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NIST Admits 9/11 Collapse Unexplainable
(from infowars.net)

Implicitly acknowledges controlled demolition only means by which towers could have fallen at free fall speed

The National Institute for Standards and Technology has been forced to admit that the total free-fall collapse of the twin towers cannot be explained after an exhaustive scientific study, implicitly acknowledging that controlled demolition is the only means by which the buildings could have come down.

In a recent letter (PDF link) to 9/11 victim's family representatives Bill Doyle and Bob McIlvaine, NIST states, "We are unable to provide a full explanation of the total collapse."

A 10,000 page scientific study only offers theories as to how the "collapse initiation" proceeded and fails to address how it was possible for part of a WTC structure to fall through the path of most resistance at freefall speed, completely violating the accepted laws of physics.

In addition, NIST's own studies confirmed that virtually none of the steel in either tower reached temperatures hotter than 500 degrees. The point at which steel weakens is 1000 degrees and melting point is reached at 1,500 degrees, according to NIST itself.

"NIST'S 10,000-page report purports to explain what it calls "collapse initiation" -- the loss of several floors' vertical support," writes Kevin Barrett of Scholars for 9/11 Truth. "In order to dream up this preposterous scenario, NIST had to ignore its own tests that showed that virtually none of the steel got hotter than 500 degrees f. It had to claim that somehow the planes took out many core columns, despite the fact that only a direct hit by an engine would have been likely to do so, and that the chances of this happening even once are fairly low. It had to preposterously allege that the plane that nicked the corner of the South Tower took out more core columns than the one that hit the North Tower almost dead center. It had to tweak all the parameters till they screamed bloody murder and say that the steel was far weaker than it actually was, the fire was far hotter than it actually was, the sagging was far greater than it actually was, and so on. And so NIST hallucinated a computer-generated fantasy scenario for "collapse initiation"--the failure of a few floors."

"But how do you get from the failure of a few floors to total collapse at free-fall speed of the entire structure? The short answer: You don't. Anyone with the slightest grasp of the laws of physics understands that even if all of the vertical supports on a few floors somehow failed catastrophically at exactly the same moment--a virtually impossible event, but one necessary to explain why the Towers would come straight down rather than toppling sideways--the top part of the building could not fall THROUGH the still-intact, highly robust lower part of the building, straight through the path of most resistance, just as fast as it would have fallen through thin air."

"Thus total free-fall collapse, even given NIST's ridiculous "initiation" scenario, is utterly impossible. The probability of it happening is exactly equal to the probability of the whole building suddenly falling upward and landing on the moon," concludes Barrett.

NIST have yet to properly address the sudden freefall collapse of WTC Building 7, which imploded on the late afternoon of 9/11 despite not being hit by a jetliner.

In August 2006, NIST promised to scientifically evaluate whether explosive devices could have contributed to the 47-story building's collapse but no answers have been forthcoming.

In August of this year, James Quintiere, Ph.D., former Chief of the Fire Science Division of the National Institute of Standards and Technology, called for an independent inquiry into NIST's investigation of the collapse of the twin towers.

Quintiere said NIST's conclusions were "questionable", that they failed to follow standard scientific procedures and that their failure to address Building 7 belied the fact that the investigation was incomplete.
 
 
   
 

NIST Report: One Year Later

Still Dead On Arrival

By Mark H. Gaffney

 
A note to the reader: In December 2006 Mark H. Gaffney posted a scathing critique of the US government’s official report about the WTC collapse on 9/11. One year later, the case is stronger than ever. * * 

01/04/08 "ICH " -- - -In August 2002 the US Congress authorized the National Institute for Safety and Transportation (NIST) to investigate the collapse of the World Trade Center on 9/11. The official instruction was not limited to conducting a building performance study, as some have claimed.[1] The primary stated objective of the investigation was to determine the cause of the collapse–––no less.[2] 
 

When NIST released its final report in September 2005, critics charged that the agency had ignored evidence of explosions in the towers. The agency responded by asserting its scientific laurels. NIST insisted that its “200 technical experts” had conducted “an extremely thorough investigation.” NIST boasted that its staff “reviewed tens of thousands of documents, interviewed more than 1,000 people, reviewed 7,000 segments of video footage and 7,000 photographs, analyzed 236 pieces of steel from the wreckage, performed laboratory tests and sophisticated computer simulations,” yet, found “no corroborating evidence for a controlled demolition.” NIST also claimed that it had considered “a number of hypotheses for the collapse of the towers.”[3] 
 
No doubt, many Americans were persuaded by this snow-job. Sad to say, few of our countrymen (or women) bother to read official reports, especially when they run to 10,000 pages. The persistent individuals who do, however, know that there are sound reasons to question all of the above; because a close reading of the NIST report shows that the agency assumed from the beginning that the Boeing 767 impacts and subsequent fires were responsible for the collapse of the twin towers. The report gives no consideration whatsoever to alternative hypotheses, including the possible use of explosives, the leading candidate. Far from exploring other scenarios, NIST simply took it for granted that the impacts set in motion a chain of events leading to a catastrophic structural failure. Working backwards, NIST scientists searched for evidence that supported their predetermined conclusion. Everything else was ignored or excluded. If it is not already evident to the reader, this is no way to conduct a scientific investigation. NIST then had the audacity to imply that it arrived at its favored collapse model through an exhaustive process of elimination. Most readers who merely browsed NIST’s 2005 Executive Summary probably were not aware that NIST’s stated conclusion was really an assumption. Consider this passage, for example:
 
“The tragic consequences of the September 11, 2001 attacks were directly attributable to the fact that terrorists flew large jet-fuel laden commercial airliners into the WTC towers. Buildings for use by the general population are not designed to withstand attacks of such severity; building codes do not require building designs to consider aircraft impact.”[4] 
 
The above comment about building codes is deceptive–––NIST readily concedes in its report that the towers survived the initial impacts. In fact, John Skilling, the structural engineer who designed the WTC, always claimed that they would. The towers survived, despite serious damage, because they were hugely overbuilt, redundant by design. Although the WTC’s soaring lines gave the impression of a relatively light frame, in fact, the twin towers were extremely rugged buildings, engineered to withstand hurricane-force winds and even a direct hit by a Boeing 707, the largest commercial jetliner of the day. Some have argued that the newer Boeing 767s caused much more damage because of their larger size, but in fact, the two Boeings are comparable. Although slightly smaller, the 707 has a greater cruise speed of 600 mph (as compared with 530 mph for a Boeing 767). Assuming both were to crash at this speed, the 707 would actually have greater kinetic energy.[5] 
 
After the Boeing 767 impacts on 9/11 the severed steel columns simply transferred the weight of the building to other undamaged columns. The NIST report even states that the towers would probably have stood indefinitely, if the impacts had not dislodged the fireproofing material that protected the steel from fire-generated heat.[6]  Construction-grade steel begins to lose strength at 425°C (~800°F) and is only about half as strong at 650°C (1,202°F). NIST argues in its report that the crashed jetliners damaged or dislodged 100% of the protective insulation within the impact zone, while also spilling many thousands of gallons of jet fuel over multiple floors. The resulting 800-1,000°C (1,440-1,800°F ) blaze–––the report claims–––seriously weakened the now-exposed steel, leading to a global structural failure. In order to understand the official story, however, and why it fails to explain the WTC collapse, it is necessary to know more about the World Trade Center and how it was built.
 
A State-of-the-Art Design

 
Upon its completion in 1970 the north tower of the Trade Center soared 1,368 feet tall–––100 feet higher than the Empire State Building. In addition to being the world’s tallest skyscraper, it was a state-of-the-art achievement of high-rise construction.[7] Designed by architect Minoru Yamasaki, the WTC was one of the first skyscrapers to feature large expanses of unobstructed floor space within a steel-frame building. Although commonplace today, this was a novel idea in the 1960s, as it required doing away with the forest of columns so typical of the skyscrapers of former years. Chief engineer John Skilling achieved the objective of open space with a double support system: the first so-called tubular design, consisting of a dense array of 240 columns around the outer wall or perimeter, and a network of 47 huge columns at the core. The core columns supported about 53% of the weight of each building, and were massive, up to 52 inches wide.[8] The steel in these monster columns was seven inches thick at the base.[9]
 
The core columns were of two types: box columns at the foot of the buildings, gradually transitioning to rolled wide-flange beams (“I” beams) higher up. The core of each tower, including the elevators and stairwells. was surrounded by expansive office space. The perimeter wall supported 47% of the weight and also resisted the force of the wind. These exterior columns were reinforced with broad steel plates known as “spandrels,” which girdled the building, like ribs, at every floor. Although the core columns gradually increased in size from top to bottom, for aesthetic reasons the external dimensions of the perimeter columns had to be the same all the way down, hence, required the use of heat-treated steel. For this reason Skilling’s new tubular concept only became possible with the introduction of high-strength steels in the 1960s. Prefabrication and a modular design were other innovations that kept costs down and allowed for speedy construction.
 
Both inner and outer sets of columns were joined together by an innovative system of lightweight steel trusses. Each floor consisted of a truss assembly, over which was laid a corrugated steel deck–––the bed for a poured four-inch slab of concrete.  Although lightweight, the floor design was so sound that it easily supported the weight of libraries, file rooms, and heavy safes without the need for additional strengthening.[10] The lightweight truss assemblies were vulnerable to fire damage, however, because they consisted of rather thin steel members. For this reason, at the time of construction the trusses were spray-coated with protective insulation, 0.75 inch thick, and this was later upgraded to an average thickness of more than two inches.[11] (The technical term for this insulation is Spray-applied Fire Resistant Material = SFRM) The core columns had a fire-barrier of gypsum wallboard. 
 
