Sunday, December 1, 2013

Example 2 of Relevant Evidence of the WTC Collapses that NIST did not Investigate: Free Fall of WTC7

In their final report on the collapse of WTC7 NIST offered a computer simulation of the collapse, based on the assumption that the acceleration of the collapse was 40% slower than free fall.  However, during the technical briefing of the report high school physics teacher David Chandler made it clear that there was actual free fall during the collapse of about 2.25 seconds.  In other words, there was a period of time when there was no support for the building and it fell at gravitational acceleration.  NIST revised its report to show that there actually was a period of free fall.

WTC7: NIST Finally Admits Freefall:




But NIST failed to revise their computer simulation to show how free fall could have occurred.  As the following video demonstrates the simulations they do provide would not have resulted in free fall:




What NIST needs to do is go back and try to simulate the actual free fall period that did occur.



HT: 911speakout.org and 9/11debunkers.blogspot.com

39 comments:

JDB said...

Interestingly, something similar was just posted on the Randi forum, and is currently being discussed:

http://forums.randi.org/showthread.php?t=269767

As with most forums, most of the comments aren't very helpful; I'd say the comments by "16.5" and "ozeco41" are among the more interesting and directly relevant.

JDB said...

An earlier thread is here:
http://forums.randi.org/showthread.php?t=261007

JDB said...

Now they've merged the two threads here:
http://forums.randi.org/showthread.php?postid=9672714#post9672714

Bilbo said...

Thanks for the links, JDB. If 16.5's argument is that buckling columns would have resulted in free fall, then that simply wouldn't have been the case. Even buckling columns offer resistance (which is why they are buckling). Absent columns would result in free fall. Couldn't find a comment by ozeco41 that seemed relevant.

JDB said...

"If 16.5's argument is that buckling columns would have resulted in free fall, then that simply wouldn't have been the case. Even buckling columns offer resistance (which is why they are buckling). Absent columns would result in free fall."

I assume you are referring to the following comment: "During Stage 2, the north face descended essentially in free fall, indicating negligible support from the structure below. This is consistent with the structural analysis model which showed the exterior columns buckling and losing their capacity to support the loads from the structure above."
Because these measurements are by nature imprecise, as a layperson I wonder about margins of error, the meaning of words like "negligible," and so on. Testimony from a layperson like yourself doesn't help much. This would be an excellent instance of a case where someone challenging the official story should follow my wise advice of either (i) becoming an expert or (ii) consulting an expert not part to this dispute! I look forward to the results of your inquiry.

Also, I remember back in the day when the truther claim was much bolder, involving free fall for the whole descent (and I can't remember if there was/is a free fall claim for the twin towers as well, and how that has fared on the Internet). The claim was: this is exactly what you would expect in a controlled demolition! And now it's more limited to 2.25 seconds... and still exactly what we would expect? This has made me somewhat jaded.

"Couldn't find a comment by ozeco41 that seemed relevant."
I think the claims by ozeco41 I had in mind were (i) that the free fall was only for part of the building and the related claim that (ii) "I've never seen any truther explain HOW you can get "free fall' by use of explosives. They seem to take it for granted....", which seems to be a recurring theme on the Randi forum.

A related claim is made by jaydeehess, who writes that "AE911T simply contends ffa requires CD but can present no study of structural failures indicating that ffa is specific to CD and cannot occur without the use of explosives."


Of course, you know what I think of my own ability as a layperson to adjudicate this dispute...

JDB said...

jaydeehess has also occasionally posted commentary which is relevant. For example, here:

http://forums.randi.org/showthread.php?postid=9675435#post9675435

One of his basic claims is that, because the free fall period occurs after the initiation of the collapse, it is actually unreasonable to make any confident claims about how to explain this particular interval. Insofar as uncontrolled (pardon the pun) historical events are not created in a lab environment, this seems independently plausible. But I wonder whether experts have weighed in on this particular objection.

JDB said...

ozeco41 now has an additional comment which is relevant:
http://forums.randi.org/showthread.php?postid=9675621#post9675621

JDB said...

