 1,300 degrees Fahrenheit) at Ground Zero (see September 16-23, 2001). But Thomas Eagar—an engineering professor at the Massachusetts Institute of Technology—later comments that the “temperature of the fire at the WTC [on 9/11] was not unusual, and it was most definitely not capable of melting steel.” [Eagar and Musso, 12/2001] Yet Astaneh-Asl will later put forward the “tentative” conclusion, “The collapse of the [Twin Towers] was most likely due to the intense fire initiated by the jet fuel of the planes and continued due to burning of the building contents.” [Astaneh-Asl, 11/30/2003 pdf file] Astaneh-Asl is a member of the team assembled by the American Society of Civil Engineers to investigate the World Trade Center site after 9/11 (see September 12, 2001), though he will resign from this because he disagrees with its decision to keep findings secret until the initial inquiry has been completed. [New York Times, 10/2/2001; Associated Press, 9/6/2002]

Entity Tags: World Trade Center, Thomas Eagar, Abolhassan Astaneh-Asl

Timeline Tags: Complete 911 Timeline, 9/11 Timeline

The House Committee on Science holds a hearing on the investigation into the collapse of the World Trade Center on 9/11. Witnesses from industry, academia, and government testify on the collapses and the subsequent efforts to find out how and why they occurred. The hearings charter points out several problems that have severely hampered investigations. It says, “Early confusion over who was in charge of the [WTC collapse] site and the lack of authority of investigators to impound pieces of steel for examination before they were recycled led to the loss of important pieces of evidence that were destroyed early during the search and rescue effort.… Some of the critical pieces of steel—including the suspension trusses from the top of the towers and the internal support columns—were gone before the first BPAT [Building Performance Assessment Team] team member ever reached the site” (see September 12-October 2001). Furthermore, “The building owners, designers and insurers, prevented independent researchers from gaining access—and delayed the BPAT team in gaining access—to pertinent building documents largely because of liability concerns.” Regarding the decision to rapidly recycle the WTC steel, US Representative Joseph Crowley (D-NY) says, “I do believe that conspiracy theorists are going to have a field day with this,” and says this loss of important physical evidence “is not only unfortunate, it is borderline criminal.” In his statement before the committee, Glenn Corbett, a science professor at John Jay College, claims that the “lack of significant amounts of steel for examination will make it difficult, if not impossible, to make a definitive statement as to the cause and chronology of the collapse.” He also complains, “[W]e are staffing the BPAT with part-time engineers and scientists on a shoestring budget.” [US Congress, 3/6/2002; Associated Press, 3/7/2002]

Entity Tags: World Trade Center, Glenn Corbett, House Committee on Science, Joseph Crowley

Timeline Tags: Complete 911 Timeline, 9/11 Timeline

The Pentagon “video.”  These are the first two of five stills of the Pentagon impact. The first one is labeled “plane,” which appears to be the black object above the post on the far right. The second one is labeled ”Âœimpact.” The three other stills depict a growing fireball.The Pentagon “video.” These are the first two of five stills of the Pentagon impact. The first one is labeled “plane,” which appears to be the black object above the post on the far right. The second one is labeled ”Âœimpact.” The three other stills depict a growing fireball. [Source: Public domain] (click image to enlarge)A series of photos surface purporting to show a plane crashing into the Pentagon on 9/11. It is not clear who released the photos, but the Pentagon asserts that they are authentic, and were taken by a Pentagon security camera. The release of these pictures comes within days of the publication of the book l’Effroyable Imposture that disputes the claim that Flight 77 hit the Pentagon (see Early March 2002). “Officials could not immediately explain why the date typed near the bottom of each photograph is September 12 and the time is written as 5:37 p.m.,” the book notes. [US department of Defense, 9/11/2001; Associated Press, 3/8/2002; Fox News, 3/8/2002] The whole video, together with another also taken by a Pentagon security camera, will be released in 2006 (see May 16, 2006).