NIST argues that the Boeing impacts jarred loose this protective insulation from the steel trusses and columns. The subsequent fires then weakened the exposed trusses, causing them to sag. This, in turn, pulled the perimeter columns inward. The fires also weakened both sets of columns and at a critical point the perimeter wall buckled. NIST makes the claim that its investigation showed conclusively that the initiation occurred in the perimeter wall, triggering a global collapse.[12] Did the agency prove its case? In a moment I will explore this question. Before I do, however, it is important to understand what NIST did not investigate.
 
What NIST failed to investigate

 
Despite its broad charge to investigate the WTC collapse, NIST limited the scope of its investigation to the sequence of events from the first plane impacts to the onset of collapse. This means, of course, that NIST failed to study the collapse itself. This narrow focus–––some would call it sleight-of-hand–––allowed NIST to side-step a number of important issues. No doubt, this was the intent, since investigating them would surely have led NIST scientists to very different conclusions. The first and foremost of these issues was the near free-fall speed of the collapse. Videos filmed on 9/11 confirm that the towers plummeted as if there was no resistance whatsoever. But how can this be, given the enormous inertial mass of the building itself, which should have resisted and slowed the fall considerably? Even if we assume that the columns in the impact zone failed, the rest of the columns in the towers were untouched by the plane impacts and fires, therefor, suffered no loss of strength. These stone-cold columns should have resisted the fall. Although the exact time of the collapse of WTC 1 and 2 cannot be determined with precision because of the growing dust cloud, each collapse took approximately 10-12 seconds, only 1-2 seconds slower than the time for a billiard ball to free-fall from the WTC roof to the plaza.  But how can this be? By what special dispensation did the collapsing WTC violate the laws of physics? The reader will search the NIST report in vain for any discussion of this important anomaly. Why not? Obviously. because agency officials made a political decision not to go there.
 
No less puzzling was the fact that the collapses were total and nearly symmetrical. This means, of course, that when the collapses began all of the columns on that floor failed at precisely the same moment. But, again, how could this happen? Even if we assume that the plane impacts severed or damaged a number of columns in the impact zone, and even if we also assume that the fires weakened a number of other nearby columns, the majority of columns in the buildings and even on the affected floors were still at full strength at the moment of collapse. The collapses were also total. The rubble from the buildings fell through the plaza level and piled up in the basements. Photos by Joel Meyerowitz and others show that the piles of wreckage were about six stories high, as evidenced by surviving portions of the perimeter wall. The wreckage reached the level of the column tree–––a convenient reference point–––where the larger exterior columns around the base divided into three smaller columns above. The totality of the collapse is hard to explain because, as noted, the largest and strongest columns were in the lower part of the buildings. The towers encountered increasing mass, i.e., resistance, as they fell. For this reason, at least one engineer has argued that the WTC collapse should at some point have self-arrested.[13] Other experts hotly dispute this, however, and the matter remains controversial.[14] Engineers clearly are fascinated by this question. Although a more detailed discussion is beyond the scope of this article, it is evident that media coverage has often served to confuse the issue rather than clarify. In a recent 9/11 documentary on the History Channel, for example, a debunker glibly described the events at Ground Zero as a “classic progressive collapse,” as if this were a well-known or frequent phenomenon.[15] But this is plainly false. As noted–––and I must emphasize it again–––no steel-frame skyscraper had ever collapsed before 9/11, nor has any since. 
 
By the way, there is an excellent reason why they do not fall down. Structural steel happens to be an extremely tough and forgiving substance–––the reason it is the pre-eminent building material used in high-rise construction. As the 9/11 Commission Report concedes, none of the NYFD chiefs anticipated a catastrophic structural failure on 9/11, despite the fires and impacts.[16]  Had they believed a general collapse was possible, the chiefs would not have established their emergency command posts in the lobbies of the stricken towers. Nor would they have ordered hundreds of New York City firemen to begin the long climb up the stairwells to aid the victims and assist with the evacuation. As we know, 343 of them perished. According to the official report, at least one of the fire chiefs did express concern about the danger of a partial collapse on the upper floors.[17] No doubt, this individual was as shocked as everyone else by the totality and near-perfect symmetry of the collapses that ensued–––both standard features of controlled demolitions and virtually unknown in random fire events. After I posted a critique of the NIST report in December 2006, I received a letter from a retired fireman who informed me that over the course of his twenty-odd years of service he had fought many types of fires, involving residential, commercial and industrial structures, including high-rise buildings. He explained that on a number of occasions, when his crew lost the battle to save a structure “some of the times the building would collapse…. in a random, haphazard, piecemeal fashion. Not once,” he wrote, “did I personally witness one of those structures collapsing in the rather controlled...fashion as the WTC towers and Building 7.”[18]
 
Another anomaly was the pulverization of material. Through history, concrete buildings have been known to collapse during powerful earthquakes, and when this occurs they typically fold up like an accordion, leaving a succession of concrete slabs, one piled on top of another, each plainly discernible in the rubble. But nothing like this occurred on 9/11. Photos of the mountain of wreckage at Ground Zero show very few, if any, large chunks of concrete. The rubble pile consisted almost exclusively of twisted steel. The conspicuous absence of concrete is remarkable, since concrete was the main constituent of the 500,000 ton towers. As noted, each floor of the 110-story building, roughly an acre in size, consisted of a slab of poured concrete, most of which was pulverized during the collapse into small pieces and fine dust. Some have attributed this to the force of gravity, but videos of the collapse dispute this. The buildings were not pulverized as they hit the ground, they disintegrated in midair. As the south tower started to collapse, for example, the entire upper section tipped as a unit, then inexplicably turned to dust before our eyes. Much of this dust settled a foot deep on the sixteen-acre WTC site. The rest was deposited across lower Manhattan. Nor was the pulverization limited to concrete. Other construction materials also disappeared without a trace, including glass, office furniture and tens of thousands of computers, not to mention the many victims. It’s a fact that less than 300 corpses were recovered. Most of the victims were identified solely from body parts. Strangely, when workmen began to dismantle the badly damaged Deutsch Bank on December 8, 2006, they found more than 700 slivers of bone on the roof and within the structure.[19] This bizarre report has never been explained.
 
And there were other anomalies. The video record plainly shows that during the WTC collapse, perimeter columns weighing twenty tons or more were hurled as far as 500-600 feet from the towers. One remarkable photo of Ground Zero taken from above shows that entire sections of WTC-1’s western perimeter wall were thrown 500+ feet toward the Winter Garden.[20] Could a gravitational collapse do this? Doubtful. The NIST report not only fails to address any of these issues, it doesn’t even try. The report makes reference to the “global collapse” of the towers, but we never learn precisely what this means because NIST never informs us. By limiting the scope of its inquiry NIST rendered the truth unobtainable–––an effective way to neuter an investigation.

 
With all of this in mind, let us now explore what NIST did investigate.
 
The Special Projects

 
The NIST investigation was comprised of eight separate projects, which all together produced 43 volumes of supporting documentation. The projects included metallurgical studies, an impact analysis, an attempt to reconstruct the fires, and a computer model of the probable sequence of events leading to the collapse of each tower. Some of the agency’s research was of excellent quality–––some was not. But the main problem is that none of it lends credence to NIST’s official conclusions. 
 
Probably the most serious obstacle NIST investigators faced was a lack of information about the dynamic conditions that existed in the core of the towers on 9/11.[21] To be sure, thousands of photographs and hundreds of hours of videotape made it possible to study in detail the damage to the WTC exterior, and to gain a reasonable understanding about conditions in the outer offices. Fires were often visible through the windows, despite dense smoke, and structural damage in the impact zone, such as collapsed floors, was also discernible. However, as the NIST report states, “Fires deeper than a few meters inside the building could not be seen because of the smoke obscuration [sic] and the steep viewing angle of nearly all the photographs.”[22] This is an important admission, and one that NIST repeats a number of times. For example, in one of the supplementary documents NIST scientists qualify their analysis of the effects of the fire upon the steel with the following caveat:
 
“As conditions within the building core could not be determined from the photographic database, it was unknown what environment the recovered core columns may have experienced.”[23]

 
As we will see, this candid statement haunts the entire report. In fact, the only physical evidence NIST had about the actual conditions at the core was the data it was able to glean from 236 steel columns, panels, trusses, and other smaller samples recovered from the WTC ruin.[24] Metallurgical testing of these steel samples was probably the most important work NIST carried out, because this was the foundation for the rest of the investigation.  
 
The Metallurgical Studies

 
Thanks to the original labeling system used during the construction of the WTC, NIST was able to identify many of the samples it had gathered, and to determine with precision their locations in the WTC. As it happened, a number of the columns were from the impact and fire zones.[25] Although the collection represented only 0.25 - 0.5 % of the 180,000 total tons of structural steel used in the two towers, NIST scientists believed their sampling was adequate to determine the quality of the steel and to evaluate its performance on 911.[26]
 
 
The metallurgical findings decisively refuted the pancake theory of collapse widely reported in the media after 9/11. The pancake enthusiasts had argued that the weak link in the WTC was the point of attachment where the trusses connected with the inner and outer columns. These junctions, referred to as angle-clips, were made of relatively lightweight steel and were secured by steel bolts. During a 2002 NOVA television special MIT engineer Thomas Eagar explained the pancake model and why in his opinion the trusses had failed:

 
“...the steel had plenty of strength, until it reached temperatures of 1,100º to 1,300ºF. In this range, the steel started losing a lot of strength, and the bending became greater. Eventually the steel lost 80 percent of its strength, because of this fire that consumed the whole floor....then you got this domino effect. Once you started to get angle-clips to fail in one area, it put extra load on other angle-clips, and then it unzipped around the building on that floor in a matter of seconds. If you look at the whole structure, they are the smallest piece of steel. As everything begins to distort, the smallest piece is going to become the weak link in the chain. They were plenty strong for holding up one truss, but when you lost several trusses, the trusses adjacent to those had to hold two or three times what they were expected to hold.”[27]
 
 
According to the pancake theory, when one floor collapsed it set in motion a chain reaction. Although this initially seemed plausible, it turned out that Eager seriously underestimated the robustness of the World Trade Center. The earlier FEMA study found no indication of substandard materials or construction. On the contrary, FEMA found that “many structural and fire protection features of the design and construction were….superior to the minimum code requirements.”[28] The NIST investigation bore this out. For example, NIST confirmed that the truss assemblies were not only bolted to the outer perimeter wall, they were also welded, hence, were considerably stronger than expected–––not prone to pancaking.[29] Nor could the pancake model explain the failure of the core columns.

