WTC Collapses

maybe this will help explain things:

http://www.youtube.com/watch?v=BA8LWKiOTGI

 

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You stated that Kevin Ryan was 'wrong'. You justify this belief by saying that his job description didn't include structural certification or fire engineering. That's not evidence, that's a conjecture.

Personally, however, I like providing evidence, not conjecture. So I presented you with evidence that demonstrated that he -did- know what he was talking about, providing a long excerpt wherein he details his knowledge of the steel tests that Underwriter Laboratories was performing on behalf of NIST.

 

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Actually, I include rebuttals I've found here and then I debunk them in turn. The problem is that the discussion continues and I haven't updated it in a bit. What this means is that the latest rebuttals to my rebuttals (and my rebuttals to said rebuttals) haven't yet been put in. I'm not sure if I'll continue with it, it takes a fair amount of work to do.

Remember that what inspired me to do it was when I had finished rebutting Kenny's many rebuttals of the Architects and Engineers for 9/11 truth points demonstrating the WTC building collapses were caused by controlled demolitions and then -you- said that it had all been debunked. Loathing the prospect of having to rebut everything all over again, I decided to create the site so that I could just link to it when people claimed that the A&E material was bunk.

So if I find myself loathing the prospect of rebutting something yet again, I may decide to update the site again.

 

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Why dont we have a fiction sub forum? This thread would be perfect there.

 

No one else built a model showing that the behavior of the towers in response to impact would change on the basis of mass and distribution of mass.

http://www.youtube.com/watch?v=z0kUICwO93Q

If you had asked me SEVEN YEARS ago if people would be arguing about this for so long I would have told you, "No way!" But why haven't those people managed to persuade the majority? Why is there so much silence from our engineering schools? I haven't seen anyone else suggest that thought experiment of eliminating levels and computing the effect either.

I don't understand what it takes to settle this since I can't comprehend people believing a plane could do that in that time. Someone would have to PROVE it to me and I would laugh at them if they couldn't supply that information.

I am currently video editing my second demonstration of a collapse which shows that the mass makes a difference.

The problem with that is that it doesn't show how the towers had to be heavier and stronger toward the bottom. Therefore how can it be more likely to convince people that the top could not crush everything below. In less than 18 seconds to be sure.

but it sounds to me like you are judging on the basis of who says what rather than understanding the physics yourself. That is my point. Forget BELIEVING people just understand the grade school physics and figure out the obvious. A skyscraper must support its own weight so it must be stronger and therefore heavier toward the bottom and it had to be documented to be constructed so why can't EXPERTS like the NIST tell everyone things so simple in a 10,000 page report that took 3 years and cost $20,000,000.

They only use the term "center of mass" four times and "center of gravity" six times in 10,000 pages. How did they expect to explain anything? What happened with that "center of mass" of that tilted top of the south tower? We don't know. It ain't there.

psik

 

Yes, I saw that

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. But while I have no quarrel with your argument, I simply feel that it may be an unnecessary one. Yes, it would be good to know this, but the people I mentioned above all believe that there is plenty of evidence even without this. If you were to get in touch with one of them, however, you could always ask them whether they felt how much knowing this information could change things and how to go about getting it.

People still argue about whether Pearl Harbor was an inside job (I believe it was). The argument may go on for a very long time.

I think it has to do with mindsets. If you find it difficult to believe that your government could do such things, then you would probably steer away from people who claim that it would as a general rule. Ironically, I think that forums like this one may well be the key to persuading people of this nature- because they're not being asked to read a book, only a post.. or it starts that way anyway. One post becomes 2, becomes 10, etc. Atleast this is how it happens with certain individuals, such as shaman, kenny and others. I personally find that their arguments keep me relatively sharp. Sometimes when I go onto alternate theory websites I'll see someone come up with an idea and then someone else say 'yeah, sounds good'. And I mean, sure, it sounds good. But I don't see evidence backing it up and I just start thinking, we can't reach conclusions like that. So that's what I like about this forum anyway. You want to make the case for controlled demolition, ok, but you're going to have to make it -very- well because most if not all misteps will be pointed out by people with the opposing view.

