Goodbye, Mr Roberts

[Ghent12]

Re: Goodbye, Mr Roberts

That was not my assumption in the general case. In this particular case (WTC2) we need more heat than we have, given the load applied.

I think you're making a fatal assumption. I believe that you are assuming scale does not matter, and that any given steel structure can be expanded to enormous sizes without any adverse effects. You say, "given the load applied," but I don't think you understand the effect of the applied load. It is very likely more than any building that has ever caught fire. The WTC towers had roughly 39,000 square feet of space per floor which is roughly twice the area (and although not necessarily a linear relationship, that nevertheless translates into substantially more weight) of the buildings mentioned by the 911research site that I can find data on (which had between 17,000 and 21,000 square feet per floor). Couldn't find info on the TVCC building (aka Beijing Mandarin Oriental Hotel), except that it was built to withstand earthquakes and built three years after 9/11.

So when you say "given the load applied," I would ask that you keep in mind that this is a very, very large force.

Of course. Sufficient load will bend steel, and the right combination of load and heat, each insufficient by itself, can deform or destroy the structural integrity of a piece of steel.

Where was the tremendous load, above and beyond (1) the initial plane impact, which did indeed destroy some of the steel, and (2) the long standing static load which was always there and easily supported both before and after the plane impact? Look at the videos. The upper buildings of WTC1 & 2 are not dropped anywhere. They start crumbling exploding from the bottom up, allowing the upper portion to sink into the lower building. The only way that the upper buildings could have been dropped (as would be necessary to create a tremendous impulse, above and beyond the everyday static load) would be if some floor or two in the impact zone failed massively and suddenly, across the building span. Indeed, that's exactly what happened. It took explosives, clearly visible on the videos and heard by those present, to accomplish that. The heat was no where close to causing sudden full span failure. If one side failed first, as happened in WTC2 and if this was due to heat stress alone, then the other side would have not received any sudden tremendous increase in load that might account for its massively failing a second or two later.

You have a very, very different interpretation of the videos. Further, all this talk of offset or one-side-first impacts doesn't address lateral forces, of which the building would have to be designed to withstand wind forces and little else.

Also, please bear in mind that we're talking about one object falling onto another, so all this sarcasm of yours' relating to tremendous impulse seems to neglect that you then expect a structure, having just failed to hold up the weight of something above, would simultaneously withstand the impact of the largest dropping weight in history and withstand its static load. This is truly your expectation?

I tried quite carefully to ask the question in the previous paragraph earlier in this thread, and all I got in repy was "For all your examination of trees, you seem to have no concept of the forest."



Of course, sufficient heat can destroy steel. What matters is how much heat versus how much steel. In other steel frame building fires, it took substantially longer lasting fires to provide even a modest partial collapse of substantially lighter (thinner and less total mass) steel frames.

Whereas no people were able to survive in the raging infernos that took down six of the top stories in Madrid after 8 or 10 (I forget exactly) hours, and whereas no people were able to survive in the similar fire that took down one side of one lightly constructed wing of the architecture building in Delft again after some 8 to 10 hours (with perhaps, I can't tell, only the portion of the building above the fire collapsing at that time), and whereas WTC1, which had a more direct hit presumably taking out more core columns and leaving more jet fuel to burn within the building took nearly two hours for its collapse (which itself I for one don't think came down just due to that fire even then), still in the case of WTC2 after only 56 minutes of a cooler (less jet fuel) fire on a building with less core damage than WTC1 and with people alive above, just below and even standing visibly in the broken exterior wall where the plane hit (all indications of temperatures below 100 or 120 degrees F), the building suffered a sudden catastrophic total collapse.

I observe substantial less heat, shorter time, less preliminary physical damage, but still total collapse rather than (as in the case of all other steel frame fires I know of save the WTC on 9/11) no or at most rather limited collapse.

Then study, please, the Herbst survey that I linked above. The list of evidence that contradicts the official story and must therefore be ignored or discredited by less than honest means is stunning in its variety and length.

One of the problems I face by focusing this 9/11 discussion on the physics of the WTC building failures is that some will think that since the rest of the official story presumably holds, being unchallenged here, therefore the offical story for the physics of the WTC building failures deserves the benefit of their doubts.

