Another Engineer Questions WTC Collapses

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U.S. engineer William Rice questions the collapses of the World Trade Center buildings. The Vermont Guardian has the goods.

Why the towers fell: Two theories

By William Rice

Posted March 1, 2007

Having worked on structural steel buildings as a civil engineer in the era when the Twin Towers were designed and constructed, I found some disturbing discrepancies and omissions concerning their collapse on 9/11.

I was particularly interested in the two PBS documentaries that explained the prevailing theories as determined by two government agencies, FEMA and NIST (National Institute of Science and Technology). The first (2002) PBS documentary, Why the Towers Fell, discussed how the floor truss connectors failed and caused a “progressive pancake collapse.”

The subsequent 2006 repackaged documentary Building on Ground Zero explained that the connectors held, but that the columns failed, which is also unlikely. Without mentioning the word “concrete,” the latter documentary compared the three-second collapse of the concrete Oklahoma City Murrah Federal Building with that of the Twin Towers that were of structural steel. The collapse of a concrete-framed building cannot be compared with that of a structural steel-framed building.

Since neither documentary addressed many of the pertinent facts, I took the time to review available material, combine it with scientific and historic facts, and submit the following two theories for consideration.

The prevailing theory

The prevailing theory for the collapse of the 110-story, award-winning Twin Towers is that when jetliners flew into the 95th and 80th floors of the North and South Towers respectively, they severed several of each building’s columns and weakened other columns with the burning of jet fuel/kerosene (and office combustibles).

However, unlike concrete buildings, structural steel buildings redistribute the stress when several columns are removed and the undamaged structural framework acts as a truss network to bridge over the missing columns.

After the 1993 car bomb explosion destroyed columns in the North Tower, John Skilling, the head structural engineer for the Twin Towers, was asked about an airplane strike. He explained that the Twin Towers were originally designed to withstand the impact of a Boeing 707 (similar in size to the Boeing 767). He went on to say that there would be a horrendous fire from the jet fuel, but “the building structure would still be there.”

The 10,000 gallons of jet fuel (half capacity) in each jetliner did cause horrendous fires over several floors, but it would not cause the steel members to melt or even lose sufficient strength to cause a collapse. This is because the short-duration jet fuel fires and office combustible fires cannot create (or transmit to the steel) temperatures hot enough. If a structural steel building could collapse because of fire, it would do so slowly as the various steel members gradually relinquished their structural strength. However, in the 100-year history of structural-steel framed buildings, there is no evidence of any structural steel framed building having collapsed because of fire.

Let’s assume the unlikelihood that these fires could weaken all of the columns to the same degree of heat intensity and thus remove their structural strength equally over the entire floor, or floors, in order to cause the top 30-floor building segment (South Tower WTC #2) to drop vertically and evenly onto the supporting 79th floor. The 30 floors from above would then combine with the 79th floor and fall onto the next level down (78th floor) crushing its columns evenly and so on down into the seven levels below the street level.

The interesting fact is that each of these 110-story Twin Towers fell upon itself in about ten seconds at nearly free-fall speed. This violates Newton’s Law of Conservation of Momentum that would require that as the stationary inertia of each floor is overcome by being hit, the mass (weight) increases and the free-fall speed decreases.

Even if Newton’s Law is ignored, the prevailing theory would have us believe that each of the Twin Towers inexplicably collapsed upon itself crushing all 287 massive columns on each floor while maintaining a free-fall speed as if the 100,000, or more, tons of supporting structural-steel framework underneath didn’t exist.

The politically unthinkable theory

Controlled demolition is so politically unthinkable that the media not only demeans the messenger but also ridicules and “debunks” the message rather than provide investigative reporting. Curiously, it took 441 days for the president’s 9/11 Commission to start an “investigation” into a tragedy where more than 2,500 WTC lives were taken. The Commission’s investigation also didn’t include the possibility of controlled-demolition, nor did it include an investigation into the “unusual and unprecedented” manner in which WTC Building #7 collapsed.

The media has basically kept the collapse of WTC Building #7 hidden from public view. However, instead of the Twin Towers, let’s consider this building now. Building #7 was a 47-story structural steel World Trade Center Building that also collapsed onto itself at free-fall speed on 9/11. This structural steel building was not hit by a jetliner, and collapsed seven hours after the Twin Towers collapsed and five hours after the firemen had been ordered to vacate the building and a collapse safety zone had been cordoned off. Both of the landmark buildings on either side received relatively little structural damage and both continue in use today.

Contrary to the sudden collapse of the Twin Towers and Building #7, the four other smaller World Trade Center buildings #3, #4, #5, and #6, which were severely damaged and engulfed in flames on 9/11, still remained standing. There were no reports of multiple explosions. The buildings had no pools of molten metal (a byproduct of explosives) at the base of their elevator shafts. They created no huge caustic concrete/cement and asbestos dust clouds (only explosives will pulverize concrete into a fine dust cloud), and they propelled no heavy steel beams horizontally for three hundred feet or more.