Perhaps they took a look at what happened to Steven Jones and decided it would be best to keep quiet on the issue.

Richard Gage, from Architects and Engineers for 9/11 truth did it with some cardboard boxes I believe.

When I first saw the planes crash and the collapses, I bought into the 'plane did it' theory. It seems to me you know a bit more about buildings then your average citizen, so I can understand that you were skeptical.

Cool...

Have you taken a look at this?:
The Number ONE Smoking Gun of 9/11

I can't understand it, but it seems that it makes it clear that the towers had to be brought down by controlled demolition.

I believe I understand enough to know that it was a controlled demolition. When it comes to things that require a fair amount of complicated math, however, I tend to stop understanding it.

I took a grade 12 physics course and passed it if memory serves. I've read a book or 2 from physicists (Steven Hawkins and someone else). But doing these things doesn't mean that physics becomes a breeze. Something that puzzles me; if what you say is indeed so important, why hasn't physicist Steven Jones brought it up?

Your points sound good and it would indeed be nice to know the answers to your questions. However, I'd like to see what you think of the linked page above...

 

So why the bloody hell do you keep posting his letter from years ago?

His opinion is completely irrelevant.

So why do we have to keep going through this? Are you thinking about the links you are spamming?

Who cares? He is not qualified to be an expert on such matters.

Brown was wrong. The official story has never mentioned melting steel. You should know that. Move on.

Read his damn report. Ryan has latched onto the results of the paint samples. Only three of these samples reached temperatures over 250C. However it has been made clear that very few of these came from the impact zone. You will not stop clinging to them though. They are irrelevant, there is more valuable evidence than those.

In the documents I have read, Gayle draws no conclusions and makes no implications that the maximum temperature was a very low 250C.

Which no one believes. Next.

No he wasn’t.

No it isn’t. The jet fuel alone is three times that temperature.

I’m trying to get through to you why that quote is totally irrelevant to the discussion but instead of actually computing what I write you keep spamming the quote as a response!!

Even after so much of what they say has been demonstrated to be utter crap.

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I’m barely keeping my taunts in check at the moment. You post some mindless rubbish from your conspiracy sites, I take the time to point out to you what the problems with it are, eventually you move on or don’t respond at all, then triumphantly you post the same crap a few days later as the definitive proof. When I say we have been through that you respond with “what? when? Point out to me where..” You being intellectual dishonest, obtuse and constant spamming is more provoking than me occasionally using the word “stupid”.

It played a critical role. Saying “almost no role” is no less wrong.

Argh the paint samples again! We have been through the other points there such as the flashover claim.

This is wrong. To demonstrate the errors above, we will use the temperature data from Appendix C of NCSTAR1-5E, which is both representative of an ordinary fire and well suited to the situation in the WTC Towers. Mr. Hoffman here again complains about the “megawatt super-burner,” but the author reminds Mr. Hoffman that the “super-burner” was only active for the first 600 seconds of tests 1, 2, and 4, and the first 120 seconds of tests 3, 5, and 6. Readers may ignore these time periods if desired as they do not affect
our conclusions, listed below:
 Excepting only Test 5, thermocouples in Tree 2 experienced temperatures of over 800 oC for several minutes. In the case of Test 1, the period above 800 oC was over 20 minutes in duration. In tests 2 through 4, instrumentation was damaged by temperatures spiking above 1200 oC – and approaching 1600 oC in Test 2 –making a determination of duration impossible.
 The lone exception, Test 5, was the test of “rubblized” workstations where combustible materials were collapsed, partially buried by ceiling tiles, and not provided additional ventilation. Lower temperatures are expected, but this case still produced gas temperatures of over 600 oC for roughly fifteen minutes.
273
 Thermocouples in Tree 3, located away from the burning workstations and thus less susceptible to damage, reported temperatures above 800 oC for at least ten minutes in all six tests. Readers are reminded that half of these tests involved no jet fuel, just ordinary office materials.
 These results directly contradict Mr. Hoffman’s claim, reprinted above, that temperatures above 800 oC are only produced for “a few seconds.”
R.Mackey

Next week when you post that link again I am going to post this.

