Debunking the Real 9/11 Myths: Why Popular Mechanics Can’t Face up to Reality - Part 7

WTC 7 Fire and Column Failure

Written by Adam Taylor
23 November 2012

Editor’s note: This is Part 7 (see Part 6) of an extensive report by 9/11 researcher Adam Taylor that exposes the fallacies and flaws in the arguments made by the editors of Popular Mechanics (PM) in the latest edition of Debunking 9/11 Myths. We encourage you to submit your own reviews of the book at Amazon.com and other places where it is sold.

Part 7: WTC 7 Fire and Column Failure

(Quotes from Popular Mechanics’ book are shown in red and with page numbers.)

Although Popular Mechanics states the office fires in Building 7 reached temperatures of 1,100°F, both critics and supporters of the official story with technical expertise have pointed out that there is no evidence for fires that hot.

The Popular Mechanics chapter regarding the mysterious collapse of WTC 7 shows itself to be no more promising than its previous chapter on the Twin Towers. PM begins this section by summarizing the history of the controversy surrounding Building 7 and the numerous investigations carried out regarding its collapse. PM correctly notes that many agencies were located in the building as tenants, including the Secret Service, Central Intelligence Agency, Department of Defense, Internal Revenue Service, Securities and Exchange Commission, and New York City’s Office of Emergency Management. i  The chapter discusses the initial FEMA investigation and how, after FEMA failed to provide an explanation for Building 7’s collapse, the task was then handed over to NIST. PM touts the NIST report on Building 7 as having finally proved the building was not destroyed with explosives. Contrary to PM’s assertion that the reason for WTC7’s collapse is “ less complicated and even more remarkable” (pg 66) than… controlled demolition, it is apparent that the cause of collapse is still demolition, and that the NIST WTC7 report utterly fails to provide a reasonable explanation of what actually caused the collapse of the building.

The first section of PM’s WTC7 chapter mainly discusses the fire and damage to Building 7 and how this supposedly caused the building to collapse. Here is a summary of what NIST claims caused the collapse of WTC7:

  1. The fires caused sufficient thermal expansion in the steel beams on the east side of WTC 7 to force the steel girder connecting Columns 44 and 79 to lose its connection with the latter, and to damage the floor framing on floors near Column 79
  2. The loss of that girder’s connection to Column 79, along with fire-induced damage to the floor systems around Column 79, caused Floor 13 to collapse.
  3. The collapse of Floor 13 caused all the floors below it down to Floor 5 to collapse.
  4. Column 79, being left with inadequate lateral support, buckled between Floors 5 and 14.
  5. This buckling caused the downward movement of Column 79 (which caused the collapse of the east penthouse).
  6. Columns 80 and 81, having also lost support, buckled, causing all the floors on the east side of WTC7, which had been weakened by the fire, to collapse.)
  7. All the other interior columns then failed, leaving the building a hollow shell.
  8. After most of the collapse had already occurred in the building’s interior, where it could not be seen from the outside, the exterior columns failed, completing the collapse.  ii 

However, each of these points in this fantastic scenario is problematic:

  1. Though PM claims that the fires in WTC7 reached temperatures ranging from 299°C (570°F) to 593°C (1,100°F), scientists on both sides of the argument have concluded that the fires could not have become this hot and could not have reached the temperatures claimed by NIST:
  2. The fire that NIST claims started the collapse (via thermal expansion of long-span beams) had actually burned out in the area of the collapse more than an hour before the collapse. It could not, therefore, have caused the collapse at 5:20 p.m., as NIST claims:

    Examination of the photographs in the Final Report shows that the fire had burned out in the area of the collapse more than an hour before the collapse.

  3. NIST arbitrarily added 10% to the result of their Fire Dynamics Simulator (FDS). This is simply not done in a scientific analysis:
  4. NIST applied this arbitrarily increased temperature for 4 hours of heating, ignoring their statement that the fires lasted only 20 to 30 minutes in any location. :
  5. Popular Mechanics repeats NIST’s claim that the failure of column 79 caused the collapse of the entire building, even though the scientific evidence contradicts this theory.
  6. NIST applied the 4 hours of heating in 1–½ seconds over the entire northeast part of the floor, again creating an unrealistic situation and result:
  7. NIST heated the steel beams, but not the concrete slab above, and then claimed that the temperature differential caused the shear studs to fail. In reality, the fire would have heated them both nearly uniformly – without significant differential expansion.

    Concrete expands at 85% the rate of steel. Leaving this expansion out of the calculations in order to show failure of the shear studs is both unscientific and fraudulent.

Certainty of impending collapse

David Ray Griffin noted in The Mysterious Collapse of WTC Seven: Why NIST’s Final 9/11 Report is Unscientific and False:


This series began with Part 1, Introduction. For Part 6 click here.


  1.  ↑ For the full list of WTC7 tenants, see: http://wtc7.net/background.html
  2.  ↑ Summary adapted from The Mysterious Collapse of World Trade Center 7, by David Ray Griffin, pg 210–211
  3.  ↑ Quoted from: http://911review.com/articles/ryan/NIST_WTC7.html
  4.  ↑ Quoted from: http://www.cool–places.0catch.com/911/ GreeningCommentsNCSTAR1-9.pdf
  5.  ↑ NIST “L” pg 26 [pdf pg 30]
  6.  ↑ NIST NCSTAR 1A pg 32 [pdf pg 74] http://www.nist.gov/customcf/ get_pdf.cfm?pub_id=861610
  7.  ↑ NIST NCSTAR 1A pg 36 [pdf pg 78]
  8.  ↑ NIST NCSTAR 1–9 Vol. 2 pg 493 [pdf pg 155]:http://wtc7.net/background.html
  9.  ↑ NIST NCSTAR 1–9 Vol. 1 pg 352 [pdf pg 396]
  10.  ↑ NIST NCSTAR 1–9 Vol. 1 pg 352 [pdf pg 396]