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Complete 911 Timeline

World Trade Center Investigation

Project: Complete 911 Timeline
Open-Content project managed by matt, Derek, Paul, KJF, mtuck, paxvector

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At a press conference, President Bush discusses information gained from the interrogation of 9/11 mastermind reveals Khalid Shaikh Mohammed (KSM). In an apparent reference to the 9/11 attacks, Bush says that KSM “described the design of plane attacks on buildings inside the US and how operatives were directed to carry them out.… He told us the operatives had been instructed to ensure that the explosives went off at a point that was high enough to prevent people trapped above from escaping.” [New York Times, 9/15/2006] It is not clear if Bush really meant to say explosives or if this was a verbal slip-up.

Entity Tags: Khalid Shaikh Mohammed, George W. Bush

Timeline Tags: 9/11 Timeline

Category Tags: Khalid Shaikh Mohammed, WTC Investigation

In a reply to criticisms of its World Trade Center investigation, the National Institute of Standards and Technology (NIST) admits that it is unable to fully explain the total collapse of the Twin Towers on 9/11. NIST’s letter is a response to a “request for correction” letter sent to it five months earlier by Bob McIlvaine and Bill Doyle, who both lost family members on 9/11, along with scientists Kevin Ryan and Steven E. Jones, architect Richard Gage, and the group Scholars for 9/11 Truth and Justice. This letter made several assertions about NIST’s final reports of its WTC investigation, and suggested they had violated the Data Quality Act and NIST’s information quality standards. NIST’s reply denies the requests for corrections. However, it also mentions, “[W]e are unable to provide a full explanation of the total collapse” of the World Trade Center. [National Institute of Standards and Technology, 9/27/2007 pdf file] In its final report on the Twin Towers collapses, released in October 2005, NIST admitted that its investigation did “not actually include the structural behavior of the tower after the conditions for collapse initiation were reached and collapse became inevitable” (see October 26, 2005). [National Institute of Standards and Technology, 9/2005, pp. 82]

Entity Tags: National Institute of Standards and Technology, World Trade Center

Timeline Tags: 9/11 Timeline

Category Tags: WTC Investigation, 9/11 Investigations

The National Institute of Standards and Technology (NIST) publishes a fact sheet responding to 14 “frequently asked questions” about its investigation into the collapse of the Twin Towers on September 11. Some of the key questions and answers are as follows:
bullet Regarding the question, “Why was the collapse of WTC 1 and 2 not arrested by the intact structure below the floors where columns first began to buckle?” NIST replies, “The vertical capacity of the connections supporting an intact floor below the level of collapse was adequate to carry the load of 11 additional floors if the load was applied gradually and 6 additional floors if the load was applied suddenly (as was the case).” As the number of floors above the points where the collapses initiated exceeded six (12 in the case of the North Tower, 29 for the South), NIST says, “[T]he floors below the level of collapse initiation were unable to resist the suddenly applied gravitational load from the upper floors of the buildings.”
bullet In answer to the question of “Why was physical evidence not collected immediately following the collapse of the WTC towers,” NIST says, “In the initial days and weeks following the WTC disaster, the emphasis was on rescue and later on recovery, necessitating the removal of steel and disturbing the collapse site.” It adds, “NIST did not receive the legal authority to collect and preserve physical evidence from a disaster/failure site until the National Construction Safety Team Act became law in October 2002.” The decision to rapidly scrap the remaining steel from the WTC was made shortly after 9/11 (see Shortly After September 11, 2001), but the destruction of this steel was strongly protested by some within the engineering and firefighting communities (see December 25, 2001 and January 4, 2002).
bullet In response to a question about why it did not use its subpoena authority during its investigation, NIST states that its “experience during the investigation was that it was able to obtain all essential documentary and visual evidence without the need to invoke subpoena authority.”
bullet In answer to the question, “Why didn’t NIST fully model the collapse initiation and propagation of WTC towers?” NIST says, “Once the collapse had begun, the propagation of the collapse was readily explained without the same complexity of modeling” as was used to determine the sequence of events leading up to the collapse initiation.
bullet During its investigation, NIST had selected several variables for its computer simulations, and then experimented with different possible values (see (October 2002-October 2005)). But it has been asked: “Why didn’t NIST consider the ‘base’ and ‘less severe’ cases throughout its analysis of the WTC towers? What was the technical basis for selecting only the ‘more severe’ case for its analyses?” Its answer is that, “Of the three [possible values], the more severe case resulted in the closest agreement with the visual and physical evidence.” [National Institute of Standards and Technology, 12/14/2007]
NIST published its final report on the Twin Towers collapse in October 2005 (see October 26, 2005). It released an earlier fact sheet answering previous “frequently asked questions” in August 2006 (see August 30, 2006). [National Institute of Standards and Technology, 8/30/2006]

