9. Rapid Collapses and Conservation of Momentum and Energy

The NIST team fairly admits that their report,

“does not actually include the structural behavior of the tower after the conditions for collapse initiation were reached.”

(NIST, 2005, p. 80, fn. 12; emphasis added.)

Quite a confession, since much of the external evidence for explosive demolition typically comes after collapse initiation, as seen in cases of acknowledged controlled demolition. (Harris, 2000.) The NIST report could be called the official “pre-collapse theory.”

The rapid fall of the Towers and WTC7 has been analyzed by several engineers/scientists (Griffin, 2004, chapter 2). The roof of WTC 7 (students and I are observing the southwest corner as it commences its steady fall) falls to earth in (6.5 +- 0.2) seconds, while an object dropped from the roof (in a vacuum) would hit the ground in 6.0 seconds.


This follows from t = (2H/g)1/2. Likewise, the Towers fall very rapidly to the ground, with the upper part falling nearly as rapidly as ejected debris which provide free-fall references.


Where is the delay that must be expected due to conservation of momentum – one of the foundational Laws of Physics? That is, as upper-falling floors strike lower floors – and intact steel support columns – the fall must be significantly impeded by the impacted mass. If the central support columns remained standing, then the effective resistive mass would be less, but this is not the case – somehow the enormous support columns failed/disintegrated along with the falling floor pans. Peer-reviewed papers which further analyze the WTC skyscraper collapses, by Dr. Frank Legge, Professor Kenneth Kuttler, Gordon Ross and Kevin Ryan, are recommended and available here.

How do the upper floors fall so quickly, then, and still conserve momentum and energy in the collapsing buildings? The contradiction is ignored by FEMA, NIST and 9-11 Commission reports where conservation of energy and momentum and the fall-times were not analyzed. Gordon Ross argues that when conservation of energy and momentum are factored in, then a gravity-driven collapse will be arrested, so that only a partial collapse of the Tower would occur (see http://www.journalof911

studies.com/, Gordon Ross).


The paradox is easily resolved by the explosive demolition hypothesis, whereby explosives quickly remove lower-floor material including steel support columns and allow near free-fall-speed collapses (Harris, 2000).

And these explosives also readily account for the turning of the falling Towers to fine dust as the collapse ensues. Rather than a piling up with shattering of concrete as we might expect from non-explosive-caused progressive collapse (“official theory”), we find that most of the Towers material (concrete, carpet, etc.) is converted to flour-like powder WHILE the buildings are falling.


The Towers’ collapses are not typical random collapses, but quite possibly a series of “shock-and-awe” explosions coupled with the use of thermate-incendiaries – at least the evidence points strongly in this direction. The hypothesis ought to be explored further.

Those who wish to preserve fundamental physical laws as inviolate may wish to take a closer look. Consider the collapse of the South WTC Tower on 9-11:


click below image to watch video 

Top ~ 30 floors of South Tower topple over.
What happens to the block and its angular momentum?

We observe that approximately 30 upper floors begin to rotate as a block, to the south and east. They begin to topple over, not fall straight down. The torque due to gravity on this block is enormous, as is its angular momentum. But then – and this I’m still puzzling over – this block turned mostly to powder in mid-air! How can we understand this strange behavior, without explosives? Remarkable, amazing – and demanding scrutiny since the US government-funded reports failed to analyze this phenomenon. But, of course, the Final NIST 9-11 report,

“does not actually include the structural behavior of the tower after the conditions for collapse initiation were reached.”

(NIST, 2005, p. 80, fn. 12; emphasis added.)

Indeed, if we seek the truth of the matter, we must NOT ignore the data to be observed during the actual collapses of the towers, as the NIST team admits they did. But why did they follow such a non-scientific procedure as to ignore highly-relevant data? The business smacks of political constraints on what was supposed to be an “open and thorough” investigation. (See Mooney, 2005.)

So I with others call for an open and thorough investigation. I hope the international community will rise to the challenge. The field is wide open for considering the alternative hypothesis outlined here, due to its neglect in studies funded by the US government.

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10. Controlled Demolition “Implosions” Require Skill

The occurrence of nearly symmetrical, straight-down and complete collapses of the WTC 7 and the Towers is particularly upsetting to the “official” theory that random fires plus damage caused all these collapses. Even with high-level cutting charges, achieving such results requires a great deal of pre-planning and expertise.