Here's another one, from jaydeehess:

http://forums.randi.org/showthread.php?postid=9675708#post9675708

Bilbo said...

JDB: Because these measurements are by nature imprecise, as a layperson I wonder about margins of error, the meaning of words like "negligible," and so on. Testimony from a layperson like yourself doesn't help much. This would be an excellent instance of a case where someone challenging the official story should follow my wise advice of either (i) becoming an expert or (ii) consulting an expert not part to this dispute! I look forward to the results of your inquiry.

But the burden of proof is on those who claim that the buckling columns provided only negligible support. If that is what NIST wants to claim (and they never did make such a claim), then they must demonstrate it. That is what a proper investigation would have involved.

The claim was: this is exactly what you would expect in a controlled demolition! And now it's more limited to 2.25 seconds... and still exactly what we would expect? This has made me somewhat jaded.

You're jaded because you refuse to think for yourself. What you should ask yourself is: "Since even NIST admitted that there was actual free fall, how do they go about explaining how that free fall came about?"

"I've never seen any truther explain HOW you can get "free fall' by use of explosives. They seem to take it for granted....", which seems to be a recurring theme on the Randi forum.

First, the point of my posts is to demonstrate that NIST did not do a proper investigation. So far, it appears that I have succeeded in doing that.

Second, speaking as a layperson, it seems to me that one could achieve free fall by destroying the connections of all the building supports simultaneously. All the structure that is supported by them would then begin falling simultaneously, with nothing to stop them from gravitational acceleration.

A related claim is made by jaydeehess, who writes that "AE911T simply contends ffa requires CD but can present no study of structural failures indicating that ffa is specific to CD and cannot occur without the use of explosives."

So let the studies begin, by both NIST and Truthers.

Of course, you know what I think of my own ability as a layperson to adjudicate this dispute...

I know what ability you would have if you thought about the dispute.

Bilbo said...

jaydeehess: Explaining a short period of acceleration near 'g' (both above and below) is of academic interest to a small group. 9/11 conspiracy theorists and 9/11 conspiracy debunkers. That's about it!

I personally see no particular use for knowing, let alone hypothesizing, the minutia of a time period of 2.25 seconds in a collapse that had started 15+ seconds earlier. By that time the dynamic interactions within the structure are quite chaotic. There is no way to truly determine what was specifically happening inside the structure either. How anyone could possibly get details correct beyond what the NIST fea illustrated , with any confidence in its veracity, is beyond me.


If this is NIST's position, then they should say so, instead of confidently offering their computer simulation as an explanation of what really happened. But what should be clear to even laypeople is that in order for WTC7 to experience free fall of 2.25 seconds, all or almost all supports would have had to have been disconnected simultaneously for about 100 feet. Is NIST able to simulate how this could have happened without a controlled demolition?

Bilbo said...

jaydeehess: NIST was tasked with finding out what caused the collapse in order to determine if changes to codes could be made to lower the chance of a similar occurance. There is nothing in the dying moments of such a chaotic sequence that is of any use to that task.

If NIST is unable to simulate the free fall period, then why think that they discovered what caused the collapse?

Bilbo said...

jaydeehess: All that aside , did you ever address my point concerning the data that shows that the points measured achieved greater than free fall acceleration? It indicates quite clearly that there must be something other than simple 1d vertical forces and motions involved and that thus it follows that AE911T's simple 1d analysis is of no value.

If there really was greater than free fall acceleration, then gravity alone was not the cause of the collapse and NIST's explanation is false. Propellent by explosives could explain greater than free fall acceleration.

JDB said...

"the burden of proof is on those who claim that the buckling columns provided only negligible support. If that is what NIST wants to claim (and they never did make such a claim), then they must demonstrate it. That is what a proper investigation would have involved."
This is pretty disappointing. I raised an intelligible question that immediately arises upon hearing your categorical claim about the free fall number. Margins of error and imprecision would strongly undercut the confidence with which layperson such as yourself endorse the controlled demolition thesis. And in any case, deciding this question is necessary for deciding whether another investigation is needed in the first place.