The collapse of WTC building #7, which housed the offices of the CIA, the Secret Service, and the Department of Defense, among others, was omitted from the government’s 9/11 Commission Report, and its collapse has yet to be investigated.
Perhaps it is time for these and other unanswered questions surrounding 9/11 to be thoroughly investigated. Let’s start by contacting our congressional delegation.

William Rice, P.E., is a registered professional civil engineer who worked on structural steel (and concrete) buildings in Boston, New York, and Philadelphia. He was also a professor at Vermont Technical College where he taught engineering materials, structures lab, and other building related courses.

Thanks to Prison Planet for the heads up!

Tearing it DOWN

One false brick at a time!!!
Ignorance is NOT Bliss

Show "New evidence" by tims

ooohhhh, i think we have a

ooohhhh, i think we have a professional here. welcome tims. whats your motivation? just wondering....

Wonderful article -- simple,

Wonderful article -- simple, straightforward, layman-friendly. I hope this emboldens others in his field to come out.

The publicity from the Vermont Ballot Initiative must have influenced his decision to write the article. Goodonya, Vermont!

Simplicity is the key.

When I have sat down with family, friends, or collegues who still abide by the myth of 9/11 (and the "C"ommission Report) I often lack the means of putting it into simple, common, every-day language.

This article is a decent disucssion starter. It should be circulated ad nauseum.

This engineer is taking a great risk. I can't help but think to the immediate weeks after 9/11 when a professor of architectural engineering from NYU (who happens to be a familky acquaintance) said he "couldn't believe how those towers came down." We all thought he meant it in the greater, geo-political sense of the question. But what he really was getting at was a question of science.

The path for 9/11 Truth must be based in sound, simple science.

This is what will bring about the Tipping Point.

Structural Engineers for 9/11 Truth

We MUST try to get mr Rice to establish Structural Engineers for 9/11 Truth.

By the way, this article now has a whopping 2059 diggs:

I wonder how long they can keep it from the front page...


Send this out to evidence websites.

70 Disturbing Facts About 9/11

John Doraemi publishes Crimes of the State Blog

johndoraemi --at--

It All Looks Like Old News To Me...

but it's nice to have another one on our side.
Vermont and New Hampshire are always good states in terms of political output.

Speaking of

Also, I bought votes on

These digg-related stories are well worth the time to peruse

as well as the Wired story below.

One person captured about 1700 buries, including user names and reason for bury. (Digg Spy shows buries, but anonymously.) Of those, about 24 were buries of the BBC story that were *NOT* buries a user attributed to the story's duplication.

Users who buried one (or both) of two BBC articles

because it was "spam": registration11, bnajbert, glenjammin

because it was "inaccurate": adm58, saintdogbert, tsunamisteve, ahsen74, mooseblaster, glenjammin, raitchison, andyboyd, fooplex, badger80

and my favorite, because "ok, this is lame": tonage, registration11, kylesellers, willis77, geekchic, mbierman, bem1, meltingrobot, glenjammin, fooplex

Wired is picking up on

This story is on diggs front

This story is on diggs front page right now. Maybe they fixed whatever problems they were having.

9000 x 9000 ground zero arial shot.

Also from DIGG- A hi res 9000 x 9000 ground zero arial shot...huge!

American Buddhist

American Buddhist Net is also carrying this piece.

They also have quite a bit of other 9/11 material.

Great Piece from Wired

Digg is a complete fraud.
It's just another simulated democratic space--always the best way of keeping slaves thinking they're free.

Does anyone have contact

Does anyone have contact info for William Rice?

Isn't he a civil engineer...

rather than a structural engineer?

from Wikipedia: "Civil engineering is a broad field of engineering dealing with the planning, construction, and maintenance of fixed structures, or public works, as they are related to earth, water, or civilization and their processes. Most civil engineering today deals with power plants, bridges, roads, railways, structures, water supply, irrigation, the natural environment, sewer, flood control, transportation and traffic.

Civil engineering is the broadest of the engineering fields, partly because it is the oldest of all engineering fields.

Structural engineering is concerned with the structural design and structural analysis of buildings, bridges, and other structures. This involves calculating the stresses and forces that act upon or arise within a structure, and designing the structure to successfully resist those forces and stresses."

I think this should be corrected. I think we should be 100% accurate.

I agree please fix this

Please fix this, since the first sentence clearly says he is a civil engineer not a structual engineer.

From Wikipedia: "In building

From Wikipedia: "In building construction, the structural engineering field is a subset of civil engineering. "

I think it is ok as is.

Support those promoting the truth with rational messages!

