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William Seger
(11,031 posts)... then showing that it's nonsense would conclude the debate, wouldn't it?
T S Justly
(884 posts)No longer any debate among those with two working eyes and a nose to sniff out
the stench informing the Offal-CIAl Story. We know it was a multi-building
demolition project using chemical and human agents. I'm guessing the Military had
operational control and authority that day, as I'm guessing it still has.
William Seger
(11,031 posts)The problem for the "truth movement" is that Cole's odious bullshit doesn't stand up so well with people who also employ their brains.
Example: Cole claims that molten aluminum is silvery in color, not glowing orange like the stuff seen flowing out of the building. It's amazing that someone with an engineering degree is apparently unaware that, while aluminum is silvery at it's melting point, it will glow just like any other metal if it's heated above it's melting point.
Example: Cole shows the video of the fireman saying he saw "molten steel." The fireman never says why he assumed it was steel when there are far better guesses available (e.g. aluminum or even glass), but since it's absurd to think that steel melted by therm*te when the buildings were destroyed would still be molten weeks later, this particular piece of "evidence" seems to only appeal to people who haven't actually given it any real thought.
Example: If therm*te had been used to destroy the buildings, the debris pile should be full of steel showing thermite-like melting. In fact, even though the steel was inspected by private-citizen, volunteer engineers and scientists who saved "interesting" pieces, there is not a single piece of any such evidence of thermite cutting or melting. Instead, Cole shows us a sample that he must know is the result of a eutectic, sulfidization reaction that took place at a temperature of only about 1000 degrees C over a period of hours or days, so it is cetainly not the result of thermate burning. Cole should know that because that was the conclusion of the study from which he obtained that photo.
Example: Cole shows the iron-rich microspheres found in the dust and claims them to be the product of therm*te burning. In fact, the lightweight concrete used in the building included fly ash, which is full of iron-rich microspheres produced in incinerators. In fact, there are many other possible sources, such as the welding that was done to erect the building. So, if anyone wants to claim that there are also microspheres produced by therm*te when the towers were destroyed, they need to start by explaining how they separated out those microspheres from the ones that we know were already in the building. For some strange reason, "truther scientists" like Cole and Jones completely duck that issue, too.
Example: Cole informs us that the "peer reviewed" Harrit/Jones paper found nanothermite in the dust. In reality, what the data in that paper shows that the stuff does not look like or behave like any known form of thermite, so these scientific geniuses "conclude" it must be some sort of mysterious secret, military, "highly engineered" supernanothermite. After completely failing to do the types of tests that could have proved any thermitic reaction at all occurred (i.e., that their samples weren't simply burning in air, which they certainly appear to be doing), or that such a reaction was even theoretically possible (e.g. whether or not there was any elemental aluminum present rather than aluminum oxide), the paper offers up conclusions that aren't even supported by the data it does present! As the paper itself pretends to admit then refute, the most obvious explanation is that they are simply looking at paint chips, yet the paper's section that purports to rule out paint is astonishingly inadequate even to non-scientists: These "scientists" didn't even bother trying to find out what kind of paint was used in the building! Instead of looking in the NIST report to find that, Jones scraped some paint off of BYU's stadium bleachers and says, nope, not the same stuff. DUH! And then we find out that the chips are chemical identical to the rustproofing paint used on the floor joists! Don't you think an intellectually honest person should be embarrassed by that? But no, these "truthers" refuse to give up their "peer reviewed" paper after having paid to have it published. But when a paper is that absurd, the issue of whether or not it had any "peer review" is moot, since abject horseshit obviously survived whatever review it may have had.
There's a lot more that could be said about that one video, but that's more than enough to make this point: If the debate is over, T S, then it's because "truthers" have walked away from it, leaving a shitload of issues and unanswered questions about their claims. Most people take that as a concession, T S.
T S Justly
(884 posts)Although, it certainly proves out a superior solution to what brought the complex down
than NIST "science" provides. And, because controlled demolition can be the only conclusion to reach, imo, and, from my perspective, the least bizarre, I must again reject the Government's conclusions and thus its theories. Independent researchers are doing the best work and providing the best explanations for the problems that continue to plague all the issues surrounding the events of 9-11.
After people start seeing the real truth, the false propaganda and fake science they've seen and heard daily since 9-11-2001 begins to take on all of the importance and relevance of wall paper. And, further, the Bush Theory Movement has a double disadvantage to overcome. The first part is the people who were in charge when everything happened. They are liars and mass murderers by way of invasion and rationale. They are provably fascists, with their titular head being the ideological and biological grandson of a WWII Nazi. They are, in fact, prime suspects. The second part is NIST's laughable attempts to side-step Sir Isaac and physical law.
But I'll say this. It must be tough to be in the shoes of someone in the Bush Theory Movement, unless he's getting paid. And, if that's the case, I'd tell him or her to keep digging, you're almost there, lol. Later.
zappaman
(20,612 posts)Is that all you got?
You make a good case for why the truther movement dies a little more every day....
T S Justly
(884 posts)William Seger
(11,031 posts)T S Justly
(884 posts)
OnTheOtherHand
(7,621 posts)Nu?
If you think you can rebut NIST, why on earth don't you?
T S Justly
(884 posts)OnTheOtherHand
(7,621 posts)That's already been rebutted. If you disagree with the rebuttal, you can make arguments on your own behalf. Otherwise, Seger wins the argument hands down.
"I saw it on the Intertubez" is not an argument that inspires confidence.
T S Justly
(884 posts)My argument is the Chandler series, which is the subject of the OP. Which has not been
rebutted in the least, despite your arrogant insistence that it has. As for the irony, independent
research is no good because it's posted online, but, Government and sympathetic followers' crap
that appears online is gold. Do I have that right? Lol!
OnTheOtherHand
(7,621 posts)Any of us can read your response to Seger's post #6. You didn't lay a glove on it. You can go back and address that, or I suppose you can try to change the subject.
research is no good because it's posted online, but, Government and sympathetic followers' crap
that appears online is gold. Do I have that right?
Why, no, no you don't. Obviously, some independent research is good, some is bad, and some is a mixed bag. As we all can see, Seger didn't argue that the video is fallacious because it is "independent."
wildbilln864
(13,382 posts)"Example: Cole claims that molten aluminum is silvery in color, not glowing orange like the stuff seen flowing out of the building. It's amazing that someone with an engineering degree is apparently unaware that, while aluminum is silvery at it's melting point, it will glow just like any other metal if it's heated above it's melting point. "
Can you please give evidence for this false assertion? At what temperature does Al begin to glow like any other metal? 
shouldn't you guys be arguing that it's Pb and not Al?
Bolo Boffin
(23,872 posts)At the temperature that all metals glow orange. Aluminium's melting point is far below other metals, but the color spectrum of heated metals applies to it like any other metal. It's one of the requirement to be a metal.
wildbilln864
(13,382 posts)
isn't this then accurate?
Bolo Boffin
(23,872 posts)Ace Acme
(1,464 posts)and turn orange? Not even NIST tries to claim that. They claim it's bits of flaming contaminants in the aluminum.
But the fact of melted steel in the rubble pile contradicts that. "I saw melting of girders" said Dr. Abolhassan Astananeh-Asl, a professor of structural engineering at Berkeley.
GoneFishin
(5,217 posts)It's typical of someone who is really not concerned with what HE believes is true, as long as he can convince YOU that it is true. It's like it is some kind of mission or something.
William Seger
(11,031 posts)... when he doesn't know what he's talking about.
"Truthers" are known for their hypocrisy. It's like it is some kind of mission or something. It seems that you are less than half-informed about the nature of black body radiation.
> It's typical of someone who is really not concerned with what HE believes is true, as long as he can convince YOU that it is true.
Do you happen to have a shiny aluminum mirror? Someone who was actually concerned about whether or not molten aluminum can glow red might have spent a couple of minutes searching Google images, which is where I found lots of examples like these:
GoneFishin
(5,217 posts)William Seger
(11,031 posts)I see plenty of pictures of hot aluminum glowing red, orange, and yellow bright enough to appear white in photos -- pretty much as predicted by the theory of black body radiation. On the other hand, I see you pretending to know some secret physics that refutes that theory. Seems to me you're the one who could use some luck with peddling that bullshit.
wildbilln864
(13,382 posts)posted earlier. What is the temp of the metal flowing from the building here?
1100 C ?
1200 C ?
Bolo Boffin
(23,872 posts)We have no way of ascertaining what exact color that is because of camera issues, color correction, being in shadow vs. being in direct sunlight, etc. But to be glowing like that at all means it's pretty darn hot.
Now I get your Pb comment. Yes, I'm one of those who thinks that's actually lead with other debris from the Uninterrupted Power Supply room that was in that precise location in the building -- lead batteries in the heat of one of the major fires in the South Tower liquefying in their cases until they burst and flowed out.
wildbilln864
(13,382 posts)would reflect sunlight much and all as it's emitting it's own light & the pictures and videos show the molten metal flowing from the building to be very bright almost white. I don't think it Pb either! It remains silvery also until raised above what temp? 