"You're jaded because you refuse to think for yourself. What you should ask yourself is: "Since even NIST admitted that there was actual free fall, how do they go about explaining how that free fall came about?"
I gave a perfectly intelligible reason why I find the online truther community decreasingly trustworthy - and trust in sources if important, because I am a layperson. Polemical psychoanalysis doesn't help much here.

"the point of my posts is to demonstrate that NIST did not do a proper investigation. So far, it appears that I have succeeded in doing that."
The idea that an extremely brief self-published blog post by a layperson has succeeded in undermining an expert report would need to be underwritten by defenses of the many assumptions called into question in the statements I've been referring/linking to. Asserting your own success is unhelpful.

"it seems to me that one could achieve free fall by destroying the connections of all the building supports simultaneously. All the structure that is supported by them would then begin falling simultaneously, with nothing to stop them from gravitational acceleration."
What seems to you as a layperson is irrelevant to a technical question like this one. If you are aware of a serious reply to this challenge, let me know. Think of the background here: the truther movement regularly simplifies controlled demolition information for lay audiences, to an extreme degree, and often begins their discourses with the premise that the event is "obviously" a controlled demolition. The straightforward challenge that a key piece of evidence - free fall - is not characteristic of controlled demolition, would, if true, seriously undercut controlled demolition as an alternative explanation of the event. (And would correspondingly bolster NIST's claim that controlled demolition was not credible enough to warrant comparable investigative resources - which would weaken your claim that free fall poses a serious problem for their theory.)

JDB said...

"So let the studies begin, by both NIST and Truthers."
This simply isn't germane, because the statement you're responding to was precisely one which undermines a key premise in arguments for the controlled demolition hypothesis - a premise which underwrites the very value of investigating the particular hypothesis in question. As I've explained many times, an important part of science (not mentioned in your previous superficial characterizations of science) is first deciding what is worthy of pursuit and what isn't.

"I know what ability you would have if you thought about the dispute."
I do think about the dispute, but I know in my own field of research that when laypeople (even intelligent ones, like Dawkins or Coyne) attempt to adjudicate expert disagreements they go very badly off target - and quite consistently so. And this in a field much murkier and prone to error than the hard sciences. This is a, but not the only, motivation for my principles of lay epistemic responsibility, which I've clearly laid out many times.

And I should say, this little exchange here has itself lowered my credence in your lay reliability (which is not personal, because it really means: the reliability of your preferred online sources). You frequently seem to have no answer for even moderately informed criticism of your position, but instead either attempt to psychologize me or refer to your personal seemings, or some other underwhelming response. It shouldn't be that I'm able to cast serious doubt on your position with a short amount of time spent on an only medium-quality online forum. Yet it seems like this is what is happening. That you don't have replies for these apparently well-known critiques of trutherism is kind of surprising, so maybe you just don't have the time. But then the question arises: why are you so comfortable posting over-simplified, vague posts like this one, without informing your audience of the major doubts about these arguments?

6373e914-5f55-11e3-bf39-000bcdcb471e said...

This last statement is incorrect.

The pull of the collapsing interior applied to the exterior adds downward force, which can cause the walls to accelerate downward faster than g.

Explosives would not apply force downward unless they were built like rockets, shaped intentionally to send the building downward. Aside from being senseless, there is no evidence for such devices.

Bilbo said...

JDB: And in any case, deciding this question is necessary for deciding whether another investigation is needed in the first place.

We know that free fall refers to the rate of acceleration of unsupported objects. If NIST wants to claim that the building achieved free fall, even though their simulation shows substantial support for the building, they need to explain why we should expect free fall. But as far as I know, NIST has never bothered to address this question at all. If that is correct, then we have good reason to believe that NIST never did a proper investigation.

Polemical psychoanalysis doesn't help much here.

An intelligent layperson is often able to sift and evaluate evidence from both sides of a debate to see points are important. They do not dismiss one side merely because they find some of their arguments invalid or untrue. You don't seem willing to do that. Hence my psychoanalysis of you has validity.