The whole bloody thing is a massive con job. Wake up!

Sigh...
The thing is, all of these sources are convinced it was an inside job, just as you. All of this "evidence" they present must be discredited because it is not credible to begin with. Do you think your group of teachers and secretaries or teaching assistants from second-rate colleges leading the A&E for 9/11 Truth group have had a favorable (and legitimate) peer review of their claims?

You're telling me to wake up, but you like all Truthers keep seeking evidence to prove your conspiracy theory, rather than letting the evidence speak for itself.

However, I will say you have made progress. Before, one of your key arguments was that the WTC must have been demolished because collapse from the damage from the impact and subsequent fires would be impossible. You have since stated that you can't say it's impossible (in response to c1ue saying that the nano-thermite theory isn't necessarily impossible), and that is commendable progress. As a next step, I think you should very carefully consider the "no skyscraper in history has collapsed from fire" evidence and look very closely at each individual case. See if they are truly comparable, and whether such a comparison is valid given all the factors.

[ThePythonicCow]

Re: Goodbye, Mr Roberts

I think you're making a fatal assumption. I believe that you are assuming scale does not matter, ...

So when you say "given the load applied," I would ask that you keep in mind that this is a very, very large force.

It's the local force that counts, the force per square inch of material.

You have a very, very different interpretation of the videos.

I've pointed you to a somewhat detailed analysis of the videos as I see them. Could you point me to a detailed analysis of the videos as you see them or provide such analysis yourself? By this I mean an analysis that considers the specifics of smoke and debris and building color, velocity, and acceleration, during the first second or two of collapse?

Or are your credentials so impeccable that I should just bow before your superior expertise and reputation?

Also, please bear in mind that we're talking about one object falling onto another, so all this sarcasm of yours' relating to tremendous impulse seems to neglect that you then expect a structure, having just failed to hold up the weight of something above, would simultaneously withstand the impact of the largest dropping weight in history and withstand its static load. This is truly your expectation?

It is not sarcasm.

It is sincere and concerted and repeated effort, so far without any success, to get you or c1ue or anyone to explain how the upper building drops onto the lower building with sufficient momentum (hence across a sufficient distance unimpeded) to produce a large enough impulse to cause total crushing of the hitherto undamaged lower building at near free fall speeds.

Obviously the lower building could hold the static weight (several times over according to the sources I referenced) and obviously the lower building was almost entirely undamaged prior to the collapse. The only way that the lower building could suddenly have been totally crushed would be if the upper building dropped onto it over some distance (a rather large distance I would suspect.) You repeatedly only answer my question with scorn, ridicule and incomprehension. As you said ... Sigh.

You're telling me to wake up, but you like all Truthers keep seeking evidence to prove your conspiracy theory, rather than letting the evidence speak for itself.

I keep presenting evidence, which you won't read or comprehend.

I keep hearing hypothetical theories (and less worthy rhetoric) from you that don't fit the facts.

As a next step, I think you should very carefully consider the "no skyscraper in history has collapsed from fire" evidence and look very closely at each individual case. See if they are truly comparable, and whether such a comparison is valid given all the factors.

Well, of course, there is no perfect comparison. You can say some collapse has occurred to which I can respond but there were differences one way (longer fires, less collapse, lighter structures) while I can say that collapse has not occurred in this particular way on this particular sort of structure and of course I'm right.

I cannot prove what happened based on the limited comparisons available and neither can you. The comparisons can help one understand some of the variables and help one understand the WTC case better. Well, I should say "could help" (subjunctive tense), as apparently in your case, the examples just provide more rhetorical fodder.

===

If there is anyone left reading this sub-thread (between Ghent12 and myself) who would like me to continue, please speak up. So far as I can tell, my further responses to Ghent12 are only providing him with an opportunity to exercise his mental defenses guarding his current view of the events of 9/11. That is not a good use of my time. If no one else asks me to continue this sub-thread, and if whatever Ghent12 responds with is consistent with his previous responses here, I hope I have the self-discipline to not continue this sub-thread.

[Ghent12]

Re: Goodbye, Mr Roberts

It's the local force that counts, the force per square inch of material.