Entity Tags: National Institute of Standards and Technology

Timeline Tags: 9/11 Timeline

Category Tags: WTC Investigation, 9/11 Investigations

For the first time, a scientific journal publishes a letter by scientists who think the World Trade Center buildings were destroyed by explosives, rather than impact damage and fire. The letter, cautiously entitled “Fourteen Points of Agreement with Official Government Reports on the World Trade Center Destruction,” is published in the Open Civil Engineering Journal. The lead author is Steven E. Jones, a physicist formerly at Brigham Young University. The abstract says: “Reports by FEMA and NIST lay out the official account of the destruction of the World Trade Center on 9/11/2001. In this Letter, we wish to set a foundation for productive discussion and understanding by focusing on those areas where we find common ground with FEMA and NIST, while at the same time countering several popular myths about the WTC collapses.” [Open Civil Engineering Journal, 4/8/2008; Deseret News, 5/3/2008] However, unlike the vast majority of journals, the Open Civil Engineering Journal charges authors to publish their articles or letters in it. [Open Civil Engineering Journal, 2007]

Entity Tags: National Institute of Standards and Technology, Steven E. Jones, Federal Emergency Management Agency

Category Tags: WTC Investigation, 9/11 Investigations

Explosives on a chipExplosives on a chip [Source: Gary Meek/Georgia Institute of Technology]According to an article published in The Environmentalist, a peer-reviewed scientific journal published by Springer Netherlands, air quality data collected by the Environmental Protection Agency (EPA) at Ground Zero support the hypothesis that cutting charges made with thermite were used to demolish the World Trade Center. The article by authors (and 9/11 truth activists) Kevin Ryan, James Gourley, and Steven Jones says the presence of thermite would best explain three major documented anomalies: [Ryan, Gourley, and Jones, 8/4/2008]
1) The Persistence of Fires at Ground Zero - As has been extensively reported, the rubble at Ground Zero continued to burn for months after 9/11, despite rain as well as firefighters’ use of large quantities of water and of the chemical fire suppressant Pyrocool. [New York Times, 11/19/2001] There is also eyewitness and photographic evidence of molten metal (see September 12, 2001-February 2002) and of explosions accompanied by white dust clouds. The book Aftermath: World Trade Center Archive by photographer Joel Meyerowitz shows a picture of such an explosion taking place on November 8, 2001. [Meyerowitz, 2006, pp. 178] Another photography books by NYPD officer John Botte also shows a picture of smoke emerging from the pile at Ground Zero and explains: “Occasionally, a huge flame would shoot out from the middle of the pile, sounding like a blow torch, as it did here.” [Botte, 2006, pp. 48-49]
2) Spikes of Certain Chemicals in the Air - EPA data shows that several spikes of chemical products of combustion, called volatile organic chemicals (VOC), occurred in October and November 2001, and in February 2002. According to the authors, these spikes indicate “abrupt, violent fires.”
3) The Presence of 1,3-Diphenylpropane - A third anomaly was the presence of large quantities of 1,3-diphenylpropane (1,3-DPP) in the air, a chemical that had not been found in previous structure fires. An EPA scientist told Newsday, “We’ve never observed it in any sampling we’ve ever done.” [Newsday, 9/14/2003]
A possible explanation would be the presence of novel “energetic nanocomposites” which include 1,3-DPP, according to scientific articles reviewed by Ryan et al. Such materials are “amenable to spray-on applications.” A 2002 report said: “The energetic coating dries to give a nice adherent film. Preliminary experiments indicate that films of the hybrid material are self-propagating when ignited by thermal stimulus.” [Ryan, Gourley, and Jones, 8/4/2008] The main center for nanocomposites research is Lawrence Livermore National Laboratory (LLNL). An October 2000 article in a LLNL publication provided an introduction to the research conducted there: “Energetic nanocomposites have a fuel component and an oxidizer component mixed together. […] In one such material (termed a thermite pyrotechnic), iron oxide gel reacts with metallic aluminum particles to release an enormous amount of heat. ‘These reactions typically produce temperatures in excess of 3,500 degrees Celsius’ says [LLNL researcher Randy] Simpson.” [Science & Technology Review, 10/2000] The authors conclude that “[t]he presence of energetic materials, specifically energetic nanocomposites, at [Ground Zero], has the potential to explain much of the unusual environmental data seen at the WTC. Thermite […] is such a pyrotechnic mixture that cannot be easily extinguished and is a common component of energetic nanocomposites.… [T]he detection of 1,3-DPP at the WTC supports this hypothesis. Finally, the spikes in VOCs, detected by EPA on specific dates, are more readily explained as a result of short-lived, violent fires caused by energetic materials.” [Ryan, Gourley, and Jones, 8/4/2008]

