WTC7 Revisited

[deep]

How much is ZERO? Can you read?

In this context, "zero" would mean free-fall speed, which is the speed at which the building collapsed. Like I said, I was was initially adapting to your methodology for timing the collapse - I don't agree with it, because the rest of the building was obviously still being supported at that time.

 

[Dave Rogers]

Unevaluated inequality fallacy? Sorry, but I'm not going to waste my time refuting imaginary fallacies, especially when you consider the numerous circumstantial generalization fallacies present in your explanation.

If you want to identify those fallacies and describe how they work in detail, please feel free to do so. Otherwise, you're at best just committing a tu quoque fallacy.

You've obviously overlooked the fact that it was Gregory who originally made the comment about zero resistance. Don't allow little details like that to get in the way of condemning me, though. April fools?

You've obviously overlooked the fact that Gregory presented his results as tentative and open to discussion, rather than immediately claiming that anyone who disagrees with him is dishonest. You've also obviously overlooked the fact that, when Ryan Mackey pointed out some shortcomings in his analysis, Gregory acknowledged them with thanks and added the comment that on further reflection he may have to revise his estimates of air resistance downwards, implying that the structural resistance now appears to be non-zero. But that would get in the way of assuming that anyone who disagrees with your snap judgements must be lying.

Dave

 

[DGM]

In this context, "zero" would mean free-fall speed, which is the speed at which the building collapsed. Like I said, I was was initially adapting to your methodology for timing the collapse - I don't agree with it, because the rest of the building was obviously still being supported at that time.

Did you actually read what Gregory and I were talking about before you jumped it? His calculations proving zero resistance. Did you happen to notice were he says he's got to revise his calculations? Do you think they're still going to show zero resistance? I don't.

BTW WHERE DID THE PENTHOUSE GO?

 

[Dave Rogers]

Getting back to the OP here: Gregory, while I think your aims are laudable, I think they're also unachievable. Here's why.

Let's take a slightly different approach, and look at the rate at which air has to be expelled from between two floors in order for complete collapse. For generality, consider firstly a pair of floor slabs, initially separated by height z, with area A and perimeter length S. In a time interval dt, the upper slab falls through a distance dz, giving an instantaneous velocity of dz/dt in the direction of negative z. An element dV of volume of air is expelled through an area Sz(t), and we can calculate that dV=Adz. The velocity at which the air is expelled is therefore Adz/Sz(t)dt = A/Sz(t) times the rate of fall of the upper block. All the values in this expression are positive except for z(t), which goes to zero at the moment of impact of the two slabs; at the point of impact, in this simple model, the air is expelled with infinite velocity, and the energy loss is therefore infinite.

Clearly this approach is physically unrealistic. However, the only way to recover a finite velocity is to retain a finite aperture for the air to be expelled through. This requires that either (a) some further disruption of the structure allows air to be expelled elsewhere, or (b) the slabs do not come into contact. (b) is, again, physically unreasonable in this instance. So, in order to obtain physically reasonable behaviour, it is necessary to assume that the floor slabs are broken before impact. The precise energy loss, therefore, becomes entirely dependent on the assumptions made about how much damage a floor slab suffers before striking the ground, and this is an area where we have no information to work from.

Another point to consider is the effect of the east penthouse. I agree with your surmise that it could not have reached ground level in the ~6 seconds before the facade collapse, but it is certain that the remains of this structure would have reached ground level well in advance of the end point of the collapse. From this point on, any air resistance to collapse must have been drastically decreased, because even assuming the penthouse punched a perfectly regular hole in every floor slab - a wildly unrealistic assumption; some further collateral damage seems inevitable - by the time it reached the ground then something like one-third of the building area allowed unrestricted egress of air.

For these reasons, I think the air resistance of the structure is intractable to calculation. I'm not sure your approach can even give a reliable limit, in either direction; in particular, the assumption that the entire volume of air between two floor slabs must be expelled through the perimeter, seems thoroughly untenable, as it relies on the floor slabs being substantially undamaged until they strike the ground.