 
The WTC steel turned out to be significantly stronger than expected. Tests showed that the yield strengths of 87% of all steel tested exceeded the original specifications. For instance, the perimeter columns exceeded their specifications by more than 10%. The strength of the steel in the truss assemblies was also much higher than required. In many of the trusses, 50 ksi steel was used, even though the specifications called for only 36 ksi.”[30] (1 ksi = 1,000 lb/per square inch) NIST also tested a number of recovered bolts, and found that these too were stronger than expected, based on reports from the contemporaneous literature.[31] While all of these findings refuted the pancake theory, notice, they also failed to support NIST’s own preferred collapse model. One need not be a rocket scientist to see that the stronger the steel the less likely it was to fail on 9/11.
 
The Fire Tests:
Core Weakening?

 
In another series of tests NIST sought to address the alleged weakening of the WTC support columns. During a first-run, investigators placed an uninsulated steel column in a furnace where temperatures reached 1,100ºC (2,012ºF). During the test the surface temperature of the exposed column reached 600ºC in just 13 minutes–––the temperature range where significant loss of strength occurs. When the test was repeated with a column treated with SFRM insulation, the steel did not reach 600ºC even after ten hours. NIST concluded that “the fires in WTC-1 and WTC-2 would not be able to significantly weaken….insulated.…columns within the 102 minutes and 56 minutes, respectively, after impact and prior to collapse.”[32] NIST interpreted these results as validating its theory that the critical factor on 9/11 leading to the global failure was the damage to and removal of the SFRM fireproofing insulation caused by the Boeing 767 impacts. But was this an unwarranted leap? Let us now explore this question. 

 
NIST scientists developed a novel way to evaluate the impact of the fire on the WTC steel. According to the report, the approach was “easy to implement and robust enough to examine the entire component in the field.”[33] They found that the original primer paint used on the steel beams and columns was altered by high heat. This made it possible to determine the level of exposure by analyzing the paint on the samples.[34]  But the results were surprising. NIST found no evidence that any of the steel samples, including those from the impact areas and fire-damaged floors, had reached temperatures exceeding 1,110ºF (600ºC).[35] Sixteen recovered perimeter columns showed evidence of having been exposed to fire, but even so, out of 170 areas examined on these columns only three locations had reached temperatures in excess of 250ºC (450ºF).[36] Moreover, NIST found no evidence that any of the recovered core columns had reached even this minimal temperature.[37] The startling fact is that NIST’s own data failed to support its conclusion that the fires of 9/11 heated up the steel columns, causing them to weaken and buckle.

 
How might we explain this absence of evidence? Shyam Sunder, NIST’s lead scientist, probably offered a partial answer when he admitted that “the jet fuel....burned out in less than ten minutes.”[38] Also, the actual amount of combustibles in the WTC turned out to be less than expected–––considerably less. In its 2002 report FEMA had noted that 

 
“fuel loads in office-type occupancies typically range from about 4-12 psf [pounds per square foot], with the mean slightly less than 8 psf….At the burning rate necessary to yield these fires, a fuel load of about 5 psf would be required to maintain the fire at full force for an hour...”[39] 

 
Yet, when NIST scientists crunched the numbers they found that a typical floor of the WTC did not even have this minimum level of combustibles. The average was only about 4 psf.[40] The shocking fact is that the twin towers were fuel-poor, compared with other office buildings: a finding, notice, that does not support the frequent depictions in the media of a ferocious inferno raging beyond anything in human experience. More importantly, neither does it support NIST’s favored collapse scenario. The spillage of jet fuel ignited the combustibles, spreading the fires at a faster rate than would otherwise have occurred. Yet, for this same reason the fires also burned out sooner, because the fuel load was so low. Indeed, NIST scientists estimated that on average the WTC fires burned through the available combustibles at maximum temperatures (1,000ºC) in only about 15-20 minutes.[41] After which, the fires began to subside. To make matters worse for the official collapse theory, NIST also found that “the fuel loading in the core areas....was negligible.”[42] It’s easy to understand why all of these facts are downplayed in the NIST summary report. Taken together, they are fatal to NIST’s collapse model, which requires that high temperatures be sustained. Fires that subside after only 15-20 minutes simply cannot weaken enormous steel columns and cause them to buckle. 

 
I searched the NIST report in vain for any acknowledgment that the fire conditions in the laboratory furnace were substantially different from the actual conditions on 9/11. This fact, which is undeniable, calls into question NIST’s conclusion that damaged SFRM insulation was the critical factor. Although NIST took the position that “temperatures and stresses were high in the core area,”[43] on what basis did they reach this conclusion? As I’ve noted, NIST suffered from a persistent lack of information about the actual conditions in the core of the towers. 

 
Surely, it is safe to conclude that the crashed Boeing 767s damaged and/or stripped away a substantial portion of the protective SFRM insulation from the steel beams and trusses in the impact zone. Exactly how much is not knowable. NIST acknowledges in its report that it had no hard evidence about the amount of protective insulation damaged or dislodged during the impacts.[44] Incredibly, however, the agency then assumes that all structural members in the debris path at the time of impact suffered 100% loss of insulation.[45]

 
The only physical evidence NIST presents in its report in support of this conclusion is a series of photos of the exterior of the towers. The photos do show that within the impact zone much of the SFRM foam insulation is indeed missing from the perimeter columns.[46] In places the original anti-rust paint is clearly visible on the exposed columns, indicating that the insulation is gone from these areas. NIST is also probably correct that the loss occurred during the impacts. But it does not follow on this basis that all of the insulation in the impact zone was similarly lost. In fact, not only does the photographic evidence in the report not prove this, the photos show decisively that at least some of the insulation remained in place. NIST even acknowledges this in its discussion of the photos. The report states, for example, that one photo “shows the absence of at least some, if not most SFRM from the center region of the outer web of the column.” Here, “the absence of at least some” of the insulation can only mean that some of it also remained in place. The next passage goes on to describe one column in the same area on which the SFRM was “nearly intact.”[47] In another section the report explicitly mentions that some of the insulation had apparently been treated with a special sealant, which “prevented the loss of SFRM in a great many locations where the SFRM was knocked off both above and below this location.”[48]  In short, NIST flatly contradicts itself regarding the disposition of the SFRM; and this is crucial because it means NIST’s own data fails to support its conclusions. 

 
For the sake of argument, however, let us for the moment ignore this glaring problem and assume that NIST’s estimated total loss of SFRM was correct. As I will now show, even in this worst case scenario there is virtually no chance that the fires on 9/11 weakened the WTC’s core and perimeter columns within the allotted span of time. 

 
A Vast Heat Sink

 
The reason is acknowledged nowhere in the NIST report, but ought to be self-evident. The WTC’s support columns did not exist in isolation. The WTC was no laboratory furnace. The columns in each tower were part of an interconnected steel framework that weighed some 90,000 tons; and because steel is known to be at least a fair conductor of heat, on 9/11 this massive steel superstructure functioned as an enormous energy sink. The total volume of the steel framework was vast compared with the relatively small area of exposed steel, and would have wicked away much of the fire-generated heat. Anyone who has repaired a copper water pipe with a propane torch is familiar with the principle. One must sit and wait patiently for the pipe temperature to rise to the point where the copper finally draws the solder into the fitting. While it is true that copper is several times more conductive than steel, the fact that only three steel samples showed exposure to temperatures above 250ºC indicates that the steel superstructure was indeed behaving as a heat sink. The fires on 9/11 would have taken many hours, in any event, much longer than the relatively brief allotted span of 56/102 minutes, respectively, to slowly raise the temperature of the steel framework as a whole to the point of weakening even a few exposed members. 

 
And there are other problems. Since in a global collapse all of the columns by definition must fail at once, this implies a more or less constant blaze across a wide area. But such was not the case on 9/11. As I’ve already noted, NIST found that the unexpectedly light fuel load in any given area of the WTC was mostly consumed in about 15-20 minutes. At no time on 9/11 did the fires rage through an entire floor of the WTC–––as Thomas Eagar implied in his interview. The fires were not sustained, on the contrary, they were transient.[49] This was especially true in WTC-1. The fires flared up in a given area, reached a maximum intensity within about 10 minutes, then gradually died down as the fire front moved on to consume combustibles in other areas. But notice what this also means: As the fires moved away from the impact zone into areas with little or no damage to the SFRM fireproofing, the heating of the steel columns and trusses in those areas would have been inconsequential. The NIST’s own data showed that, overall, the fires on floor 96–––where the collapse supposedly began–––reached a peak 30-45 minutes after the impact and waned thereafter. Temperatures were actually cooling across most of floor 96, including the core, at the moment of the collapse. But if this is correct, the central piers at that point were not losing strength but regaining it.[50] How, then, did they collapse? Moreover, NIST’s assertion that “temperatures and stresses were high in the core area” is not supported by its finding that the fuel load in the core was negligible.[51] On this point NIST again contradicts itself. For all of these reasons, NIST fails to explain in its report how transient fires weakened WTC-1’s enormous core columns and perimeter columns in the allotted span, triggering a global collapse. 