As Tom Harris, an authority in this field, has explained:

The main challenge in bringing a building down is controlling which way it falls. Ideally, a blasting crew will be able to tumble the building over on one side, into a parking lot or other open area. This sort of blast is the easiest to execute. Tipping a building over is something like felling a tree. To topple the building to the north, the blasters detonate explosives on the north side of the building first…


Sometimes, though, a building is surrounded by structures that must be preserved. In this case, the blasters proceed with a true implosion, demolishing the building so that it collapses straight down into its own footprint (the total area at the base of the building). This feat requires such skill that only a handful of demolition companies in the world will attempt it.

Blasters approach each project a little differently... [A good] option is to detonate the columns at the center of the building before the other columns so that the building’s sides fall inward.... Generally speaking, blasters will explode the major support columns on the lower floors first and then a few upper stories… [nb: The upper floors then fall as a tamper, resulting in “progressive collapse”—this is common in controlled demolition.]

(Harris, 2000; emphasis added.)

Careful observation of the collapse of WTC 7 (video clips above) demonstrates a downward “kink” near the center of the building first, suggesting “pulling” of the support columns, then the building’s sides pull inward such that the building “collapses straight down into its own footprint” (Harris, 2000).


The plumes of debris observed on upper floors of WTC 7 as the collapse begins appear consistent with explosive cutting of supports for “a few upper stories” as outlined above.


FEMA admitted that WTC 7 collapsed onto a well-confined footprint:

The collapse of WTC 7 had a small debris field as the facade was pulled downward, suggesting an internal failure and implosion… The average debris field radius was approximately 70 feet.

(FEMA, 2002, chapter 5.)

Evidently we agree that this was a beautifully done implosion in the collapse of WTC 7, and yet:

This feat requires such skill that only a handful of demolition companies in the world will attempt it.

(Harris, 2000; emphasis added.)

Consider: Why would terrorists undertake straight-down collapses of WTC7 and the Towers, when “toppling-over” falls would require much less work and would do much more damage in downtown Manhattan? And where would they obtain the necessary skills and access to the buildings for a symmetrical implosion anyway? These questions suggest the need for further investigation.

One of the people a thorough investigation should question would be demolition expert Mark Loizeaux, president of Controlled Demolition, Inc. Speaking of the way the WTC buildings came down, he said in an interview:

“If I were to bring the towers down, I would put explosives in the basement to get the weight of the building to help collapse the structure.”

(Bollyn, 2002; emphasis added.)

Just right – “explosives in the basement” agrees with eyewitness reports of pre-collapse explosions down low in the buildings (point 7 above). Also, this would be the way to effectively sever the support columns, consistent with both the apparent initial drop of the communication tower (WTC Tower 1) and the “kink” in the middle of WTC 7 as its collapse began.


Yes, and as president of Controlled Demolition, Inc., Mr. Loizeaux would know the,

“handful of demolition companies in the world [that] will attempt” a symmetrical controlled demolition or “implosion”.

(Harris, 2000)

His company is certainly one of these and was hired to help in the rapid clean-up work following the building collapses.

In summary, we have discovered substantial evidence supporting the idea that thermites were used on the steel columns of the WTC Tower to weaken the huge steel supports, not long before explosives finished the demolition job. We can next estimate the amount of explosives needed by comparing with a known controlled demolition: the explosive demolition of the Landmark Tower.

“The explosive charges used to bring down the Landmark Tower [380 ft tall, 30 stories] weighed only 364 pounds [165 kilograms], consisting of 198 pounds of 60-percent nitroglycerine-based gel in 1-1/4 inch sticks, and 166 pounds of RDX (a C-4 derivative).”


Scaling to the 110-story WTC Towers, roughly 1300 pounds [590 kg] of explosives per Tower would suffice. Scaling to the size of WTC 7, 570 pounds [260 kg] would be indicated. The videos referenced above show WTC 7 falling top-down, in conventional controlled demolition fashion. On the other hand, the Towers were evidently demolished from the top downward, which although unusual is certainly possible using explosives. Indeed, for very tall towers such as these, top-down demolition seems be the best approach, to avoid toppling over of the tower onto surrounding buildings.

