Self selection in conspiracy theorists

[_mikwut]

Lemmie,

I was addressing Markk's horseshoe example, maybe melt is incorrect for that I'm not sure? But from what NIST and the paper I posted state the temperatures were only 1000 C for 15 minutes and hovered at 500C otherwise. That isn't enough for the weakening.

mikwut

[Guest]

From the NIST website:

6. What caused the collapses of WTC 1 and WTC 2?

Based on its comprehensive investigation, NIST concluded that the WTC towers collapsed because: (1) the impact of the planes severed and damaged support columns, dislodged fireproofing insulation coating the steel floor trusses and steel columns, and widely dispersed jet fuel over multiple floors; and (2) the subsequent unusually large number of jet-fuel ignited multi-floor fires (which reached temperatures as high as 1,000 degrees Celsius, or 1,800 degrees Fahrenheit) significantly weakened the floors and columns with dislodged fireproofing to the point where floors sagged and pulled inward on the perimeter columns. This led to the inward bowing of the perimeter columns and failure of the south face of WTC 1 and the east face of WTC 2, initiating the collapse of each of the towers. Both photographic and video evidence—as well as accounts from the New York City Police Department aviation unit during a half-hour period prior to collapse—support this sequence for each tower.

14. How did NIST derive the temperatures in the WTC towers and how valid are they?

Using all the visual and physical evidence available, NIST conducted simulations of the fires in each of the towers from the time of airplane impact to the collapses. The computational model used to simulate the fires was NIST's Fire Dynamics Simulator (FDS). This model had been validated in numerous experiments and fire recreations prior to the NIST WTC investigation. Additional large-scale experiments conducted during the investigation (NIST NCSTAR 1-5) provided further assurance of the validity of the model output. This output was in the form of maps of the air temperatures on each of the floors over the duration of the fires (shown in NIST NCSTAR 1-5F).
In a following set of computations, the evolving temperatures of the concrete and steel structural components of the towers were calculated by exposing them to the mapped air temperatures (shown in NIST NCSTAR 1-5G).

Both sets of computations are based on the fundamental laws of combustion, heat transfer, and air flow. The methods have been documented extensively and have been successfully subjected to technical peer review and published in professional journals.

15. Since the melting point of steel is about 1,500 degrees Celsius (2,800 degrees Fahrenheit) and the temperature of a jet fuel fire does not exceed 1,000 degrees Celsius (1,800 degrees Fahrenheit), how could fires have impacted the steel enough to bring down the WTC towers?

In no instance did NIST report that steel in the WTC towers melted due to the fires. The melting point of steel is about 1,500 degrees Celsius (2,800 degrees Fahrenheit). Normal building fires and hydrocarbon (e.g., jet fuel) fires generate temperatures up to about 1,100 degrees Celsius (2,000 degrees Fahrenheit). NIST reported maximum upper layer air temperatures of about 1,000 degrees Celsius (1,800 degrees Fahrenheit) in the WTC towers (for example, see NCSTAR 1, Figure 6-36).
However, when bare steel reaches temperatures of 1,000 degrees Celsius, it softens and its strength reduces to roughly 10 percent of its room temperature value. Steel that is unprotected (e.g., if the fireproofing is dislodged) can reach the air temperature within the time period that the fires burned within the towers. Thus, yielding and buckling of the steel members (floor trusses, beams, and both core and exterior columns) with missing fireproofing were expected under the fire intensity and duration determined by NIST for the WTC towers.

16. Was the steel in the WTC towers certified by Underwriters Laboratories (UL) to 1,100 degrees Celsius (2,000 degrees Fahrenheit) as some have claimed?

UL did not certify any steel as suggested. In fact, in U.S. practice, steel is not certified at all; rather structural assemblies are tested for their fire resistance rating in accordance with a standard procedure such as ASTM E 119 (see NCSTAR 1-6B). That the steel was "certified ... to 2000 degrees Fahrenheit for six hours" is simply not true.

17. NIST states that the fires in WTC 1 were generally ventilation limited. If this was the case, wouldn't the fires have burned out in about 2 minutes? Why do NIST's models show the fires burning longer?