Entity Tags: Steven E. Jones, James R. Gourley, Environmental Protection Agency, Kevin Ryan

Category Tags: WTC Investigation, 9/11 Investigations

After the National Institute of Standards and Technology (NIST) announces the results of its investigation into the collapse of World Trade Center Building 7, some critics dispute its explanation for the collapse and question its apparent debunking of claims that explosives were used to demolish the building. The 47-story tower collapsed late in the afternoon of 9/11, even though no plane hit it (see (5:20 p.m.) September 11, 2001). Some have argued that fire and the falling debris from the Twin Towers’ collapses should not have brought down such a large steel and concrete structure. [Associated Press, 8/21/2008]
NIST Lacks 'the Expertise on Explosives' - James Quintiere, a professor of fire protection engineering at the University of Maryland who previously worked as the chief of NIST’s fire science and engineering division, says that NIST does not “have the expertise on explosives, so I don’t know how they came to that conclusion,” that explosives did not cause the collapse. However, Quintiere says he never personally believed explosives were involved. [Los Angeles Times, 8/22/2008] Richard Gage, a California architect and leader of a group called Architects and Engineers for 9/11 Truth, complains, “How much longer do we have to endure the cover-up of how Building 7 was destroyed?” The New York Times points out that “the collapse of 7 World Trade Center—home at the time to branch offices of the Central Intelligence Agency, the Secret Service, and the Giuliani administration’s emergency operations center—is cited in hundreds of Web sites and books as perhaps the most compelling evidence that an insider secretly planted explosives, intentionally destroying the tower.” [New York Times, 8/21/2008]
NIST Presentation - At a presentation of its findings earlier in the day, NIST announced that, in its three-year study of the collapse, it found no evidence showing explosives were used to bring the building down. [National Institute of Standards and Technology, 8/21/2008; National Institute of Standards and Technology, 8/21/2008] During his summary of the findings of NIST’s WTC 7 investigation (see August 21, 2008), lead investigator Shyam Sunder said, “We did not find any evidence that explosives were used to bring the building down.” [National Institute of Standards and Technology, 8/21/2008]
'No Witness Reports' of Loud Explosions - In the draft version of its final report on the collapse, which is released on this day (see August 21, 2008), NIST explains: “Blast from the smallest charge capable of failing a critical column… would have resulted in a sound level of 130 dB to 140 dB at a distance of at least half a mile if unobstructed by surrounding buildings.… This sound level is consistent with standing next to a jet plane engine and more than ten times louder than being in front of the speakers at a rock concert. There were no witness reports of such a loud noise, nor was such a noise heard on the audio tracks of video recordings of the WTC 7 collapse.” [National Institute of Standards and Technology, 8/2008, pp. 44-45 pdf file]
NIST Rules out Thermite - Skeptics have argued that an incendiary material called thermite was used to bring down WTC 7 (see August 4, 2008), and this would not necessarily have created such a loud explosive boom. [New York Times, 8/21/2008] But in a fact sheet published on this day, NIST responds: “To apply thermite to a large steel column, approximately 0.13 lb of thermite would be needed to heat and melt each pound of steel. For a steel column that weighs approximately 1,000 lbs. per foot, at least 100 lbs. of thermite would need to be placed around the column, ignited, and remain in contact with the vertical steel surface as the thermite reaction took place. This is for one column… presumably, more than one column would have been prepared with thermite, if this approach were to be used. It is unlikely that 100 lbs. of thermite, or more, could have been carried into WTC 7 and placed around columns without being detected, either prior to Sept. 11 or during that day.” [National Institute of Standards and Technology, 8/21/2008] Sunder says that investigators therefore decided not to use their computer model to evaluate whether a thermite-fueled fire might have brought down WTC 7. Pointing to the omission, one skeptic says, “It is very difficult to find what you are not looking for.” [New York Times, 8/21/2008] In a 2006 fact sheet, NIST in fact admitted it “did not test for the residue” of explosives or thermite in the remaining structural steel from the WTC collapses (see August 30, 2006). [National Institute of Standards and Technology, 8/30/2006] And, as the New York Times notes, “Adding to the suspicion is the fact that in the rush to clean up the site, almost all of the steel remains of the tower were disposed of, leaving investigators in later years with little forensic evidence” (see Shortly After September 11, 2001 and September 12-October 2001). [New York Times, 8/21/2008]
Extensive Preparations for Demolition - NIST’s new fact sheet also points out: “For [WTC 7] to have been prepared for intentional demolition, walls and/or column enclosures and fireproofing would have to be removed and replaced without being detected. Preparing a column includes steps such as cutting sections with torches, which produces noxious and odorous fumes. Intentional demolition usually requires applying explosive charges to most, if not all, interior columns, not just one or a limited set of columns in a building.” [National Institute of Standards and Technology, 8/21/2008]