 
 The Fires in the South Tower

 
NIST determined that the fire behavior in the south tower was substantially different: more continuous rather than transient, at least, on the east side of the building where the remains of Flight 175 supposedly came to rest. This, in addition to more extensive impact damage, NIST informs us, explains why WTC-2 collapsed first, even though it was hit after WTC-1. It is now known, however, that NIST ignored important evidence that calls into question its assertion that fires were gravely weakening the core of WTC-2. An audio-tape released in August 2002 by the Port Authority of New York, which apparently was lost or neglected for more than a year, is the only known recording of firefighters inside the towers. When city fire officials belatedly listened to it they were surprised to discover that two NYC firemen actually reached the impact/fire zone of the south tower about fourteen minutes before it collapsed. The long climb up the stairs was so arduous that most of the NYC firemen, heavily burdened with equipment, were exhausted before they reached the 20th floor. However, these two, Battalion Chief Orlo J. Palmer and Fire Marshall Ronald P. Bucca, were in excellent physical condition. Palmer, reportedly, was a marathon runner. On reaching the 78th floor sky lobby they found many dead or seriously injured people; but no raging inferno. Palmer’s radio exchange with another fireman shows no hint of panic or fear, as the following transcript shows:

 
Battalion Seven Chief (Palmer): "Battalion Seven ... Ladder 15, we've got two isolated pockets of fire. We should be able to knock it down with two lines. Radio that, 78th floor numerous 10-45 Code Ones.

 
Ladder 15: "Chief, what stair you in?"

 
Battalion Seven Chief: "South stairway Adam, South Tower."

 
Ladder 15: "Floor 78?"

 
Battalion Seven Chief: "Ten-four, numerous civilians, we gonna need two engines up here."

 
Battalion Seven Chief: "Tower one. Battalion Seven to Ladder 15."

 
Battalion Seven Chief: "I'm going to need two of your firefighters Adam stairway to knock down two fires. We have a house line stretched we could use some water on it, knock it down, okay."

 
Ladder 15: "Alright ten-four, we're coming up the stairs. We're on 77 now in the B stair, I'll be right to you."

 
Battalion Seven Operations Tower One: "Battalion Seven Operations Tower One to Battalion Nine, need you on floor above 79. We have access stairs going up to 79, kay."

 
Battalion Nine: "Alright, I'm on my way up, Orlo."[52]
 
 
Here, Battalion Chief Palmer calls for more men and water to put out the isolated fires. His expression “10-45 Code Ones” refers to dead bodies, of which apparently there were many. The tape shows that the two firemen were not turned back by heat, smoke, or a wall of flames. They were able to function within the fire zone and were prepared to help the injured and combat the few isolated fires they found. Palmer even mentions that the stairway up to the next level, i.e., floor 79, was passable. Minutes later the building came down on their heads. 

 
NIST knew about this testimony. The NIST report briefly mentions that firemen reached the 78th floor of WTC-2.[53] Inexplicably, however, the matter is simply dropped, as if it had no bearing on the status of the fire in the core. The omission is conspicuous, because, as I’ve stressed, NIST suffered from a persistent lack of information about the dynamic conditions in the interior of the buildings.[54] Here was a real-time eyewitness account by trained professionals who were on the scene. Yet, NIST ignored it. Why? Well, obviously, because their testimony does not support the official story. Curiously, the 9/11 Commission Report also briefly mentions this episode, but, likewise, fails to discuss its possible significance, no doubt, for the same reason.[55]

 
According to NIST, the 78th floor of WTC-2 had fewer combustibles than other floors because it was a sky lobby, and on this basis the report leads us to believe that much more intense fires were raging several floors above the two brave firemen–––fires that did cause fatal weakening of the columns. The problem for NIST, however, is that survivors from these higher floors tell a very different story. As we know, WTC-2 was unlike WTC-1 in that a number of individuals in the south tower did manage to escape the impact zone via stairwell “A,” which luckily remained passable. (In his radio message Orlo Palmer refers to it as “south stairway Adam.”) One of these survivors was Stanley Praimnath, an employee of Fuji Bank who was on the 81st floor when Flight 175 crashed into the south tower. In fact, the wing of the plane reportedly passed within twenty feet from him. Yet, Praimnath escaped without serious burns and in his testimony mentions nothing about a raging inferno.[56] Brian Clark, another survivor, was an executive vice-president of Euro Brokers, based on the 84th floor. As Clark descended the stairs, he heard someone crying out for help. It was Praimnath, who at the time was still trapped on the 81st floor in the rubble. Clark found and freed the man, whereupon, the two escaped together down the stairs. These two survivors are living proof that the official story cannot be right. Both were in the fire zone during and immediately after the impact, when the fires were most intense due to the spilled jet fuel. If the temperatures in the core were 1,000ºC or higher, as NIST would have us believe, the two men would have died within minutes. Yet, both survived, and here is Clark’s description of the fire: "You could see through the wall and the cracks and see flames just, just licking up, not a roaring inferno, just quiet flames licking up and smoke sort of eking through the wall."[57] [my emphasis] Quiet flames. No roaring inferno. It is not surprising that NIST chose to ignore the testimony of these survivors. 

 
I’ve shown that the known accounts of eyewitnesses do not support the official story regarding conditions at the core of WTC-2–––testimonials that NIST likely excluded from consideration for this reason. But what about empirical evidence? Among the steel samples that NIST investigators recovered from WTC-2 were two core columns (C-88a and C-88b) from the impact zone. Actually, they were two different members from the same column (801). The NIST pinpointed their location on floors 80 and 81, several floors above the firemen, very near the path of Flight 175. Both samples had been physically damaged, yet, NIST found no evidence of the kinds of distortion, i.e., buckling, bowing, slumping, or sagging, that would be expected in cases of heat-weakened steel. Furthermore, although the samples came from within the fire zone, NIST was unable to show that the steel had been exposed to high temperatures.[58] This finding is so astonishing it bears repeating: The NIST report presents no physical evidence whatsoever that the fires in the core of WTC-2 were raging infernos. On what, then, does the agency base its conclusion that “Dire structural changes were occurring in the building interior”?[59] The answer, apparently, is the following strange hedge: 

 
“Note that these core columns represent less than 1 percent of the core columns on floors involved with fire and cannot be considered representative of any other core columns.”[60] 

 
In other words, we are supposed to accept NIST’s theory about the fire solely on the basis of its opinion that a larger sampling of columns would have enabled NIST to prove its case. But this is hogwash! It simply is not the way science is done. Indeed, the paucity of evidence, if anything, calls into question NIST’s earlier assertion that its sampling was adequate. 

 
What is even more amazing is that NIST’s own computer simulations of the WTC fires tend to bear this out. Any curious reader who invests the time to review the relevant NIST document (i.e., CSTAR 1-5) will find page after page of color-coded graphic diagrams of these simulations, one set for each floor in the fire zone. Nearly all of them show that the core remained cool throughout the fires. The burden of proof was on NIST to demonstrate how the fires weakened the core columns in the allotted time; and the only reasonable conclusion one can draw is that the agency fails to present even a minimal case. This also means, of course, that NIST likewise fails to explain the global collapse. 

 
For the sake of argument, however, in order to show just how weak the official collapse model is, let us assume that the fires did burn hot enough and were sustained long enough, and caused numerous exposed columns in the impact zone to lose roughly half of their strength. As I will now show, even if this did occur it still fails to account for the global collapse of either tower.

 
The Issue of Reserve Capacity

 
 As the NIST report states, 

 
“both towers had considerable reserve capacity. This was confirmed by analysis of the post-impact vibration of WTC-2, the more severely damaged building, where the damaged tower oscillated at a period nearly equal to the first mode period calculated for the undamaged structure.” [61] [my emphasis]
 
 
The above passage informs us that WTC-2 gave no sign of instability after the impact of Flight 175. Unfortunately, although NIST’s summary report provides a wealth of information about how the World Trade Center was constructed it fails to clarify the important matter of the WTC’s “considerable reserve capacity.” At any rate, I scoured the report in vain for a clear discussion of the issue. In frustration, I finally called NIST for assistance and was guided to several of the project reports and supplementary documents. I also consulted with Gary Nichols, an expert at the International Code Council (ICC), and with Ron Hamburger, a leading structural engineer. These conversations were an education. I learned that estimating the overall reserve capacity of a steel structure is by no means a simple matter. Numerous factors are involved. Moreover, there are different ways to approach the problem. 

 
Perhaps the simplest measure of reserve capacity are the standards for the material components of a building. In the late 1960s when the WTC was constructed the applicable standard was the New York City Building Code, which required a builder to execute computations for the various structural members to show that they met the specified requirements. However, the code also allowed for actual testing of members in the event that computations were impractical. The testing standards applicable in 1968 give a reasonable idea of the required level of reserve strength in the steel columns and other materials used in the WTC.  For example, in the most stringent test a steel member had to withstand 250% of the design load, plus half again its own weight, for a period of a week, without collapse.[62]
 
 

 
Factor of Safety

 
Another widely used measure of reserve capacity is the so called “factor of safety.” This varies for different structural elements, but for steel columns and beams typically ranges from 1.75 - 2.0.[63]  The NIST report actually breaks down this more general figure into two separate and slightly different measurements for stress: yielding strength (1.67) and buckling (1.92).[64] For our purposes, however, the more general figure is adequate. So, for example, a steel column with a factor of safety of 1.75 must support 1.75 times the anticipated design load before it begins to incur damage. While this value is typical of steel beams in general, the actual reserve strength of the steel columns in the WTC was higher. When NIST crunched the numbers for the 47 core columns of WTC-1 (in the impact zone, between the 93rd and 98th floors) it calculated that the factor of safety ranged from 1.6 to 2.8, the mean value being 2.1.[65] This means that the average core column in the impact zone of WTC-1 could support more than twice its design load before reaching the yield strength, i.e., the point where damage may begin to occur. My grateful thanks to the NIST investigative team for helping me locate these numbers, which were buried in the report.