All force always counts. The applied force was that of a 100,000 ton object falling onto a structure of identical construction. If you don't account for all forces and their effects, you have a less than ideal setup which will not yield the correct result. Barring bogus undergrad papers erroneously concluding the fall should have been arrested using an improper setup (by intention or by ignorance), physics seems to dictate a gravity plunge of that mass should be more than enough.

I've pointed you to a somewhat detailed analysis of the videos as I see them. Could you point me to a detailed analysis of the videos as you see them or provide such analysis yourself? By this I mean an analysis that considers the specifics of smoke and debris and building color, velocity, and acceleration, during the first second or two of collapse?

Or are your credentials so impeccable that I should just bow before your superior expertise and reputation?

All aspects of the video are plausible under far simpler scenarios than nano-thermite demolition. c1ue covered one of your videos pretty well.

It is sincere and concerted and repeated effort, so far without any success, to get you or c1ue or anyone to explain how the upper building drops onto the lower building with sufficient momentum (hence across a sufficient distance unimpeded) to produce a large enough impulse to cause total crushing of the hitherto undamaged lower building at near free fall speeds.

Obviously the lower building could hold the static weight (several times over according to the sources I referenced) and obviously the lower building was almost entirely undamaged prior to the collapse. The only way that the lower building could suddenly have been totally crushed would be if the upper building dropped onto it over some distance (a rather large distance I would suspect.) You repeatedly only answer my question with scorn, ridicule and incomprehension. As you said ... Sigh.

Okay, let's start over on this point from your perspective. Please address these two questions:
What momentum would be sufficient?
From what height would an unresisted fall be sufficient?
You continually claim that the fall was insufficient to cause the effects witnessed. Prove it.

I keep presenting evidence, which you won't read or comprehend.

I keep hearing hypothetical theories (and less worthy rhetoric) from you that don't fit the facts.

Analysis isn't evidence, per se. It's a perspective which makes certain assumptions and draws conclusions based on observations in the framework of those assumptions. For instance, in one of the videos you present, the presenter makes the assumption that only a full sever of all core columns could produce the drop in the height of the antenna, yet there are other, more plausible explanations as well.

Well, of course, there is no perfect comparison. You can say some collapse has occurred to which I can respond but there were differences one way (longer fires, less collapse, lighter structures) while I can say that collapse has not occurred in this particular way on this particular sort of structure and of course I'm right.

I cannot prove what happened based on the limited comparisons available and neither can you. The comparisons can help one understand some of the variables and help one understand the WTC case better. Well, I should say "could help" (subjunctive tense), as apparently in your case, the examples just provide more rhetorical fodder.

The examples do indeed prove to be rhetorical fodder. Examination of the forces involved leads to the conclusion that although outward appearance may make the fires themselves appear even worse, there's far from many examples of planes hitting buildings, nor of fires affecting buildings previously severely damaged. Additionally, from what I have seen from the 911research site you claim I didn't look at but obviously did, it appears that all the buildings used for comparison had several factors that place them in wholly different categories apart from the lack of severe structural damage prior to the fire. Among them are apparent weight per story, total weight above area of fire concentration, and different structural design.

If there is anyone left reading this sub-thread (between Ghent12 and myself) who would like me to continue, please speak up. So far as I can tell, my further responses to Ghent12 are only providing him with an opportunity to exercise his mental defenses guarding his current view of the events of 9/11. That is not a good use of my time. If no one else asks me to continue this sub-thread, and if whatever Ghent12 responds with is consistent with his previous responses here, I hope I have the self-discipline to not continue this sub-thread.

Suite yourself. I am assaulting your superstition, after all.

[ThePythonicCow]

Re: Goodbye, Mr Roberts

Okay, let's start over on this point from your perspective. Please address these two questions:
What momentum would be sufficient?
From what height would an unresisted fall be sufficient?
You continually claim that the fall was insufficient to cause the effects witnessed. Prove it.

No, that's not what I'm saying. I am not saying the fall was insufficient. I am not saying that some upper portion fell across some insufficient height onto some lower portion, insufficient to cause further collapse.

I am saying you have no way to get started the initial floor wide collapse of any height (not 1 mm, not 1 ft, not 10 floors).