Pretty darn hot indeed though! I'd guess maybe 1100-1200 C minimum!
Bolo Boffin
(23,872 posts)wildbilln864
(13,382 posts)it's actually brighter than in the pics?
wildbilln864
(13,382 posts)have that same characteristic?
Ace Acme
(1,464 posts)Where did you get your information that it does?
If the concrete contained fly ash, why would they leave dozens or hundreds of tons of useless iron in it?
William Seger
(11,031 posts)... depending on whatever is most readily available and cheapest in the area. Along the East Coast, that is fly ash by a wide margin, because while there are thousands of coal-burning power stations, there are very few exposed volcanic flows. In fact, most of the pumice used as aggregate on the East Coast is shipped in from the Greek island of Yali in the Mediterranean.
> If the concrete contained fly ash, why would they leave dozens or hundreds of tons of useless iron in it?
Because it wasn't until the '90s or so that people started going to the trouble of magnetically removing the iron.
Ace Acme
(1,464 posts)But that did not stop you from declaring emphatically "In fact, the lightweight concrete used in the building included fly ash."
What was your source for this information? Did you just make it up? Did you rely on the unsupported claims of anonymous internet propagandists?
How can you expect anybody to believe anything you say?
Given the vast bulk of the necessary admixture, shipping in from Greece or removing unnecessary iron would have been worth the trouble.
William Seger
(11,031 posts)... in the dust and in the lungs of first responders.
The fact that there is apparently no record of the formula for the lightweight concrete is actually the reason I'm quite sure that fly ash was used: The contractor would not have gone to the extra expense of using pumice unless the engineers had explicitly specified it, and apparently they didn't. I don't find that surprising, since in my five years as a structural draftsman on the East Coast (Alexandria), i never heard of a single building where pumice was specified.
So, yes, I do have reasons for believing that it is a fact that the WTC concrete contained fly ash. Prove me wrong.
Ace Acme
(1,464 posts)So how do we know how the fly ash got there? Maybe the guy lived on a toxic dump site.
Gosh, show your confirmation bias much?
Fly ash found in the dust?
Gee, does fireproofing compound have fly ash in it?
Gee, does drywall mud have fly ash in it?
Gee, does drywall have fly ash in it?
Gee, does spackle have fly ash in it?
Gee, does tile grout have fly ash in it?
Gosh, show your confirmation bias much?
You didn't answer the question. What was your source for the emphatic claim that "In fact, the lightweight concrete used in the building included fly ash"? Are you ashamed of your sources?
William Seger
(11,031 posts)... is any mention of pumice, so let's add that to the list of reasons I've already given you. I have already acknowledged that it appears the composition of the concrete was not documented, but a specification of pumice would have been documented since it's more expensive and uncommon on the East Coast.
While it's true that absence of evidence is not evidence of absence of pumice in the mix, let's review for a moment where the burden of proof really lies here: If someone wants to argue that the iron spherules must be the result of thermite burning, as Jones & Co do, then by the principle of parsimony they are obliged to prove that they didn't come from more a more mundane source, and simply refusing to acknowledge that the concrete is the most likely source doesn't do the trick. Extraordinary claims, Occam's Razon, and all that.
Ace Acme
(1,464 posts)to separate out a mineral of no particular interest?
It's not like specimens of concrete were particularly rare. There were some chunks--some must have been almost 8" in diameter. If you want to claim that the microspheres came from the concrete, it's for you to assay the concrete and find out.
What if all of these tests that NIST "forgot" to do were actually done and they decided to suppress the results because they were not to the Department of Commerce's liking?
And you STILL didn't answer the question. What was your source for the emphatic claim that "In fact, the lightweight concrete used in the building included fly ash"? Are you ashamed of your sources? Did you have no sources? Where did you get your extreme confidence of something you apparently can't demonstrate? Did you get it from some authority figure? Divine inspiration? The back of a cereal box?
William Seger
(11,031 posts)The report documents glass fiber, plate glass, and leaded glass, but no volcanic glass.
I no longer remember where I first read that fly ash was used the concrete, and I can't now find any authoritative source. However, I told you why it agreed with what I know about common lightweight concrete at that time, from personal experience as a structural draftsman in the early '70s. Nonetheless,even if that information is incorrect, the issue is that there are multiple possible sources of fly ash and iron spherules in the dust, and the important thing from a scientific point of view is that Jones & Co did nothing whatsoever to identify those sources and rule them out. I'm sorry you don't understand why that would be necessary, but that's irrelevant.
Ace Acme
(1,464 posts)You are the one making claims--that they were in fly ash in the lightweight concrete--that you can't prove.
William Seger
(11,031 posts)... and you don't understand why the burden of proof is on Jones & Co that the spherules were produced by thermite, then you are manifestly unqualified to discuss the subject. But that's never stopped you from posting ad nauseum before, has it.
Ace Acme
(1,464 posts)here.
I'm interested in the burden on you,which you utterly failed to fulfill. You said the slabs used fly ash, but you provide no evidence of it. You provide evidence that ONE first responder had fly ash in his lungs, but we don't know when his exposure was or how. Maybe he lived in an ash pit.
Why would lightweight concrete incorporate many thousands of tons of useless weight in the form of iron microspheres?
William Seger
(11,031 posts)It must be frustrating to be so compulsively argumentative and yet be wrong so often, and I doubt that anyone is surprised to learn that you don't actually give a shit about the issue.
Ace Acme
(1,464 posts)The miscrospheres remain open.
It's those like you who demonstrate by your willingness to invent your facts that you don't give a shit.
I am not interested in the mysteries being solved by anonymous internet posters in obscure chatrooms. I am interested in having a qualified investigation with subpoena power free of the corrupting influence of the Bush administration.
William Seger
(11,031 posts)... but I have told you why I accept it, and you have given me no reason not to. You say it's not your problem that Jones & Co can't rule out any of the obvious possible sources of the spherules -- you don't even want to know what they are -- but you think there very existence warrants another investigation because you don't know where they came from. All I can say is, don't hold your breath.
Ace Acme
(1,464 posts)wildbilln864
(13,382 posts)gyroscope
(1,443 posts)For the remotest chance of bringing down a steel building with fire, the structural steel of the ENTIRE building would have to be exposed to the flames not just a few floors at the top. The entire building would have to be engulfed in flames for days if not weeks. Burning a few floors at the top for less than an hour isn't going to do it.
OnTheOtherHand
(7,621 posts)Part of the problem here may be ambiguity about the phrase "with fire." You appear to think that it is impossible for a collapse initiated near the top of a building to lead to the destruction of the entire building, but you didn't say why. (Also, you appear to have discounted the damage done by the collisions.)
gyroscope
(1,443 posts)* the weight of a small block cannot pulverize a much larger, heavier block to dust within a matter of seconds.
* You don't see stacks of floors piling up on each other like pancakes do you?
What you see is the towers exploding to bits as they come to the ground.
That indicates explosives.
OnTheOtherHand
(7,621 posts)There is no need for the upper floors to "pulverize" the lower floors. They only have to do enough damage for the lower floors to fall. How much pulverization occurs is a separate issue.
Fallacy of the excluded middle? The top floors were about a quarter of a mile high. That's a lot of gravitational potential energy. I wouldn't have expected the concrete to stack neatly.
That indicates explosives.
I'm not sure what you mean. What I see is a lot of building materials breaking up, which seems unsurprising given that lots of collisions are occurring in a short time.
If you're suggesting that there is video evidence that explosives were used to "pulverize" the concrete, (1) I don't think so, and (2) I don't understand why anyone would plant explosives to pulverize the concrete. Is that a common controlled demolition practice?
gyroscope
(1,443 posts)I think the towers were too tall to bring down by conventional demolition/conventional means.
so they had to use more powerful explosives to pulverize the floors one by one.
the sheer height and mass of these towers were too great, they would not collapse neatly into a small pile using conventional demolition. There's probably a limit to how high a skyscraper can be for conventional CD to work. Above a certain height, conventional CD will fail to bring it down neatly. I'm no expert on CD but that's my theory which I think its reasonable.
Bolo Boffin
(23,872 posts)The towers didn't do this.
Anyone who can look at pictures of Ground Zero and think "neatly into small pile" isn't considering all of the facts.
gyroscope
(1,443 posts)I don't think you can ever make a building that tall fall neatly into a small pile, regardless of CD techniques.
but only relatively neat compared to regular conventional CD.
using conventional CD would probably make them topple over!
the goal is to make the pile as small as possible.
Bolo Boffin
(23,872 posts)In the case of the WTC towers, if this was the goal, then the demolition people failed.
"using conventional CD would probably make them topple over!"