That was from my head. Many debunkers have mentioned it. Instead of trying to attack my source, verify it for yourself.

Okay but he wasn’t suggesting that either.

Two different fire tests produced results consistent with those seen in the other examples of steel structures collapsing as well as the simulations. Yes a complete coincidence. Are you really trying to imply that different offices might produce temperatures 750C lower? lol

No the workstation tests.

Were we discussing pancaking?

Were you not aware of this?

http://wtc.nist.gov/pubs/factsheets/faqs_8_2006.htm

“NIST’s findings do not support the “pancake theory” of collapse, which is premised on a progressive failure of the floor systems in the WTC towers (the composite floor system—that connected the core columns and the perimeter columns—consisted of a grid of steel “trusses” integrated with a concrete slab; see diagram below). Instead, the NIST investigation showed conclusively that the failure of the inwardly bowed perimeter columns initiated collapse and that the occurrence of this inward bowing required the sagging floors to remain connected to the columns and pull the columns inwards. Thus, the floors did not fail progressively to cause a pancaking phenomenon.”

The towers lasted twice as long as the Mcormick place and those fires were started with thousands of gallons of jet fuel. Just saying ‘oh but it was a tall steel structure’ doesn’t change the fact that it was vulnerable to fire just as the others were.

The steel part of the Madrid Tower did collapse due to fire! You have decided to avoid reality.

They are ill informed, gullible or dim-witted. The evidence is overwhelming.

I’m using analogies because it is so hard to get through to you and I feel I need them illustrate my point.

Read the FAQ.

 

That's not why he was wrong. He was wrong because the steel temperatures did go over 250C! NIST estimated early on the the temperatures were near 1000C!

Evidence from ill-qualified sources which has already been debunked many times over.

He is not an authority on the matter. In fact NIST say that UL did not even certify the steel in the first place.

 

can you state what you mean by "the temperatures were near 1000C!"

Your arguments are unconvincing because you are being too general with the data. You need to distinguish between atmospheric fire temperatures and steel temperatures. You also need to distinguish between column and floor temperatures, the hottest part in a building fire is likely to be at the top of the ceiling, which the cardington tests show. You cannot equate a ceiling/floor temperature to a column temperature, even the cardington fire tests show these to be wildly different with the column temperatures much lower than the floor temperatures (cardington tests showed the column temperatures were in the low hundreds, half or a third that of the floor temperatures). Just saying "1000C" is misleading because it looks like you are trying to convince people that the core columns reached those temperatures which won't help your argument. You are exagerating the temperatures from a test which actually showed the floor systems did not fail!

You are also quoting mackey saying 1600C?? where did that come from? does he mean Fahrenheit, or is this anomalous data, flashover termperature? again simply throwing out a number without context is pseudoscience.

I think you are confusing fascism with science.

<groan> UL certified the steel floor assemblies!
surely you see the misleading nature of the statement "UL did not certify the steel" ?
The steel is a component of the steel floor assemblies!!
To quote Ryan himself "This is a bit like saying we don't crash test the car door, we crash test the whole car."

edit - oops, its "Cardington" not "Cardigan"

http://www.mace.manchester.ac.uk/pr...ures/strucfire/DataBase/TestData/default1.htm

http://wtc.nist.gov/pubs/NISTNCSTAR1-5Draft.pdf

 

I am generalizing a little here but there are two things to consider. 1. I am refuting Scott’s confusing claims that NIST did not think the fire (or the steel) went over 250C.

2. I have spend a bit of time in the other thread referencing the Cardington fire tests (I believe Kenny linked to some others) where the temperature of unprotected steel was only marginally below that of the atmospheric temperature.