 
It is important to realize that the factor of safety is not a threshold for collapse, but a value beyond which permanent damage may begin to occur. As the NIST report admits, even “after reaching the yield strength, structural steel components continue to possess considerable reserve capacity.”[66] This is why steel beams and columns typically do not fail in sudden fashion. The loss of strength is gradual. No doubt, this helps to explain why, although fires have ravaged many steel frame buildings over history, none had ever collapsed–––until 9/11–––nor has any since. What all of this means, of course, is that even in the most improbable worst case, in which many or all WTC core columns lost half of their strength, there was still sufficient reserve capacity to support the building.

 
The Perimeter Wall

 
With regard to the WTC’s perimeter columns, the factor of safety fluctuated from day to day and even from hour to hour, because, in addition to supporting 47% of the WTC’s gravity load, the perimeter wall also had to withstand the lateral force of the wind, which is highly variable given the whims of Mother Nature. A single face of the WTC presented an enormous “sail” to the elements, for which reason John Skilling vastly overbuilt this part of the structure. According to the NIST report, the outer wall’s factor of safety against wind shear on 9/11 was extraordinary, i.e., in the 10-11 range.[67] Why so high? The answer is simple: On the day of the attack there was essentially no wind, only a slight breeze.[68] For this same reason nearly all of the perimeter wall’s design capacity was available to help support the gravity load. As the NIST report states, “On September 11, 2001 the wind loads were minimal, thus providing significantly more reserve for the exterior walls.”[69] When NIST crunched the numbers for a representative perimeter column in WTC-1 (column 151, between the 93rd and 98th floors), they arrived at a factor of safety of 5.7.[70] Assuming this average figure is a typical value we arrive at a reasonable estimate of the perimeter wall’s amazing reserve capacity. Even if we subtract those columns severed/damaged by the impact of Flight 175, and the lost capacity due to the alleged (but unproven) buckling along the eastern perimeter wall, there was still a wide margin of safety, more than enough by several times over to support the outer wall’s share of the gravity load, with plenty to spare.[71]
  
 
The WTC’s tremendous reserve capacity was no secret. In 1964, four years before the start of construction, an article about the planned WTC appeared in the Engineering News-Record. The article declared that “live loads on these [perimeter] columns can be increased m
 
 
 

   
Fire!!!

"NIST’s final report stated that of the steel available to it for examination, “only three columns had evidence that the steel reached temperatures above 250 degrees Celsius” (482 degrees Fahrenheit). The self-cleaning ovens in our home kitchens reach temperatures higher than this, and the ovens do not melt or deform."

This is from an article by Paul Craig Roberts which you can read here: 911northwoods 

Do you understand that? 3 columns!! That is supposed to explain the collapse of a 110 story steel framed building. Sorry, nobody with a brain buys that weak explanation.

 

Speaking of fire...

Right now there is a fire burning in a 6 story office building in Houston. It has been reported that the top 2 floors are engulfed in flames. Damn, 2 out of 6 floors engulfed! I hope it doesn't collapse(said in a sarcastic tone). 

 

 

 

 
 
   
 

Dead on Arrival

I haven't posted anything for a while. I really hadn't seen anything worth posting. If you are familiar with the arguments of 9/11 being an inside job then this report probably isn't anything new. However, if you are new to 9/11 research then this could be a great resource. This report is very long but very important...


The NIST 9/11 Report on the WTC Collapse

By Mark H. Gaffney

Note to the reader: The following is a critique of the National Institute for Standards and Technology (NIST) report on the World Trade Center (WTC) collapse. The 43 volume NIST report was the result of a 3 year investigation, and was released in September 2005. It remains the official US government explanation for why the WTC collapsed on 9/11. As you are about to discover, the report itself collapses under scrutiny. There is no doubt that the NIST investigation was politically controlled by limiting its scope, thereby making the truth unobtainable. This is one way to neuter an investigation.

12/21/06 "Information Clearing Hous" -- -- Fires raged at ground zero for many weeks after 9/11. In fact, it was not until December 19, 2001 that the NYC fire marshall declared the fires extinguished.
The fires burned long into the cleanup. The removal of steel beams and debris from the top of the pile allowed oxygen to reach the fires smoldering below. As a result, the flames often flared up, hampering workers on site. Joel Meyerowitz, a photographer, made note of this in his 2006 retrospective book, Aftermath. Armed with his trusty camera Meyerowitz roamed ground zero for months following the attack. Police repeatedly ejected him, but he kept returning in order to document what had happened. Eventually Meyerowitz amassed an impressive photographic record. In his fine book he remarks that the ground in places was so hot it melted the workmen’s rubber boots.

But Meyerowitz was hardly the first to comment on the pile’s incredible residual heat. The first accounts of molten steel came just hours after the attack: from the search and rescue teams who were among the first on the scene. Sarah Atlas, a member of New Jersey Task Force One Search and Rescue, was one of these emergency responders. Sarah reported seeing molten steel in the pile even as she searched in vain for survivors.[1]

Many have denied the existence of molten steel at ground zero. But there are too many eyewitness accounts to dismiss, including the testimony of engineers, city officials and other competent professionals who toured the ruin. One of these, Dr Keith Eaton, Chief Executive of the London-based Institution of Structural Engineers, later wrote in The Structural Engineer about what he had seen, namely: “molten metal which was still red-hot weeks after the event,” as well as “four-inch thick steel plates sheered and bent in the disaster.”[2]

A similar account came from Leslie E. Robertson, an engineer who helped design the WTC. He is currently a partner at Leslie E. Robertson Associates, a structural consulting firm that was under contract to the WTC at the time of the tragedy. In a keynote address Robertson reportedly told the Structural Engineers Association of Utah that: “...as of 21 days after the attack the fires were still burning and molten steel still running.”[3] Public health officials/experts also toured the scene of destruction. Alison Geyh Ph.D., an Assistant Professor of Environmental Health at Johns Hopkins, was with one of these teams. She wrote that “In some pockets now being uncovered they are finding molten steel.”[4] The fact was even reported to the 9/11 Commission by Kenneth Holden, Commissioner of the city of New York. He told the panel about seeing “molten metal” during a walkthrough.[5]

The evidence accumulated even as the cleanup progressed. Work crews removing the mountain of debris, piece by piece, discovered pools of molten steel beneath the pile, where the towers had stood. One pool was found at the bottom of the elevator shafts. Some of the pools were not found until 3, 4, even 5 weeks after 9/11.

Contractors working on site confirmed these discoveries. Such as Peter Tully, president of Tully Construction of Flushing New York, who was one of four contractors engaged by New York City to handle the cleanup. During an August 2002 interview Tully told the American Free Press that indeed workmen had seen the molten pools.[6] The same interview included a statement by Mark Loizeaux, president of Controlled Demolition, Inc., who, years before, ramrodded the cleanup of the bombed Federal Building in Oklahoma City. Loizeaux was called in by Tully to draft the cleanup plan for the WTC site. Loizeaux said, “Yes, hot spots of molten steel were seen in the basements.” Molten steel was also found under WTC 7.

These pools of molten metal have never been explained. Loizeaux told the American Free Press that the continuing fires were fueled by “paper, carpet and other combustibles packed down the elevator shafts by the tower floors as they ‘pancaked’ into the basement.” Manuel Garcia, a physicist, has suggested that cars left in parking garages under the WTC contained gasoline that may have fueled the fires.[7] Both are probably correct. But none of these fires were hot enough to melt steel. Indeed, none of the combustibles in the wreckage burned anywhere near the melting point of construction grade steel beams (2800 °F). As noted, the smoldering fires for the most part were oxygen-starved.

The persistence of molten steel under the WTC for many weeks is extraordinary–––and anomalous. Evidently, the hot spots under the wreckage were not in the least fazed by heavy rain on September 14-15, nor by the millions of gallons of water that firemen and cleanup crews sprayed on the smoking ruins. Five days after the attack the US Geological Survey (USGS) found dozens of “hot spots” in the wreckage via remote sensing, i.e., an infrared spectrometer (AVIRIS). The two hottest spots were under WTC 2 and WTC 7. The USGS recorded surface temperatures as high as 747°C (1376°F)).[8] The molten pools below the pile must have been at least twice as hot––––hot enough to evaporate rain and the water sprayed on the pile, long before it reached the bottom.

The Official Reports

In its official report the 9/11 Commission never once mentions the molten pools–––despite the testimony of the New York City commissioner.

In its 43-volume report about the WTC collapse released in September 2005, the National Institute of Standards and Technology (NIST) does indeed mention the molten pools, but only in passing, to dismiss them. The NIST report not only fails to identify the energy source that melted steel beams and piers under the WTC, it states categorically that NIST inspectors found no evidence of any molten steel at ground zero–––a dismissal that is directly contradicted by the eyewitness accounts of the emergency responders, engineers, officials, and health experts already cited, not to mention the lead contractors who accomplished the cleanup.[9] After brushing aside the issue as irrelevant to the WTC collapse, the NIST report then suggests that:

“Under certain circumstances it is conceivable for some of the steel in the wreckage to have melted after the buildings collapsed. Any molten steel in the wreckage was more likely due to the high temperature resulting from long exposure to combustion within the pile than to short exposure to fires or explosions while the buildings were standing.” [my emphasis] [10]

The NIST never clarifies what the “certain circumstances” might be that produced molten steel after the collapse. Its statement about “long exposure to combustion” is absurd on its face, given that there was no energy source in the pile of wreckage remotely capable of melting steel. In fact, the NIST’s above statement is an affront to our intelligence, since the hot spots identified by the US Geological Survey immediately after 9/11 and the molten pools were surely one and the same. There is no way to avoid the conclusion that the molten materials under the wreckage, as well as the smoldering fires, were a residual product of whatever caused the collapse of the WTC. Something on September 11, 2001 burned hot enough to melt steel in the basement of both towers. But such a deduction is too simple, evidently, or too provocative for the NIST, which made a decision not to go there.