No. That's another common misperception that the 9/11 Truth Movement uses to make its point. To topple over, those buildings would need a pivot point able to support the entire weight of the building as it developed enough lateral motion to topple. The way the buildings were built, individual connections in any potential pivot point would have failed before toppling could happen.
Ace Acme
(1,464 posts)William Seger
(11,031 posts)Bolo didn't say "buildings can not topple"; he said, "The way the buildings were built, individual connections in any potential pivot point would have failed before toppling could happen." Whether or not a building can be made to topple like the ones in your video depends completely on the construction details. The toppling buildings shown in the video are actually trying to rotate around their center of mass. If there is enough lateral resistance available at the pivot point to allow pushing the center of mass past the edge of the building, then it can be made to topple. Otherwise, it can't, regardless of what caused the initial collapse: If whatever is being pushed against collapses, the toppling cannot proceed. (That's a valid example of Newton's 3rd Law, btw.)
Ace Acme
(1,464 posts)And this is all explained to us by our patient anonymous internet propagandists.
For your next trick you can explain why a 747 is too big to take off, because those little elevators in the rear can't possibly lift the nose wheel off the ground.
William Seger
(11,031 posts)1) You have a peculiar reaction to being wrong; and 2) you really shouldn't undertake arguing about structural mechanics. As I said, it depends on the construction details of the particular building, and in the case of all three WTC buildings, I'm not guessing: We have Finite Element Analysis simulations that show that the columns could not resist lateral forces sufficient to allow toppling.
Ace Acme
(1,464 posts)William Seger
(11,031 posts)Ace Acme
(1,464 posts)... that the columns could not resist lateral forces sufficient to allow toppling"?
Where do you have that?
William Seger
(11,031 posts)The sims show that when the buildings started to tilt, the pivot points were pushed in the opposite direction. The reason is explained by Bazant et al.:
without explosives, the towers would have had to topple like a
tree, pivoting about the base (Bažant and Zhou 2002 Fig. 6b or
6c). This hypothesis was allegedly supported by the observed
tilt of the upper part of the tower at the beginning of collapse
Fig. 6a. However, rotation about a point at the base of the
upper partFig. 6c would cause a horizontal reaction approximately 10.3 greater than the horizontal shear capacity of the
story, and the shear capacity must have been exceeded already at
the tilt of only 2.8° Bažant and Zhou 2002. Thereafter, the top
part must have been rotating essentially about its centroid, which
must have been falling almost vertically. The rotation rate must
have decreased during the collapse as further stationary mass accreted to the moving block. So, it is no surprise at all that the
towers collapsed essentially on their footprint. Gravity alone must
have caused just that (Bažant and Zhou 2002)
Ace Acme
(1,464 posts)resist lateral forces sufficient to cause toppling. I asked you to where was that FEA and you started talking about the towers.
You're blowing stinky smoke, as usual.
William Seger
(11,031 posts)When the top of WTC 7 starts to tilt toward the south, the base of falling section kicks toward the north because the columns could not resist the lateral force. And 2) that's why the lower part of the building fell on the Verizon building, so the sim is accurate.
Ace Acme
(1,464 posts)The sim animations bear no resemblance to reality.
The Verizon building was to the West. How does kicking to the north cause damage to the west?
William Seger
(11,031 posts)... if you're observant, but it's easier to see what's happening with this view from the west:
> The Verizon building was to the West. How does kicking to the north cause damage to the west?
Hey, congratulations! You were right about something! I should have said the Irving Trust and 30 West Broadway buildings:
Ace Acme
(1,464 posts)of the collapse.
William Seger
(11,031 posts)The towers began tipping immediately when one perimeter wall collapsed, exactly as would be expected by the fact that one wall was no longer holding up its end. Your statement isn't just contrary to what the videos show; it makes no sense whatsoever.
You continue to say that the sims "bear no resemblance to reality" based on completely superficial appearances while willfully ignoring the underlying physics that the sims demonstrate -- i.e. the entire purpose of the sims. But then, you continue to demonstrate that you aren't very good at simple observation, either. These two frame grabs clearly show that the rotation of the south tower kicked the bottom of the falling block in the opposite direction, and Bazant's calculation shows why the lateral force involved was far in excess of what the structure could withstand:
Of course you can continue to assert your "bear no resemblance to reality" claim forever; you just shouldn't expect to be taken seriously.
Ace Acme
(1,464 posts)When I asked you ('cause I've seen the animations and they don't show tipping to the south) you presented a still image of WTC7.
When I complained that the WTC7 sims don't resemble reality, you changed the subject to the towers.
There is nothing superficial about the disconnect from reality in the WTC7 sims that show the building folding up like a wet paper bag.
You are blowing smoke. Stinky brown smoke.
William Seger
(11,031 posts)I am not responsible for your poor observation skills. As I said, it's easier to see in the view from the west that the building is tipping toward the south which causes the base of the falling section to be pushed north, but it CAN be seen in the animation:
And, of course, the tipping can be seen in the actual collapse videos, despite your "no resemblance to reality" assertions.
Your desperation to win some debating point while ignoring or dodging the underling issues is becoming rather tiresome.
Ace Acme
(1,464 posts)I observed how you were all over the place, showing still pictures instead of animations, changing the subject from WTC7 to the towers.
What was the point again? That towers can not topple? And yet here you show it tipping! And why do they cut off the animation when they do? Because it's about to topple! It's tipping to the south, the s. wall is disintegrating faster than the north wall is accordioning,
So after all your song and dance and handflapping, you're proving my point!
William Seger
(11,031 posts)The point was that whether or not a building can be made to topple over like a tree depends completely on the construction details of that particular building -- specifically, whether or not the pivot point can withstand the lateral forces generated.
The still rendering is from the same sim as the animation, "Ace," and both show what I was talking about. I thought that view from the west might help you see what you apparently didn't see in the animation, but I forgot to take into account your willful blindness and your sad desperation to win a debate point. Suit yourself.
Ace Acme
(1,464 posts)Your own video shows that the pivot point does not shift. The north wall accordions. The base is not shifted. The part of the wall above the accordion is not shifted. The building leans to the south as you say, and it's just about to topple, because the south wall is disintegrating. But NIST pulls the plug on the animation, because that would too obviously show that their sims bear no resemblance to reality.
William Seger
(11,031 posts)I can't force you to see it or to understand it, but it's hard not to notice that you are deliberately avoiding the physics: When the top section tips, it is trying to rotate around its center of mass, and for a building to topple over like a tree, the structure that its pivoting on must be able to resist the lateral force that's pushing in the opposite direction. That means that whether or not a particular building can resist that lateral force depends entirely on the construction details of that building. If you had understood that before your post #132, you wouldn't have attacked a straw-man:
> Oh how nice to have Bolo to explain to us why bumblebees can not fly and buildings can not topple.
You can't actually argue against the substance of what I'm saying but your ego won't let you admit that you didn't understand the physics involved, so you'll keep posting over and over and hope nobody notices. It's a tiresome game.
Ace Acme
(1,464 posts)Your own video does not not show a shifting pivot point.
Thanks for another substanceless post that shows you don't know what you're talking about.
William Seger
(11,031 posts)... is as irrelevant as your inability to comprehend it.
And the substance of my post is all that stuff you deliberately ignored for reasons that are pitifully obvious.
Ace Acme
(1,464 posts)This is before the accordioning that takes place in the animation--but even so, it does not show what you claim. There is no shift of any pivot point. The walls at the ground floor remain where they were, and the building is toppling.
On what grounds do you put the pivot point at floor 8? You could just as well put it at floor 17. Didn't you say the building rotates around its center of mass?
And you're still refusing to say where you get this nonsense. Are you ashamed of your sources? You're just making this stuff up, and substituting attitude for substance.
William Seger
(11,031 posts)... is as irrelevant as your inability to see it. You didn't know why some buildings might topple like a tree while others might not, and now you simply refuse to understand it, as if that will save you from looking foolish. I think I've explained quite clearly that I "get this stuff" from valid physics and from close observation of both the sims and the collapse videos, and as usual, all you've got is a wall of denial. Until you can do better than that, there's nothing left to discuss here.
Ace Acme
(1,464 posts)Oh, you get your stuff "from valid physics". Wow, that's very very impressive sourcing!
You refuse to answer simple questions. On what basis do you place the pivot point on floor 8?
You said the rotation was around the center of mass. Is floor 8 the center of mass?
William Seger
(11,031 posts)The rotation was around the center of mass; the pivot was the columns that were still supporting the top when the columns on one side failed.
I'm sure I've encountered people with less aptitude for mechanics and physics than you, but I can't recall when I last saw someone so eager to flaunt it. I literally laughed out loud when I saw your post in GD about "those versed in the laws of physics." It's hard to believe you could be so oblivious to how much you are embarrassing yourself.
Ace Acme
(1,464 posts)When you refuse to answer it shows that you don't know what you're talking about.