Moving on to a more tangential point, let's assume that your hypothesis in the OP were correct, and that the structural resistance to collapse was zero. This requires that at least the majority of columns were severed by other means prior to impact with the ground. While the core columns might be severed without the means being visible on videos of the collapse, this could not be the case for the perimeter columns. Your hypothesis therefore requires that either the perimeter columns were comprehensively structurally disrupted at the moment of collapse initiation by some means invisible to video, which rules out any possible explosive device, or that they were structurally disrupted by a series of sufficiently precisely timed explosive devices as they entered the collapse zone, requiring detonation timings with a precision significantly better than one-tenth of a second. I would go so far as to say the first possibility is simply ruled out by observation. What, then, would be the point of the second, when its only possible function would be to accelerate the collapse of a building already certain to collapse without its use?

While I appreciate that you feel you've discovered a possible anomaly, this anomaly (if valid) doesn't suggest a sane alternative hypothesis. A simpler explanation would be that your starting assumptions are oversimplified to the point of invalidity.

Dave

 

[LashL]

Derail. Any comments on the OT?

If you do not wish your comments to be questioned or discussed, you should refrain from making them. It wasn't me who introduced the photos, and it wasn't me who suggested that one of them must be bogus. Personally, I have seen no evidence that either of them is bogus. Moreover, this thread is ostensibly about your research, and you certainly didn't complain when the photos were introduced, so how is it a derail for me to ask you what you have done about authenticating or refuting them when you have questioned their authenticity in this very thread?

I can certainly understand why you do not wish to answer my straightforward inquiry (since the answer is obviously, "not a darned thing") but to call it a derail when it was, in fact, a direct response to your own words, well, I think thou really doth protest too much.



(Apologies to Dave Rogers and jaydeehess and others for posting this in the midst of your informative posts but I felt the need to respond to GregoryUrich's lame post in response to mine, sorry. Now, back to your regularly scheduled debunking. )

 

[Slayhamlet]

LOL, you're on a roll.. I said "near free-fall speed" because I don't feel like getting into an argument over how to measure the speed of a building collapse. Yes, there was obviously resistance present when the penthouse first started to fall (while the rest of the building was clearly still being supported), but after that it came down at free-fall speed.

And you've still provided zero evidence of this claim. People (such as Gregory) with greater curiosity and far less blind devotion to a political agenda than yourself have actually attempted some calculations to prove it one way or the other.

So yeah, nice job "making me look even more the fool" (sic). Try to form a coherent sentence next time you feel the urge to insult someone.

First, when you put quotation marks around words and append "[sic]" to it, the words are supposed to be an exact quotation. Second, the phrase DGM used is a common expression and not at all incoherent.

 

[R.Mackey]

You've also obviously overlooked the fact that, when Ryan Mackey pointed out some shortcomings in his analysis, Gregory acknowledged them with thanks and added the comment that on further reflection he may have to revise his estimates of air resistance downwards, implying that the structural resistance now appears to be non-zero.

Even Gregory's original post doesn't claim resistance is zero, only that it's surprisingly small. My calculations verify that a small amount of structural resistance is actually expected. Gregory's numbers may not be far off.

The resistance is higher in the WTC 1 and 2 cases, again, because there we have not only structual resistance, but also momentum transfer. It is this momentum transfer that dominates the delay in collapse. In WTC 7, no momentum transfer occurs. That's because the plane of interaction is (roughly) at ground level.

Any argument to the contrary, i.e. "WTC 7 came down too fast," is simply ignorant. Common sense is wrong in this particular problem, and simple mathematics demonstrates this.