When asked about what caused the molten pools Peter Tully suggested that perhaps jet fuel was responsible. But on this point, at least, the NIST report is surely correct. It’s easy to show that jet fuel was not the causative agent. There were reports that burning jet fuel leaked into the WTC elevators moments after the first impact. A descending fireball possibly caused explosions many floors below. Witnesses saw critically burned people emerging from elevators. Something ripped through the WTC 1 concourse lobby at about the time of the impact, blowing out windows and crumpling steel doors like they were paper. The same blast even knocked marble slabs off the walls in the lobby. Custodians also heard explosions in the WTC 1 basement. A machine shop was wrecked, as well as a car garage.[11]

But as serious as these explosions and fires were, jet fuel simply does not burn with sufficient energy to melt steel–––not even close. Many of the early reports by the US and world press erred in this respect. Indeed, in the emotional aftermath of the 9/11 attack the press often mangled the science as badly as the twisted steel beams of the WTC. One report posted by the BBC on September 13, 2001 quoted experts who stated matter-of-factly that the burning jet fuel actually melted the central columns, leading to the collapse.[12] Another report on The History Channel, The Anatomy of September 11th, claimed that the inferno turned the steel piers in in the WTC to “licorice.” A 2002 PBS NOVA special “Why the Towers Fell” showcased a similar theory, and suggested that the fires reached 2000°F, which caused the steel columns to lose 80% of their strength.[13]

Even trained professionals jumped on the bandwagon–––and got it wrong. The day after the attack the Sunday Times interviewed Hyman Brown, a civil engineering professor at the University of Colorado: “Steel melts,” Brown said, “90,850 liters of aviation fluid melted the steel. Nothing is designed....to withstand that fire.” Years before, Brown had been involved in the construction of the WTC as a project engineer.[14] (He was later shown to be wrong about the amount of jet fuel. The NIST determined that the planes actually carried no more than 10,000 gallons–––about 40,000 liters).

The same day NewScientist.com asserted that “raging fires melted the supporting steel struts.”[15] On September 13, 2001 BBC radio interviewed Chris Wise, an engineer who explained that...

"It was the fire that killed the buildings. There’s nothing on earth that could survive those temperatures with that amount of fuel burning. The columns would have melted, the floors would have melted, and eventually they would have collapsed one on top of the other."[16]

Elmer Obermeyer, the president of an Ohio engineering firm, also endorsed the meltdown theory in a story in the Cincinnati Business Courier. The paper noted that Obermeyer was a “guru in his field.”[17] In October 2001 Scientific American.com posted an article summarizing the results of a 9/11 panel of MIT experts, one of whom, Eduardo Kausel, stated “that the intense heat softened or melted the structural elements—–floor trusses and columns–—so that they became like chewing gum, and that was enough to trigger the collapse.[18]

This is but a small sampling of many such reports that appeared in those first days. All of them were wrong. As Frank Gayle, one of the NIST’s lead scientists, later pointed out: “Your gut reaction would be [that] the jet fuel is what made the [WTC] fire so very intense. A lot of people figured that’s what melted the steel. Indeed, it did not, the steel did not melt.”[19] Gayle was seconded by Thomas Eagar, a professor of materials engineering at MIT:

"The Fire is the most misunderstood part of the WTC collapse. Even today the media report (and many scientists believe) that the steel melted. It is argued that the jet fuel burns very hot, especially with so much fuel present. This is not true....The temperatures of the fire at the WTC were not unusual, and it was most definitely not capable of melting steel."[20]

When trained professionals get it wrong we should not be surprised by the mistakes of journalists, few of whom are trained in physics. The fact is that jet fuel, which is essentially kerosene, will not burn in air in excess of about 1,000°C (1,832°F)–––nowhere near the 2,800°F melting point of steel. Even this 1,000°C upper limit is very difficult to achieve, since, as Thomas Eagar pointed out, it requires the optimal mixing of fuel with oxygen during combustion, which can only be achieved in a laboratory. In fact, the clouds of black smoke that poured out of the twin towers on 9/11 were an obvious sign that the WTC fire burned at much lower temperatures, probably around 650°C (1,202°F) range, or even lower. This was due to the inefficient mixing of oxygen. It’s why most building fires burn no hotter than around 500-650°C. (932 -1,202°F)

To date, no one, including the NIST, has identified an energy source in the WTC–––or in the Boeing 767s–––capable of melting steel.

The NIST Report

Since the primary stated objective of the NIST 9/11 investigation was to determine the cause of the WTC collapse, the NIST should have conducted a forensic examination of the full spectrum of evidence.[21] Ground zero was a crime scene, was it not? Yes, and because many credible eyewitnesses, including firemen who were on duty that fateful day, reported that they heard and/or saw explosions, the NIST should have investigated this without bias.[22] It should have viewed their testimony as hard evidence: a starting point in its investigation. Instead, the NIST did a gloss. It posted a statement on its web site asserting that it had considered a number of hypotheses, including a planned demolition, but had found no corroborating evidence.[23] This disclaimer was no more than a last-minute attempt to deflect criticism, since a close reading of the NIST report shows that the agency never entertained other alternatives. It certainly never investigated the eyewitness accounts of explosions.

The NIST report assumes, start to finish, that the Boeing 767s were responsible for the collapse of the twin towers. The agency took it for granted that the impacts set in motion a chain of events leading to catastrophic structural failure. The assumption is even stated explicitly in the Executive Summary:

“The tragic consequences of the September 11, 2001 attacks were directly attributable to the fact that terrorists flew large jet-fuel laden commercial airliners into the WTC towers. Buildings for use by the general population are not designed to withstand attacks of such severity; building codes do not require building designs to consider aircraft impact.”[24]

The 43 volume NIST report confines itself to the sequence of events from the first plane impacts to the onset of collapse; and is governed throughout by ipso facto reasoning. Because the agency never entertained the possibility of a planned demolition, it never bothered to look for evidence of same. For example, it never tested steel samples recovered from ground zero for telltale traces of explosives. These omissions were irresponsible and smack of political interference, since in addition to the eyewitness accounts two scientific papers, one published in 2001, and another by FEMA in May 2002, had already detected sulfur residues on samples of WTC steel.[25] As Dr. Steven Jones, a physics professor at BYU, has pointed out, sulfidation of steel can be an indicator of the use of thermate (or other closely related compounds) developed by the military and commonly used to cut steel in demolitions work.[26] The possibility needed to be checked, if only to rule it out; but the agency, again, chose not to go there.

Let us now examine the NIST report in detail.

Why the WTC Survived the 767 Impacts

Everyone, including the NIST, agrees that the twin towers survived the initial Boeing 767 impacts on September 11, 2001–––despite serious damage. The buildings survived because the WTC was hugely overbuilt: redundant by design. The towers simply transferred the load from the severed/damaged members to other undamaged columns.

Upon its completion in 1970 the World Trade Center was not only the world’s tallest twin-skyscraper (1,368 feet), it was also a state-of-the-art achievement of modern construction.[27] Although the WTC’s soaring lines gave the impression of a relatively light frame, in fact, the towers were extremely rugged, engineered to withstand hurricane-force winds and to survive a direct hit by a Boeing 707, the largest commercial jetliner of the day. In a 1993 interview the WTC’s principal structural engineer, John Skilling, stated that prior to construction he performed an impact analysis of a 600 mph Boeing 707 impact, and concluded “that the building structure would still be there.”[28] The architectural firm that worked with Skilling described his 1,200 page structural analysis as “the most complete and detailed ever made for any building structure.”[29] Frank A. Demartini, onsite manager during the construction of the WTC, seconded this view during a January 25, 2001 interview, in which he noted that the study involved “a fully loaded 707.” Demartini even declared that “the building probably could sustain multiple impacts of jetliners because this structure is like the mosquito netting on your screen door, this intense grid, and the jet plane is just a pencil puncturing that screen netting.”[30] Demartini kept an office in the North Tower and was last seen on 9/11 assisting evacuees on the 78th floor.[31]

The original WTC design, the work of architect Minoru Yamasaki, was one of the first architectural plans to call for open space within a steel-frame building. This meant doing away with the forest of columns so typical of the steel high-rise buildings of former years. Chief engineer Skilling achieved the objective with a double support system: a dense array of 236 columns around the perimeter, and a network of 47 massive piers at the core. The creation of large expanses of unobstructed floor space within the WTC was a novel idea in the 1960s, but is commonplace today.[32]

The weight of each building was distributed about equally between the two sets of columns. The outer wall shielded the building from high winds, and was reinforced with broad steel plates known as “spandrels,” which girdled the building, like ribs, at every floor. The core contained the elevators, stairwells, and utility shafts. Both sets of columns were joined together by an innovative system of lightweight steel trusses. Each story was supported by a truss assembly covered with a corrugated steel deck–––the bed for a poured slab of lightweight concrete. Probably Skilling’s greatest innovation was to extend the truss diagonals up into the concrete floor, which added stiffness and strength. Each truss assembly/concrete floor behaved as a single unit.

