Written by Adam Taylor
Architects & Engineers for 911 Truth
March 1, 2012

Plane Impacts, Fire Damage & Melted Steel

Editor’s note: This is Part 2 of an extensive report by researcher Adam Taylor that exposes the fallacies and flaws in the arguments made by 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.

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

Plane Impacts and Fire Damage

PM next turns to the issue of the plane impacts and fire damage and their roles in the WTC event. Though PM acknowledges that the fires in the buildings could not have become hot enough to melt steel, they nonetheless rehash the constantly heard argument from other defenders of the official story that the steel did not need to melt to cause collapse. According to PM, it only had to be weakened by the fires enough to cause collapse.

PM argues that “When the planes hit the buildings and plowed into their centers, a large section of the exterior load-bearing columns as well as some crucial core columns were severed.” (pg. 37-38) Though this may be true, the collapse of the Towers appears to have actually started at floors that had minimal structural damage.1 PM also discusses the theory from the National Institute of Standards and Technology (NIST) that “the impact stripped fireproofing insulation from the trusses that supported 80,000 square feet of floor space.” (pg. 38) This assertion, however, is greatly flawed, as noted by UL whistleblower Kevin Ryan:

[NIST’s] test for fireproofing loss, never inserted in the draft reports, involved shooting a total of fifteen rounds from a shotgun at non-representative [structural steel] samples… it’s not hard to see that these tests actually disproved their findings. One reason is that there is no evidence that a Boeing 767 could transform into any number of shotgun blasts. Nearly 100,000 blasts would be needed based on NIST’s own damage estimates, and these would have to be directed in a very symmetrical fashion to strip the columns and floors from all sides. However, it is much more likely that the aircraft debris was a distribution of sizes from very large chunks to a few smaller ones, and that it was directed asymmetrically.2
Photo from Ground Zero shows a portion of the airplane fuselage, which contradicts the framework of NIST’s “shotgun test” for fireproofing loss in the Twin Towers

Photo from Ground Zero shows a portion of the airplane fuselage, which contradicts the framework of NIST’s “shotgun test” for fireproofing loss in the Twin Towers

Ryan’s assertion that “…aircraft debris was a distribution of sizes from very large chunks to a few smaller ones” is well grounded, as photographs show that large portions of the planes exited the Towers, and eyewitnesses who escaped from the Towers reported seeing intact portions of the plane in the building.3

PM next goes on to discuss NIST’s assertions that the fires in the buildings were sufficient to weaken the steel to the failure point. However, NIST’s own tests show no evidence of this. While PM asserts in their book that “[steel] loses roughly 50 percent of its strength at approximately 600 degrees Celsius (1,100 Fahrenheit)” (pg. 38), NIST cites no evidence that the steel in the Towers sustained temperatures anywhere near this range. The highest temperatures NIST estimated for the steel samples was only 250 °C (482 °F), according to the metallographic paint tests they performed on WTC core column specimens.4

PM attempts to make a case that the combination of the aircraft impacts and the ensuing fires were sufficient to cause both of the structures to collapse.

Conspiracy theorists point to other high-rise fires, such as the one in 1991 at the 38-story Meridian Plaza hotel in Philadelphia, as proof that fire alone cannot bring down a skyscraper. And, in a sense, they are right: Fire alone did not bring down the towers. (pg. 40)

It is important to note that the term “conspiracy theorists” is a derogatory term used here to discredit the forensic evidence of controlled demolition brought forward by technical professionals. The experts at AE911Truth do not speculate on possible theories regarding who brought down the WTC skyscrapers.

In the case of Building 7, the NIST report tells us that structural damage played no role in initiating the collapse of the building, and that its collapse was due to “normal office fires”.5

One then has to wonder why PM does not consider the 9/11 Truth movement “in a sense right” about Building 7. But that aside, it is important to quantify how the structural damage played a role in the collapse of the Towers. We previously noted that the collapse of the Towers started on floors with less damage than other floors. In the case of the North Tower, the collapse started at the 98th floor6, which had the least amount of structural damage out of all the damaged floors.7 Not only that, but the upper section of the North Tower started to collapse on the side of the building opposite to where the plane impacted.

Link to the rest of the article