 

[GregoryUrich]

If you do not wish your comments to be questioned or discussed, you should refrain from making them. It wasn't me who introduced the photos, and it wasn't me who suggested that one of them must be bogus. Personally, I have seen no evidence that either of them is bogus. Moreover, this thread is ostensibly about your research, and you certainly didn't complain when the photos were introduced, so how is it a derail for me to ask you what you have done about authenticating or refuting them when you have questioned their authenticity in this very thread?

I can certainly understand why you do not wish to answer my straightforward inquiry (since the answer is obviously, "not a darned thing") but to call it a derail when it was, in fact, a direct response to your own words, well, I think thou really doth protest too much.



(Apologies to Dave Rogers and jaydeehess and others for posting this in the midst of your informative posts but I felt the need to respond to GregoryUrich's lame post in response to mine, sorry. Now, back to your regularly scheduled debunking. )

My bad. I should have called the derail earlier. My terse reply was in reaction to your insulting approach which attempts to characterize me as a do nothing whiner. I think I have demonstrated my commitment to doing evidence based research and your attack is completely unwarranted.

To answer your question, no I'm not going to pursue that issue. I don't have time to chase every issue which is why I suggested that it was worth pursuing. I am quite busy with a fairly large paper in the works debunking Ross, Kuttler (WTC1) and to some extent Bazant. My preliminary result is that while Bazant and Zhou made egregious omissions, their overall conclusion that collapse would progress (in WTC1) is correct.

 

[jaydeehess]

Thanks- your comment literally made me laugh out loud..

I'm guessing that the near free-fall speed of the collapse isn't enough to convince you, so how should one go about satisfactorily "showing" that the building collapsed without little or no resistance?

In other words, you're demanding "proof" for something that is obvious to any objective-minded observer.

First of all there "free-fall speed " is a misnomer. Free fall acelleration or free fall time would be correct but not speed.

Secondly you do state that a condition of "no" resistance, ie. equalling zero, could describe what occured. However the only possible way to obtain such would be to destroy every floor's columns, or a large percentage of them, all at the very same time. Since that is not observed as having happened then the condition of "no resistance did not occur.

So that leaves "little resistance" and "near at free fall rate/acelleration/time" which does require that one attempt a quantification of how much resistance there indeed was. GU is moving along those lines and thus obviously not inclined to accept 'common sense' arguements. Too bad more were not like that.

ETA: I see Dave already said much of what I just did

 

[beachnut]

My bad. I should have called the derail earlier. My terse reply was in reaction to your insulting approach which attempts to characterize me as a do nothing whiner. I think I have demonstrated my commitment to doing evidence based research and your attack is completely unwarranted.

To answer your question, no I'm not going to pursue that issue. I don't have time to chase every issue which is why I suggested that it was worth pursuing. I am quite busy with a fairly large paper in the works debunking Ross, Kuttler (WTC1) and to some extent Bazant. My preliminary result is that while Bazant and Zhou made egregious omissions, their overall conclusion that collapse would progress (in WTC1) is correct.

So is this thread the search for the ample evidence you said you already have to say this? (your B and Z conclusion was as I said; so will this be)

… ample evidence and probable cause to believe that many grave and still unresolved crimes were committed by US officials prior to, during and after the events of 9/11…

… not limited to abetment of mass murder, criminal negligence, insider trading, and obstruction of justice, …

Where does WTC7 fit and this thread in you preconceived world of 9/11 truth petition signing and your quest, albeit failed, for truth?

Are you trying to manufacture the evidence you need after you say you had it already? So which part of WTC7 failure fits into your preconceived conclusion? Or are you telling a fib you have "ample evidence"? How can you even waste time on this thread since you have "ample evidence"? Why does the WTC7 even figure in your truth quest and why are people unable to understand the physics of failure?

Seriously, I have studied your thread and it again is a story of you learning about things as you go and try to back in your "ample evidence". Did I miss where you are actually trying to expose the truth, or are you really trying to back in evidence even in this thread of the WTC7? Does this mean you have failed to support thermite and CD in the WTC towers failure, since you have started this thread?