William Seger
(11,031 posts)... and you've failed to comprehend what I'm saying well enough to come up with anything resembling a cogent reply, much less a rebuttal. You are the one -- perhaps the only one on the entire board -- who doesn't know what I'm talking about. But I'll keep bumping the thread for as long as you care to continue embarrassing yourself.
Ace Acme
(1,464 posts)You ignore questions and change the subject.
zappaman
(20,612 posts)
Ace Acme
(1,464 posts)with another devastating Hallmark bromide.
zappaman
(20,612 posts)By the way, are you enjoying your latest stay?
GoneFishin
(5,217 posts)it seems clear that it means that the writer concludes. It reads like the writer is light on proof and heavy on prevarication.
My opinion is that they could try to reproduce those nice symmetrical collapses by asymmetrical damage to a building 100 times, and they would end up with 100 crooked, lop-sided heaps, with 50% of the building still erect. No way would they fall so neatly and completely even once, never mind 3 times in one day.
If it is that easy to get a building to fall straight down, why have trained demolition companies? I guess anybody who knows how to light a fuse can go into that business.
Gullible.
William Seger
(11,031 posts)... but if you don't understand the simple physics of what Bazant was saying, it's hard to understand why you think anyone who does understand it should take your opinions seriously.
> If it is that easy to get a building to fall straight down, why have trained demolition companies? I guess anybody who knows how to light a fuse can go into that business.
That's the same kind of nonsense that Steven Jones put in his first infamous paper. In fact, you need someone with a lot of training to make a building fall where you want it to instead of falling straight down and sending debris in every direction like the towers did.
GoneFishin
(5,217 posts)those here who have no training in the sciences, but since you make that allegation with no knowledge of who you are writing to, I can conclude that is simply a tactic to shut people up who you don't agree with.
I realize you will keep flinging stuff at the wall hoping that something will stick.
Good luck with that.
William Seger
(11,031 posts)He's describing a principle of physics that I first observed when I was a little kid stacking blocks, but didn't understand until I took physics in high school -- all of which was many decades before Bazant wrote that. Apparently, you missed class that day.
gyroscope
(1,443 posts)we see building 7 brought down in a very conventional CD manner.
unlike the north and south towers the floors, were not pulverized one by one from the top.
thats probably because building 7 is small enough where conventional CD is sufficient to bring it down.
building 7 was only 47 stories versus the towers at over twice height at 110 stories each.
OnTheOtherHand
(7,621 posts)I agree that the collapse of WTC 7 looks more like controlled demolition than the collapses of the twin towers. But I don't think it looks very much like controlled demolition, there is no need to postulate explosives in order to account for the collapse, and there is no obvious reason to demolish it anyway.
I realize there are people in the world who think that the NIST analyses are obviously wrong because, well, the NIST analyses are obviously wrong. There isn't much I can say about that.
gyroscope
(1,443 posts)At the time of its destruction, Building 7 housed documents relating to numerous SEC investigations. The files for approximately three to four thousand cases were destroyed, according to the Los Angeles Times. Among the destroyed documents were ones that may have demonstrated the relationship between Citigroup and the WorldCom bankruptcy. 2
Perhaps even more interesting than the loss of these case files is the fact that WTC 7's collapse destroyed the OEM's command center on the 23rd floor.
--------------------
Bush did a huge favor for his Enron and Wall Street buddies.
Or it could have been just a lucky coincidence for them that the
SEC was conveniently wiped out along with all records of its on-going cases.
Building 7 is the smoking gun, a classic standard controlled demolition if there ever was one. By any reasonable measure from what I can see. What makes you think it wasn't?
OnTheOtherHand
(7,621 posts)You don't seem deeply committed to the premise that destroying some SEC documents merits demolishing a 47-story building. In truth, it isn't very persuasive. Chucking in the OEM doesn't help very much.
SEC was conveniently wiped out along with all records of its on-going cases.
You're asserting that the entire SEC was housed in WTC 7?
You haven't presented an iota of evidence that the collapse of WTC 7 was a controlled demolition, "classic standard" or otherwise. I don't ordinarily believe things without an iota of supporting evidence.
gyroscope
(1,443 posts)....fires that were ignited by the falling debris of Tower 1. Bldg 7 was not struck by any aircraft. The idea that a few random, isolated fires is somehow sufficient to cause the building to collapse straight-down in exactly the manner of a standard CD seems quite absurd.
http://www.nist.gov/public_affairs/factsheet/wtc_qa_082108.cfm
Going back to my previous post because the same idea applies.
But especially applies in regard to Building 7 since it was not hit by any aircraft:
-----------------
4. For the remotest chance of bringing down a steel building with fire, the structural steel of the ENTIRE building would have to be exposed to the flames not just on a few random floors. The entire building would have to be engulfed in flames for days if not weeks.
-----------------
More info:
The official explanations of WTC 7's collapse are problematic for several reasons:
* Fire has never caused any steel-framed high-rise building to collapse in any manner, let alone with the vertical precision of Building 7's destruction. 1 Other steel-framed skyscrapers have experienced far more serious fires than Building 7.
* WTC 7 fell straight down, which necessitated that all of the load-bearing columns be broken at the same moment. Inflicting such damage with the precision required to prevent a building from toppling and damaging adjacent buildings is what the science of controlled demolition is all about. No random events, such as the debris damage and fires envisioned by the official reports, or explosions from fuel tanks proposed by some, could be expected to result in such a tidy and complete collapse.
* WTC 7 fell precipitously, at a rate closely approaching the speed of gravitational free-fall. That necessitated the sudden removal of structure near ground level that would have impeded its descent.
* The collapse of WTC 7 exhibited all of the features of a standard controlled demolition. To suppose that a cause other than controlled demolition could produce an event with all of the features uniquely characteristic of controlled demolition defies logic.
http://911research.wtc7.net/wtc/analysis/wtc7/index.html
----------------------------------
Bolo Boffin
(23,872 posts)That's called a straw man argument.
You make several other unsupported assertions in this post.
"The structural steel of the ENTIRE building would have to be exposed to the flames not just on a few random floors."
Not at all. Based on professional computer modelling of WTC 7's actual structure, localized fires around Column 79 could have brought the whole structure down in just the way it fell.
"all of the load-bearing columns be broken at the same moment."
Not at all. 79 went first, taking 80 and 81 with it. Then the core columns failed, and then the perimeter columns failed. Not even the perimeter columns failed at the same time. The kink began developing in the roofline before the corner 9/11 Truth like to focus on started to fall. This was a progressive collapse, where load-bearing columns failed in rapid succession to each other.
"WTC 7 fell precipitously, at a rate closely approaching the speed of gravitational free-fall."
Gravitational free-fall is a measure of acceleration, not speed. Furthermore, that acceleration rate happened for only a couple of seconds within an 18-second collapse. There was plenty of resistance in the other 16 seconds.
"all of the features of a standard controlled demolition."
This is manifestly untrue.
gyroscope
(1,443 posts)Let me post it one more time for you.
again, from NIST:
How did the fires cause WTC 7 to collapse?
The heat from the uncontrolled fires caused steel floor beams and girders to thermally expand, leading to a chain of events that caused a key structural column to fail. The failure of this structural column then initiated a fire-induced progressive collapse of the entire building.
According to the report's probable collapse sequence, heat from the uncontrolled fires caused thermal expansion of the steel beams on the lower floors of the east side of WTC 7, damaging the floor framing on multiple floors.
Eventually, a girder on Floor 13 lost its connection to a critical column, Column 79, that provided support for the long floor spans on the east side of the building (see Diagram 1). The displaced girder and other local fire-induced damage caused Floor 13 to collapse, beginning a cascade of floor failures down to the 5th floor. Many of these floors had already been at least partially weakened by the fires in the vicinity of Column 79. This collapse of floors left Column 79 insufficiently supported in the east-west direction over nine stories.
The unsupported Column 79 then buckled and triggered an upward progression of floor system failures that reached the building's east penthouse. What followed in rapid succession was a series of structural failures. Failure first occurred all the way to the roof line-involving all three interior columns on the easternmost side of the building (79, 80, 81). Then, progressing from east to west across WTC 7, all of the columns failed in the core of the building (58 through 78). Finally, the entire façade collapsed.
http://www.nist.gov/public_affairs/factsheet/wtc_qa_082108.cfm
----------------------------------------
Do you need to read that again? Please, take your time.
Because it couldn't be any clearer.
Bolo Boffin
(23,872 posts)And I've spelled out a number of ways you misrepresented it. Please leave off the sarcasm and start representing the report correctly.
gyroscope
(1,443 posts)the report is so comical and absurd on its face even the staunchest official story supporters like yourself are too embarrassed to acknowledge it.
I would be too.
Bolo Boffin
(23,872 posts)of the NIST report, we'll continue this talk.
