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Fire Did Not Cause Building 7’s Collapse on 9/11, New Study Finds

On September 11, 2001, at 5:20 PM, the 47-story World Trade Center Building 7 collapsed into its footprint, falling more than 100 feet at the rate of gravity for 2.5 seconds of its seven-second destruction.

Despite calls for the evidence to be preserved, New York City officials had the building's debris removed and destroyed in the ensuing weeks and months, preventing a proper forensic investigation from ever taking place. Seven years later, federal investigators concluded that WTC 7 was the first steel-framed high-rise ever to have collapsed solely as a result of normal office fires.

Today, we at Architects & Engineers for 9/11 Truth are pleased to partner with the University of Alaska Fairbanks (UAF) in releasing the draft report of a four-year computer modeling study of WTC 7’s collapse conducted by researchers in the university's Department of Civil and Environmental Engineering. The UAF WTC 7 report concludes that the collapse of WTC 7 on 9/11 was caused not by fire but rather by the near-simultaneous failure of every column in the building.

Download the Report | Read the Abstract

The Alt Tag

Project Information

Lead Researcher

Dr. J. Leroy Hulsey
Professor of Civil Engineering, University of Alaska Fairbanks

Research Assistants

Dr. Feng Xiao
Associate Professor, Nanjing University of Science and Technology

Dr. Zhili Quan
Bridge Engineer, South Carolina Department of Transportation

Project Dates

May 1, 2015 – December 31, 2019


$316,153 (provided by Architects & Engineers for 9/11 Truth)

Simulations and Videos

Open Data

All input data, results data, and simulations that were used or generated during this study can be downloaded as a ZIP file by clicking the link below:

Download UAF WTC 7 Files

Please be advised that the size of this ZIP file is 256 GB and that, after unzipping the file, the size of the folder containing all of the files is 632 GB. Therefore, downloading the ZIP file and unzipping it will require approximately 900 GB of storage space.

Help Ensure an Open and Transparent Scientific Process

The files contained in this download will enable any person with the requisite software tools to examine and replicate all of the computer analyses performed during this study.

Unfortunately, while the UAF research team has made all of its data available to the public, the National Institute of Standards and Technology (NIST) has so far refused to practice the same level of transparency regarding its taxpayer-funded investigation into the collapse of WTC 7.

In 2009, then-NIST Director Patrick Gallagher issued a “Finding Regarding Public Safety Information” stating that the disclosure of certain information related to the NIST WTC 7 investigation “might jeopardize public safety.” Since then, NIST has cited this public safety exemption as grounds for withholding key portions of its modeling data and other information from members of the public — including from licensed engineers, whose foremost duty is to protect the safety, health, and welfare of the public.

In response to one engineer’s appeal of NIST’s decision to withhold this information, the U.S. Department of Commerce subsequently claimed that, if released, the withheld information “might provide instruction to groups and individuals that wish to learn how to simulate building collapse and devise ways to destroy buildings.”

Architects & Engineers for 9/11 Truth, which represents thousands of professionals who are tasked with ensuring the public’s safety, vigorously objects to the withholding of any information related to the NIST WTC 7 investigation. It should be clear to all observers that the risk of anyone using this information to devise ways to destroy buildings is infinitesimal to zero and that the withholding of this information has merely served to prevent the public from scrutinizing the analyses performed by NIST.

We therefore encourage every member of the public who cares about ensuring an open and transparent scientific process regarding the collapse of WTC 7 to email NIST Director Walter Copan at walter.copan@nist.gov and respectfully ask him to annul the 2009 “Finding Regarding Public Safety Information.” This simple action would allow NIST to disclose any information related to its WTC 7 investigation that members of the public request in the future.

In your email to Director Copan, please copy Catherine Fletcher (catherine.fletcher@nist.gov), NIST’s FOIA officer, and Gail Porter (gail.porter@nist.gov), director of NIST’s Public Affairs Office, as well as nist@ae911truth.org so that we can track how many requests Copan receives.

Public Comment Period

Following the release of the UAF WTC 7 draft report on September 3, 2019, there was a two-month public comment period that ended on November 15, 2019.

During this period, the UAF research team and AE911Truth staff welcomed any and all members of the public to submit constructive comments intended to further the analyses and presentation of findings contained in the report. Commenters were asked to send their comments in an attached PDF or Word document to publiccomment@AE911Truth.org (any follow-up questions can be sent to this email address). Designated reviewers external to UAF and AE911Truth also reviewed the report during this period.

The final report will be released in early 2020.


UAF Event Poster thumb

There will be several presentations given in conjunction with the release of the UAF WTC 7 draft report and final report, so please stay tuned for presentations being given in your area as well as presentations being streamed and/or archived online.

The first presentation was given in UAF’s Schaible Auditorium on September 3, 2019, and is archived at https://media.uaf.edu.

The second presentation was given at the Faculty Club at UC Berkeley on September 5, 2019.