Nearly all fires are limited either by the burning rate of combustible fuel (fuel-limited fires) or by the availability of air (ventilation-limited fires). Many fires that are ventilation limited do continue to burn, with the burning rate determined by the chemistry of the combustion and the rate at which the oxygen arrives. This was generally the case for the WTC Tower fires. Of course, if the rate of air inflow were too slow (e.g., due to very few broken windows), the limited combustion would not have generated sufficient heat to continue pyrolyzing fuel, and the fire would have gone out. This was not the case on the fire floors in the WTC towers.
The FDS, used to reconstruct the fires in the WTC towers, included the burning characteristics of the building combustibles and the ventilation through the broken windows and the damaged building façade. The simulation showed that there were ample perforations in the building facade to maintain the ventilation-limited combustion until the fuel supply was depleted.

Your argument is what again?

[_Lemmie]

Lemmie,

I was addressing Markk's horseshoe example, maybe melt is incorrect for that I'm not sure? But from what NIST and the paper I posted state the temperatures were only 1000 C for 15 minutes and hovered at 500C otherwise. That isn't enough for the weakening.

mikwut

I’m sure Markk can address this better, so I’ll just quote the National fire protection handbook to start:

structural steel begins to soften around 425°C and loses about half of its strength at 650°C.4 This is why steel is stress relieved in this temperature range

http://www.nfpa.org/Home/index.asp

[_Lemmie]

I am not an engineer and I have never gotten into the deep weeds of the NIST report. But just for yuks, I spent about 15 minutes looking at it because I was intrigued by the notion that there wasn't enough energy from the collision to cause both the structural damage and strip the insulation off the structural elements.

The NIST reported the results of its experiments in terms of the amount of acceleration required to strip the insulation off the structural members. Think about what that means.

It mean the paper mikwut cites double counts the energy needed under the NIST analysis. The same energy that damaged the structural elements also accelerated them, stripping off the insulation.

Now, I very well could be wrong. But if I am, please show me where I'm wrong. But if i'm right, then all it took to find a serious flaw in the analysis was to look at the source materials with a stance of "what are they actually saying here."

Exactly. The chapter that asserts explosions had to be the cause relies on “eye-witness” statements of people there that day that they saw “molten metal.” Some people described it as “molten steel.” On the basis of this incredibly non-scientific assessment, the paper concludes there actually was “molten steel.”

Since there is no way to explain that what people described as “molten steel” actually was “molten steel,” given the available facts, they had to add a new idea. it was caused by thermite detonations.

Of course, the far more reasonable assessment, that people in a heightened state might describe something as looking like “molten steel” without it actually being “molten steel,” is dismissed out of hand.

[_Res Ipsa]

I am not an engineer and I have never gotten into the deep weeds of the NIST report. But just for yuks, I spent about 15 minutes looking at it because I was intrigued by the notion that there wasn't enough energy from the collision to cause both the structural damage and strip the insulation off the structural elements.

The NIST reported the results of its experiments in terms of the amount of acceleration required to strip the insulation off the structural members. Think about what that means.

It mean the paper mikwut cites double counts the energy needed under the NIST analysis. The same energy that damaged the structural elements also accelerated them, stripping off the insulation.

Now, I very well could be wrong. But if I am, please show me where I'm wrong. But if i'm right, then all it took to find a serious flaw in the analysis was to look at the source materials with a stance of "what are they actually saying here."

Exactly. The chapter that asserts explosions had to be the cause relies on “eye-witness” statements of people there that day that they saw “molten metal.” Some people described it as “molten steel.” On the basis of this incredibly non-scientific assessment, the paper concludes there actually was “molten steel.”

Since there is no way to explain that what people described as “molten steel” actually was “molten steel,” given the available facts, they had to add a new idea. it was caused by thermite detonations.

Of course, the far more reasonable assessment, that people in a heightened state might describe something as looking like “molten steel” without it actually being “molten steel,” is dismissed out of hand.

Yeah, I agree with you on the whole molten steel thing. That's why eyewitness testimony, photographs, and videos have to carefully scrutinized. "Looks like molten steel" is not good evidence of molten steel.

This is a separate argument that I hadn't heard before: that, using the analysis in the NIST report, the crash simply didn't have enough energy to do the structural damage and the insulation removal that were both necessary causes of the collapse. The problem I see is that mikwut's paper treats those as two independent sources of energy, so you can add them together. But the damage to the structural components involves accelerating them. So mikwut's paper double counts the required energy.

[_Doctor CamNC4Me]

The aircraft impact no doubt destroyed several columns in the WTC perimeter wall; the # of columns lost on the initial impact according to the NIST report was not large and the loads were shifted to remaining columns in this highly redundant structure.

So what happened? Of equal or even greater import to the initial impact was the explosion of tens of thousands of gallons of jet fuel, comprising nearly 1/3 of the aircraft’s weight, ignited. The ensuing fire was clearly the principal cause of the collapse. How?

