The Pacifica Radio ''Twin Towers Debate'' on 9/11/2011

by Ron Brookman, S.E.

Thank you to Mickey Huff and KPFA radio for hosting the Twin Towers debate on the tenth anniversary of September 11. Richard Gage and Niels Harrit described hard evidence for the controlled-demolition hypothesis; Dave Thomas and Richard Muller promoted the fire-induced collapse hypothesis. Listen to the entire debate at http://www.kpfa.org/archive/id/73245.

Richard Gage, AIA is a San Francisco Bay Area architect and founder of AE911Truth—a nonprofit organization with over 1,600 professional architects and engineers plus over 13,000 others who are calling for a science-based investigation of the destruction of the three high-rise buildings.1

Dr. Niels Harrit, associate professor emeritus of chemistry from the University of Copenhagen, has published over 60 peer-reviewed papers in scientific journals including ''Active Thermitic Material Discovered in Dust from the 9/11 World Trade Center Catastrophe."2

Dave Thomas, physicist and mathematician, has been researching 9/11 conspiracy theories since 2009. He is president of New Mexicans for Science and Reason and a fellow of the Committee for Skeptical Inquiry.3

Dr. Richard Muller, professor of physics, has a long resume of research and academic appointments at UC Berkeley, the Lawrence Berkeley Laboratory and the Space Sciences Laboratory. Dr. Muller is well known for his book Physics for Future Presidents—the Science Behind the Headlines (2008).4

Dave Thomas started by framing the debate in a political context with a statement supporting an investigation—into the rationale for the Iraq War. He categorically denied empirical evidence of explosions stating ''…there was no boom, boom, boom that you always hear…'' Apparently Thomas has never read eyewitness accounts of first responders in the FDNY Oral Histories5; he has never heard exhausted and bleeding firefighters describing explosions on video released by the National Institute of Standards and Technology (NIST) to the International Center for 9/11 Studies6. Thomas's opinion—that the Towers' unique design was vulnerable to catastrophic collapse following aircraft impact and fire—was not supported by science. The Structural Engineer of Record, John Skilling, understood the design and construction of the towers when he stated (after the first demolition attempt in 1993) that the ''building structure would still be there." Skilling knew the Towers were designed to withstand the impact of a Boeing 707 without a catastrophic failure.7

Gage's introductory statement emphasized that the official account is a grand conspiracy theory for which there is little evidence. Key points made by Gage include: NIST has repeatedly denied the existence of relevant evidence in its seven-year study; NIST concluded the collapses were due to impact and fire damage, and no explosives were present; NIST, however, never tested for explosives residues. Esteemed scientist Dr. Lynn Margulis, recipient of the President's Medal of Science and the Da Vinci Award, agrees:

 

So this is what NIST has done, denied and ignored crucial evidence. It doesn't fit their preconceived notions.8

Dr. Muller's introductory statement was intended to stick to the physics, and his reaction to seeing the Towers collapse was ''Oh—of course." He may be the first person on record who was not surprised upon seeing two massive 110-story office towers each dissolve into an avalanche of debris. Muller proceeded to explain why he expected the Twin Towers to collapse:

Gasoline, the reason we use it, the reason we love it is because it has so much energy.

I see nothing to love about the destructive energy displayed on 9/11. Muller continued with a brief introduction to engineering mechanics as it applies to high-rise building destruction by fire:

These columns are designed to hold up twice as much weight as they actually hold, but once they lose half of their strength they are bound to buckle…Once a column buckles—take a soda straw and squeeze it between your hands...

Did it ever occur to Dr. Muller that there may be structural engineers listening who know the difference between buckling of steel columns and buckling of plastic drinking straws, and some listeners may find this analogy offensive? The modulus of elasticity of steel is roughly 100 times that of plastics used for drinking straws, and the slenderness ratio of a drinking straw is roughly three times the slenderness ratio of a perimeter column in the upper stories of the WTC. You could not buckle the same straw by hand if it was made of steel.