OnTheOtherHand
(7,621 posts)"a few random, isolated fires" -- that's what I call argument by adjective. It's convenient because it doesn't require any actual knowledge of the issues, but it is inherently unpersuasive for the same reason.
It's tendentious to assert that WTC 7 collapsed "straight-down in exactly the manner of a standard CD." By default, things fall down, not sideways. If you intend to offer reasons to prefer your idiosyncratic explanation(?) of WTC 7's collapse to NIST's, then a good approach would be to find observables that are better explained by your hypothesis than by NIST's -- not mere similes.
Yes, you said that the structural steel of the entire building would have to be exposed to the flames, and I pointed out that you hadn't supported this assertion. Now you're repeating it. I do not construe repetition as evidence.
Most of those pasted talking points have no apparent bearing upon the "official explanations." For instance, arguing that WTC 7 must have been blown up because other skyscrapers have withstood more intense fires is sort of like arguing that the Challenger must have been blown up because O-rings can function at temperatures far below freezing. It's logically possible that for a particular building to survive a particular fire would undermine NIST's analysis, but as a handwaving generalization, the argument fails.
I'm not sure this is stated clearly enough to be worth attempting to rebut. If this is the crux of the argument, then we can try to sort it out.
Then the irreparable damage to Fiterman Hall is evidence against controlled demolition, isn't that true?
Nonsense. In a standard controlled demolition, people can see and hear explosives going off -- and, might I add, generally the structure isn't undergoing uncontrolled fires. I know that David Chandler has convinced himself that he can hear explosives going off, but even if we assume that he is right, the fact that he is struggling to make his case years after the event underscores just how unlike a "standard controlled demolition" the collapse of WTC 7 was.
Nuclear Unicorn
(19,497 posts)Ace Acme
(1,464 posts)zappaman
(20,612 posts)"I'm no expert on CD but that's my theory which I think its reasonable."
OnTheOtherHand
(7,621 posts)As Bolo pointed out, the towers didn't collapse neatly. Beyond that, I don't understand why neatness would be a goal, nor why pulverizing the floors would be, nor why you think you're seeing explosives pulverizing the floors one by one, nor why you think it would have been possible to place enough explosives to pulverize the floors one by one.
So, I cannot tell why you believe this happened.
gyroscope
(1,443 posts)it did not collapse 'neatly.' but neatness is also a subjective and relative term.
'neatness' or relative 'neatness' would be a goal because you have to control of the collapse pile 'or the crime scene' so to speak.
if the debris field is too spread out that is not good because you lose control of the crime scene. you want to have control of the evidence. you cant have reporters and random members of the public picking up pieces of the buildings to keep for themselves that they can later use as evidence against you or use to discredit the official story. the smaller the debris field the easier you can control it.
OnTheOtherHand
(7,621 posts)Papers from the Twin Towers landed in Park Slope, Brooklyn -- so I certainly agree that neatness is a subjective and relative term. If that's the final word, then your argument fails.
At the risk of sounding facetious, I can't help but notice that the best way to prevent telltale evidence from falling into the wrong hands would be not to demolish the towers to begin with. Your argument makes sense if construed as an attempt to explain away the absence of telltale evidence. But if you really want to argue that the collapses were surprisingly neat, then you need a positive argument to that effect.
ETA: Maybe I should have written "suspiciously neat." Surprises aren't inherently suspicious, although sufficiently surprising surprises might be.
cpwm17
(3,829 posts)The large upper block struck one floor at a time on the lower block. What was under the floor that was currently being struck is minimally relevant. There is a huge force and a lot of energy being applied to that floor. As that process repeats down the building, the forces and energies increase.
The collapse wasn't perfectly symmetrical, but this is a good way to think of it.
cpwm17
(3,829 posts)The force of one floor falling on top of the next lower floor is many time the normal static weight. Even falls much less than a dozen ft would still cause the next lower floor to collapse.
The towers were simply not built to withstand such huge forces. Once the collapse started, there's no stopping it.
gyroscope
(1,443 posts)if what you're saying is true the upper block should remain intact all the way down.
but the upper block disappeared within three seconds after it started to drop.
so now you have nothing to crush the lower block with.
Secondly, you are ignoring laws of physics.
For every action there is always an equal and opposite reaction:
the floors of the upper block cannot remain intact as the floors of the lower block are being crushed. this is in violation of Newtons third law of motion. the floors of both blocks should both be destroyed. and since the lower block is much larger than the upper block, the upper block would have run out of floors before the lower block did. so it cannot possibly have the crushing force necessary to completely destroy and crush the lower block all the way down to the ground. that would be in violation of the most fundamental law of physics.
cpwm17
(3,829 posts)The upper and lower sections did destroy each other on the way down, but the majority of the mass still stayed within the buildings' columns. The loose mass broken off from both the upper and lower sections continued to strike the lower sections as the buildings collapsed. Newton's Third Law of Motion is not violated.
I'm not sure when the upper sections disintegrated completely, as the debris did block the view. But we can clearly see that the upper sections started getting destroyed immediately.
gyroscope
(1,443 posts)you say the lower block was destroyed by the falling upper block.
but now you're saying the towers were destroyed not by a falling intact upper block but by its debris which is turning to dust on its way down?
only way to explain away the official story is by twisting yourself into a pretzel.
Bolo Boffin
(23,872 posts)That's your assertion, and it's up to you to prove it.
cpwm17
(3,829 posts)Last edited Sat Dec 31, 2011, 11:17 AM - Edit history (1)
- If you want me to be perfectly accurate. The majority of the mass stayed in the column, though I don't know how much was expelled outside or above the column as debris or dust. But what was expelled was more than made up for with the accumulating debris from the lower floors.
wildbilln864
(13,382 posts)The steel frame of the building would act like a heat sink and the fires, if they kept burning would migrate from fuel source to fuel source.
gyroscope
(1,443 posts)that played the major role in bringing down the towers
thanks to the excellent experimental work of the guy in your video.
this is the first time I have seen it.
it disproves Natgeo's official story propaganda beyond a doubt.
William Seger
(11,031 posts)Obviously, there are several of us who are completely unconvinced that there was any thermate in the building -- something to do with the abject failure to present any credible evidence or rational reason for it -- but I don't believe you actually paid much attention to that video if you think "it disproves Natgeo's official story propaganda beyond a doubt." It actually fell short of even proving that a vertical column could be cut with thermate, although it did provide some examples of what sort of steel damage we should find == but don't! -- in the rubble, and it actually demonstrated how implausible it is that thermate devices were installed directly on the columns all over occupied office buildings. But no, it did not disprove anything about the "official story."
eomer
(3,845 posts)The NIST explanation depends, in part, on steel being heated to a particular point so that it was weakened and failed in various ways. NIST found no steel samples that had been heated to that point:
NIST WTC Final Report (See pages 180-181.)
So if we apply your skepticism consistently then the NIST explanation suffers from a lack of any credible evidence just as much as the thermite theory does.
William Seger
(11,031 posts)Second, the claims are not at all symmetric: We know for a fact that there were intense fires, and we know from lab tests that office fires like that can produce air temperatures of around 1000 degrees C. On the other hand, we know that the thermite hypothesis was invented out of whole cloth for the sole purpose of allowing paranoid conspiracists to imagine a silent controlled demolition, even though no such demolition had ever been attempted, simply because their previously imagined conventional demolition surely did not occur. Extraordinary claims require extraordinary evidence; mundane claims do not. The NIST claim that steel go hot enough to be weakened is credible without direct evidence, but in fact there is indirect evidence in the inward bowing of the perimeter columns.
But the biggest problem with your claim is the assertion that NIST's explanation requires columns that were heated above 600 degrees C. It does not, since their explanation for the onset of collapse is that sagging floor trusses pulled those perimeter columns inward until they buckled. You're falling for a "truth movement" strawman.
eomer
(3,845 posts)Just like no samples of the type predicted by a thermite theory were found. The two theories - the NIST collapse explanation and the thermite explanation - are on equal footing with regard to finding the physical evidence that should be there if they are true.
And regarding whether NIST's explanation requires that heating of the steel structures, they only present one single deterministic explanation. There are lots of parts to it and the parts work together (in their theory and model) to produce collapse. They don't provide any analysis for what would have happened if some parts of their explanation turn out to be wrong. Would the towers have collapsed if steel structures didn't reach the temperatures their model assumed? They don't address that question. So, yes, their explanation does require that all of its parts, including that heating of steel, turn out to be right or else all bets are off and someone needs to go back to the drawing board and redo all the analysis.
Bolo Boffin
(23,872 posts)They didn't find any samples from the segments which would have registered the higher temperatures. All the samples they found came from the cooler parts of the modelling, and they all fit the modeling.
eomer
(3,845 posts)The thermite theory predicts that some of the steel was subjected to thermite exposure and some of it wasn't. Steel that wasn't subjected to thermite was found, which fits with the thermite theory modeling.