The idea that an extremely brief self-published blog post by a layperson has succeeded in undermining an expert report would need to be underwritten by defenses of the many assumptions called into question in the statements I've been referring/linking to. Asserting your own success is unhelpful.


I've answered your objections and the objections of those you have referred me to. I have good reason to claim success.

What seems to you as a layperson is irrelevant to a technical question like this one. If you are aware of a serious reply to this challenge, let me know.

It's not clear to me that the challenge is a serious one. Even if there are no other cases of free fall CDs, it doesn't demonstrate that there couldn't be. For the challenge to be serious, it would need to be demonstrated that there is good reason why there couldn't be. But I think a survey of CDs would be helpful. And I think miniature CDs
could probably be carried out by the Truthers to bolster their claim.

This simply isn't germane, because the statement you're responding to was precisely one which undermines a key premise in arguments for the controlled demolition hypothesis - a premise which underwrites the very value of investigating the particular hypothesis in question.

Wait a minute. You want the Truthers to prove a negative (that free fall cannot take place without CDs)? I suggest that you're the one who doesn't understand how science works. We can expect Truthers to do a survey of CDs to see if others had experienced free falls. We can hope that they try miniature CDs of their own to see if they can achieve free fall. They have presented arguments that free fall can only be achieved by removing all supports simultaneously, and that the only known process for doing this is CDs. But to demand that they prove that no other method can achieve it? Get serious.

Bilbo said...

673...The pull of the collapsing interior applied to the exterior adds downward force, which can cause the walls to accelerate downward faster than g.

Only if the pull is something more than gravitational force. Otherwise, there is no additional force to make the downward acceleration faster than g.

If acceleration was faster than g, then we should look for some other force beside gravity. As unlikely as it seems, explosives could be one of them.

6373e914-5f55-11e3-bf39-000bcdcb471e said...

No, the force of the pull does not have to exceed gravity, just the force of the resistance. The force due to the weight of the exterior is already provided to pull the exterior downward - weight is just the pull of gravity against a resisting force, such as the ground. Once the pull of the interior exceeds the resistance to collapse, the exterior falls, and at the interior continues to apply pulling force.

The force balance equation looks like this, in the direction of the pull of gravity:

(Force of Pull) - (Force of Resistance) + (Pull of gravity) = (Total Force)

Bilbo said...

637 wrote:
(Force of Pull) - (Force of Resistance) + (Pull of gravity) = (Total Force)

Exactly. But since in NIST's explanation the Force of Pull is caused by the Pull of Gravity, the Total Force will not exceed the Pull of Gravity.

6373e914-5f55-11e3-bf39-000bcdcb471e said...

I don't think you get it. The exterior is standing and under stress from the interior collapse connections (beams and girders) yanking downward. When the outer columns finally give in with a collection of snaps, the added force is still there, yanking down. When you add that to the acceleration to the fall, you can get over g acceleration. The yank downward does not go away when the columns break, it's still yanking downward and adding to the force of the fall.

Bilbo said...

But the "yank downward" is caused by the pull of gravity. There is no additional force being added to the force of the fall, which is also caused by the pull of gravity.

6373e914-5f55-11e3-bf39-000bcdcb471e said...

True, it all comes from gravity. However the weight of the interior is now pulling down on the exterior, adding force. since F=ma, that force adds acceleration, once the columns break on the exterior due to all the added force plus the weight of the columns. The combined acceleration from the pull added to the g acceleration of the weight of the columns, minus the resistance at the bottom, can exceed g. It is a simple stack up of forces.

JDB said...

Bilbo, you live near several major research universities. Why not ask an expert independent to this dispute about your little debate with 637...?

JDB said...

"If NIST wants to claim that the building achieved free fall"
Why do you keep putting the claim in this misleading way? Isn't the claim that a part of the building achieved around free fall for an isolated, small part of the collapse, the total duration of which was slower than free fall? And, related: isn't this counterevidence to the controlled demolition hypothesis, since no one has showed that it's what to expect in a controlled demolition?