Explosives such as RDX, or HMX, or superthermites, when pre-positioned by a small team of operatives, would suffice to cut the supports at key points such that these tall buildings would completely collapse with little damage to surrounding buildings. Radio-initiated firing of the charges is implicated here, perhaps using superthermite matches. (See here)


Using computer-controlled radio signals, it would be an easy matter to begin the explosive demolition near the point of entry of the planes in the Towers (to make it appear that the planes somehow initiated the collapse.) In this scenario, linear cutter-charges would have been placed at numerous points in the building, mostly on the critical core columns, since one would not know beforehand exactly where the planes would enter.

Above: two men install a conventional cutter charge to steel column, preparing for a controlled demolition of the building. Notice the narrow width/size of the explosive cutter charge. From History Channel: “Wrecking ball – Modern marvels” and thanks to Robert Moore and http://piratenews.org/911con.html .

If you still haven’t looked at the rapid symmetrical collapse of WTC7 for yourself, why not do so now? Watch for the initial “kink” or drop in the middle, and for the “squibs” blowing in sequence up the side of the building, and notice the symmetrical, straight-down collapse. Furthermore, the collapse is rapid and complete, with the building falling quite neatly onto its own footprint. All of these features are common in controlled demolitions.


See for yourself at: http://911research.wtc7.net/talks/wtc/videos.html. A great deal of further information is presented from a serious scientific point-of-view at this site: http://wtc7.net/


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11. Steel Column Temperatures of 800°C Needed: A Problem in the Argument of Bazant and Zhou

A Mechanical Engineering professor suggested that I review a paper by Zedenek P. Bazant and Yong Zhou, which I did. Quoting:

The 110-story towers of the World Trade Center were designed to withstand as a whole the forces caused by a horizontal impact of a large commercial aircraft. So why did a total collapse occur?

(Bazant and Zhou, 2002, p. 2.)

Correct – the WTC Towers were designed to withstand forces caused by large commercial aircraft – we can agree on that. MIT’s Thomas Eagar also concurs,

“because the number of columns lost on the initial impact was not large and the loads were shifted to remaining columns in this highly redundant structure”

(Eagar and Musso, 2001).

We continue with Bazant & Zhou:

The conflagration, caused by the aircraft fuel spilled into the structure, causes the steel of the columns to be exposed to sustained temperatures apparently exceeding 800 oC… (Bazant and Zhou, 2002, p. 2.)

But here we note from the recent NIST report that:

“The initial jet fuel fires themselves lasted at most a few minutes” and office material fires would burn out within about 20 minutes in a given location.

(NIST, 2005; p. 179, emphasis added.)

Certainly jet fuel burning was not enough to raise steel to sustained temperatures above 800 oC. But we continue:

Once more than half of the columns in the critical floor.. suffer buckling (stage 3), the weight of the upper part of the structure above this floor can no longer be supported, and so the upper part starts falling down onto the lower part below…”

(Bazant and Zhou, 2002, p. 2.)

Bazant & Zhou do not explain how “more than half of the columns in the critical floor [can] suffer buckling” at the same time to precipitate the complete and nearly symmetrical collapse observed. There were 47 huge steel core columns in each Tower, and 24 such support columns in WTC 7 (NIST 2005; NISTb, 2005).

The WTC towers were solidly constructed with 47 steel core columns and 240 perimeter steel columns. 287 steel-columns total. Many doubt that random fires/damage could cause them to collapse straight down (official theory), and suspect explosives.

Steel-frame: Huge core (left) is an enormous heat sink. Notice workers standing on floor pan which is firmly attached to the interconnected core columns.

They do NOT explain how steel-column temperatures above 800 oC were achieved near-simultaneously due to burning office materials. NIST notes that office materials in an area burn for about 15-20 minutes, then are consumed away (NIST, 2005, pp. 117, 179). This is evidently not long enough to raise steel column temperatures above 800 oC as required in the Bazant & Zhou model, given the enormous heat sinks of the structures. And to have three buildings completely collapse due to this unlikely mechanism on the same day strains credulity.

Moreover, the Final NIST report on the Towers admits:

Of the more than 170 areas examined on 16 perimeter column panels, only three columns had evidence that the steel reached temperatures above 250 ºC… Only two core column specimens had sufficient paint remaining to make such an analysis, and their temperatures did not reach 250 ºC. ... Using metallographic analysis, NIST determined that there was no evidence that any of the samples had reached temperatures above 600 ºC.