Can you 9/11 truth people ever tell anyone what your real goal is? I mean you have the ample evidence, or do you? I find your OP weak on purpose, and your preconceived conclusion kind of anti-research and knowledge, on the very idea of WTC7 revisited. And still the big question is why is WTC7 important in 9/11 truth fantasy ideas?

Why is 9/11 truth unable to find support from a majority of engineers on topics of WTC7 and their fantasy of CD? I mean 0.00087 percent of all world engineers is not a majority, and there is no real evidence. How can you support 9/11 truth without real evidence to support their conclusions based on hearsay and made up ideas like thermite, and CD? At least you have Deep44 and Major Tom helping you find the "truth"; I wonder what Jones has to add? Ironic stuff.
So how is the WTC7 revisited coming? Oh, you already made up your mind, until you actually have the facts in, dispite the "ample evidence"??

 

[GregoryUrich]

So is this thread the search for the ample evidence you said you already have to say this? (your B and Z conclusion was as I said; so will this be)
Where does WTC7 fit and this thread in you preconceived world of 9/11 truth petition signing and your quest, albeit failed, for truth?

Are you trying to manufacture the evidence you need after you say you had it already? So which part of WTC7 failure fits into your preconceived conclusion? Or are you telling a fib you have "ample evidence"? How can you even waste time on this thread since you have "ample evidence"? Why does the WTC7 even figure in your truth quest and why are people unable to understand the physics of failure?

Seriously, I have studied your thread and it again is a story of you learning about things as you go and try to back in your "ample evidence". Did I miss where you are actually trying to expose the truth, or are you really trying to back in evidence even in this thread of the WTC7? Does this mean you have failed to support thermite and CD in the WTC towers failure, since you have started this thread?

Can you 9/11 truth people ever tell anyone what your real goal is? I mean you have the ample evidence, or do you? I find your OP weak on purpose, and your preconceived conclusion kind of anti-research and knowledge, on the very idea of WTC7 revisited. And still the big question is why is WTC7 important in 9/11 truth fantasy ideas?

Why is 9/11 truth unable to find support from a majority of engineers on topics of WTC7 and their fantasy of CD? I mean 0.00087 percent of all world engineers is not a majority, and there is no real evidence. How can you support 9/11 truth without real evidence to support their conclusions based on hearsay and made up ideas like thermite, and CD? At least you have Deep44 and Major Tom helping you find the "truth"; I wonder what Jones has to add? Ironic stuff.
So how is the WTC7 revisited coming? Oh, you already made up your mind, until you actually have the facts in, dispite the "ample evidence"??

Beachnut, before I put you back on ignore, I think it is only fair to respond to your continued personal attacks and misrepresentations.

I signed a petition supporting a group pursuing a new investigation. While I do not agree with everything they are saying, I do feel an investigation is warranted.

You, on the other hand, have been an active participant in the war crimes of Desert Storm contributing to the deaths of 1.5 million Iraqis. Do the so called "militants" hate us for "our freedom" OR DO THEY HATE US BECAUSE WE DESTROYED THEIR COUNTRY AND KILLED THEIR LOVED ONES. There is no question in my mind why you are so hostile to any type of investigation which would examine the possible wrong doings of our government and military. I hope you and Norman "bombed them back to the stone-age" Schwarzkopf get what's coming to you.

 

[fullflavormenthol]

You, on the other hand, have been an active participant in the war crimes of Desert Storm contributing to the deaths of 1.5 million Iraqis. Do the so called "militants" hate us for "our freedom" OR DO THEY HATE US BECAUSE WE DESTROYED THEIR COUNTRY AND KILLED THEIR LOVED ONES. There is no question in my mind why you are so hostile to any type of investigation which would examine the possible wrong doings of our government and military. I hope you and Norman "bombed them back to the stone-age" Schwarzkopf get what's coming to you.