Typical columns may be designed with a safety factor of approximately two. The columns of the Twin Towers, however, were not typical columns. They were designed to equalize axial stresses and column shortening during construction due to their extreme height. This enabled the high-strength steel perimeter columns to have much greater reserve capacity than ''typical'' columns. An Engineering News Record article from July 8, 1965 stated:

A design procedure that will be used for structural framing of the 1,350-ft high twin towers of the World Trade Center in New York City gives the exterior columns tremendous reserve strength. Live loads on these columns can be increased more than 2,000% before failure occurs…Exterior columns will be spaced 39 inches c-c. Made of various high-strength steels, they will be 14-inch square hollow-box sections, for high torsional and bending resistance, and windows will be set between them. Spandrels welded to the columns at each floor will convert the exterior walls into giant Vierendeel trusses…Thus, the World Trade Center towers will have an inherent capacity to resist unforeseen calamities. This capacity stems from its Vierendeel wall system and is enhanced through the use of high-strength steels.9

For some reason Dr. Harrit was not given a three-minute statement of introduction. His one-minute rebuttal emphasized the importance of historical precedent and observation in science. Fire has never caused a steel-frame high-rise building to collapse prior to 9/11, and the energetic jet fuel was quickly consumed in the initial fireball and the first few minutes of fire. Fuel was primarily office furnishings. So how do burning desks and papers create molten-iron residues discovered in abundance in the debris?10

Gage's second statement explored the collapse of WTC7 and David Chandler's measurements of free-fall acceleration. NIST has admitted free fall, but has yet to provide any rational explanation for this.11 An important question was raised: What happened to the column resistance to allow free-fall motion to occur?

Column buckling requires energy, and deforming steel beyond the elastic range dissipates energy. But free fall—or gravitational acceleration—converts gravitational potential energy to kinetic energy with nothing left to perform the mechanical work required to squash a structural steel frame supporting 40 stories. Additional energy was required to overcome the resistance of structural elements. Dr. Sunder of NIST acknowledged this during the technical briefing held on August 26, 2008 as he attempted to answer Chandler's question: ''How can such a publicly visible, easily measurable quantity be set aside?"12

Dr. Sunder's response included:

…a free-fall time would be an object that has no structural components below it…

…you had a sequence of structural failures that had to take place, and everything was not instantaneous.

Unfortunately none of these comments were acknowledged in the final NCSTAR reports issued in November 2008. There was clearly no rational explanation in the final reports for the observed free-fall motion.

Thomas's rebuttal addressed the question of free fall by invoking the NIST report's three-stage collapse.13 Anyone can see that the global-collapse simulation of WTC 7 does not correlate to the video documentation. There is no video or photographic evidence showing stage one—allegedly a buckling failure of 58 perimeter columns within two seconds.

Dr. Harrit emphasized the inadequacy of the NIST three-stage collapse progression. The global-collapse simulation of WTC 7 does not demonstrate the observed motion, so there's no compelling reason to accept the NIST conclusions.

Dr. Muller's rebuttal consisted of more mechanics of buckling.

I really recommend members of the audience take a sheet of paper, 8x10, roll it into a cylinder, put a little scotch tape on it and then put it on its end and put a book on top. It's amazing that paper can hold up a book. Then put a second book on top, then a third and add them up until the thing collapses. You'll find that when it collapses, it doesn't take energy, it doesn't take time. The whole thing collapses very suddenly. This is the nature of buckling. It doesn't take very much energy, and it is very fast.

I tried Dr. Muller's experiment with a sheet of paper rolled into a cylinder 8.5 inches long and about 3.5 inches in diameter. The third book crumpled the cylinder and flattened it in a blink. A second experiment with the paper rolled to about two-inch diameter required four books to crumple one end, and the cylinder collapsed to one side. Both experiments can be described as local-buckling failures of thin-walled cylinders.

What does this say about structural steel columns in the lower stories of a 47-story building? Nothing, other than buckling is a real failure mode that must be considered in the design of columns, and don't try supporting buildings of any size on paper cylinders. To imply buckling of steel columns takes little energy is nonsense. Columns require excessive strain energy due to applied axial load before they can reach their critical buckling strength. There was no excess weight straining the columns of WTC 7 on the afternoon of 9/11, so why should 58 perimeter columns and 24 interior columns all buckle roughly simultaneously?