(NIST, 2005, pp. 176-177; emphasis added.)

Relevant to this point, Eagar noted that,

“Factors such as flame volume and quantity of soot decrease the radiative heat loss in the fire, moving the temperature closer to the maximum of 1,000 ºC.”

(Eagar and Musso, 2001)

While this is the maximum air temperature possible in the WTC fires, this does not mean that the structural steel reached this temperature in the time the fires acted.


Indeed, NIST emphasizes that there was no evidence that “any of the samples had reached temperatures above 600 ºC.” This statement is consistent with their data plots of “predicted column temperatures”, which “shows maximum temperature reached by each column” in that no temperature above 600 ºC is given for any of the steel columns. (NIST, 2005.)

As for WTC 7, Bazant & Zhou say little but mention in a separate “addendum” that burning natural gas might have been a source of the needed heat (Bazant and Zhou, March 2002, p. 370).


The FEMA report (FEMA, 2002) addresses this issue:

Early news reports had indicated that a high pressure, 24-inch gas main was located in the vicinity of the building [WTC 7]; however, this proved not to be true.”

(FEMA, 2002, chapter 5; emphasis added.)

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12. Problems in the NIST Report: Inadequate Steel Temperatures and Tweaked Models

I have read through the hundreds of pages of the Final NIST report on the collapses of the WTC Towers. (NIST, 2005) It is interesting to note that NIST “decoupled” and delayed their final report on WTC 7, which is overdue as of this writing (NIST, 2005; NISTb, 2005). I agree with some of the NIST report; for example:

Both WTC 1 and WTC 2 were stable after the aircraft impact, standing for 102 min and 56 min, respectively. The global analyses with structural impact damage showed that both towers had considerable reserve capacity. This was confirmed by analysis of the post-impact vibration of WTC 2… where the damaged tower oscillated at a period nearly equal to the first mode period calculated for the undamaged structure.

(NIST, 2005, p. 144; emphasis added.)


At any given location, the duration of [air, not steel] temperatures near 1,000 oC was about 15 min to 20 min. The rest of the time, the calculated temperatures were near 500 oC or below.”

(NIST, 2005, p. 127, emphasis added.)


NIST contracted with Underwriters Laboratories, Inc. to conduct tests to obtain information on the fire endurance of trusses like those in the WTC towers… All four test specimens sustained the maximum design load for approximately 2 hours without collapsing.”

(NIST, 2005, p. 140, emphasis added.)

However, I along with others challenge NIST’s collapse theory. NIST maintains that all three building collapses were fire-initiated despite the observations above, particularly the fact that fire endurance tests with actual models did not result in collapse. In a paper by fire-engineering experts in the UK, we find:

The basis of NIST’s collapse theory is… column behaviour in fire... However, we believe that a considerable difference in downward displace between the [47] core and [240] perimeter columns, much greater than the 300 mm proposed, is required for the collapse theory to hold true… [Our] lower reliance on passive fire protection is in contrast to the NIST work where the amount of fire protection on the truss elements is believed to be a significant factor in defining the time to collapse… The [proposed effect] is swamped by thermal expansion … Thermal expansion and the response of the whole frame to this effect has NOT been described as yet [by NIST].

(Lane and Lamont, 2005.)


I agree with these pointed objections, particularly that the “response of the whole frame” of each building should be considered, especially heat transport to the whole frame from localized fires, and that the “core columns cannot pull the exterior columns in via the floor.”

(Lane and Lamont, 2005)

The computerized models of the Towers in the NIST study, which incorporate many features of the buildings and the fires on 9-11-01, are less than convincing. The Final report states:

The Investigation Team then defined three cases for each building by combining the middle, less severe, and more severe values of the influential variables. Upon a preliminary examination of the middle cases, it became clear that the towers would likely remain standing. The less severe cases were discarded after the aircraft impact results were compared to observed events. The middle cases (which became Case A for WTC 1 and Case C for WTC 2) were discarded after the structural response analysis of major subsystems were compared to observed events.

(NIST, 2005, p. 142; emphasis added.)