I don’t know if the data exists to be that accurate when discussing WTC. Keep in mind though that the fires were across many floors.

The columns in the Cardington structure were insulated and did not have the long-span construction of WTC.

I didn’t notice that. I assume it is a mistake. A mistake that 911research also made when they reported temperatures of 7500C!
http://911research.wtc7.net/mirrors/guardian2/fire/cardington.htm

I don’t know much about this one and am only reading up on it as I type this. I think the comment that the steel was certified by UL would still be incorrect though. Scott did say that on page 3.

Mackey makes a few points about this. One of them is worth noting.

The fire rating only applies to the complete structural system, which includes, in particular, undamaged fireproofing material. Therefore, after an aircraft impact which damaged the fireproofing, the rating is no longer valid.

I see your point though.

Oh come on he was a chemist who worked in environmental testing. Scott keeps referring to his opinions on the temperatures of the fire. It is a confused appeal to authority.

 

What temperature did the columns reach in the cardington tests?
if you don't know the data off the top of your head, you can find it by clicking here and follow the column links: 4D,4E,4F,3E
http://www.mace.manchester.ac.uk/pr...trucfire/DataBase/TestData/BRETest/page47.htm

In the Cardington test 4 there is no fireproofing or insulation on either beams or columns. if i am incorrect on this then please show your proof. I don't know the significance of the "long span" construction of the wtc, i would suggest that would weaken your argument, rather than strengthen it.

you can listen directly to Kevin Ryan on the subject, it is covered in the first few minutes:
http://mp3.wtprn.com/Brouillet/0805/20080526_Mon_Brouillet1.mp3

NIST experiments firing a shotgun at fireproofed steel actually did not damage the fireproofing. So Mackey repeats NISTs assumption. There is no argument that it was not damaged - of course it would have been damaged to an extent, but the relevent question is was it damaged enough to significantly to affect the fire rating of the structure. Moot point anyway if we are looking at test data with zero fireproofing which assumes conditions as favourable to your argument as possible.

The argument is whether UL certified the steel assemblies and the fire rating of the assemblies, which NIST say they did not (obviously they did not want the test data revelaved which would have contradicted their own report), and Kevin Ryan said they did certify the steel and the fireproofing. The argument is is not about Kevin Ryan's credentials, but if you bring it up make sure you get it right - he worked as a lab manager for many years, which is a pretty senior and experienced position, and had scientific training in chemistry.
http://mp3.wtprn.com/Brouillet/0805/...Brouillet1.mp3

 

Not a valid comparison. :shrug:

There was nothing about Pearl Harbor that had to violate any laws of physics in order for the official story to be true. That was only a case of possibly secretive human behavior and probably something that can never be proven with 100% certainty. There just happens to be A LOT of suspicious circumstantial evidence.

Some minimum of steel had to be on every level of the WTC for it to stand and withstand the wind for 28 years. The Empire State Building is proof that this is an area of knowledge where there has to be sufficient expertise. How many people were thinking about landing on the moon when the ESB was completed, 38 years before the actual landing? Now we can't solve something this simple 39 years after the landing.

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They are both Newtonian physics problems. This is PATHETIC!.

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psik

 

It seems to me there's enough evidence to indict FDR personally. However, I agree that no laws of physics needed to be broken in the official Pearl Harbor story.