That is a very strong statement to make against someone, and it is a stupid accusation at that. If Desert Storm is a war crime than it would be one committed under the auspices of the U.N. Security Council and NATO.

What is implied to me by that statement is that you hate the military. I don't like the military either, but that is in a general "I don't believe in killing" sort of way. Your statement, though, is more along the line of hating everyone in the military personally.

That and I don't like the "I hope you and Norman "bombed them back to the stone-age" Schwarzkopf get what's coming to you." statement you made. So while I may be new here, I will report it the next time it happens. Because such a statement is the intellectual equivalent of telling someone to go to hell or **** off. It has no place in a forum debate. OR worse, implying that your opponent should have an act of violence visited upon them. The issue is that the phrase "whats voming to you" is a vague and can mean anything, and since you are refering to war crimes, the inference is that violence is that "what's" in the statement.

Accusing someone in a forum of a crime, without any evidence, is a personal attack; one that weakens your position.

 

[stateofgrace]

Beachnut, before I put you back on ignore, I think it is only fair to respond to your continued personal attacks and misrepresentations.

I signed a petition supporting a group pursuing a new investigation. While I do not agree with everything they are saying, I do feel an investigation is warranted.

You, on the other hand, have been an active participant in the war crimes of Desert Storm contributing to the deaths of 1.5 million Iraqis. Do the so called "militants" hate us for "our freedom" OR DO THEY HATE US BECAUSE WE DESTROYED THEIR COUNTRY AND KILLED THEIR LOVED ONES. There is no question in my mind why you are so hostile to any type of investigation which would examine the possible wrong doings of our government and military. I hope you and Norman "bombed them back to the stone-age" Schwarzkopf get what's coming to you.

Gregory.

I like many people, I am sure,simply like to lurk as threads like this one unfold. Even though I don't contribute to it, I am interested in what all parties have to say on this matter. I actually find it enlightening and at the same time educational. I see also as threads like this progress that people do post things they later regret.

What you have just posted has no place in this thread, it is beneath you and quite frankly appalling. I simply want to say, as somebody who as participated in anti war demonstrations that your opinions on this matter are not constructive. To actually accuse somebody of a war crime on a public forum is quite simply dreadful.Even though I am opposed to war in Iraq, your opinions and views are not reflective of mine or other people I know.

Please, I urge you to take a deep breath, calm down and retract your statements. Equally so I suggest you apologise for making such unfounded and awful accusations.If you will not, then I will do it for you and apologise on behave of myself and the many people I know who genuinely do oppose this war. I will apologies on behave of myself and others who do not feel the need to spit on the backs of the honourable service men and women who risk their lives everyday just so you can accuse them of war crimes.

 

[SDC]

GregoryUrich... you refer to "Norman 'bombed them back to the stone-age' Schwarzkopf.") I'm not aware that Schwarzkopf said that. I recall it as attributed to Curtis Lemay back in Vietnam war days. From your presentation you evidently believe that Schwarzkopf said it. Please source that.

Seriously. Thanks. Life is hard enough without falsely attributed quotations.

 

[pomeroo]

Beachnut, before I put you back on ignore, I think it is only fair to respond to your continued personal attacks and misrepresentations.

I signed a petition supporting a group pursuing a new investigation. While I do not agree with everything they are saying, I do feel an investigation is warranted.

You, on the other hand, have been an active participant in the war crimes of Desert Storm contributing to the deaths of 1.5 million Iraqis. Do the so called "militants" hate us for "our freedom" OR DO THEY HATE US BECAUSE WE DESTROYED THEIR COUNTRY AND KILLED THEIR LOVED ONES. There is no question in my mind why you are so hostile to any type of investigation which would examine the possible wrong doings of our government and military. I hope you and Norman "bombed them back to the stone-age" Schwarzkopf get what's coming to you.