Prefabrication and the overall modular design were other innovations that allowed for speedy construction–––and kept costs down. The advent of new high-strength steels made it all possible. In fact, the WTC had tremendous reserve capacity. An early article about the project in the Engineering News-Record declared that “live loads on these [perimeter] columns can be increased more than 2,000 percent before failure occurs.”[33]

After a three-year investigation the NIST concluded that the World Trade Center would have survived on 9/11 if the impacts had not dislodged the buildings’ protective fireproofing–––installed at the time of construction to protect the steel columns from fire-generated heat. Construction-grade steel begins to lose its tensile strength at 425°C (~800°F), and is only about half as strong at 650°C (1,202°F). The lightweight truss assemblies were especially vulnerable, since they consisted of rather thin steel members. During construction they were coated with spray-applied insulation. The much larger steel piers and columns had a fire-barrier of gypsum wallboard.

NIST’s Official Explanation

The NIST concluded that the impact of the jetliners damaged or dislodged 100% of the protective insulation within the impact zone, while also spilling many thousands of gallons of jet fuel over multiple floors. The resulting 800-1,000°C (1,440-1,800°F ) blaze seriously weakened the now-exposed steel trusses. The trusses and floors sagged–––they argued–––which pulled the perimeter columns inward, causing them to buckle. The fires also weakened the central piers. The combination of these effects destabilized the structures and at a critical point the towers simply collapsed. The NIST concluded that the WTC would have survived the fires if the Boeing 767 impacts had not dislodged/damaged the fireproofing material, which, therefore, according to the NIST, was the critical factor on 9/11.

There are a number of serious problems, however, with this official narrative. In the first place, it is sharply at odds with the video record, which plainly shows that during each collapse perimeter columns and other structural members didn’t simply fall to the ground. In many cases they were ejected up and out of the disintegrating structure at nearly a 45 degree angle: a cascade that hurled steel beams weighing 20 tons or more as much as 600 feet from the base of the buildings. One remarkable photo of ground zero taken from above shows that entire sections of WTC 1’s western perimeter wall were thrown 500+ feet toward the Winter Garden.[34] Could a gravitational collapse do this?

Pulverization

Photos of the mountain of wreckage taken by Joel Meyerowitz and others also show very few, if any, large chunks of concrete. The rubble pile almost exclusively consisted of twisted steel beams, pipes, aluminum, etc. Concrete was conspicuous in its absence. This is remarkable when you consider that the 500,000 ton towers were made up largely of concrete. Each floor of the 110-story WTC, roughly one acre in size, consisted of a 4-inch thick slab of poured concrete on a deck of 22-gauge steel. During the collapse something–––some force–––pulverized nearly all of this concrete into fine dust. Many have attributed this to the brute hammer of gravity, but the videos clearly dispute this. The buildings weren’t pulverized as they hit the ground, but rather, in midair as the buildings disintegrated. Much of the dust settled a foot or more deep on the 16-acre WTC site. The rest was deposited across lower Manhattan. Nor was this pulverization limited to concrete. Many other materials also disappeared without a trace on 9/11; such as office furniture and thousands of computers, not to mention the many victims who died in the collapse. It’s a fact that less than 300 corpses were recovered in the wreckage. Yet, strangely, many months later, during the demolition of the Deutsch Bank–––badly damaged in the 9/11 attack–––workers found more than 700 body parts, e.g., slivers of bone, on the roof and within the doomed structure.[35] The question is: why? This bizarre report remains a mystery.

The videos of the collapse also reveal another anomaly, one that I find personally disturbing. The towers did not pancake in the usual fashion of concrete buildings. When large buildings drop during powerful earthquakes each story tends to fall more or less intact upon the floors beneath. The building itself serves to brake the fall from above. Photographs taken after earthquakes typically show a succession of concrete slabs piled one on top of another, each plainly discernible in the rubble. But nothing like this happened on 9/11. The collapse of WTC 1 and WTC 2 were nearly a free-fall. If the towers had pancaked from above the inertial mass of the lower floors would have resisted and slowed the fall considerably–––even arrested it. But this didn’t happen. The towers plummeted as if there were no resistance whatsoever. From start to finish they fell in only about 12 seconds, just 2 seconds longer than the time for a billiard ball to drop from the WTC roof to the plaza below. The question is why?

The NIST investigation failed to address any of these anomalies. In fact, it didn’t even try. The NIST sidestepped the ejection of material, the vast pulverization of concrete, the many testimonials and other evidence of explosions, and the near-free fall by limiting its investigation to the sequence of events from the Boeing 767 impacts to the onset of the collapse. Incredibly, the NIST chose not to examine the collapse itself. The report makes reference to the “global collapse” of the WTC, but we never learn what this means because the NIST report never tells us. Once again, the agency decided not to go there. Evidently we are supposed to assume that gravity alone was responsible. But could gravity transform enormous slabs of concrete, hundreds of thousands of tons of material, into fine dust, in midair? Extremely doubtful. The NIST’s decision not to investigate these important questions add up to more grave omissions.

But we haven’t yet examined the NIST report itself. Let’s do that, now.

The Special Projects

The NIST investigation incorporated eight separate projects, all of which, together, produced 42 volumes of supporting documentation; all told, some 10,000 pages. The projects included an impact analysis, metallurgical studies, a reconstruction of the fires, and a computer model of the probable sequence of events leading up to collapse of each tower. Some of the agency’s investigative work was of excellent quality–––some wasn’t–––but very little of it lends credence to the NIST’s final, and official, explanation of the cause of the WTC collapse.

One of the most serious and persistent problems NIST investigators faced was the admitted lack of information about conditions at the core of the towers.[36] To be sure, thousands of photographs and hundreds of hours of videotape made it possible to study in detail the damage to the WTC exterior, and to gain a reasonable understanding about conditions in the outer offices. Fires were often visible through the windows, despite dense smoke, and sagging floors and other structural damage was discernible through gaping holes in the damaged exterior. However, as the NIST report states, “Fires deeper than a few meters inside the building could not be seen because of the smoke obscuration [sic] and the steep viewing angle of nearly all the photographs.”[37] Thus, except for steel samples gathered after the fact the NIST had almost no other information about the dynamic conditions at the core of the WTC on 9/11.[38]

The agency sought to overcome this shortfall of information with computer simulations. This was problematic from the outset, since computer models are no better than the quality of input and the accuracy of the programmer’s assumptions. As architect and critic Eric Douglas points out in his 2006 analysis of the NIST report: “a fundamental problem with....computer simulation is the overwhelming temptation to manipulate the input data until one achieves the desired results.”[39] Did the NIST investigators fall prey to this insidious tendency? And did this lead them to overestimate the impact damage to the WTC interior? Let us now consider this question.

NIST’s Global Impact/Collapse Analyses

In one of its most important projects (NCSTAR 1-2), NIST scientists developed a global impact analysis: to estimate the structural damage to the WTC caused by the Boeing 767s. In this study the NIST considered three different scenarios. These ranged from less damage to extreme damage, with a moderate alternative (described as “the base”) in the middle. As it happened, all three scenarios accurately predicted the impact damage to the WTC exterior at the point of entry; although with regard to WTC 1 the moderate case was a slightly better match.[40] The three differed greatly, however, in predicting the number of severed columns at the WTC core, a datum obviously of great importance. In the case of WTC 1 the lesser alternative predicted only one severed core column, the moderate alternative predicted three, while the extreme alternative predicted five to six. In the case of WTC 2 the disparity was even greater: The lesser alternative predicted three severed columns, the moderate five, and the extreme case no less than ten.[41]

Although the NIST never satisfactorily resolved these differences, it immediately threw out the less severe alternatives, citing two reasons in the summary report: first, because they failed to predict observable damage to the far exterior walls; and second, because they did not lead to a global collapse.[42]

On 9/11 the first tower sustained visible damage to its opposite. i.e., south wall, caused by an errant landing gear and by a piece of the fuselage, which were later recovered from below. Also, at the time of the second impact a jet engine was seen exiting WTC 2’s opposite wall at high speed, after passing straight through the building. It was later found on Murray Street, several blocks northeast of the WTC. In its summary report the NIST leads us to believe that it used the observable damage to the far walls caused by these ejected jet plane parts to validate its simulations. Yet, in one of its supplementary documents the NIST admits that “because of [computer] model size constraints, the panels on the south side of WTC 1 were modeled with a coarse resolution...[and for this reason] The model....underestimates the damage to the tower on this face.”[43] But–––notice–––this means that none of the alternatives accurately predicted the exit damage.[44]

This admission, deeply buried in the 43 volume report, is fatal to the NIST’s first rationale for rejecting the lesser alternative, since it was no less accurate than the moderate and extreme cases. (Or, put differently: It was no more inaccurate.) Which, of course, means that the NIST rejected the lesser alternative for only one reason: because it failed to predict a global collapse. The simulations for WTC 2 suffered from the same modeling defect. As the supplementary documentation states, “None of the three WTC 2 global impact simulations resulted in a large engine fragment exiting the tower.”[45] Yet, here again, the NIST rejected the lesser alternative. We can thank researcher Eric Douglas for digging deeper than the summary report. Otherwise, this flaw, tantamount to the devil lurking in the fine print, might never have come to light.

But the NIST was not deterred by its own biased reasoning. Later, it also tossed out the moderate (base) alternatives, ultimately adopting the most extreme scenarios in its subsequent global collapse analysis–––even though, as noted, the moderate alternatives were no less accurate, from a predictive standpoint, than the extreme cases. In fact, with regard to predicting the entry damage to WTC 1, as noted, the moderate alternative was actually a better match. The NIST report offers no scientific rationale for this decision, only the pithy comment that the moderate alternatives “were discarded after the structural response analysis of major subsystems were compared with observed events.”[46] Here, of course, “observed events” refers to the ultimate collapse of the tower. The NIST, though oblique, is at least more forthright than in the case of the lesser alternatives. Things get worse.