A bit more seriously, though, I don't think that the temperature signatures of steel that wasn't in the fire zone fitting the model could really tell that much about the temperature of steel that was in the fire zone. Do you?
Bolo Boffin
(23,872 posts)And despite your assertion that it confirms the thermite model as well, there IS no specific model of the thermite hypothesis, not like the specifics of the NIST computer modeling. And the steel samples fit the computer model in specifics.
And there's visual evidence of the flooring sagging, as the heat would have caused it to do.
eomer
(3,845 posts)They collected some data. Then they worked with models until they found one that fit all of that data. One salient piece of data that they included in their criteria was that the towers collapsed. So they worked to find a model that would fit all the other data and the one most important data point of the towers collapsing.
I'm an actuary so I'm very familiar with the process of working backwards to find a set of assumptions and algorithms that produce an answer that you like. Actuaries do it all the time. That they could find such a model was a given before they even tried and it proves nothing.
edit: punctuation typo
Bolo Boffin
(23,872 posts)I'm sure you know that the main reason they collected the samples was to verify that the steel had met construction specifications, right?
eomer
(3,845 posts)What they did demonstrates nothing but mathematical modeling proficiency.
William Seger
(11,031 posts)The reason for adjusting the input parameters until the model agreed with the KNOWN behavior of the collapse is simply because if you don't do that, then there's no reason to think the model is telling you anything useful about the UNKNOWN behavior. The model was still based on real physics, so the model demonstrated that, quite contrary to "truther" claims, no laws of physics were violated by the collapses. That's an extremely important result, considering that's the starting point for "truther" fantasies about what happened. What it demonstrates is that there is no need whatsoever for bizarre, unsubstantiated theories.
eomer
(3,845 posts)NIST didn't work through the physics and see what they said. They didn't come anywhere close to doing that.
They developed a collection of mathematical models that were only loosely based on physics. Some of those models resulted in collapse and some of them didn't. For each tower they chose a model that did result in collapse over another model in their collection that didn't result in collapse.
They didn't demonstrate why the one that collapses is true and the one that didn't collapse is false. One of the two must be false (at least one, maybe both). Which is the same as saying: one of the two must violate the laws of physics. How do we know which one? You and NIST prefer it to be one and not the other but you haven't provided a demonstration why that must be the case; you simply prefer it.
William Seger
(11,031 posts)> Which is the same as saying: one of the two must violate the laws of physics.
Nonsense. If you have reason to believe that the FEA software used does not accurately model the laws of physics, then I'm afraid merely asserting it is insufficient. The report shows the input parameters that were adjusted, and all of them were just the initial conditions, which weren't known with any accuracy: Absolutely none of them involved adjusting any laws of physics, and none of them were unrealistic.
> You and NIST prefer it to be one and not the other but you haven't provided a demonstration why that must be the case; you simply prefer it.
Yes, I have given what I consider a very good reason: One matched the observed events and one didn't, and that did indeed demonstrate that no violation of the laws of physics were necessary to explain what was observed. You seem to be asking for proof of veracity that wouldn't be obtainable with any FEA model, which is not a valid criticism of any particular model over another.
eomer
(3,845 posts)The global models were used for the two final simulations and provided complete analysis of results and insights into the subsystem interactions leading to the probably collapse sequence. Based upon the results of the major subsystem analyses, impact damage and thermal loads for Cases B and D were used for WTC 1 and WTC 2, respectively. The models extended from floor 91 for WTC 1 and floor 77 for WTC 2 to the roof level in both towers. Although the renditions of the structural components had been reduced in complexity while maintaining essential nonlinear behaviors, based on the findings from the component and subsystem modeling, the global models included many of the features of the subsystem models:
-snip-
NIST Final Report, page 104.
Reducing the complexity of structural components in the model compared to the actual real world components (that are obviously not reduced in complexity) is clearly adjusting the laws of physics. The laws that apply to simplified objects are not the same as the laws that apply to more complex objects.
And regarding choosing the model that matched observed events, neither of the models can be shown to be accurate or inaccurate on any basis except for the fact that it matched (collapsed) or didn't match (didn't collapse). This is no way to demonstrate that the collapse was inevitable without any help. It is just as possible that the non-collapsing model is the correct one and that it was the help of other factors (thermite or whatever your favorite theory is) that were required to modify the otherwise non-collapsing model to make it match the observed events and collapse.
Bolo Boffin
(23,872 posts)against all available data is so unconvincing to you that your only alternative is to posit thermate in the most nebolous non-specific hypothesizing imaginable?
You understand how unconvincing that sounds to me?
eomer
(3,845 posts)The only reason to choose the one that collapses is because you prefer to see it collapse. The other one is just as rigorous and professional, it just doesn't show what you want it to show.
The entire point of this discussion, from the start, was to demonstrate (or fail to) that the collapse was inevitable without any help. There is no logic in picking one of two models that otherwise have equal merits solely on the basis that it collapses and the other one doesn't and then claim that this somehow shows that the collapse was inevitable. The reasoning is entirely circular.
Bolo Boffin
(23,872 posts)All three cases (the base case, less severe case and more severe case) are reasonable and realistic representations, each within the range of uncertainty, of the conditions in the WTC towers on Sept. 11, 2001. Of the three, the more severe case resulted in the closest agreement with the visual and physical evidence. (Refer to NIST NCSTAR 1-2, Section 7.1 and NIST NCSTAR 1-6, Section 9.2.4.)
Well, how about that?
Tell me, when will the 9/11 Truth Movement be producing a thermite model just as dynamically robust and in such close accordance with the visual and physical evidence?
eomer
(3,845 posts)then, yes, it is obviously circular.
You pick a model because it makes the tower collapse without any additional help.
You then conclude that the model demonstrates that there wasn't any additional help.
But you could just as easily have picked the model that required additional help.
Then you will have demonstrated that there must have been additional help.
The assumption and the conclusion go hand-in-hand. Obviously it is circular logic.
I'll talk to you next year. Have a Happy New Year!
Bolo Boffin
(23,872 posts)And all the modeling was within the margin of error.
Happy New Year! I hope it brings you a thermite model at least as robust as the NIST model.
eomer
(3,845 posts)I'm pretty sure you're not correct that NIST was able to establish a margin of error for all the modeling. And if they did, I'd like to know what they and you mean by "margin of error" in this context.
Since the range of their models spanned from no collapse to collapse then obviously whatever margin of error they were within (if they even established such a thing) is not something that confers confidence in the conclusions we're drawing. If it did then all the models that were within such a margin of error would give the same results for all the things we care to conclude from it.
Please let me know if you have something from NIST that explains what that is or how they established it; I'd be interested.
Bolo Boffin
(23,872 posts)What NIST said is that each of the models was within the range of uncertainty.
All three cases (the base case, less severe case and more severe case) are reasonable and realistic representations, each within the range of uncertainty, of the conditions in the WTC towers on Sept. 11, 2001. Of the three, the more severe case resulted in the closest agreement with the visual and physical evidence. (Refer to NIST NCSTAR 1-2, Section 7.1 and NIST NCSTAR 1-6, Section 9.2.4.)
It's very likely that "margin of error" and "range of uncertainty" are two completely different terms in technical language like this, and I just confused them. I had cited this above and repeat it here. The further citations to the relevant parts of the Final Report is in the answer.
William Seger
(11,031 posts)Last edited Sun Jan 1, 2012, 04:13 PM - Edit history (1)
You haven't just moved the goal posts; you've made them completely imaginary. How could any conceivable FEA model "demonstrate that there weren't other factors?"
Again, what the model appears to credibly demonstrate is that there isn't any need to imagine "other factors," because no "laws of physics" were violated, which directly refutes the "truther" claim that "other factors" need to be considered because an unassisted collapse was impossible.
So, the issue is: Can you give any cogent reason to think the model was too flawed to be a credible demonstration, or much better, since it would render the model moot, can you give any credible evidence of "other factors?" If the answer is no, then we aren't getting anywhere.
OnTheOtherHand
(7,621 posts)It's true, of course, that we can't conclude that the model is correct just because it fits the data.
However, many people appear to be convinced that the collapse of WTC 7 is inexplicable without appealing to controlled demolition. To me, that is pretty much the same as asserting that NIST would be unable to fit a model to the observables without resort to implausible assumptions. In fact, some people appear to allege that -- but I can't say that I have seen anyone demonstrate it. Most don't seem willing to argue it in detail.
It might be a "given" that one can fit a model to the observables if one is allowed to alter the characteristics of steel, the value of g, and so forth. But I don't think that is a fair characterization of the modeling task.
ETA: I should have known that WS would say much the same thing in half the space once I started my reply. Sigh. 
eomer
(3,845 posts)I think we have to parse what you mean when you say "resort to implausible assumptions". In a recent post Bolo referred to a "margin of error", which seems related.