According to MIT each floor system weighed about 3,200,000 pounds. The jets destroyed support columns, weakened support columns, and fire burning at around 800 degrees for, what, 45 to 60 minutes? In one of the towers you had multiple jacked up floors trying to shift weight of +/- 96,000,000 lbs of weight bearing downward. Once all that debris and ash and detritus started accumulating, plus whatever else was burning and warping, the fact that the wtcs lasted as long as they did is a testament to their design.

A broken ankle ain’t gonna support your weight for long, man. You may stand for a bit, but you’re not faking it once you collapse. And no one needs to come along and cap you in the knee to finish you off, either.

- Doc

[_Chap]

Exactly. The chapter that asserts explosions had to be the cause relies on “eye-witness” statements of people there that day that they saw “molten metal.” Some people described it as “molten steel.” On the basis of this incredibly non-scientific assessment, the paper concludes there actually was “molten steel.”

Since there is no way to explain that what people described as “molten steel” actually was “molten steel,” given the available facts, they had to add a new idea. it was caused by thermite detonations.

Of course, the far more reasonable assessment, that people in a heightened state might describe something as looking like “molten steel” without it actually being “molten steel,” is dismissed out of hand.

If people who have seen from ground level what is later verified to have been real molten steel running from a burning building say on a subsequent occasion that they have seen molten steel running from a different burning building, then their testimony about the second building has some weight.

If one the other hand they are simply looking at a burning building from the ground, and exclaim 'look, there is some molten steel', then I have to say that their exclamation does not in itself have much evidential value. It just shows they have seen very hot burning stuff, are excited and imaginative, and are aware that steel plays a major part in tall building construction.

[Guest]

It’s not like steel was the only metal in the wtcs. Aluminum, copper, I dunno, what else? Tin foil for all the hats we’re seeing in this thread?

- Doc

[_Maksutov]

There are some interesting hot button events and subjects.

9/11 is one. The Waco apocalypse is another. Elian Gonzales. Alien abductions. People go from cool to homicidal at the drop of a effing hat.

[_Chap]

[...]

Your theory demands these, and other, questions answered.

1. what team engineered the controlled demolition. The pentagon? Private engineers? Did Bush just make a phone call to these men and say (using your best Bush impersonation)" Hey, I need a war, I want to blow up the Twin Towers and ram high jacked planes into the White House and the Pentagon. Get on it boys, but don't let anyone find out...if you have any further questions just ask Dick, by the way...see if you can find some dumb foriegn nationals that will fly the planes into the buildings."
2. who performed, and how, the preparation work involved for a sequenced implosion, with the airliners. And where were the charges placed?
3. who recruited the so called terrorists, and why would they give their lives for a goverment operation. Or...were they really terrorists tricked into the operation? If the latter who did this, who set it up?
4. controlled demolition would take 1000's of feet of sequencing wires, from charge to charge to a central command center and control board...where was that and where were the wires ran? Underground? In the subway? overhead? If so was there a clean up crew removing all this evidence, and I have to ask..."who were these guys?"
5. How long did it take Bush, from inception to the end, plan and execute the operation?

We don't refute science by saying well if that science is true then we have to believe something too difficult to imagine. The science is first. If the collapse only could have happened one way then that's what happened.

mikwt

I think that as a lawyer (which is apparently what you are) you are not familiar enough with the application of science to the real world to be aware of the need to make an important distinction between:

(a) Basic and repeatedly tested scientific principles that most scientists would go to great lengths to avoid contradicting, such as the conservation of mass-energy, and the impossibility of travel faster than the speed of light. If (supposing an impossibility) it could be shown beyond doubt that the only way the collapse of the twin towers could be explained without violating one of those principles was a conspiracy theory involving all the fifth-graders of Manhattan cooperating on a really malevolent science project, then the result would certainly be a lot of scientists wondering if it was safe to go near a grade school again.

(b) Attempts to apply basic scientific principles to hugely complex and rare (even unprecedented) events such as the collision with a tall steel structure of an airplane travelling with a heavy fuel load. The great majority of scientists faced with such situations are modest enough to admit that even if there are complexities about being sure exactly what the collapse mechanisms were, that does not indicate that it makes sense to default to a conspiracy theory, with its undoubted burden of high implausibility. Science that is simple in the lab is rarely so simple once you are out of it: there are just too many unknown factors. And people who have done science tend to know that.