If you observe all the videos, the collapse of each tower started across the entire cross section of the tower simultaneously. Indeed, it is rather essential to the official story that each entire cross section fails at once, because we then have each subsequent floor also failing all at once, which means (if they each failed due to something falling on them) that whatever fell on them came down on them all at once.

In other building failures (not WTC), some one or perhaps a couple of adjacent joints or beams or supports give way first, and then the failure spreads out from there.

In the videos and in the official scenarios of the two WTC tower failures, each entire floor fails at once, starting from the very first failures visible in the videos. All failures are floor wide.

You have no explanation for how that initial failure occurred, across the entire cross section of the building. One instant before that mystical gap forms, the building is standing. One instant later, the upper portion is coming down, falling across some mystical gap created simultaneously across the entire building, onto the still standing lower portion.

How did that mystical gap occur?

My explanation is explosives. What's yours?

P.S. -- I'm agreeing with the words of c1ue in Post #85 above, when he stated that a "simultaneous [failure] at multiple levels/areas [would be] a truly unlikely scenario." A simultaneous failure across the entire cross section area of the building would indeed be a truly unlikely scenario. Hence my term the "mystical gap".

[Serge_Tomiko]

Re: Goodbye, Mr Roberts

If cui bono is your standard of evidence or proof of something, then your role in this conversation is probably finished. As I said, it may be usable as establishing a motive, but it has no relevance in the function of proof of action.

I missed this before. Clearly, cui bono is not "proof". Unfortunately, proving anything in the real world is easier said than done. The primary difference between a leader who makes history and a fool whose head remains in the clouds is decisiveness based on information that is available at a given time.

We do not have the time to spend a century analyzing every conceivable detail regarding tragic events. We can however look at the sum result of a variety of tragedies such as 9/11 and conclude that they seem to benefit those who wish exploit us far more than the partisans bent on our destruction.

Your response reminds me the retorts against banking cabals in the years leading up to World War II, or the efforts of the John Birch Society to warn the world about the new flavor of internationalism bent on destroying the West. The details and proof presented at the time doesn't really matter - their stories, their myths have in hindsight displayed much greater power and veracity than anything a myopic scientist could ever produce.

In short, I don't need evidence. Evidence is for Pharisees and anti-social scientists who would rather have their face planted in our millions of pages of legal text or a microscope. It is stories about glory, virtue, and the good life that inspire a sufficient minority to fight to create a better a world, a world that exalts the best qualities of human nature and existence, suppresses corruption and exploitation, and fights nihilism.

[Ghent12]

Re: Goodbye, Mr Roberts

No, that's not what I'm saying. I am not saying the fall was insufficient. I am not saying that some upper portion fell across some insufficient height onto some lower portion, insufficient to cause further collapse.

I am saying you have no way to get started the initial floor wide collapse of any height (not 1 mm, not 1 ft, not 10 floors).

If you observe all the videos, the collapse of each tower started across the entire cross section of the tower simultaneously. Indeed, it is rather essential to the official story that each entire cross section fails at once, because we then have each subsequent floor also failing all at once, which means (if they each failed due to something falling on them) that whatever fell on them came down on them all at once.

In other building failures (not WTC), some one or perhaps a couple of adjacent joints or beams or supports give way first, and then the failure spreads out from there.

In the videos and in the official scenarios of the two WTC tower failures, each entire floor fails at once, starting from the very first failures visible in the videos. All failures are floor wide.

You have no explanation for how that initial failure occurred, across the entire cross section of the building. One instant before that mystical gap forms, the building is standing. One instant later, the upper portion is coming down, falling across some mystical gap created simultaneously across the entire building, onto the still standing lower portion.

How did that mystical gap occur?

My explanation is explosives. What's yours?

P.S. -- I'm agreeing with the words of c1ue in Post #85 above, when he stated that a "simultaneous [failure] at multiple levels/areas [would be] a truly unlikely scenario." A simultaneous failure across the entire cross section area of the building would indeed be a truly unlikely scenario. Hence my term the "mystical gap".

Alright, you are having trouble conceiving of the physical reality of what happened. That's far different from proof of explosive demolition.

Here are a series of rhetorical questions to guide you to understanding how the process likely took place during what you call the mystical gap using readily available knowledge of the principles involved. They are based on the assumption that the heat in combination with the tremendous static load caused recrystallization which annealed the steel after it already suffered severe damage from the plane impact to the point of lowering its strength (see annealing above) such that it failed to support the entire weight of the static load of the upper section.