I think it's a good thing that we present a "9/11: Press for Truth-esque" objective approach to the facts instead of saying "you're a sheep" if you don't believe the theories or "you're a nut" if you do. So in keeping up with my rational letters of support to those helping to expose the truth...

"Thanks for publishing the article by William Rice on the WTC. I don't believe that explosives took down the towers but I don't believe necessarily that fires from the planes did either. Basically I'm agnostic on the issue pending a real investigation. I do have to say that the case of WTC7 is damning evidence of a controlled demolition that is hard to refute. I find it beyond intriguing that NIST has yet to produce their report on WTC7's collapse and that they are considering controlled demolition as a hypothesis.

Anyway, please keep up the good work of independent media. Awesome job!"

Well said.

What we are doing is beginning to work.

I think that people will follow your advice here. We can see that it brings results.

Although, to tell the truth, I couldn't bring myself to say that "I don't believe that explosives took down the twins." I do believe that, and would not lie on that topic. (Yet it always helps to write calmly and rationally, no matter what we say. That's what I was agreeing about, the tone of your letter. That, and the emphasis on WTC 7. Somehow, the disinfo on WTC 1 & 2 is mostly just too pervasive to crack, at present. Regardless of how obvious the case is.)

(And look: there is such a long ways to go, isn't there. Did everyone see the comments to this article? Such certainty, with jokes, about how gravity was the cause of collapse and so on. Implied: truthers are idiots.)

An excellent testimony for a 911 trial witness.

While I was reading this very good and clear document I had the impression I was reading someone speaking in court. It's the kind of thing we need to bring Bush down in front of the law.


Bring them to justice.

Bring them to justice.



Lets reclaim the language around these events. Having concise , lay articles like this is a step in the right direction. Let's make Controlled demolition and Building 7 'household words. I guess we can thank the BBC for help with that too.

$20 000 Question

What is this explosion? Is it generally accepted that a secondary explosion collapsed part of that wing of the pentagon?

from a Digger...

  1. [comment buried, show comment] - 1 digg bury this digg this
    This man makes numerous errors.
    1) The WTC towers were NOT steel frame. They used steel, but they were NOT steel frame structures. The primary load-bearing structure was concrete with a slight twist in design in that the weight of each floor was primarily supported by the inner "core". This invalidates part of his argument.

    2) He says:

    "The interesting fact is that each of these 110-story Twin Towers fell upon itself in about ten seconds at nearly free-fall speed. This violates Newton’s Law of Conservation of Momentum that would require that as the stationary inertia of each floor is overcome by being hit, the mass (weight) increases and the free-fall speed decreases."

    Very wrong. If the "frictional force" (of stationary floors) is less than the force of impact, then each successive floor would accelerate. If each successive floor that is broken loose accelerates you get an increasing momentum due to picking up more mass from the previous floor that gave way and more speed due to acceleration. The process feeds on itself. Each failed floor means more mass and more speed. This means more momentum because momentum is mass*velocity. At some point the momentum of all the floors that are falling is so much that the inertia of the stationary floors is but a tiny fraction of the falling floors. This means free-fall.

    Each floor was concrete, and no floor was designed to withstand the momentum of the floor above it from hitting it. Now, assume several floors are destroyed by a massive impact and then we have quite a distance for a floor to fall before impacting the next one. It is very plausible that it only took two or three of these floors gone for the collapse to look like free-fall.


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This is simply false.

"The WTC towers were NOT steel frame. They used steel, but they were NOT steel frame structures. The primary load-bearing structure was concrete with a slight twist in design in that the weight of each floor was primarily supported by the inner "core". This invalidates part of his argument."

They were indeed steel-frame structures, in which the load-carrying capacity was provided by BOTH a exterior steel columns and a steel core. Give me a freakin' break.

steel frame structure

This is what cracks me up about people's misconceptions regarding the towers' construction. They either lie like the guy quoted above, or they say something like--it was a unique design, so it couldn't have been predicted!

When you get down to it though, the twin towers'core structures were essentially a building surrounded by the perimeter columns forming a cage around it. So if anything, the twin towers were buildings with two lines of defense as it were. The perimeter columns absorbed the brunt of the impacts leaving the core columns with much less damage than if they had been hit directly. Given the fact that not only could the load shift from the broken exterior columns to the undamaged ones but also to the cores, the slight raising of the temperature of the structure in the impact zone simply precludes the type of collapse we observed, which would require simultaneous failure of all of the 57 core and 236 or so exterior columns.


Real Truther a.k.a. Verdadero Verdadero - Harvard Task Force


For sheer accuracy:

47 core, 236 perimeter and 4 perimeter corner columns.

That theory got abandoned, but remains out there anyway

Isn't it the case that NIST itself has abandoned the 'pancake' theory, which is championed in this comment on the article?