Entity Tags: Richard Gage, National Institute of Standards and Technology, Shyam Sunder, World Trade Center, James Quintiere

Timeline Tags: 9/11 Timeline

Category Tags: WTC Investigation, 9/11 Investigations

The National Institute of Standards and Technology (NIST) releases a draft version of the final report of its investigation of the collapse of World Trade Center Building 7, the 47-story skyscraper which collapsed late in the afternoon of 9/11 (see (5:20 p.m.) September 11, 2001). [National Institute of Standards and Technology, 8/21/2008] The report describes NIST’s conclusions on how fires that followed the impact of debris from the north WTC tower’s collapse resulted in the eventual collapse of WTC 7. It evaluates the emergency response and building evacuation procedures, and provides 13 recommendations for construction of buildings in the future, and improved procedures and practices. [National Institute of Standards and Technology, 8/2008, pp. xiii pdf file] Some of the report’s key findings are:
bullet NIST describes its theory of what caused WTC 7 to collapse: “The probable collapse sequence… was initiated by the buckling of a critical interior column.… This column had become unsupported over nine stories after initial local fire-induced damage led to a cascade of local floor failures. The buckling of this column led to a vertical progression of floor failures up to the roof and to the buckling of adjacent interior columns to the south of the critical column. An east-to-west horizontal progression of interior column buckling followed, due to loss of lateral support to adjacent columns, forces exerted by falling debris, and load redistribution from other buckled columns. The exterior columns then buckled as the failed building core moved downward, redistributing its loads to the exterior columns. Global collapse occurred as the entire building above the buckled region moved downward as a single unit.” [National Institute of Standards and Technology, 8/2008, pp. xxxii pdf file]
bullet The collapse of WTC 7 “represents the first known instance of the total collapse of a tall building primarily due to fires. The collapse could not have been prevented without controlling the fires before most of the combustible building contents were consumed.” [National Institute of Standards and Technology, 8/2008, pp. 43 pdf file]
bullet The fires in WTC 7 “were ignited as a result of the impact of debris from the collapse of WTC 1, which was approximately 370 ft to the south.… The fires were ignited on at least 10 floors; however, only the fires on floors 7 through 9 and 11 through 13 grew and lasted until the time of the building collapse.” [National Institute of Standards and Technology, 8/2008, pp. xxxi-xxxii pdf file]
bullet “Even without the initial structural damage caused by debris impact from the collapse of WTC 1, WTC 7 would have collapsed from fires having the same characteristics as those experienced on September 11, 2001.” [National Institute of Standards and Technology, 8/2008, pp. 44 pdf file]
bullet “Had a water supply for the automatic sprinkler system been available and had the sprinkler system operated as designed, it is likely that fires in WTC 7 would have been controlled and the collapse prevented.” [National Institute of Standards and Technology, 8/2008, pp. 43 pdf file]
bullet Other skyscrapers had previously survived comparable fires. “The fires in WTC 7 were similar to those that have occurred previously in several tall buildings (One New York Plaza, 1970, First Interstate Bank, 1988, and One Meridian Plaza, 1991) where the automatic sprinklers did not function or were not present. However, because of differences between their structural designs and that of WTC 7, these three buildings did not collapse.” [National Institute of Standards and Technology, 8/2008, pp. 43 pdf file]
bullet NIST found that “temperatures did not exceed 300°C in the core or perimeter columns in WTC 7,” including the three interior columns that NIST says were the first to buckle in the collapse. “None of these columns were significantly weakened by elevated temperatures.” [National Institute of Standards and Technology, 8/2008, pp. 49-50 pdf file]
bullet NIST says it found “no evidence to suggest that WTC 7 was not designed in a manner generally consistent with applicable building codes and standards.” [National Institute of Standards and Technology, 8/2008, pp. 53 pdf file]
bullet The report concludes that neither explosives nor fuel oil fires fed by diesel tanks in WTC 7 played any role in the collapse (see August 21, 2008 and August 21, 2008). [National Institute of Standards and Technology, 8/2008, pp. 44-45 pdf file]
bullet However, the report points out that WTC 7 “and the records kept within it were destroyed, and the remains of all the WTC buildings were disposed of before congressional action and funding was available for this investigation to begin. As a result, there are some facts that could not be discerned, and thus there are uncertainties in this accounting. Nonetheless, NIST was able to gather sufficient evidence and documentation to conduct a full investigation upon which to reach firm findings and recommendations.” [National Institute of Standards and Technology, 8/2008, pp. xxxi pdf file]
NIST released a progress report in June 2004, which had included its “working hypothesis” at that time for the collapse of WTC 7 (see June 18, 2004). [National Institute of Standards and Technology, 6/18/2004] After suggestions are made by members of the public in response to the current draft report, NIST will release the finished version of the report in November 2008, which includes the same major findings and recommendations as the draft version (see November 20, 2008). [National Institute of Standards and Technology, 11/20/2008]