1) What happens at the exact instant motion begins to occur? What are the states of the steel where motion is allowed to begin first?
The first is a trick question. Motion almost always occurs in a microscopic way even at room temperature, and this is called creep. The motion that led to collapse was very likely a two-phase process. First, the steel acted in a manner similar to what you might think a cheap plastic plate would act if an iron were placed on top (and secured from sliding laterally more or less, and where the temperature was insufficient to melt it). The tremendous compression force began to deform the steel causing the first part of the 'real' motion. This is basically accelerated creeping.

This motion, assuming the fire and static load pressure were hot working the steel (which is physically what occurs to steel under high pressure at significant fractions of its melting point, so it is a valid assumption), actually very likely begins in an imperceptible way from the videos. The steel at such temperature has experienced thermal expansion, but its loss in strength and hardness is matched by an increase in toughness. This means it can undergo further strain (compression in this case) before fracture, therefore as the strength is reduced via grain growth of the steel, the weakest in terms of strength (i.e. softest, and therefore the most tough) parts of the steel began to give in to greater creep motion, eventually buckling.

2) What was the section phase of motion alluded to previously?
That would be the continuation of creep motion until a critical point, which is 'the collapse' seen in the videos. Think logically from about what happened at the critical points where creep motion was occurring. These areas of steel, perhaps larger than a story where creep motion occurred most, were not getting any stronger. The pressure was constant and the fire was still there. The creep motion continued to accelerate, leading to the buckling of the core columns, already damaged by the plane impacts. Once buckling occurred in earnest, the cascade of failure was very rapid; now the damaged-but-still-holding columns and the virtually undamaged columns alike were tasked with supporting the entire static load. Those already subjected to accelerated creep motion or minor buckling were very quickly forced into extreme buckling and fracture, and those virtually undamaged columns were then almost instantaneously tasked with supporting the entire static load. As the central columns buckled very rapidly, they pulled inward on the floor and the remaining columns were overwhelmed by the now-dynamic load.

3. But how could it have happened so fast as to appear as an instantaneous, whole-floor failure?
Primarily because by the time the motion was perceptible to the distant cameras viewing it, the core columns were buckling in earnest and dragging the rest of the damaged and intact columns down with them. The whole thing cascaded rapidly because the remaining areas with compressive strength remaining were being overwhelmed at the same time the buckling which had begun at the area of most damage was not about to offer much in the way of compressive strength. In short, resistance to falling suffered a precipitous decline. There was remaining resistance in the areas of least damage, hence the tilting we've gone over, but those columns were very likely in the process of buckling from the new lateral loads and the ever-increasing dynamic load as the collision between floors on the far side wiped out the support for that far side.

4. But why has no other steel structure suffered a similar collapse?
This has been addressed before. In short, none have suffered a similar casualty. None suffered immediate onset of multi-story and whole-story fires, none have suffered from a comparable impact force, etc.

----------

All of this is consistent with metallurgy as I understand it, physics as I understand it, and thermodynamics as I understand it. Further, it at least appears that basically all of this is consistent with innumerable people with greater understanding of those subjects than I.

Summary:
Fire softens steel and static loads apply constant compressive pressure. Hence, the tower with substantially more static load above the damaged section had an onset of global collapse far sooner than the one with less static load. Furthermore, the manner of each towers fall is consistent with the region of most damage from plane impact and fire concentration.

It is completely plausible, and is absolutely the most likely scenario by far.

[c1ue]

Re: Goodbye, Mr Roberts

The impact area on the South Tower extended from floor 78 to floor 94.

P.S. -- The primary impact area on the South Tower was floors 78 to 82.

OK, let's focus on the WTC South Tower.

Your assertion is that there wasn't much fire. But the actual NIST report says otherwise:

wtc.nist.gov/WTC_Conf_Sep13-15/session6/6McAllister.pdf

This report shows that WTC1 was clearly damaged by fire - there is not only visible deformation of the walls - they were bowing inward - but also visible evidence of fires on all 4 faces.

WTC2 in contrast had less bowing - 20 inches, 12 inches, etc vs. the maximum of 55 inches. But there is clearly damage - a handing floor slab is shown in one photograph.