"they need to explain why we should expect free fall."
This is only true if the data of the free fall period is (i) an anomaly and (ii) a problematic anomaly. You haven't answered any of the questions about margins of error, the fact that models are always idealized, the idea that it's unreasonable to expect an explanation to cover every detail of a complicated event like this one, and so on. Answering those questions in an evidence, research-based way is necessary for showing that NIST has failed in some way here. What I'd be interested in from you is the results of you exploring this with an expert or two who are not party to the dispute.

"then we have good reason to believe that NIST never did a proper investigation."
This depends, of course, on answering the previous questions, but it also depends on additional issues, like: (i) what the point of the NIST study was (e.g., to achieve an unprecedented level of detail in modeling an historical event?); and (ii) whether there are credible explanatory alternatives which don't inherit more or worse anomalies or explanatory burdens. Your superficial, brief post by nature can't address these sorts of issues, dealing with which is nevertheless necessary to establishing your point.

"to sift and evaluate evidence from both sides of a debate to see points are important."
As you can see from my participation on both here and the Randi forum, I am very able to present both sides of this. Oddly, something close to "zero" of your posts on this topic give your readers any sense that there is intelligent disagreement with your position.

JDB said...

"They do not dismiss one side merely because they find some of their arguments invalid or untrue."
I'm not sure what this line is in response to. You might be accusing me of some form of ad hominem. Something like: Truther literature is constantly misleading and littered with basic errors, therefore all of their claims are false. But that's not something I think. Rather, I think a layperson navigates expert disputes largely based on trust (e.g. it's because of a form of epistemic trust that truther petitions are even supposed to be relevant). What I'm saying is that this has been undermined for me over the years, and that your blogging practices don't help.

"I've answered your objections and the objections of those you have referred me to. I have good reason to claim success."
But many of your responses are either (i) ad hominem; (ii) re-assertion; (iii) negation; or (iv) grounded by prefaces like "It seems to me...".

"Even if there are no other cases of free fall CDs, it doesn't demonstrate that there couldn't be."
The claim I have in mind is the constant claim (e.g. in literature you've recommended or given to me, in the course of doing so harming the credibility of your position) that free fall in fact is characteristic of CD. If it's not characteristic of CD, then this considerably lessens the force of pro-CD arguments.

"You want the Truthers to prove a negative"
No, this isn't philosophy - I don't need anyone to "prove" a negative. But negative claims - constantly made by truthers - can be defended with evidence and research. And should be - especially when this negative claim is essential to justifying further investigation.

In any case, it's a little hard to understand the current version of trutherism, since I guess it has to be that it was important for part of the building to achieve something close to free fall for 2.25 seconds in the middle of the collapse, and for the rest of the building not to be in free fall - and it's not clear to me whether the claim is still that this was due to controlled demolition or not. Again, the claim used to be that the whole building fell in free fall - and that this was what you'd expect in a controlled demolition. Why this doesn't seriously undermine the scientific trustworthiness of those who defended this claim is unclear to me.

Bilbo said...

637:
The combined acceleration from the pull added to the g acceleration of the weight of the columns, minus the resistance at the bottom, can exceed g. It is a simple stack up of forces.

Let's go back to your original equation:

(Force of Pull) - (Force of Resistance) + (Pull of gravity) = (Total Force)

If the Force of Pull were something separate from the Pull of gravity, then we have a separate force that we add to the Pull of gravity. For example, let's say that Superman were pulling down on the interior columns and walls. Then we have a force in addition to gravity. Then acceleration could (and given Superman's strength, no doubt would) exceed free fall.

But (according to NIST) there is no separate force from gravity. We have gravity pulling down on everything at the same time and with the same force. It's pulling down on the exterior of the building. It's pulling down on the interior of the building. In our F=MA calculations, F=the pull of gravity. There's no other force to add to it.

Now if A is greater than free fall, then some additional force besides gravity is at work, and NIST's theory is falsified.

Free fall is the greatest rate of acceleration that gravity can achieve. If acceleration is greater than free fall, then something more than just gravity is at work.