Life can at times have down times. I believe the reason more people haven't investigated issues concerning 9/11 is that they're too concerned with their own lives. And the people who were paid to investigate 9/11 did it under restrictive circumstances or, in some cases, may well have been in on the deception themselves. You could say they were selling the official story. Gene Corley seems to have worked overtime in that role. Kevin Ryan has written a fair amount on this in his article Propping Up the War on Terror:
**********************************
Selling the Official Story: Some Key Players

Shankar Nair, whose statement quoted above is quite telling, was one of those "experts" on whom the government depended to support what turned out to be an ever-changing, but always flimsy, story. Many of the scientists involved in the investigation were asked to examine ancillary issues, like escape routes and other emergency response factors. But those few who attempted to explain what really needed explaining, the unique events of fire-induced collapse, appear to have engaged in what can only be called anti-science. That is, they started with their conclusions and worked backward to some "leading hypotheses."
Not surprisingly, many of the contractors who contributed to the NIST investigation, like the company for which Nair works, just happen to depend on good relationships with the government in order to earn their living. What may be a surprise is just how lucrative these relationships can be. For example, Nair's company, Teng & Associates, boasts of Indefinite Quantity Contracts, long-term relationships with federal government agencies, and federal projects worth in excess of $40 million.6

Others who worked so hard to maintain the official story included Gene Corley, a concrete construction expert listed by the National Directory of Expert Witnesses as a source for litigation testimony.7 Corley was more than just a witness, however. He had led the Oklahoma City bombing investigation and then was asked to lead the initial ASCE investigation into the WTC disaster. Perhaps someone else, with less experience in bombings and more experience in fires, would have been a better choice. But without authority to save samples or even obtain blueprints, the ASCE investigation was ineffective anyway. Corley himself ended up being a very versatile resource, however, providing testimony supporting the pre-determined conclusions many times, and even posing as a reporter during an NIST media session.8

There was really no need for phony media coverage. As with The 9/11 Commission Report and the lead-up to the Iraq War, the major media simply parroted any explanations, or non-explanations, given in support of the official story. One example is from a television program called "The Anatomy of September 11th," which aired on the History Channel. Corley took the lead on this one as well, but James Glanz, a New York Times reporter, was also interviewed and helped to spread what is probably the worst excuse for collapse given. He told us that the fires heated the steel columns so much (the video suggested 2500 F) that they were turned into "licorice." Other self-proclaimed experts have been heard promoting similar theories.9 They will probably come to regret it.

This is because the results of physical tests performed by NIST's own Frank Gayle proved this theory to be a ridiculous exaggeration, as some people already knew. The temperatures seen by the few steel samples saved, only about 500 F, were far too low to soften, let alone melt, even un-fireproofed steel. Of course that result could have been calculated, knowing that 4,000 gallons of jet fuel10 ---not 24,000 gallons or 10,000 gallons, as some reports have claimed---were sprayed into an open-air environment over several floors, each comprised of more than 1,000 metric tons of concrete and steel.

Another expert who served on NIST's advisory committee was Charles Thornton, of the engineering firm Thornton and Tomasetti. Thornton's partner, Richard Tomasetti, was reported to be behind the unprecedented and widely criticized decision to destroy most of the steel evidence.11 Early on Thornton said: "Karl, we all know what caused the collapse." He was talking to Karl Koch, whose company erected the WTC steel. Koch attempted to clarify as follows. "I could see it in my mind's eye: The fire burned until the steel was weakened and the floors above collapsed, starting a chain reaction of gravity, floor falling upon floor upon floor, clunk – clunk – clunk, the load gaining weight and momentum by the nanosecond, unstoppable. Once enough floors collapsed, the exterior walls and the core columns were no longer laterally supported and folded in."12 This is a description of what was called the Pancake Theory, the most widely accepted version of what happened.

The Pancake Theory was promoted by an influential 2002 NOVA video called "Why the Towers Fell," in which Corley (yet again) and Thornton were the primary commentators. Both of them talked about the floors collapsing, and Thornton described how the perimeter columns buckled outward, not inward as Koch had described. The video made a number of false claims, including exaggeration of the temperatures (2000 F), remarks about melting steel, and the incredible statement that two-thirds of the columns in WTC1 (the North Tower) were completely severed. NIST's report now indicates that only about 14% of the columns in WTC1 were severed, and in some photos we can count most of these for ourselves.13
**********************************

 

ROFLMAO

I never had any intention of reading the entire 10,000 page NCSTAR1 report. I just downloaded it so I could more quickly search it for what I thought had to be important in analyzing the event. A couple of things I searched for were "center of mass" and "center of gravity". At the time I was particularly interested in the "center of mass" of the south tower because of that tilt of around 20 degrees. That should have fallen down the side. Why didn't it?