There is less visible fire damage, but it is still there on 3 of 4 faces (as opposed to all 4 faces of WTC1.

In fact there was even additional inward bowing right before WTC2 collapsed - as opposed to explosives blowing parts outward.

In addition, both WTC1 and WTC2 had visible tilt in the beginning of the collapse - NOT a straight fall down as is alleged via demolition.

McAllister 18.bmp

Secondly, the analysis of the aircraft impact entry point indicates significant damage to the core columns: 10 severed and 13 with various stages of damage out of a total of 47 or so.

McAllister 21.bmp

The report goes on to talk about other forms of structural damage, fire protection damage, and even a significant vibration in the entire building due to the impact.

Again, I don't see anything unusual - it is likely that any one of the above forms of damage would have been sustainable by the WTC buildings without collapse, but the combination of all of the above was not.

To summarize:

The presupposition that the WTC 1 and WTC 2 buildings could not have collapsed on their own is directly in contradiction to the NIST reports.

The NIST documents both extensive evidence of structural damage (inward bowing) and cascade collapse (tilting of upper floors). Extensive fire damage is also documented as well as specific examples of visible structural damage.

[ThePythonicCow]

Re: Goodbye, Mr Roberts

• There was no fire visible outside WTC2 when it collapsed and only modest fire visible before then, other than the initial fireballs outside the building at the time of impact.
• There was little smoke coming from WTC2 when it collapsed, indicating little fire inside.
• What little smoke that was coming from WTC2 by then was quite dark, indicating a cool fire.
• There were firemen up to floor 78, the bottom floor of the impact zone, inside the core, indicating rather mundane temperatures in the core at that level.
• The plane that hit WTC2 hit at an angle off-center, resulting in less damage to the core columns.
• People above the impact zone were able to walk down the stairwell in the core through the impact zone in WTC2 (unlike in WTC1.)
• Three of the supporting columns in the exterior corners were undamaged by the impact and untouched by any sustained fire.
• All or most of the core columns were undamaged, not being in the direct line of the WTC2 impact. [P.S. NIST 2005 Report says 11 of the 47 core columns were severely damaged or severed.]
• The substantial majority of the exterior mid-wall (non-corner) columns (once again, enough to hold the tower by themselves) were undamaged and untouched by any sustained fire.
• The core columns, corner columns and mid-wall columns were each independently capable of supporting the weight of the building above them. The substantial majority of each were unharmed and unheated prior to the moment of the collapse.
• There was little of the usual flammable material in the core needed to sustain the typical "office" furnishings and interior construction materials fire.

In your scenario, what temperature did the steel have to get to and under what loadings, as say a percentage of the total force per area that the building design anticipated? It takes time to weaken steel by applying heat and force that are each at levels well below the point of rapid failure. Other steel buildings have taken 8 or 10 hours of raging fires to obtain even partial collapse; even WTC1 took a couple of hours (and that I claim also required explosives.) WTC2 fell in just 56 minutes. By a wide margin, your scenario lacks enough time, temperature and excessive (above design maximum loadings) force to initiate collapse. By a total margin, it lacks any means to sustain that collapse all the way to the ground, in the manner those towers collapsed on that day.

Your scenario requires that a sufficient number of the columns already be weakened somehow prior to collapse initiation that the remaining undamaged columns cannot hold the building. If enough undamaged columns are present, then no failure, gradual or sudden, of some columns will cause collapse, for no load bearing capacity whatsoever of the damaged columns is required to maintain structure integrity. How many columns (corner, core and mid-wall) do you claim were somewhat or somehow weakened prior to collapse initiation?

You present a scenario that might explain a partial failure, asymmetric and above the impact zone, given hotter fires, longer fires, on a building with less mass of steel and less over design of structure or with more critical structure substantially damaged on initial impact. Nothing you've said even begins to explain the floor wide uniform collapse of each floor below the impact zone, crushing two of the most massive structures on the planet at near free fall speeds into fine dust.