I think these are both appeals to something that hasn't been established when you drill into it. At some level every assumption in this kind of a model is implausible and outside a margin of error. Because the model, unless it is perfect (and of course it's not), will always generate spurious results for some questions that you can put to it. So you can only make any sense of plausibility of assumptions and margin of error if you relate those concepts to some conclusion you're trying to draw from the model. Some conclusions may not depend on as much perfection in the model as others and so perhaps there might be some way to establish some kind of confidence measure and apply it, but only in the context of a particular question you're trying to answer.
That said, I don't see where NIST has done anything of the sort. The alternative models that they produced using input and algorithms that apparently fell, to them, within a range of plausibility did not all produce the same conclusion for the big question they were trying to answer. Some said collapse; some said no collapse. This seems to prove that the ranges that they considered plausible were actually not all plausible for the purposes of this question. Some of them had to be too gross of an approximation or else all the models generated by the full range would have delivered the same result for the question being asked.
And I don't think they actually established any range, explicitly, for most of the modeling input and algorithms. I have seen some range analysis for the transfer of heat from air to steel, with and without fireproofing. But that is one isolated part out of many. I've also seen a general statement to the effect that some of the variables were "within the range of physical reality" but they didn't explain any further than that and, again, such a statement does not lend itself, in any obvious way, to translation into confidence or no confidence for some particular question that is put to the model.
So I'm completely unconvinced that any relevant plausibility of assumptions or staying within some relevant margin of error has been established. But I'm totally interested in listening if you think so and want to tell me why.
Edit: minor punctuation
OnTheOtherHand
(7,621 posts)The big question, for NIST, isn't whether the towers fell down. That is known.
Nor is it whether the towers were inevitably destined to fall down once the planes flew into them. (It might be of intellectual interest to know, if one could launch the Challenger 100 times under identical conditions, whether the O-ring would fail every time, but it isn't crucial to the analysis.)
Nor is it whether *therm?te was used, although NIST finds no need for that hypothesis.
The big question, as stated in the dedication, was: "How can we reduce our vulnerability to such attacks, and how can we increase our preparedness and safety while still ensuring the functionality of the places in which we work and live?" What can we usefully learn?
Many of NIST's critics seem to entirely miss that question. It's as if some agency did extensive modeling of Katrina in an attempt to understand how to protect New Orleans, and a critic complained that the models were rigged to obfuscate the likelihood that the levees were blown up. I doubt that it is possible to use modeling to prove that the levees were not blown up, but that is a strange way of construing the entire problem.
If someone were to present evidence that ?therm*ate was smuggled into the towers, then some security recommendations might follow. Or, for that matter, someone might offer plausible security recommendations even without presenting any such evidence. That would be refreshing. But it wouldn't obviate the value of NIST's analyses.
IIRC, Case A didn't give any bowing of exterior columns at all, and Case C didn't match the observed bowing as well as Case D did. So, there's a rationale for preferring B and D to A and C that doesn't depend on the fate of the towers. (William Seger made this point, too.)
I think some of the differences among cases are directly linked to estimated measurement error (for instance, the impact speeds of the planes), while others are qualitative and/or stylized (leaving intact the top 1.2m of the core wall). If it could be demonstrated that any of these assumptions were implausible, then we might be on our way to concluding that the observed bowing prior to the collapses cannot plausibly be explained without some additional heat source.
I don't think one has to posit any sort of confidence measure, although I suppose that is one way of thinking about the problem. Given arbitrarily large computing time, one could probably rig up some stuff that behaved like confidence intervals, but I'm not sure what the point would be.
I doubt I'm really getting at your question. Oh well.
eomer
(3,845 posts)It is the first question listed in the final report abstract:
This is the final report on the National Institute of Standards and Technology (NIST) investigation of the collapse of the World Trade Center (WTC) towers, conducted under the National Construction Safety Team Act. This report describes how the aircraft impacts and subsequent fires led to the collapse of the towers after terrorists flew jet fuel laden commercial airliners into the buildings; whether the fatalities were low or high, including an evaluation of the building evacuation and emergency response procedures; what procedures and practices were used in the design, construction, operation, and maintenance of the towers; and areas in current building and fire codes, standards, and practices that warrant revision. Extensive details are found in the 42 companion reports. The final report on the collapse of WTC 7 will appear in a separate report.
NIST Final Report, page xiii.
In the body of the report there is a focus that delivers on that statement in the abstract that it would address "how the aircraft impacts and subsequent fires led to the collapse...".
In any event, if no one wants to cite NIST and its report as a demonstration that collapse was inevitable without additional help then that is fine with me. If, on the other hand, someone does want to cite the report as that demonstration then that person needs to explain how and why. It seems obvious to me that the report at best provides a range of possible answers that spans from no to yes and therefore does not provide what I would normally call a demonstration.
That's the background on which you and Bolo began saying that the assumptions and methods were within a plausible range or within a margin of error. I don't see how those terms have any meaning in the absolute, which is how you seem to be using them. They can only mean anything, as far as I can tell, in the context of a particular question or set of questions. The level of precision that would be required to predict the exact effect on one particular column, such as how it would be deformed and where it would finally rest at the end of the event would obviously be extremely exacting. Certainly there are other questions that don't require such an exacting level.
So, I agree that one doesn't have to posit any sort of confidence measure, but if one wants to demonstrate anything then one has to demonstrate something, somehow, which as far as I can see remains to be done.
OnTheOtherHand
(7,621 posts)If NIST couldn't arrive at a probable collapse sequence, then it would have much less to say about how to prevent collapses.
Correct me if I'm wrong, but you're the only one in the thread who has used the word "inevitable" at all. (True on a technicality, since I used "inevitably" -- but only in response to you, so it's not just a technicality.) So, I'm pretty lost.
I'm not sure what you're getting at in the penultimate paragraph, but I suppose that if we're considering whether an assumption is 'close enough,' we have to consider for what purpose it is close enough.
I think William Seger was essentially correct: NIST demonstrated that -- contrary to many assertions here -- the collapses are by no means physically impossible or unexplainable without controlled demolition. NIST demonstrated many other things as well.
When push comes to shove, you seem to be arguing that NIST didn't demonstrate that therm*te wasn't used. That's true, but not very interesting. I suppose you intend to argue something else, but I can't figure out what.
eomer
(3,845 posts)Although I would (and have at other times) also argue that NIST didn't demonstrate that therm*te wasn't used. Even if it were shown it wasn't needed that still wouldn't demonstrate it wasn't used. But that's not what I've been arguing in this thread. Here I've been arguing that NIST didn't demonstrate that therm*te wasn't needed.
If they had demonstrated it wasn't needed then their results would be inconsistent with that premise. But they are not. It is possible to interpret their findings as being the result of the following hypothetical facts:
- NIST's "middle" model is the more accurate one and the tower was not going to collapse without additional help.
- Additional help (therm*te or other) was present and was the reason that the observed events appear more severe than the "middle" model showed.
- NIST's "more severe" model is not the more accurate one and the reason NIST thought they needed to boost temperatures beyond their best estimate is because they weren't factoring in the additional help that was in fact present.
OnTheOtherHand
(7,621 posts)I accept that one can distinguish between whether therm*te was needed and whether it was used. I'm not sure how fruitful the distinction is.
Which premise? I do think their results are -- in a sense that is highly pertinent to the so-called Great Thermate Debate -- inconsistent with the premise that therm*te was needed, although that isn't the best way to word the point.
Maybe we can work with the Katrina analogy. It may even apply directly: I haven't read the various studies of the levee failures. I think probably the data are sparse enough that a post hoc analysis indeed would generate multiple scenarios, some of which predict the failure of the levees and some of which don't; the analysis presumably would point to vulnerabilities in the levee design. Now, imagine a group of people who argue -- in various ways -- that the levees in fact were destroyed by some form(s) of sabotage. No doubt these people will point out, correctly, that (by hypothesis) the multiple scenarios do not demonstrate that the failure of the levees was "inevitable." Maybe you can say in your own words what such an analysis, if done well, could demonstrate.
Or do you really not think it is possible for such analyses to be other than circular?
eomer
(3,845 posts)Theoretically one could solve it by the brute force, direct application of physics. Don't model anything, just calculate based on laws that are already known. But this solution is beyond anyone's capabilities, apparently.
Since that's beyond reach, then modeling is a way to approximate and simulate. But the problem is that there's no way to check the simulation against the real world. The only thing you can check it against is the same set of data that you geared it to in the first place, so it is inherently circular.
OnTheOtherHand
(7,621 posts)Even most "brute force, direct application(s) of physics" rely on simplifying assumptions. Maybe they all do. IANAE, but I think that how engineers evaluate whether their "direct" applications are valid has a lot in common with how they evaluate more complex models. In more complex models, the error sources ramify.
It's generally not the case that there is "no way to check the simulation against the real world" -- or maybe this is a semantic tangle. The NIST reports contain many examples of checking simulations against the real world. The modeling enterprise can't be definitive, but I don't think it is properly construed as "circular."
eomer
(3,845 posts)Agreed that it's not impossible to test parts of these models against the real world. But I still say that it was impractical to test them sufficiently.