Wow! You loony-leftists are up to 1.5 MILLION dead Iraqis now? If you double the absurd, thoroughly debunked estimate of 650,000, you're still a couple of hundred thousand short. In reality, the deaths of 40-70,000 Iraqis, the majority killed by other Iraqis, should not be minimized. But, please try to remember that Saddam is responsible for over a million dead Iraqis, Iranians, Kurds, and Kuwaitis, and you don't care.


* To be fair, a serious study places the death toll at 151,000, a higher figure than I am accustomed to seeing. Your nonsensical fabrication is wrong by a mere factor of ten, and not twenty or thirty.

http://www.washingtonpost.com/wp-dyn/content/article/2008/01/09/AR2008010902793_2.html

 

[rwguinn]

Beachnut, before I put you back on ignore, I think it is only fair to respond to your continued personal attacks and misrepresentations.

I signed a petition supporting a group pursuing a new investigation. While I do not agree with everything they are saying, I do feel an investigation is warranted.

You, on the other hand, have been an active participant in the war crimes of Desert Storm contributing to the deaths of 1.5 million Iraqis. Do the so called "militants" hate us for "our freedom" OR DO THEY HATE US BECAUSE WE DESTROYED THEIR COUNTRY AND KILLED THEIR LOVED ONES. There is no question in my mind why you are so hostile to any type of investigation which would examine the possible wrong doings of our government and military. I hope you and Norman "bombed them back to the stone-age" Schwarzkopf get what's coming to you.

Your joining that group says you agree with their conclusions--which is why there are very few, if any, actual engineers and scientist subscribers.
As for your rant on the military, you have now fully shown the truther colors.
The ONE defining characteristic of all "troothers" is that they cannot conceive of anyone doing anything for reasons other than fear or money. All the conspirators are afraid to step up, fearing that they might loose their jobs. AAll the victims were paid off, guaranteeing their (continued) silence.Altruism and heroism are foreign concepts. They cannot imagine anyone hating something so much that they are willing to kill themselves and others to rid the world of that something. To them, the US (specifically G. Bush) is the source of all evil in the world, an evil that did not exist anywhere prior to January 2001.
I despair that they will ever join reality, but it's a WoW world for them...

 

[pomeroo]

Your joining that group says you agree with their conclusions--which is why there are very few, if any, actual engineers and scientist subscribers.
As for your rant on the military, you have now fully shown the truther colors.

The ONE defining characteristic of all "troothers" is that they cannot conceive of anyone doing anything for reasons other than fear or money.

Perfect. Absolutely, completely, 100% dead-on correct! Bullseye, RW!

All the conspirators are afraid to step up, fearing that they might loose their jobs. AAll the victims were paid off, guaranteeing their (continued) silence.Altruism and heroism are foreign concepts. They cannot imagine anyone hating something so much that they are willing to kill themselves and others to rid the world of that something. To them, the US (specifically G. Bush) is the source of all evil in the world, an evil that did not exist anywhere prior to January 2001.
I despair that they will ever join reality, but it's a WoW world for them...

 

[Par]

Beachnut... [y]ou... have been an active participant in the war crimes of Desert Storm...

You seem to be of the opinion that the coalition’s reversing of Saddam’s annexation of Kuwait was nothing short of a war crime. Is this really what you believe?

 

[R.Mackey]

Ah, politics, the death of many a scientific inquiry...

I would humbly submit to the membership that it is possible for Gregory's mathematics to be correct, and his motivation to investigate benign, independent of his accuracy in estimating casualties or appreciation of the fine points of international law.

Some of the attacks against him are mean-spirited. It would have been better, Gregory, to respond in Politics, or even not at all, but I can't entirely blame you because I don't think you started it this time.

Follow-ups to Politics. There are a lot of strong feelings on W and the Iraq War in general. Let's not conflate them all, please?

 

[Par]

Ah, politics, the death of many a scientific inquiry...

I was merely taken aback by what I found to be a rather alarming remark. But you’re quite right. I shouldn’t have contributed to derailing the thread.