Thomas claimed that WTC7 had ''huge fires that raged for seven hours" referring to the period between 10:30 a.m. when the North Tower collapsed and 5:20 p.m. when WTC 7 collapsed. Gage stated correctly that this claim is grossly exaggerated as the photographic record proves. The earliest visual evidence showing flames in WTC 7 is a video clip of the southwest corner recorded after 12:00 p.m.14 The northeast corner of WTC 7 was photographed at around 4:00 p.m. NIST says ''…there is no indication of fires burning on the east side of the 12th floor at this time."15 The north face at floors 10 through 14 was also photographed at around 4:38 p.m. In NIST's words ''All of the visible windows on the 12th and 13th floors are open in Figure 5-149. There is no indication of fire at these locations on either floor."16 Indeed, all the windows appear dark where the NIST fire simulation indicated raging fires. Thomas's claim is easily disproven by reading NCSTAR 1-9 Chapter 5.

On one hand Thomas favors the NIST report, and on the other hand he indicated that some building professionals have disagreed with the NIST draft report. What Thomas did not say was that most of the public comments submitted to NIST were ignored.17 Free fall, however, was not ignored for good reasons stated previously. How many building professionals have embraced NIST's final reports?

Dr. Muller continued with the structural engineering lessons:

…buildings are like houses of cards…They are made lightweight on purpose so that you don’t have to have a huge structure at the bottom to hold it up…

What? Buildings are like houses of cards? This is not what I recall learning in the College of Engineering at UC Davis or in 25 years practicing structural engineering. What would the UC Structural Engineering professors say about Muller's characterization of structural design principles? Fortunately he added:

…these things [the Twin Towers] are really solid at the bottom too.

Observing scientific principles, Dr. Harrit stated facts regarding the Cardington fire tests performed in the UK where unprotected steel beams achieved temperatures of up to 1,150° Centigrade without failure.18 Steel samples from the fire-affected floors of the Twin Towers were tested by NIST but reached only 250 degrees Centigrade.19 The highest column temperatures in WTC 7 were estimated at 300 degrees Centigrade20 —not hot enough to weaken steel.

Gage's statement regarding molten steel, iron microspheres and extreme temperatures21 was clear and concise. Anyone listening who was not already familiar with this evidence would be alarmed. Thomas, far from being alarmed, simply dismissed the molten steel as molten aluminum from the aircraft or building exterior cladding.

Thomas claimed the chemical signature of thermite (a mixture of iron oxide and aluminum) was not found in the WTC dust. His ''explanation'' for the energetic red-gray chips found by Dr. Steven Jones was that they were primer paint from open-web steel trusses used in the original construction of the towers. The research done by Harrit and others tested this possibility, and the chips were not red-oxide primer paint.22

Readers who have come this far should now have a sense of the nature of this debate. The conclusion will be left for listeners to discover at http://www.kpfa.org/archive/id/73245, and I will close this discussion with a few words about Dr. Muller's book mentioned previously.

Physics for Future Presidents—the Science Behind the Headlines, Chapter One, briefly discusses aircraft impact, energy contained in the jet fuel, and the ''sledgehammer'' effect crushing the intact structure floor by floor. His hammer-and-nail analogy, however, does not explain the lack of deceleration at the moment of floor impact—otherwise known as the missing jolt.23 A brief and tenuous theory for the collapse of WTC 7 concludes Chapter One, and it does not even mention free fall.

When the building [WTC 1] collapsed, it brought down with it whatever jet fuel had not yet been consumed. The continued burning of this fuel caused the collapse (again, because of weakening of columns) of the nearby Building 7.

The FEMA 403 report, however, states:

...it is believed that almost all of the jet fuel that remained [following the initial fireball] on the impact floors was consumed in the first few minutes of the fire.24

This makes sense. And NIST NCSTAR 1-9 states:

…exterior columns and core columns [of WTC 7] also did not heat significantly on the fire floors.25

How—after 103 minutes of fire in WTC 1—was there enough jet fuel remaining to bring down WTC 7? And how could scattered fires on several floors cause a complete collapse at free-fall acceleration? This defies common sense. Future presidents and alert citizens deserve an honest explanation that meets strict standards for scientific integrity.