But anyway, I only found four instances of the use of "center of mass" and they were all in a report about the effect of shock on suspended ceilings. So I was wondering why the hell would they study that. But it turns out that that report has is the only mention of the need to know the distribution of mass in order to analyze the effect of the impact. So it seemed very strange to me that a report on an idiotic subject would also have such competent information in it. The "center of mass" is in reference to the airliner. It is the only REAL object in the entire report that center of mass refers to. The 6 places where they use "center of gravity" refer to computer simulation components. So it did look to me like the competent, conscientious people got shuffled off to doing trivial bullshit. But they still stuck some gems of relevant information in there.

Most of that report is time wasting but complicated trivia. A big expensive snow job.

psik

 

If we are talking about the same tests you are incorrect.

In one of the tests, a small part of the columns were unprotected. However the steel softened and buckled so in all the remaining tests the columns were completley protected.

“800mm of the columns including the connections were also unprotected. The supporting columns were squashed by 180mm (pictured in Figure 4.4) at unprotected column temperatures of 670°C.197 As a direct result of this squashing all further tests had protected columns to the underside of the slab.”
http://911research.wtc7.net/mirrors/guardian2/fire/cardington.htm


The document Behaviour of Steel Framed Structures Under Fire Conditions also confirms this. The pdf I have is all an image though, it doesn't recognize the text.

This is relevant to the temperatures mentioned in your first paragraph as well.

The theory is that the long span trusses are more susceptible for fire.

I read that there was some damage. The argument was regarding the extent.

There was much steel recovered which was stripped of it’s fireproofing but there is always the problem of determining if it happened before or after collapse. I believe the photographs of the impact areas gave indication of stripped fireproofing.

Scott has repeatedly mentioned Ryan’s opinion on the temperatures of the fires (or was it steel). I am just trying to make it clear that Ryan’s opinion is not evidence.

Yes I know, I have mentioned that before.

.. and that makes him an expert on fires in high rise office buildings?

He did not even work in the area which tested the assemblies. He was in environmental testing, on water I believe.

 

You focus on his job description and degrees, not on the man himself. At times, what is needed when it comes to taking on officialdom is not established credentials but the willingness to investigate things on one's own time and the -courage- to bring up politically dangerous issues. It's clear from articles like Propping Up the War on Terror that Kevin Ryan had both of these qualities and for that he was fired.

 

Debris doesn't make a building collapse demolition style, no matter where it came from.

Some steel structures, sure, but not steel framed high rises, sorry.

Due to explosives, yes.

If so, they put the explosives a bit higher then the bottom. It doesn't change much.

As Headspin said in another forum:
***********************************
people seem to forget there were many reports of witnesses reporting explosions and bombs before and during the towers "collapse" - firefighters, journalists, police, first responders, workers in the buildings, people on the scene etc. Also reports of bombs in the building and at the world trade centre prior to collapse
***********************************

Here's a good video with such supporting evidence, check it out at about 1:40:
http://video.google.ca/videoplay?do...&ei=VrclSfe0FKGI-gGe6KnwBg&q=WTC 7 demolition

Leave perfection to the gods. Even a demolition expert has said that it had "absolutely" been imploded:
http://www.youtube.com/watch?v=k3DRhwRN06I

Ofcourse, said demolition expert doesn't live in the U.S. and thus didn't have to deal with the type of political fallout that would have occured had this been the case.

Not addressing something doesn't mean I have ignored it; you simply hadn't brought it up before. I will look into this.

Again, I will look into this one.

Yes, the final nail in the official story. How did they know it was going to collapse? Architects and Engineers for 9/11 Truth founder Richard Gage makes it clear just how damning for the official story that is in this video.