Entity Tags: World Trade Center, National Institute of Standards and Technology

Timeline Tags: 9/11 Timeline

Category Tags: WTC Investigation, 9/11 Investigations

The National Institute of Standards and Technology (NIST) publicly rejects the theory that diesel fuel tanks installed in World Trade Center Building 7 played any role in the 47-story tower’s collapse, late in the afternoon of 9/11. This is clearly set out in a question-and-answer factsheet published on this day, together with an announcement of NIST’s draft report on the building’s collapse (see August 21, 2008 and August 21, 2008). The factsheet asks, “Did fuel oil systems in WTC 7 contribute to its collapse?” The answer is “No…. The worst-case scenarios associated with fires… could not have been sustained long enough, could not have generated sufficient heat to weaken critical interior columns, and/or would have produced large amounts of visible smoke from the lower floors, which were not observed.” [National Institute of Standards and Technology, 8/21/2008; New York Times, 8/21/2008] These findings are echoed in the draft version of its final report on the collapse. [National Institute of Standards and Technology, 8/2008, pp. xxxii pdf file] WTC 7 had three emergency power systems, all of which ran on diesel fuel. The systems contained two 12,000 gallon fuel tanks and two 6,000 gallon tanks located beneath the building’s loading docks, and another 6,000 gallon tank on its first floor. There were also 275 gallon tanks on the fifth, seventh, and eighth floors, and a 50 gallon tank on the ninth floor. [National Institute of Standards and Technology, 8/21/2008] It has previously been suggested that diesel stored in these tanks might have contributed to fires that led to WTC 7’s collapse (see March 2, 2002). [New York Times, 3/2/2002] This possibility was proposed in the final report of the Federal Emergency Management Agency (FEMA) investigation of the WTC collapses, published in May 2002 (see May 1, 2002). [Federal Emergency Management Agency, 5/1/2002, pp. 5-28 - 5-29] But in his summary of the findings of NIST’s three-year study of WTC 7, lead investigator Shyam Sunder says the building’s collapse was “not due to fires from the substantial amount of diesel fuel stored in the building.” [National Institute of Standards and Technology, 8/21/2008]

Entity Tags: World Trade Center, National Institute of Standards and Technology, Shyam Sunder