Thank you to all participants in the Twin Towers debate for an enlightening hour. With all due respect for their accomplishments, if Dave Thomas and Richard Muller are the most qualified proponents for the fire-induced collapse hypothesis put forth in the NIST reports, then I'll continue studying the science and standing with Richard Gage and Niels Harrit.

Ronald H. Brookman, SE

 


[1] See http://www.ae911truth.org.
[2] See http://nielsharrit.org.
[3] See http://www.nmsr.org.
[4] See http://muller.lbl.gov.
[5] See http://graphics8.nytimes.com/packages/html/nyregion/20050812_WTC_GRAPHIC/met_WTC_histories_full_01.html.
[6] See http://www.youtube.com/user/IC911STUDIES#p/u/5/IO1ps1mzU8o.
[7] See http://community.seattletimes.nwsource.com/archive/?date=19930227&slug=1687698.
[8] See http://www.youtube.com/watch?v=g-GFBEX5bjY.
[9] See http://911research.wtc7.net/mirrors/guardian2/wtc/eng-news-record.htm.
[10] Steven E. Jones et al., ''Extremely High Temperatures during the World Trade Center Destruction", Journal of 9/11 Studies, Volume 19, January 2008. See http://journalof911studies.com/articles/WTCHighTemp.pdf.
[11] S. Shyam Sunder et al., NIST NCSTAR 1A, Final Report on the Collapse of World Trade Center Building 7, Washington: U.S. Government Printing Office, November 2008, p. 45.
[12] See http://www.youtube.com/watch?v=eDvNS9iMjzA&list=PL206C1F5EDFC83824&index=1.
[13] Sunder et al.
[14] Therese P. McAllister et al., NIST NCSTAR 1-9, Structural Fire Response and Probable Collapse Sequence of World Trade Center Building 7, Washington: U.S. Government Printing Office, November 2008, p. 194.
[15] NCSTAR 1-9, Fig. 5-141, p. 227.
[16] NCSTAR 1-9, p. 235.
[17] See http://www.nist.gov/el/disasterstudies/wtc/upload/combined2008publicComments-2.pdf.
[18] See http://911research.wtc7.net/mirrors/guardian2/fire/cardington.htm.
[19] Frank W. Gayle et al., NIST NCSTAR 1-3, Mechanical and Metallurgical Analysis of Structural Steel, Washington: U.S. Government Printing Office, September 2005, p. xli.
[20] Sunder et al., p. 21.
[21] Jones et al.
[22] Harrit et al.
[23] Graeme MacQueen and Tony Szamboti, ''The Missing Jolt: A Simple Refutation of the NIST-Bazant Collapse Hypothesis'', Journal of 9/11 Studies, Volume 19, January 2008. http://journalof911studies.com/volume/2008/TheMissingJolt7.pdf.
[24] Ronald Hamburger et al., FEMA 403, Ch.2, ''WTC 1 and WTC 2'', p. 2-22.
[25] NCSTAR 1-9, p. 394.

Muller a Sad Case

Richard Muller is a hugely popular physics teacher - now on the web world-wide. Unfortunately, he was on the list for having attended Bohemian Grove, so anything he says about government sponsored physics theories and its misinformation is highly suspect.

After meeting the head of UCB engineering (no longer at the school) before Obama was even nominated, and telling him about Muller's crackpot theory of collapse on 9/11 in his webcast from UCB, he was upset. He told me, "I'm going into Muller's office as soon I get back and tell him off. It was definitely explosives...." Too bad this head of department couldn't state his own beliefs publicly - we'd be much further along if he had.

Ronald Brookman, SE

...did an excellent job of critiquing the debate. Well done and thanks.

Well done indeed

Great essay Mr Brookman, thank you for speaking out.

Curious, were original blueprints for any of the WTC buildings ever released? I would like to see a real 3D computer model done that account for free fall and the uniform acceleration of the north tower. And of course, the tilt of the south tower too. I'd give money to support that project for sure.

Thanks again Mr. Brookman

peace all

dtg

Is there such a thing as a "good" 9/11 debate?

I don't know if these debates really serve the ultimate goal of informing the public and reinforcing the impetus toward a new investigation.

First, debates limit discourse, therefore it becomes about making a single point at at time, quickly, and not always successfully.