The NIST report makes for interesting reading. The less severe cases based on empirical data were discarded because they did not result in building collapse. But ‘one must save the hypothesis,’ so more severe cases were tried and the simulations tweaked, as we read in the NIST report:

The more severe case (which became Case B for WTC 1 and Case D for WTC 2) was used for the global analysis of each tower. Complete sets of simulations were then performed for Cases B and D. To the extent that the simulations deviated from the photographic evidence or eyewitness reports [e.g., complete collapse occurred], the investigators adjusted the input, but only within the range of physical reality. Thus, for instance,…the pulling forces on the perimeter columns by the sagging floors were adjusted...

(NIST, 2005, p. 142; emphasis added.)

The primary role of the floors in the collapse of the towers was to provide inward pull forces that induced inward bowing of perimeter columns.

(NIST, 2005, p. 180; emphasis added.)

How fun (perhaps) to tweak the model like that, until the building collapses—until one gets the desired result. But the end result of such tweaked computer hypotheticals is not compelling. Notice that the “the pulling forces on the perimeter columns by the sagging floors were adjusted”
(NIST, 2005, p. 142; emphasis added) to get the perimeter columns to yield sufficiently – one suspects these were “adjusted” by hand quite a bit—even though the UK experts complained that “the core columns cannot pull the exterior [i.e., perimeter] columns in via the floor.”

(Lane and Lamont, 2005; emphasis added.)

I also agree with Kevin Ryan’s objections regarding the NIST study. Kevin Ryan, at the time a manager at Underwriters Laboratories (UL), makes a point of the non-collapse of actual WTC-based models in his letter to Frank Gayle of NIST:

As I’m sure you know, the company I work for certified the steel components used in the construction of the WTC buildings. In requesting information from both our CEO and Fire Protection business manager last year… they suggested we all be patient and understand that UL was working with your team… I’m aware of UL’s attempts to help, including performing tests on models of the floor assemblies. But the results of these tests… indicate that the buildings should have easily withstood the thermal stress caused by… burning [jet fuel, paper, etc.].

(Ryan, 2004)

That models of WTC trusses at Underwriter Laboratories (UL) subjected to fires did NOT fail is also admitted in the final NIST report:

NIST contracted with Underwriters Laboratories, Inc. to conduct tests to obtain information on the fire endurance of trusses like those in the WTC towers…. All four test specimens sustained the maximum design load for approximately 2 hours without collapsing… The Investigation Team was cautious about using these results directly in the formulation of collapse hypotheses. In addition to the scaling issues raised by the test results, the fires in the towers on September 11, and the resulting exposure of the floor systems, were substantially different from the conditions in the test furnaces. Nonetheless, the [empirical test] results established 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.

(NIST, 2005, p. 141; emphasis added.)

So how does the NIST team justify the WTC collapses, when actual models fail to collapse and there are zero examples of fire-caused high-rise collapses? Easy, NIST concocted computer-generated hypotheticals for very “severe” cases, called cases B and D (NIST, 2005, pp. 124138). Of course, the details are rather hidden to us. And they omit consideration of the complete, rapid and symmetrical nature of the collapses.

Indeed, NIST makes the startling admission in a footnote on page 80 of their Final Report:

The focus of the Investigation was on the sequence of events from the instant of aircraft impact to the initiation of collapse for each tower. For brevity in this report, this sequence is referred to as the “probable collapse sequence,” although it does not actually include the structural behavior of the tower after the conditions for collapse initiation were reached...

(NIST, 2005, p. 80, fn. 12; emphasis added.)

Again, on page 142, NIST admits that their computer simulation only proceeds until the building is “poised for collapse”, thus ignoring any data from that time on. The results were a simulation of the structural deterioration of each tower from the time of aircraft impact to the time at which the building became unstable, i.e., was poised for collapse. ...

(NIST, 2005, p. 142; emphasis added.)

  • What about the subsequent complete, rapid and symmetrical collapse of the buildings?

  • What about the observed squibs?

  • What about the antenna dropping first in the North Tower?

  • What about the molten metal observed in the basement areas in large pools in both Towers and WTC 7 as well?

Never mind all that: NIST did not discuss at all any data after the buildings were “poised for collapse.”


Well, some of us want to look at ALL the data, without “black-box” computer simulations that are “adjusted,” perhaps to make them fit the desired outcome. An hypothesis which is non-refutable is non-scientific. On the other hand, Occam’s razor suggests that the simplest explanation which addresses and satisfies ALL the evidence is most probably correct.


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