Timeline Tags: 9/11 Timeline

Category Tags: WTC Investigation, 9/11 Investigations

NIST lead investigator Shyam Sunder answering questions about NIST’s three-year study of the collapse of WTC 7.NIST lead investigator Shyam Sunder answering questions about NIST’s three-year study of the collapse of WTC 7. [Source: Don Berkemeyer / National Institute of Standards and Technology]The National Institute of Standards and Technology (NIST) announces the findings of its study of the collapse of World Trade Center Building 7, and says the 47-story tower fell late in the afternoon of 9/11 primarily due to fires. [National Institute of Standards and Technology, 8/21/2008; National Institute of Standards and Technology, 8/21/2008] NIST releases its findings as part of a 915-page report, which is the result of three years’ work by over 50 federal investigators and a dozen contractors (see August 21, 2008). [New York Times, 8/21/2008]
Collapse Is 'No Longer a Mystery' - In a news conference at NIST’s headquarters in Gaithersburg, Maryland, lead investigator Shyam Sunder admits: “[W]e knew from the beginning of our study that understanding what happened to Building 7 on 9/11 would be difficult. It did not fit any textbook description that you could readily point to and say, yes, that’s why the building failed.” But, he says, “[T]he reason for the collapse of World Trade Center 7 is no longer a mystery.” [National Institute of Standards and Technology, 8/21/2008; New York Times, 8/21/2008]
'New Phenomenon' Caused Collapse - Sunder says the “critical factor” that initiated the collapse was “thermal expansion of long-span floor systems located in the east side of the building,” and adds that NIST’s study “has identified thermal expansion as a new phenomenon that can cause structural collapse. For the first time we have shown that fire can induce a progressive collapse.”
Collapse Sequence - Sunder describes the sequence of events NIST believes led to the collapse of WTC 7. He says debris from the collapse of the north WTC tower “started fires on at least 10 floors of the building. The fires burned out of control on six of these 10 floors for about seven hours. The city water main had been cut by the collapse of the two WTC towers, so the sprinklers in Building 7 did not function for much of the bottom half of the building.” He continues: “Fires on floors 7 through 9 and 11 through 13 were particularly severe.… Eventually, a girder on floor 13 lost its connection to a critical interior column.” Floor 13 collapsed, beginning a cascade of floor failures down to the fifth floor. “With the support of these floors gone, column 79 buckled, which initiated the fire-induced progressive collapse of the building.… This in turn caused the failure of nearby columns 80 and 81 and floor failures up to the roof line.… As the roof line begins to fall adjacent columns buckle as well. In quick succession, the remaining interior columns failed from east to west across WTC 7, until the entire core began moving downward. Finally, the remaining outer shell or fa├žade of the building fell.”
NIST Created 'Virtual WTC 7' Model - Sunder says that NIST reached its conclusions about the collapse “by reconstructing the entire building, beam by beam, column by column, connection by connection into a computer model, a virtual WTC 7 building. We then filled that virtual building with as much detail as possible about exactly what types of furnishings were on each floor. Then we set fire to those virtual offices on the floors where video and other visual evidence told us the fires burned.” The investigators “used a well-validated computer program developed at NIST, for studying the growth and spread of fires, to calculate temperatures throughout the building.… And we used well-established data on the properties of structural steel, the sprayed fire resistive material or fireproofing, and other building materials to determine how those temperatures affected the structure.”
Explosives Not Used - Sunder says that the investigators “did not find any evidence that explosives were used to bring the building down” (see August 21, 2008), nor was the collapse “due to fires from the substantial amount of diesel fuel stored in the building” (see August 21, 2008). NIST commenced its investigation of the WTC collapses in 2002 (see August 21, 2002) and issued its findings on the collapses of the Twin Towers in October 2005 (see October 26, 2005). Since then it has been focused on WTC 7. [Government Computer News, 8/21/2008; National Institute of Standards and Technology, 8/21/2008]
Final Report to Be Released - After suggestions are made by members of the public in response to its current report, NIST will release a finished version of the same report in November 2008, thereby completing its WTC investigation (see November 20, 2008). [National Institute of Standards and Technology, 11/20/2008]

Entity Tags: World Trade Center, National Institute of Standards and Technology, Shyam Sunder

Timeline Tags: 9/11 Timeline

Category Tags: WTC Investigation, 9/11 Investigations

’Iron atoms in steel: Black balls show irregularities that disrupt magnetic fields, weakening steel.’’Iron atoms in steel: Black balls show irregularities that disrupt magnetic fields, weakening steel.’ [Source: BBC]Sergei Dudarev, a scientist with Britain’s Atomic Energy Agency, says that newly-discovered properties of steel could explain why the World Trade Center towers collapsed. Dr. Dudarev researches steel that can withstand the extreme temperatures inside a nuclear fusion reactor. He says that at about 500° Celsius, a temperature often reached in building fires, tiny irregularities in the structure of steel can cause a softening of the metal, although that is still far below the melting point. Dudarev says: “The steel didn’t melt, it just became soft. It is an unusual state and the temperatures in the Twin Towers were high enough to cause it because the thermal insulation was knocked off the girders through the impact with the aircraft.” [Guardian, 9/9/2008; BBC News, 9/10/2008; Independent, 9/10/2008; ABC Radio National (Australia), 9/20/2008]

Entity Tags: Sergei Dudarev

Category Tags: WTC Investigation, 9/11 Investigations

NIST’s ‘Final Report on the Collapse of World Trade Center Building 7.’NIST’s ‘Final Report on the Collapse of World Trade Center Building 7.’ [Source: National Institute of Standards and Technology.]The National Institute of Standards and Technology (NIST) releases the final report of its three-year investigation of the collapse of World Trade Center Building 7, the 47-story skyscraper which collapsed late in the afternoon of 9/11 (see (5:20 p.m.) September 11, 2001). This is the completed version of the report, and comes three months after a draft version was released for public comment (see August 21, 2008). NIST states that the new report “is strengthened by clarifications and supplemental text suggested by organizations and individuals worldwide in response to the draft WTC 7 report.” NIST conducted an additional computer analysis in response to comments from the building community, and made several minor amendments to the report. But, it says, “the revisions did not alter the investigation team’s major findings and recommendations, which include identification of fire as the primary cause for the building’s failure.” With the release of this report, NIST has completed its six-year investigation of the World Trade Center collapses, which it commenced in August 2002 (see August 21, 2002). The final report of its investigation of the Twin Towers’ collapses was published in October 2005 (see October 26, 2005). [National Institute of Standards and Technology, 11/20/2008; Occupational Health and Safety, 11/25/2008]