Bilbo said...

JDB: Isn't the claim that a part of the building achieved around free fall for an isolated, small part of the collapse, the total duration of which was slower than free fall?

NIST claims that there were three stages to the collapse. If I remember correctly,the first and third stages were slower than free fall, and lasted about 3.2 seconds. The second stage lasted about 2.25 seconds. The question is how did it achieve free fall for about 40% of the fall?

And, related: isn't this counterevidence to the controlled demolition hypothesis, since no one has showed that it's what to expect in a controlled demolition?

It would be counterevidence if we knew that it was contrary to what we should expect in a controlled demolition. But is it? I've been told by someone who was involved in demolitions that the columns are cut at an angle, so that once the explosives go off, the top and bottom parts of the columns will slide past each other. This seems to suggest there will be some resistance (at least from friction) between the upper and lower parts of the columns until they have moved past each other. If so, then we would expect the first stage of the fall to be slower than free fall. We would expect the last stage of the fall to be slower than free fall, since the upper part of the building is now colliding with the debris at the based of the building. So what is left is the middle stage. It seems that if all the columns are cut simultaneously on numerous, consecutive floors, then we should expect that there will be no resistance to impede free fall.

This is only true if the data of the free fall period is (i) an anomaly and (ii) a problematic anomaly.

It's a problematic anomaly. For falling objects to achieve free fall, there must be no resistance below them (other than air). So for a building to collapse for any amount time at free fall, there must be no resistance below it for that time. How does it come about that an entire building can have no resistance below it? NIST's model shows columns buckling below while the building is falling. If NIST wants to maintain that this resistance is in fact negligible, they need to at least do the calculations necessary to show that it is negligible.

You haven't answered any of the questions about margins of error, the fact that models are always idealized, the idea that it's unreasonable to expect an explanation to cover every detail of a complicated event like this one, and so on. Answering those questions in an evidence, research-based way is necessary for showing that NIST has failed in some way here.

David Chandler claimed there was free fall for 2.25 seconds. NIST went back and did their own measurements (measuring from the middle of the top of the building, instead of the northwest corner as Chandler had done) and agreed that there was free fall for 2.25 seconds. So neither party is in dispute about this. Only third party bloggers dispute it. NIST didn't revise their simulation to show no resistance. Instead, they claim that the resistance of the buckling columns was negligible. Very well. At leas do the calculations to show that it was negligible.

What I'd be interested in from you is the results of you exploring this with an expert or two who are not party to the dispute.

Sure, if I ever get time, I'll do that. You are at a university. Have you thought of exploring it with an expert or two yourself?

I'm out of time for today.

JDB said...

"I'm out of time for today."

How could anyone have something more valuable to do than regurgitate minority claims in an expert dispute, on a self-published blog?

6373e914-5f55-11e3-bf39-000bcdcb471e said...

There is nothing magical about the original source being gravity for the interior fall. The simple fact is, a force is being applied to the exterior. When the exterior support fails, the wall falls under it's own weight, however the original force being applied is still there. so the forces add up, and when you divide out the mass of the wall you get the resulting acceleration. at that point, the acceleration can be anything, depending on the force applied. Below g, over g, at g, doesn't matter. This is as basic as physics gets. Gravity may have supplied the original energy, but the force is the force. divide the mass out, and you get the acceleration. you are imposing an artificial limitation on what the acceleration of something can be.

JDB said...

"But the burden of proof is on those who claim that the buckling columns provided only negligible support. If that is what NIST wants to claim (and they never did make such a claim), then they must demonstrate it."

You don't think NIST thinks that, by the time this stage of the collapse occurred, the columns were providing negligible support?

Bilbo said...

JDB: How could anyone have something more valuable to do than regurgitate minority claims in an expert dispute, on a self-published blog

"Regurgitate?"

Bilbo said...

637: you are imposing an artificial limitation on what the acceleration of something can be.