Second, these debates give credibility to deniers. Doesn't matter WHAT they say, if they say it with great authority and with the credentials to back them up, then the uniformed listener who is leaning toward denial will suck that up like manna in the desert. I hear this every time there is a debate. Generalizations, half-truths, lies, misrepresentations, presented with authority. That's all it takes and that all the denier wants.

Obviously the truth is irrelevant to the denier who engages in debate.

I hope we will see fewer and fewer of them in the future.

My two cents.

The initial reasons for debates on the 911 issue were to

show that there were mature credible people asking serious questions about the explanations we have thus far been given concerning the events which transpired on Sept. 11, 2001. That phase can probably be considered complete.

I would agree that it is appropriate to question just what can be gained by engaging with someone willing to lie in a situation where it is difficult to pin them down due to the fast pace of the format.

However, this particular debate did give rise to a series of continued confrontations of Richard Muller and Dave Thomas showing their claims to be in error. This synopsis by Ron Brookman is a good example.

For better or worse, people

For better or worse, people did hear the interview on the radio and I do keep hearing people mention it to me in my area.

At least it keeps the conversation alive.. Debating is a technique and skill on its own too, many people who are researched on 9/11 are not good debaters.

I think you and Bob on Geraldo did very good. No debate needed.

Here is what I wrote to Richard Muller

while copying Dave Thomas, Niels Harrit, and Richard Gage, shortly after the debate.

Richard,

It is a shame that during the KPFA debate tonight you didn't provide the numbers on and explain that there is a minimum resistance in a buckling steel column. Comparing them to a rolled paper column is not an accurate analogy. Maybe you believe what you are saying and don't know any better, but it is not accurate. See the attached slide, which can also be found in figure 5d of the attached Zdenek Bazant 2002 paper.

The minimum resistance during buckling is a function of the plastic moment and the unsupported length of the column. In a one story unsupported length of the Twin Tower box columns it was approximately 25% of the yield strength of the column. For the wide flange columns in the core it was lower at about 14% of yield.

The wide flange core columns at the 98th floor of the North Tower had a minimum factor of safety against gravity of 3 and the perimeter box columns a minimum factor of safety against gravity of 5. The core columns would have to buckle over one story with their moment connected beams at each floor, so they would provide a minimum resistance during buckling of about 42% of their load. A case could be made that the perimeter columns initially buckled over two stories and thus their resistance would be 12.5% of yield, so they would have still provided a resistance of 65% of their load. The load split between the core and perimeter was 42% core and 58% perimeter. The resistance during buckling would thus be (0.42)(0.42) + (0.58)(0.65) = 0.55. So the resistance to the actual load during buckling would have been a minimum of about 0.55g.

Given the above reality, it is incredible that Dave actually tries to claim freefall was occurring in the towers between impacts punctuated by 31 G decelerations of 2 millisecond duration. What is also incredible about Dave's figures is that he claims a 31 G deceleration with a 2 millisecond duration would provide enough energy to crush/collapse the next floor down. If the building at initiation went into freefall for 0.88 seconds, the way Dave suggests, it would have been moving at a velocity of 28.3 ft/s or 19 mph at impact. A 31 G deceleration is -997 ft/s/s and with a 2 millisecond duration this deceleration would cause a 2 ft/s velocity loss. Since kinetic energy is a function of velocity squared, the energy loss as a percentage of original is (2 x 2)/(28.3 x 28.3) = 4/800.89 or just 0.5%. So Dave is essentially saying that just 0.5% of the kinetic energy would be needed. This is incredible and I seriously doubt that he has calculations to back up what he says here. Even Zdenek Bazant, who with his use of nearly double the actual mass and freefall, generating about 7 times more kinetic energy than what there actually was, comes up with a number of 12%. I have been involved in the calculation of the column energy dissipation and have written a paper with other academics, where we conservatively determined it would have been about 76% of the kinetic energy, using the real mass of the upper section of WTC 1 of 33 million Kg, the real column cross sections, an acceleration of 0.70 g and velocity at impact of 22.8 ft/s, and also involved the energy dissipation by the upper section columns, which Bazant didn't. This large kinetic energy drain shows the constant acceleration of the tower to be a serious problem for the present official story.