As it happened, even the extreme alternatives required further tinkering to be acceptable. The report informs us that “Complete sets of simulations were then performed for cases B and D [the extreme alternatives]. To the extent that the simulations deviated from the photographic evidence or eyewitness reports, the investigators adjusted the input, but only within the range of physical reality.” [my emphasis][47] In other words, NIST scientists worked backwards from the collapse, tweaking the extreme alternatives until their computer model spat out the desired result consistent with their assumption, which never wavered, that the 767 impacts ultimately were at the root of everything on 9/11. Of course, the NIST report never tells us what the “additional inputs” were.

That the NIST’s impact study and subsequent global collapse analysis were biased, hence, unscientific, ought to be obvious. But I will go even further: The impact simulations were very nearly a waste of time, since the NIST had almost no information about the actual conditions at the WTC core. Had the computer model been robust enough to properly characterize the far walls, things might have been very different. In that case investigators could have used the observable damage to the exterior of those walls to discriminate between the three alternatives, hence to select the best choice, validating the model. As it was, the NIST had no sound basis for rejecting the lesser and moderate impact alternatives. Both were at least as plausible as the extreme alternative. Why were they not given equal weight? The reason is obvious: That would have compelled NIST investigators to entertain the unthinkable, i.e., the possibility that some other causative agent was responsible for the WTC collapse. Still, one has to admire, in a perverse sort of way, the NIST’s triumph of circular reasoning.

The Metallurgical Studies

The NIST’s metallurgical and fire studies were among the most important projects, and involved testing 236 samples of steel columns, panels, trusses, and other smaller parts recovered from ground zero. Thanks to the original labeling system used during the construction of the WTC, the NIST was able in many cases to identify individual steel members, and thus to determine their exact locations in the WTC. As it happened, some of the samples were from the impact zones and fire-damaged areas.[48] The collection represented only 0.25 - 0.5 % of the 200,000 total tons of structural steel used the two towers. But the NIST believed it had enough samples to determine the quality of the steel and evaluate its performance on 9/11.[49]

The NIST’s findings decisively refuted the pancake theory of collapse that had been widely reported in the media. According to this theory the WTC collapse on 9/11 was due to failure of the WTC truss assemblies. A number of vocal experts had claimed that the weak link was the point of attachment: where the trusses connected with the inner and outer columns. These junctions, often referred to as angle-clips, were made of relatively lightweight steel and were secured by steel bolts. During a 2002 NOVA special–––before the NIST ran its metallurgical/fire tests–––Thomas Eagar, the MIT engineer already cited, summed up the view of many about how and why the trusses failed on 9/11:

"...the steel had plenty of strength, until it reached temperatures of 1,100º to 1,300ºF. In this range, the steel started losing a lot of strength, and the bending became greater. Eventually the steel lost 80 percent of its strength, because of this fire that consumed the whole floor....then you got this domino effect. Once you started to get angle-clips to fail in one area, it put extra load on other angle-clips, and then it unzipped around the building on that floor in a matter of seconds. If you look at the whole structure, they are the smallest piece of steel. As everything begins to distort, the smallest piece is going to become the weak link in the chain. They were plenty strong for holding up one truss, but when you lost several trusses, the trusses adjacent to those had to hold two or three times what they were expected to hold."[50]

Eagar’s collapse model sounded plausible enough–––but the NIST investigation didn’t bear it out.

Because the NIST did not have the necessary facilities, it contracted Underwriter Laboratories to conduct a series of fire endurance tests on trusses like those in the WTC. (The recovered truss samples were too badly deformed during the collapse to test them directly, so NIST fabricated new trusses identical in design.) The purpose of the tests was to establish a baseline, and the results were surprising. Not one of the truss assemblies failed during a series of four tests, not even the truss sprayed with the minimum amount of fireproofing. “The floors continued to support the full design load without collapse for over two hours.”[51] The investigative team cautiously noted that the exposure of the floor systems to fire on 9/11 was “substantially different” than the conditions in the test furnaces, which was true enough. Yet, the team noted that “this type of assembly was capable of sustaining a large gravity load without collapsing for a substantial period of time relative to the duration of the fires in any given location on September 11.”[52] The UL tests not only laid to rest the theory that the trusses were the cause of the collapse on 9/11, if anything, the tests demonstrated the fundamental soundness of the WTC truss design.

Another finding: The WTC steel turned out to be significantly stronger than expected. Tests showed that the yield strengths of 87% of the perimeter/core columns, and all of the floor trusses samples, exceeded the original specifications by as much as 20%. “The yield strengths of many of the steels in the floor trusses were above 50 ksi, even when specifications required 36 ksi.”[53] (1 ksi = 1,000 lb/per square inch) The NIST performed similar tests on a number of recovered bolts, and found that these too were “much stronger than expected, based on reports from the contemporaneous literature.”[54] Notice, none of these findings support the NIST’s official explanation for the WTC collapse. On the contrary.

The Fire Tests:
Core Weakening?

Another series of tests sought to address the alleged weakening of the WTC support columns. During a first-run investigators placed an uninsulated steel column in a 2,012ºF (1,100ºC) furnace and measured the rise in its surface temperature. Notice, this laboratory furnace was significantly hotter than the fires on 9/11 caused by jet fuel or any other combustible in the WTC. The column reached 600ºC in just 13 minutes, the temperature range where significant loss of strength occurs. When the test was repeated again with an insulated column, the steel did not reach 600ºC even after ten hours. The NIST concluded that “the fires in WTC 1 and WTC 2 would not be able to significantly weaken the insulated....columns within the 102 minutes and 56 minutes, respectively, after impact and prior to collapse.”[55]

The NIST interpreted these results as validating its favored hypothesis that the critical factor on 9/11 leading to the global failure of the WTC’s support columns was the damage to the fireproofing insulation caused by the Boeing 767 impacts. But was this an unwarranted leap? It certainly was not supported by the NIST’s metallurgical analyses, which showed that not even one of the 236 steel samples, including those from the impact areas and fire-damaged floors, showed evidence of exposure to temperatures in excess of 1,110ºF (600ºC) for as long as 15 minutes.[56] In fact, out of more than 170 areas examined on 16 recovered perimeter columns, only 3 reached temperatures in excess of 250ºC (450ºF) during the fires.[57] And why ? Well, perhaps, in part, because, as Shyam Sunder, the lead NIST investigator, admitted, “the jet fuel....burned out in less than ten minutes.”[58] Also, NIST scientists made another surprising discovery: The actual amount of combustibles on a typical floor of the WTC turned out to be less than expected: only about 4 lbs./sq. foot. Furthermore, “the fuel loading in the core areas....was negligible.”[59] The shocking fact is that the World Trade Center was fuel-poor, compared with most other buildings. The NIST estimated that a fire in a typical area of the building would have burned through the available combustibles at maximum temperatures (1,000ºC) in about 15-20 minutes.[60] Not nearly long enough even at that temperature to cause exposed steel to lose 80% of its strength.

Nor is this all. I searched the NIST report in vain for any acknowledgment that here, as in the case of the truss assembly test, the actual fire conditions on 9/11 were substantially different from the UL laboratory furnace. In fact, with respect to the columns the differences were at least as significant as with the truss assembly test, and call into sharp question the NIST’s conclusion that damaged insulation was the critical factor. Although the NIST took the position that “temperatures and stresses were high in the core area,”[61] as I’ve noted the investigation suffered from a persistent lack of information about real conditions at the core. The NIST had no hard evidence about the actual amount of protective insulation damaged/dislodged during the impacts. The NIST report acknowledges this,[62] then goes on to assume that all structural members in the debris path at the time of impact suffered 100% loss of insulation.[63] Surely, we are safe to conclude that the Boeing 767 impacts did cause damage to, or strip away, a substantial portion of the fireproofing material. Exactly how much is not knowable. But even if the NIST estimate of total loss of fireproofing is correct, there is virtually no chance that the fires on 9/11 weakened the WTC’s core piers within the allotted span of time: 56/103 minutes.

A Vast Heat Sink

The reason for this, nowhere acknowledged in the NIST report, ought to be obvious: The WTC’s support columns did not exist in isolation. This was no laboratory furnace. The columns in each tower were part of an interconnected steel framework that weighed at least 100,000 tons; and because steel is known to be an excellent conductor of heat this massive steel superstructure functioned on 9/11 as an enormous energy sink. The total volume of the steel framework was vast compared with the relatively small area of exposed steel, and would have wicked away much the fire-caused heat. Anyone who has repaired a copper water pipe with a propane torch is familiar with the principle. One must sit and wait patiently for the pipe temperature to rise to the point where the copper finally draws the solder into the fitting. While it is true that copper is more conductive than steel, the analogy holds, regardless. The fact that only three recovered steel samples showed exposure to temperatures above 250ºC indicates that the steel superstructure was indeed behaving as a heat sink. The fires on 9/11 would have taken many hours, in any event, much longer than the brief allotted span of 56/103 minutes respectively, to slowly raise the temperature of the steel framework as a whole to the point of weakening the exposed members.

And there are other problems. Since in a global collapse all of the columns by definition must fail at once, this implies a more or less constant blaze across a wide area. But this was not the case on 9/11. As already noted, the NIST’s lead investigator, Shyam Sunder, admitted that the jet fuel was consumed within minutes. Also, the NIST found that the unexpectedly light combustibles in any given area of the WTC were mostly consumed in about 15-20 minutes. At no point on 9/11 did the fires rage through a