Why do you continue to dismiss, deny or ignore

• the demonstrated presence of thermetic material,
• the reports (heard, seen and on video) of loud explosions,
• the eye-witness reports and video evidence from many angles of explosive charges all the way down the building in the co-ordinated manner of a top-down controlled demolition,
• the repeated suppression of wide amounts of evidence including the material debris and eye witness reports,
• the inability of even the 9/11 Commission report to describe the physical nature of the tower collapse past the "point of initiation",
• the inability of the 9/11 Commission report to even consider WTC7,
• the clear suppression (publicly noted and objected to by multiple of the commissioners whose names are on the 9/11 Commission report) of the true story of the failed DOD interceptor response to multiple hijacked planes in the air for over an hour, ...

Have you read, carefully, the Herbst survey I referenced above? I have only touched on the long list of evidence, provided in that survey, that you ignore.

[ThePythonicCow]

Re: Goodbye, Mr Roberts

Note that the NIST table of how many core columns were damaged that you (c1ue) posted in #157 does not show the count of undamaged core columns. There were 47 core columns in total, so half or so were undamaged by their count. (Just how they arrived at these counts is not clear to me yet, but that's a separate issue I'm still considering.)

[ThePythonicCow]

Re: Goodbye, Mr Roberts

Your assertion is that there wasn't much fire. But the actual NIST report says otherwise:

I said no fire was externally visible in WTC2 when collapse started. The NIST photos on page 16 of the report you referenced shows one localized fire externally visible just before collapse. I was wrong in my assertion, though not by a great margin. I believe that my other assertions (reducing fire, reducing smoke, blacker hence cooler smoke) match what I see in the WTC2 images in that NIST report.

[Ghent12]

Re: Goodbye, Mr Roberts

I will post some quick replies before going to bed. You may receive more later.

Why do you continue to dismiss, deny or ignore

• the demonstrated presence of thermetic material,
• the reports (heard, seen and on video) of loud explosions,
• the eye-witness reports and video evidence from many angles of explosive charges all the way down the building in the co-ordinated manner of a top-down controlled demolition,
• the repeated suppression of wide amounts of evidence including the material debris and eye witness reports,
• the inability of even the 9/11 Commission report to describe the physical nature of the tower collapse past the "point of initiation",
• the inability of the 9/11 Commission report to even consider WTC7,
• the clear suppression (publicly noted and objected to by multiple of the commissioners whose names are on the 9/11 Commission report) of the true story of the failed DOD interceptor response to multiple hijacked planes in the air for over an hour, ...

You ask why I ignore those points, but they've all either been covered before or aren't relevant whatsoever.

• There was demonstrated presence of iron spheres and aluminum chips; four samples. See c1ue's post regarding high-energy environments.
• Loud explosions, almost as if a giant building was collapsing. Previously addressed.
• Video evidence and eye-witness accounts of air explosively escaping as the building collapsed, exactly 100% what you would expect from a collapse as explained in the official story. Again, previously addressed.
• If that evidence is suppressed, how do you know it exists or what it is? Additionally, the point you make is largely a comment on the manner of the investigation and salvage, not one which proves or disproves any theory about anything.
• The 9/11 commission was not really an engineering investigation, but more of a policy and interagency one. It was a politically appointed commission with a somewhat narrow mission to make agency structure organization recommendations, but limited in scope as to laying specific blame on individuals.
• Again, not really an engineering investigation, but a political one.
• Indeed, agencies did obstruct the investigation on the nature of their incompetence on 9/11. This proves what, exactly, other than that these agencies likely did not want to be revealed as incompetent?

All of your first bullet points relating to the fire are merely your own inaccurate perceptions of what transpired. Documented analysis and evidence indicate that the fire reached very substantial fractions of the melting point of steel. Your comment about corner columns able to support the weight is looking past the events that transpired as the core columns succumbed to eventual buckling, namely the laterally inward draw like a black hole sucking in the floor. The dynamic nature of it very likely induced buckling early, and the failure of just one corner in concert with the failed core column or columns would cause a bending moment on the rest, further exacerbating the lateral dynamic load applied by the moving of the steel composite floor.

Furthermore, other multi-hour fires were against heat treated steel. WTC steel was heat treated as well, at least until the impact of the plane.

[ThePythonicCow]

Re: Goodbye, Mr Roberts

The Gordon Ross I've referenced above has a nice (short and irreverent) rip of the NIST report at Reply to NIST. It makes some good (in my view) points that you will find it easier to read there than to have me repost here. Have a read.