 

Well you haven't answered one of the questions which disproves the entire story of demolitions in the towers. There was no bulls eye on the tower.

You see, the explosives were, in your arguement, placed in the direct area where the airplane hit. Nowhere else, because than if the explosives were, lets say 10 stories lower, it would be incredibly obvious that the planes didn't take out the tower, the explosives did. The only way for the explosives to have been as subtle as possible is for the plane to hit the exact spot.

A normal passenger plane is moving at around 400 mph, around the area of 600 feet per second, that's pretty fast wouldn't you say so? If the pilot and co pilot had above average sight abilities they would be able to accurately count the number of floors at a range of around 100-300 feet away from the tower. Now if the plane is moving at around 600 feet per second than that means that the pilot or co pilot have around 1/2 to 1/6 of a second to not only count the number of stories on the building, but to also redirect and change the altitude to hit them.

On top of that these guys probably poured on full throttle for maximum impact meaning the plane could realistically be going around the area of 550 miles per hour or more, which translates to 775+ feet per second. Meaning that realistically speaking the pilots had even less time to perform this feat.

So in effect it would be impossible for the pilots to not only count that many levels of the building but to change the altitude of the plane.

 

9/11 Research answers this on its Frequently Asked Questions: Controlled Demolition page:
**************************************
•How could charges have been pre-positioned in the Towers in such a way that the plane crashes and fires wouldn't have set them off?

There are several possible answers to this. First, some charges may indeed have been set off by the crashes but masked by the huge fireballs created by the combustion of aerosolized jet fuel. Second, the charges could have been arranged so as to avoid the regions that the attack planners expected to take direct hits from the aircraft. Assuming that the jetliners were being flown by autopilot at the times of their impacts, the GPS navigation systems could have kept the targeting error margin to within a few feet. Third, explosives can be engineered so that heat alone will not detonate them. The plastic explosive C4, for example, requires the simultaneous delivery of high heat and pressure to induce detonation. Fourth, it is relatively easy to design casings for explosives that would allow them to survive even the most violent assaults. Consider that the black boxes that store aircrafts' voice and data recorders protect their contents from impact accelerations of 3,400 Gs and from temperatures of 2,000 F for up to 30 minutes.
**************************************

 

I went looking for an answer to this. I didn't find any of the big names (Steven Jones, Kevin Ryan, David Ray Griffin, 9/11 Research) saying anything on this, but I -did- find this:
**************************
9/11 was a master plot, concocted by a handfull of Israelis and dual passport Americans and carried out by the resources of the Mossad. Larry Silverstein buys a nearly worthless WTC building complex (worthless due to the asbestos the buildings were stuffed with and needed to be cleaned up, the cost of which may have rivaled the value of the buildings themselves) weeks before 9/11, makes sure it is over-ensured against terrorist acts, tellingly with a german ensurer, next hires an israeli security firm and in the weekend before 9/11 cuts off power in all the WTC buildings with 'maintenance' as an excuse, so the buildings are virtually empty. At that moment the coast is clear to let a team of demolition experts from the israeli army led by Peer Segalovitz into the WTC buildings. These charges plus detonators had been prepared at the premises of the Urban Moving Systems company, a Mossad front. During this weekend these prepared charges were loaded into vans, driven into the basement of WTC next to the elevator shaft, unloaded into the elevator, and lifted onto the roof of the elevator through the openening in the elevator ceiling. Next the elevator moved from floor to floor while charges where being attached to the columns as displayed in this video from 0:22 onwards[I saw no video at this part of the text].The detonators of these charges were radio controlled and finally detonated from WTC7 on the day of 9/11.
**************************
http://able2know.org/topic/125237-1

Plucked from a similar question regarding the twin towers, I got this from 9/11 research:
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explosives can be engineered so that heat alone will not detonate them. The plastic explosive C4, for example, requires the simultaneous delivery of high heat and pressure to induce detonation.
*************************