The terrible conundrum of a pancake-pile-driver, of top floors, crushing the floors underneath itself, somehow getting puverized -- but by what? -- on landing, sort of wrecks that thesis, right? Although I am not an engineer so what do I know...

47 column "core"

I'm no engineer but how does that explain how the massive metal core was reduced to convenient transportable chunks?

Free fall is not mass dependant

Thus, any time difference from absolute free fall in air, which is somewhere between 10 and 12 second for that height, depending on the mass to surface area ratio, is the only available alloted time frame within which every single weld and joint would have to fail, along the entire remaining length of structure, in this case, about a mere second, or two.

One two.

Furthermore, according to the law of intertia, an object in motion will tend to remain in motion UNLESS ACTED UPON BY A FORCE OF RESISTANCE.

Additionally, the buildings just peeled away, in a fountain like cascade of debris ejection, from the top down, where a vast amount of the building mass would have been offloaded throughout the descent, and so it's a little disingenuous to say that there was this floor on floor cumulative weight loading in some sort of pancake collapse, when that is not what is actually observed to have occured at all.

Under a "gravity collapse" scenario

how could one possibly account for steel beams being hurled upwards and outwards?

Why were the concrete floors etc. reduced to powder and small rubble rather than breaking into large rebar reinforced pieces.

These two phenomena cannot be explained by any "gravity collapse" formulation.

Momentum tutorial

If a moving billiard ball hits a stationary billiard ball, then the resulting speeds they will travel at has to be less than the speed that the first ball was traveling at. That's because momentum = velocity X mass , and the momentum of a system must stay the same, e.g. "is conserved." So if you increase the mass (two balls instead of one), then the velocity must decrease.

Therefore, even if it took zero force (in other words, suppose it was just "floating" there with no support or connectors at all, waiting for something to hit it, which of course was not the case) and no delay for a succeeding floor to start to move after being hit by the floors above it , then the new floor's mass must cause the whole system to slow down. The actual calculations are complicated by the constant acceleration of gravity, but, nevertheless, the falling floors would be slowed down some each time they hit a floor below. People with much more skill than I have calculated the minimum time, that is, if no resistance at all were offered, and found it to be considerably longer than free-fall speed, perhaps 30 or 40 seconds. And, of course, the floors offered considerable resistance, so much so that the combination of the resistance and "conservation of momentum" likely would have stopped the collapse after a few floors.

This site, which I found after a 4 minute search, explains it in detail.

Fred W

This is Significant

Having someone in the Engineeing field question the official hypothesis adds enormous credibility to the right side of this issue. We must ask ourselves how much longer people's cognitive dissonance can persist.

My younger bother (11 mo.) holds a Master's degree in Civil Engineering and has worked as a registered P.E. for close to twenty years. While visiting/working with me over two years ago, I asked him if he had ever considered an alternative hypothesis to the destruction of the World Trade Center buildings. He told me that the Professor in charge of his Master's degree course had made a suggestion to the students to find the loading required to bring about the catastrophic collapse witnessed in WTC 1&2. He even had CD's containing the buliding plans.This was to be done as a thesis, the most important part of the curriculum. Interestingly, the Professor was a Pakistani national (my brother told me this when I suggested he take the suggested thesis, as the professor was going to be in Pakistan for three months and would return when the thesis were complete).

Anyway, after showing my brother clips of WTC 7, he said "yeah, it kinda does resemble controlled demolition. How do you think the terrorists could get explosives in the building without anyone noticing?"

It was then I realized that different people have different capacities for recognizing deception. It's not an intelligence issue, which is hard sometimes for those who know the truth to grasp, but time is on our side.

Attn: 9/11 Bloggers--Please forward the following key message

to Alex Jones at and/or

Who gave left-gatekeeper Amy Goodman the foreknowledge that WTC-7 was going to implode???

Near the end of the brief video linked below, Goodman is clearly shown waiting for the controlled demolition of WTC-7!!! As it is brought down, Goodman runs through the crowd exclaiming, "Oh God!"

So who gave the African-American cop, Amy Goodman, and all the other people watching WTC-7 the foreknowledge that WTC-7 was going to be brought down in a controlled demolition???

Why has Goodman never revealed that she was an eyewitness to this outrageous crime???


I have been trying for over an hour to send this info to Alex & his team, but I'm getting all sorts of dubious error messages preventing me from doing so! Either Alex's sites or my connections are being blocked/sabotaged!

Thank you very much.

I don't see it...

Every time I see this clip, I wonder where people are seeing Amy Goodman. How do you know she was the one yelling, "Oh my God!"?

That is Goodman running through the crowd near the end of the

clip. She has long stringy hair, and is wearing a gray outfit. I used to watch her gatekeeping, disinformation show, "Democracy Now" on public access tv every day, and I easily recognize her appearance and her voice.