Entity Tags: World Trade Center, National Institute of Standards and Technology

Timeline Tags: 9/11 Timeline

Category Tags: WTC Investigation, 9/11 Investigations

A bi-layered chip from the World Trade Center dust.A bi-layered chip from the World Trade Center dust. [Source: Open Chemical Physics Journal]Significant amounts of what appears to be a highly explosive material called nano-thermite are found in samples of dust that were collected at Ground Zero shortly after the 9/11 attacks, according to a 25-page scientific study published in the online, peer-reviewed Open Chemical Physics Journal. The paper is written by nine scientists and engineers. Its lead author is Niels Harrit, an associate professor of chemistry at the University of Copenhagen in Denmark.
Four Samples of WTC Dust Examined - The authors obtained four samples of dust from the World Trade Center collapses that had been collected by New York residents near the WTC. One of these samples was collected about 10 minutes after the second tower collapsed, thus eliminating any possibility of contamination by the steel-cutting or clean-up operations at Ground Zero, which began later on.
Red and Grey Chips Found - The paper reports that the authors discovered distinctive red and gray chips in all the dust samples, which showed marked physical and chemical similarities between all samples. Most of the chips measured between 0.2 and 3 mm. The properties of these chips were analyzed using optical microscopy, scanning electron microscopy (SEM), X-ray energy dispersive spectroscopy (XEDS), and differential scanning calorimetry (DSC).
Key Findings - Some of the key findings and conclusions of the authors’ analysis are:
bullet The XEDS analysis found that the red chip materials contained iron oxide (rust), aluminum, silicon, and carbon in tiny plate-like structures. The existence of elemental aluminum and iron oxide together indicated that the material “may contain thermite.” [Harrit et al., 2009; Deseret News, 4/6/2009; Russia Today, 7/9/2009] Thermite is an incendiary material composed of iron oxide and aluminum powder. [Popular Science, 8/19/2004; Deseret Morning News, 4/10/2006; BBC, 7/4/2008]
bullet After igniting several red/gray chips in the DSC at 700°C, numerous iron-rich spheres and spheroids were found in the residue. This indicated that a very high temperature reaction occurred, since the iron-rich product would have to be molten to form these shapes. In several spheres, the iron content significantly exceeded the oxygen content, leading the authors to conclude that a very high-temperature reduction-oxidation reaction had occurred, specifically the thermite reaction.
bullet The spheroids’ chemical signature strikingly matched the chemical signature of spheroids produced by igniting commercial thermite, and also matched the signatures of many of the microspheres previously found in the WTC dust by some of the study’s authors.
bullet As measured using DSC, the chips ignited and reacted vigorously at a temperature of about 430°C, with a narrow exotherm, matching closely an independent observation of a known nano-thermite sample. The low temperature of ignition and the presence of iron oxide grains of less than 120 nanometers showed that the material was not conventional thermite, which ignites at around 900°C, but very likely a form of nano-thermite (which is also called “super-thermite”).
bullet The authors conclude, “[T]he red layer of the red/gray chips we have discovered in the WTC dust is active, unreacted thermitic material, incorporating nanotechnology, and is a highly energetic pyrotechnic or explosive material.” [Harrit et al., 2009]
The study also cites an April 2000 report, which confirms that “the technology to make materials remarkably fitting the characterization of the red chips” that the authors discovered was available at least 17 months before 9/11. [Gash et al., 4/10/2000; Harrit et al., 2009]

Entity Tags: Niels H. Harrit

Category Tags: WTC Investigation, 9/11 Investigations

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Key Events

Key Day of 9/11 Events (101)Key Hijacker Events (145)Key Warnings (95)

Day of 9/11

All Day of 9/11 Events (1312)Dick Cheney (55)Donald Rumsfeld (33)Flight AA 11 (145)Flight AA 77 (145)Flight UA 175 (87)Flight UA 93 (242)George Bush (130)Passenger Phone Calls (67)Pentagon (127)Richard Clarke (32)Shanksville, Pennsylvania (23)Training Exercises (56)World Trade Center (89)

The Alleged 9/11 Hijackers

Alhazmi and Almihdhar (343)Marwan Alshehhi (134)Mohamed Atta (206)Hani Hanjour (72)Ziad Jarrah (74)Other 9/11 Hijackers (172)Possible Hijacker Associates in US (79)Alleged Hijackers' Flight Training (73)Hijacker Contact w Government in US (33)Possible 9/11 Hijacker Funding (42)Hijacker Visas and Immigration (135)

Alhazmi and Almihdhar: Specific Cases

Bayoumi and Basnan Saudi Connection (51)CIA Hiding Alhazmi & Almihdhar (120)Search for Alhazmi/ Almihdhar in US (39)