Entity Tags: Pentagon

Timeline Tags: Complete 911 Timeline, 9/11 Timeline

FEMA’s World Trade Center Building Performance Study.FEMA’s World Trade Center Building Performance Study. [Source: FEMA]FEMA releases its report of the WTC collapses. It concludes, “[W]ith the information and time available, the sequence of events leading to the collapse of each tower could not be definitively determined.” On Building 7: “The specifics of the fires in WTC 7 and how they caused the building to collapse remain unknown at this time.” [Federal Emergency Management Agency, 5/1/2002]

Entity Tags: World Trade Center, Federal Emergency Management Agency

Timeline Tags: Complete 911 Timeline, 9/11 Timeline

Overview of aircraft’s trajectory inside the Pentagon showing the points of entry (top right) and “exit” (bottom left).Overview of aircraft’s trajectory inside the Pentagon showing the points of entry (top right) and “exit” (bottom left). [Source: pentagonresearch (.com)] (click image to enlarge)A report about shoring used in the Pentagon submitted to the University of Maryland makes reference to a hole created in a wall inside the Pentagon on 9/11, near the end of the path of damage caused by the aircraft that hit the building. However, the assessment gives no specific explanation for what exactly caused the hole. The hole was on the ground level in a brick wall of the C Ring (the third of five concentric rings that form the Pentagon), on the A-E Drive, a service roadway that runs round the building between its C and B rings. The report says, “a nine foot diameter exit hole was created in the wall of C ring and the remainder of the debris from the impact ended up in the […] A-E Drive.” [Titus, 5/3/2002, pp. 9 pdf file] Similarly, other reports do not offer any conclusive explanation for what caused the hole. The American Society of Civil Engineers’ Pentagon Building Performance Report, published in 2003 January 23, 2003, will show the hole’s location in several diagrams, but explain only that “there was a hole in the east wall of Ring C, emerging into A-E Drive, between column lines 5 and 7 in Wedge 2. The wall failure was approximately 310 ft from where the fuselage of the aircraft entered the west wall of the building.” [Mlakar et al., 1/2003, pp. 28 pdf file] The Arlington County After-Action Report, published in 2002, contains a photo of the exit hole with the note “the damage extended all the way through the inner wall of the C Ring, a distance of approximately 285 feet.” It offers no further explanation for what precisely caused the hole. [US Department of Health & Human Services, 7/2002, pp. A8] Various explanations of how the hole came about are advanced after 9/11 (see September 15, 2001 and After).

Timeline Tags: Complete 911 Timeline

Sixteen months after the attack occurred, the American Society of Civil Engineers (ASCE) releases its Pentagon Building Performance Report on the Pentagon’s architectural response to the impact, blast, and subsequent fires caused by the Flight 77 crash on 9/11. [American Society of Civil Engineers, 1/17/2003] The report, which was finished several months earlier (see September 14, 2001-April 2002), admits “the volume of information concerning the aircraft crash… is rather limited,” but the team is able to give some details of the impact. The report reproduces the five frames of security camera footage made public in 2002 that showed the strike on the Pentagon (see March 7, 2002), seeing in them the approaching aircraft with its top about 20 feet above ground before exploding against and into the building. [Mlakar et al., 1/2003, pp. 14 pdf file] The report notes the plane struck a construction generator and vent structure on the lawn and speculates “portions of the wings might have been separated from the fuselage before the aircraft struck the building.” [Mlakar et al., 1/2003, pp. 35-36 pdf file] The ASCE finds that the plane hit the northern edge of Wedge One of the building—its southwest corner—which had been recently renovated, and that the plane made a 90 foot hole in the outer wall, destroying most ground floor support columns there and the limestone and brick façade between and in front of them. Aircraft debris is then reported to have passed through the building’s three outer rings E, D, and C, following the plane’s trajectory, entering the unrenovated Wedge Two towards the end of the path of destruction. [Mlakar et al., 1/2003, pp. 39 pdf file] The report does not say what caused the much-debated hole in the wall of Ring C, which led on to an internal driveway in the middle of the building. However, in a section on the damage caused by the debris it notes, “There was a hole in the east wall of Ring C, emerging into AE drive,” and a photo of the C Ring hole is included in the report. [Mlakar et al., 1/2003, pp. 28 pdf file]

Entity Tags: American Society of Civil Engineers, Pentagon

Timeline Tags: Complete 911 Timeline, 9/11 Timeline


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