In reading Dave's article in the Skeptical Inquirer I had to wonder why his figure on the third page of the article showed the towers with a central core which was at least 3 to 4 times smaller in scale, length and width wise, than it was in reality. I also had to wonder where he got a 58 million Kg mass for the 12 story upper section of the North Tower. It was 33 million Kg. Zdenek Bazant makes a similar error in his January 2011 paper, forgetting that he did an accurate mass analysis using vibrational frequency showing that 44% of the mass of the tower was 141 x 10e6 Kg. Using this value, and extrapolating over 117 stories, each story has a mass of approximately 2.74 x 10e6 Kg, and 12 stories would be 32.88 x 10e6 Kg or approximately 33 million Kg. Bazant's correct analysis can be found on page 7 of his 2002 paper in the addendum. I am not sure where the 58 million Kg came from, but I think it might be related to the 54.8 million Kg mass Bazant was using for 20 stories, where he seems to have been averaging between the 12 story upper section of the North Tower and the 28 story upper section of the South Tower. Dave would also be wrong about thermite never having been used for demolition. Interestingly, a Popular Mechanics issue from 1933 shows it was used to fell one of the 628 foot tall towers from the Century of Progress World's Fair in Chicago, see the Wikipedia article on it here http://en.wikipedia.org/wiki/Sky_Ride. Additionally, WTC 7 could not come down in freefall while its columns were buckling for the reasons I showed above, and it didn't start to tilt over until it was about 60% of the way down and well beyond that initial 8 story (100 foot) freefall. There were more problems with the Skeptical Inquirer article by Dave Thomas but I have listed the most serious here.

Since Dave depends so much on Zdenek Bazant's work, I feel it only fair to tell you and him that his latest paper on the WTC collapses has serious fatal flaws in it, and that this has been reported to the Journal of Engineering Mechanics. I am attaching a reply by Richard Johns and myself here (which should be published some time in the near future) along with Bazant's January 2011 paper and a third pdf showing what the deceleration should have been at first impact, if the actual acceleration through the 1st story was used. We still allowed Bazant's freefall through the 1st story in our reply, as it wasn't necessary to refute him there and we were limited to 2,000 words, which included figures pro-rated at 1,260 words per page.

I also want to mention the failure to explain in detail that while the energy density of jet fuel and gasoline is about 15 times greater than that of TNT, that it does not release its energy nearly as fast and as such is not nearly as powerful. Remember, power is energy or work per unit time. I think you may have said it was 40 times greater, which is not true but I understand where you were coming from. I have to say that if I were in a debate where the energy density of gasoline and jet fuel were being used, without explaining all of the details, I would bring up the fact that chocolate chip cookies have 8 times the energy density of TNT. See http://geophysics.nmsu.edu/chapter01.html. Thermite, and nano-thermite even more so due to it's higher reaction rate, releases it's energy much faster than gasoline or jet fuel and is significantly more powerful than gasoline or jet fuel. By the way, we can also compare the potential energy of the towers to chocolate chip cookies, as you guys do to TNT (where you say it was equal to 100 tons of TNT). Like your analogy, this really has nothing to do with the argument, but in a debate I would counter by saying it was also equal to 12.5 tons of chocolate chip cookies. I am sure you'll understand what I mean here if I say the saying "if you can't dazzle them with brilliance, baffle them with bullshit" would apply in all cases of the use of these analogies without further clarification.

Additionally, I must say I have to wonder why you are content to simply assume high steel temperatures caused the collapses when NIST did not find evidence for that. A point that Niels did bring up. Any mature person should also be wondering why none of the steel from WTC 7 and less than 0.5% of it from the twin towers was saved for NIST to use in their investigation. One can't say an analysis was done before NIST got involved a year later, as there was no actual analysis done other than that on the few small pieces in the FEMA Appendix C report. Thankfully, Dr. Jonathan Barnett did tell us that experts like him were prevented from examining and analyzing the vast majority of the steel.

Regards,

Tony Szamboti
Mechanical Engineer
Blackwood, NJ

Note: I can't attach the referenced papers here but if you e-mail me I can send them to you or anyone else who wants to see the proof of the complete incorrectness of Zdenek Bazant's latest work and the inferences showing that is true of everything he has done on the WTC disasters.