I thought about it afterwards and realized that you are correct. So if someone thought (as neither NIST nor Chandler thinks) that the building exceeded free fall acceleration, then they could argue that the source was some interior mass applying enough force to cause it. If NIST is correct, then this mass had, if I remember correctly, about 1.7 seconds plus whenever someone thinks greater than free fall acceleration occurred. If Chandler is correct, then it had less than 1.7 seconds. If someone thinks that the exterior of the building was uniformly exceeding greater than free fall acceleration, then this mass was applying the force uniformly. Sounds a little improbable.

Bilbo said...

JDB: You don't think NIST thinks that, by the time this stage of the collapse occurred, the columns were providing negligible support?

I won't venture to speculate on what NIST thinks. They claim it was negligible. So let them do the calculations to show that it was negligible.

JDB said...

"Regurgitate?"
Not like penguins do with their food, but otherwise, yes - insofar as it comments on the collapse of various towers, your blog seems to merely repeat the most basic outline of material from other people. And you don't even bother regurgitating the best-known objections from informed commentators to this material, or explaining to your readers that much of the material you link to is irrelevant or debunked, and that you only intend them to take seriously a part of what you're linking to.

"I won't venture to speculate on what NIST thinks. They claim it was negligible. So let them do the calculations to show that it was negligible."
I meant "think" interchangeably with "claims." You said quite directly, "they never did make such a claim," which was curious to me since the claim is explicitly incorporated into their report.

6373e914-5f55-11e3-bf39-000bcdcb471e said...

The apparent uniformity of the exterior collapse is due in large part to the moment frame construction, which holds the exterior together in a manner akin to surface tension, for these purposes. In any case, you are looking only at one side, and it even tented in at the top edge as it was.

Bilbo said...

JDB: but otherwise, yes - insofar as it comments on the collapse of various towers, your blog seems to merely repeat the most basic outline of material from other people. And you don't even bother regurgitating the best-known objections from informed commentators to this material, or explaining to your readers that much of the material you link to is irrelevant or debunked, and that you only intend them to take seriously a part of what you're linking to.

Sorry, JDB, but I pretty much limit my time on the computer to an hour a day, so I don't have time to comb through all that bloggers have to say about things. But if the few comments you have referred to me are an example of the best that they have to offer, then I would say that I haven't missed much at all. Perhaps there are better objections that you have been saving up? I'd be glad to hear them. Or do you think my regurgitations have fallen short? If so, please feel free to point out how.

I meant "think" interchangeably with "claims." You said quite directly, "they never did make such a claim," which was curious to me since the claim is explicitly incorporated into their report.

Their simulations also show columns that are not falling, but are buckling, which means that they are offering resistance. Since NIST claims the resistance is negligible, then it's up to them to show why.

Bilbo said...

637: The apparent uniformity of the exterior collapse is due in large part to the moment frame construction, which holds the exterior together in a manner akin to surface tension, for these purposes.

Perhaps.

In any case, you are looking only at one side,...

Ah, sweet irony. To be told that my view is limited by someone whose view cannot be seen at all.

...and it even tented in at the top edge as it was.

Danny Jowenko took this as further evidence that that it was a controlled demolition. In a typical CD, it is important to start the demolition in the middle, so that the building falls inwards. Of course, that doesn't mean that you don't also need to take out the exterior columns. It means that you take them out slightly later.

But in your scenario, apparently you don't need to take them out at all? A little extra force to the inner columns will make the whole thing come down uniformly. If only demolition experts knew about this it could save them so much time and trouble.

Meanwhile, since NIST has failed to provide a simulation that models your hypothesis, what reason do we have for taking your hypothesis seriously?

Anonymous said...

Danny Jowenko said WTC 1 and 2 were not CD. He got 67 percent right. 911 truth is holding at zero percent right.

Bilbo said...

Mr. Jowenko ended his discussion on WTC1 and 2 by saying that they could be brought down by CD, but that it would take a long time to set it up. It isn't clear what he meant by a long time. Nine months?

Whether or not the 9/11 Truth Movement is correct about it being an inside job, I think they have demonstrated that there has been an inadequate investigation of the event.