However in findiing that, I rediscovered a paper I recall reading earlier. This time around, this paper makes more sense to me. It is Destruction of the World Trade Center North (pdf) by David Chandler (Journal of 9/11 Studies - Feb 2010).

It makes in my view a devastating analysis of the "pile driver" theory.

Please read Chandler's paper.

I'll introduce it here by way of whetting your appetite.

One major inadequacy of the analysis that we (c1ue, Ghent12 and myself) have been attempting here is shared by the FEMA report, the 9/11 Commission report, and the NIST report. Their detailed technical analysis pretty much ends with "and then general collapse begins." Skyson has tried valiantly to extend our analysis past this point, but he has not succeeded (for whatever reason) in communicating his insights to the rest of us.

The common understanding of these reports and of c1ue and Ghent12 here is that once general collapse begins, it is quite plausible (perhaps even likely) that the enormous weight of the falling upper portion will crush the lower portion. This is the so-called "pile driver" theory as in the NIST report, which replaced the "pancake" theory of the FEMA report because the pancake theory could not explain the collapse of the central core (with its 47 large vertical steel columns.)

This is based on the intuition that a falling mass pushes on you harder than a static mass. That intuition is true if you resist the falling mass, if you "get in its way and slow it down (F = ma, so by "slow it down" I more precisely mean "reduce it's acceleration")

However one of the videos allows for some quite detailed analysis of the downward velocity and acceleration of the upper portion of WTC1.

The upper portion did not decelerate as it impacted the lower portion. It accelerated all the way down at very close to -6.31 m/sec² (earth gravity at sea level is about -9.80 m/sec², by way of comparison.)

Therefore the upper portion was exerting less force than its normal static load applied to the lower portion throughout the general collapse. If the upper portion exerts less force than normal, not more, on the lower (heretofore undamaged) portion, then that does not account for the crushing of the lower portion.

The pile driver theory has received a crushing blow .

[ThePythonicCow]

Documented analysis and evidence indicate that the fire reached very substantial fractions of the melting point of steel.

Actually this is quite true.

The source of heat (fire or whatever) did not just reach substantial fractions of the melting point of steel, but exceeded the melting point, resulting in pools of molten steel in the rubble.

We've all burnt gasoline and kerosene (much like jet fuel) in steel and iron stoves. Often we do so with better air-gas ratios allowing for hotter and more efficient burning than an office fire. It's been a while since my kitchen stove or my cooking pot melted ;).

How did that molten steel get there? Something was there hotter than a carbon fueled fire.

P.S. -- There are also pictures of molten steel pouring out of the towers just before collapse, and spheroids of iron found in the debris. To make iron spheroids you have to melt the iron which takes a higher temperature than the finest jet fuel or office material fire can generate.

P.P.S. -- Those were iron spheroids, not steel. This material did not come from the steel in the building. Something formed small, hot, melted globs of iron and ejected it into the air so that it could form round liquid balls and solidify while still in the air. One possible source of small molten iron globs is thermite explosions. I've seen no other possible source suggested in my readings so far.

[ThePythonicCow]

Re: Goodbye, Mr Roberts

The afore mentioned David Chandler is good. I am reading his website now, at http://911speakout.org/, starting with the first paper he lists there Why I Am Convinced 9/11 Was an Inside Job . He also has a video collection at http://www.youtube.com/user/DavidChandler911. His lead video is called North Tower Exploding. It is an easy view and compelling.

You guys, c1ue and Ghent12, provide worthy discussion. But my certainty is reinforced by Chandler's work. It's showing and explaining what happened. They done blowed it up, real good.

Please consider Chandler's work.

[ThePythonicCow]

Re: Goodbye, Mr Roberts

Whereas WTC1 fell with a downward acceleration of about 2/3's of gravity, WTC7 fell with a downward acceleration of almost exactly gravity. This means that something had to remove the bottom of the building faster than the falling portion could fall into it, or else there would have been material impeding (reducing downward acceleration) the fall of the building.

See Chandler's three videos on this starting at WTC7: NIST Finally Admits Freefall (Part I) . This is more very damning evidence of what happened and of NIST's fraudulent efforts to cover it up.