Well crafted reply

I'm glad that you also noted the following, as it often gets overlooked in 9/11 debates:

"Any mature person should also be wondering why none of the steel from WTC 7 and less than 0.5% of it from the twin towers was saved for NIST to use in their investigation. One can't say an analysis was done before NIST got involved a year later, as there was no actual analysis done other than that on the few small pieces in the FEMA Appendix C report. "

Destroying the research material without investigation - especially clear in the case of WTC 7 - should IMHO be emphasized. It is easy to show that the investigation was not legitimate.

One really shouldn't even need to go into details. For WTC 7, these points should suffice, with emphasis on the first two:

1) It was destroyed in a way that matches a skilled controlled demolition.

2) The research material was destroyed before NIST started its investigation, followed by years of official hypotheses.

3) The building fell at free-fall acceleration across eight stories, which NIST finally admitted but did not explain.

Correction to Dave Thomas' kinetic energy

In Dave Thomas' made up scenario of an unobservable 31g impulse with a 2 millisecond duration I stated correctly that there the velocity loss would have been about 2 ft./s, but percentage of the kinetic energy lost needs to be calculated by subtracting the square of what is left from the square of the original and dividing by the square of the original, due to it being non-linear. Going from the Dave Thomas' original of 28.3 ft./s to 26.3 ft./s would be 28.3 squared - 26.3 squared over 28.3 squared and is (800.89 - 691.69)/800.89 = 13.6%.

13.6% of the kinetic energy after a one-story fall is still ridiculously below what would have been needed to continue a collapse and Dave did not do any column resistance calculations to see what was needed. By his own admission he uses freefall through the stories, even though it is impossible naturally. It is clear that he simply worked backwards from the acceleration measured by David Chandler and just plugged in made up g-level values for the impacts with freefall through stories to gain an average to match what David Chandler measured.

Zdenek Bazant's 12% kinetic energy loss was also for 2 stories, so even he claims a 24% loss after a fall of one-story and he exaggerates the kinetic energy by several times what it actually was, by nearly doubling the mass, and erroneously using freefall acceleration through the initial fall which gives a velocity about 1.5 times what it actually was, which when squared gives 2.25 times more energy by itself. Bazant does look at the columns but he only accounts for about half of the actual resistance.

Both of these guys are ridiculously erroneous at best.

Simple Math For The Rest of Us

Dr. Muller's Quote:

"These columns are designed to hold up twice as much weight as they actually hold, but once they lose half of their strength they are bound to buckle"

If they are designed to hold two times (2X) the weight they actually are holding, then if they lose half their strength (1X), they are still capable of supporting the load (1X).

2X - 1X = 1X

It sounds like Dr. Muller is using this formula:

2X - 1X = 0

I think I have heard that the factor is 3 to 5 times, not twice. But that would skew the equation even further towards the columns remaining rigid.

(I'm not taking credit for this observation. I heard it from another 9/11 truther who knows how to count)

The column factors of safety

were over 3 for the core and over 5 for the perimeter when considering gravity only.

The perimeter columns had more reserve due to having to also handle seismic and wind loads. However there were no earthquakes or high winds on Sept. 11, 2001 so the perimeter reserve was all available for gravity.

14%

Can you or anyone else comment on the statement that the energy carried by the planes and released in the explosion of fuel (he called "gasoline" but I have been lead to believe it is simple kerosene, if there's much of a difference) was equal 14% of that of the Hiroshima bomb?

Now, I'm no physicist or engineer, but there's GOT to be something horribly wrong with that statement. 14% of Hiroshima sounds like a number he picked out of his.,. . well, you know.

hydocarbon fuels have a high energy density

but do not release it nearly as quickly as explosives. Actually gasoline has 15 times the energy density of TNT and chocolate chip cookies have 8 times the energy density of TNT. However, gasoline and chocolate chip cookies do not release their energy anywhere near the one to two millionths of a second that TNT or a nuclear fission weapon do and are not nearly as powerful pound for pound. Power is energy expended per unit time.

The analogy of the jet fuel or gasoline to the Hiroshima nuclear bomb, by Richard Muller, was misguided at best and disingenuous at the worst. You can see in my e-mail to him above that I addressed this issue.

Many, many thanks.

I knew there was SOMETHING suspicious about that concept.