Projects and Programs

Al-Qaeda Malaysia Summit (172)Able Danger (60)Sibel Edmonds (61)Phoenix Memo (27)Randy Glass/ Diamondback (8)Robert Wright and Vulgar Betrayal (67)Remote Surveillance (241)Yemen Hub (75)

Before 9/11

Soviet-Afghan War (105)Warning Signs (452)Insider Trading/ Foreknowledge (53)US Air Security (75)Military Exercises (83)Pipeline Politics (67)Other Pre-9/11 Events (56)

Counterterrorism before 9/11

Hunt for Bin Laden (158)Counterterrorism Action Before 9/11 (225)Counterterrorism Policy/Politics (252)

Warning Signs: Specific Cases

Foreign Intelligence Warnings (35)Bush's Aug. 6, 2001 PDB (39)Presidential Level Warnings (31)

The Post-9/11 World

9/11 Investigations (657)9/11 Related Criminal Proceedings (22)9/11 Denials (29)US Government and 9/11 Criticism (67)9/11 Related Lawsuits (24)Media (47)Other Post-9/11 Events (77)

Investigations: Specific Cases

9/11 Commission (257)Role of Philip Zelikow (87)9/11 Congressional Inquiry (41)CIA OIG 9/11 Report (16)FBI 9/11 Investigation (146)WTC Investigation (112)Other 9/11 Investigations (135)

Possible Al-Qaeda-Linked Moles or Informants

Abu Hamza Al-Masri (102)Abu Qatada (36)Ali Mohamed (78)Haroon Rashid Aswat (17)Khalil Deek (20)Luai Sakra (12)Mamoun Darkazanli (36)Nabil Al-Marabh (41)Omar Bakri & Al-Muhajiroun (25)Reda Hassaine (23)Other Possible Moles or Informants (169)

Other Al-Qaeda-Linked Figures

Abu Zubaida (99)Anwar Al-Awlaki (17)Ayman Al-Zawahiri (81)Hambali (39)Khalid Shaikh Mohammed (139)Mohammed Haydar Zammar (44)Mohammed Jamal Khalifa (47)Osama Bin Laden (228)Ramzi Bin Al-Shibh (105)Ramzi Yousef (67)Sheikh Omar Abdul-Rahman (57)Victor Bout (23)Wadih El-Hage (45)Zacarias Moussaoui (159)

Al-Qaeda by Region

"Lackawanna Six" (13)Al-Qaeda in Balkans (168)Al-Qaeda in Germany (189)Al-Qaeda in Italy (55)Al-Qaeda in Southeast Asia (149)Al-Qaeda in Spain (121)Islamist Militancy in Chechnya (50)

Specific Alleged Al-Qaeda Linked Attacks or Plots

1993 WTC Bombing (73)1993 Somalia Fighting (13)1995 Bojinka Plot (78)1998 US Embassy Bombings (121)Millennium Bomb Plots (43)2000 USS Cole Bombing (114)2001 Attempted Shoe Bombing (23)2002 Bali Bombings (36)2004 Madrid Train Bombings (82)2005 7/7 London Bombings (87)

Miscellaneous Al-Qaeda Issues

Alleged Al-Qaeda Linked Attacks (89)Alleged Al-Qaeda Media Statements (102)Key Captures and Deaths (124)

Geopolitics and Islamic Militancy

US Dominance (112)Alleged Iraq-Al-Qaeda Links (255)Iraq War Impact on Counterterrorism (83)Israel (61)Pakistan and the ISI (470)Saudi Arabia (249)Terrorism Financing (312)Londonistan - UK Counterterrorism (322)US Intel Links to Islamic Militancy (69)Algerian Militant Collusion (41)Indonesian Militant Collusion (20)Philippine Militant Collusion (74)Yemeni Militant Collusion (47)Other Government-Militant Collusion (23)

Pakistan / ISI: Specific Cases

Pakistani Nukes & Islamic Militancy (37)Pakistani ISI Links to 9/11 (73)Saeed Sheikh (59)Mahmood Ahmed (30)Haven in Pakistan Tribal Region (179)2008 Kabul Indian Embassy Bombing (10)Hunt for Bin Laden in Pakistan (154)

Terrorism Financing: Specific Cases

Al Taqwa Bank (29)Al-Kifah/MAK (54)BCCI (37)BIF (28)BMI and Ptech (21)Bin Laden Family (62)Drugs (71)

'War on Terrorism' Outside Iraq

Afghanistan (299)Drone Use in Pakistan / Afghanistan (49)Destruction of CIA Tapes (92)Escape From Afghanistan (61)High Value Detainees (179)Terror Alerts (50)Counterterrorism Action After 9/11 (353)Counterterrorism Policy/Politics (432)Internal US Security After 9/11 (125)
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