In many engineering projects the models will eventually be tested "fully" do to the fact that the goal is to design and build something. By "fully" I mean that in addition to testing parts of the model along the way, they will ultimately test the whole system after it has been built. But even when tested "fully", the system may still not be tested fully.
What I mean by that is that even when they have tested the entire system multiple times, they are still sometimes wrong because their ability to test very complex things suffers from similar limits as their ability to design very complex things, which I think is related to the fact that, as you say, they are always, by necessity, using simplifications.
As an example, I'm sure that the o-rings used in the space shuttle program were extensively modeled and tested as components and the entire shuttle launch system was tested multiple times in real use before a disastrous accident made it clear that the design had flaws. The tests of the system had never included testing under the specific conditions (temperature, etc) that made the o-rings fail. Things that they didn't know made what they thought they knew from modeling and testing wrong in ways that were fatal.
And I think this is a pretty good analogy for what I'm trying to say. If the engineers designing the space shuttle launch system were not able to develop a sufficiently reliable model for a relatively simple component like an o-ring, even though they surely tested at multiple levels and stages, then I don't believe that engineers can reliably design and test a model for the WTC tower disasters, which seems to me to be many degrees of magnitude more complex.
And besides being more complex than an o-ring, the WTC tower model cannot be ultimately tested in its entirety since no one is going to build another one and rerun the disaster. In a more subtle way the space shuttle has the same problem in that even though it was built and tested it was still not possible to test it in every way that would be required to give complete assurance. So besides being much more complex, the WTC tower model can only be tested much less thoroughly than the o-ring and even so the testing of the o-ring wasn't enough to rely on it.
In much fewer words, solving this particular problem is beyond mere mortals.
Edit to add: and I need to circle back to how I still think circular logic is used regarding the WTC models, but don't have time now, will have to come back to it later.
OnTheOtherHand
(7,621 posts)Of course I agree that NIST's models can't be proven to give correct results even if the initial conditions were known with certainty, which is impossible.
I don't know that this is on point, but prior to the decision to launch Challenger, Thiokol engineers recommended against the launch in part because (1) they believed that the O-rings were affected by the cold and (2) the temperatures expected that day were outside the range of experience and testing. The managers weren't relying on engineering models that falsely indicated safety; they weren't relying on the engineers.
At any rate, the O-rings are the focus -- fairly uncontroversial, as far as I know -- of what might be called the probable destruction sequence in the Challenger tragedy. But, as far as I know, no one has demonstrated that the tragedy was inevitable given the temperatures that morning. Sabotage is a logical possibility. (The FBI even conducted an investigation -- which presumably I would denominate a "whitewash" if I thought the shuttle had been sabotaged.) Still, I think the analysis of the Challenger tragedy is pretty damn good.
I think the NIST analyses are pretty damn good, too. In my view, the analogy isn't half bad, either, although the towers are more complicated than the shuttle was.
eomer
(3,845 posts)I think the managers involved in the o-ring decisions were all engineers. I also read that the Thiokol engineers said the o-rings were safe, and that they based that on extensive testing and analysis of the tests. That's from a quick reading of this:
http://history.msfc.nasa.gov/book/chptnine.pdf
But maybe there are other sources that would dispute that account.
The decisions on the NIST modeling were also likely made by an engineer who was essentially in a manager role, weren't they?
Anyway, the point I wanted to make about circular logic is that the NIST modeling involved more than just simplifying assumptions. It's not like they modeled the input of physical objects and merely applied simplifications while remaining blind to the results that the model would produce. If they had done that and gotten close matching to observations then the match might lend some confidence to the model.
But what they did, as I recall, was to customize (not just simplify) some assumptions to be what they needed them to be to get the model to match the observations. And this wasn't just assumptions about representing the initial physical objects in the model; they actually intervened in the middle of the model to set certain intermediate results just the way they needed to be to get the results they wanted. So, for example, they set the temperatures of specific steel structures to what they needed to be to force the model to behave the same as the observations. This is why using the match of model results with observations and claiming validation from it is circular logic. The modeling is rigged up in the first place to produce such a match so the match doesn't validate anything.
OnTheOtherHand
(7,621 posts)Yes, there's more to the story than that. But it doesn't seem to be about misplaced faith in models.
You say in part,
That seems rather vaguely put. For instance, it might mean that NIST's fire models were only generating column temperatures around 400C, but the engineers realized that they needed 600C in order to get the towers to collapse, so they reached into the models, changed some 4s to 6s, and voilà! Did something like that happen, in your view?
eomer
(3,845 posts)Unfortunately the certitude rested on weak engineering analysis. Presidential commission member Richard P. Feynman, a physicist and Nobel prize winner, drove this point home after the fact. He observed that although the Center and its contractor used tests, analyses, and computer models, the standards of project officials showed “gradually decreasing strictness.” They assumed, Feynmen said, that risk was decreasing after several successful missions and so they lowered their standards. The standard became the success of the previous flight rather than the danger of erosion and blow-by. Thus a successful flight with erosion was proof of the reliability of the O-rings and justification for another launch, rather than a warning of a potential catastrophe and a sign to stop and fix the problem.
So engineers at NASA showed "gradually decreasing strictness" in order to ignore the fact that a model based on lower temperatures gave a different result than the one they wanted. That sounds familiar.
Regarding the setting of temperatures in the NIST model, yes, something like that. I need to go do some reading to refresh my memory so I'll come back later today.
eomer
(3,845 posts)Complete sets of simulations were then performed for Cases B and D. To the extent that the simulations deviated from the photographic evidence or eyewitness reports, the investigators adjusted the input, but only within the range of physical reality. Thus, for instance, the observed window breakage was an input to the fire simulations and the pulling forces on the perimeter columns by the sagging floors were adjusted within the range of values derived from the subsystem computations.
The results were a simulation of the structural deterioration of each tower from the time of aircraft impact to the time at which the building became unstable, i.e., was poised for collapse. Cases B and D accomplished this in a manner that was consistent with the principal observables and the governing physics.
There are a couple of points about this account that I want to discuss. The first is the one I said I would come back with, which is my statement that they intervened in the middle of the model and set assumptions as needed to make it match the observations. The second paragraph above is their statement that they did that. So they did not just use simplifying assumptions. They customized key assumptions, apparently down at the level of individual structures, to be whatever they needed them to be in order to make the model resemble the observations. So the model resembling the observations does not validate the model. In fact the opposite is true. The model did not resemble the observations just based on simplifying assumptions and physics. It had to be customized down at the level of individual components to make it resemble the observations, which says that the original (un-rigged) model failed to validate against observations.
Another point is their use of the phrase "within the range of physical reality". This is putting it backwards and I think putting it backwards on purpose in order to mislead. Contrary to their claim, there is no range in the physical reality of this event. The range is in the uncertainty of their models and analyses. And since the range of uncertainty spans from no to yes on the question of collapse (according to them), what their whole exercise demonstrates is the opposite of what they imply. They imply that they've demonstrated that the towers would collapse from the effects of impact and fires. In fact what they've demonstrated is that they don't know whether the towers would collapse from just those effects.
A third point is about the construction and selection of the most severe case. Apparently to construct this case they took the most severe results of each of the subsystems, combined them together, and this forms the input for the most severe case of the global analysis. Thinking of this in terms of probability, it seems they chose an answer somewhere in the tail of a distribution for each assumption and they repeated this over significant number of different assumptions. If each of the individual assumptions was on the edge of plausibility (most severe) then combining them this way would normally push the combination beyond plausibility, again from a probability point of view. In their account above you can see one revealing instance of this: they say that they discarded the less severe cases of all the subsystems because the aircraft impact results didn't match observations. How does the result for the aircraft impact subsystem justify discarding the less severe case for their heat transfer subsystem, for example, and for all the other subsystems?
So they discarded the less severe and middle cases. They also discarded all the possible combinations of the severe cases for some subsystems with the less severe or middle cases for other subsystems. Only when they combined all the marginally plausible cases for all the subsystems could they get the result they wanted.
These things taken together show that they had to push their analyses out toward (and beyond in my opinion) the limits of plausibility. And, even more than that, even if someone believes that they didn't go beyond the limits of plausibility, there is still the unavoidable fact that at best they didn't demonstrate that the towers would have collapsed; at best they demonstrated that they don't know.
Edit: remove an inadvertent smilie.
OnTheOtherHand
(7,621 posts)You seem to be reading the NIST analysis through the filter of your own concerns. There is value in reading it that way, but there are pitfalls, too.
AFAICT there isn't an "original (un-rigged) model" -- the modeling exercise was never that cut-and-dried, and was never intended to be.
I take them to mean that their adjustments of inputs were all consistent with observation. I agree that there isn't literally a range in the physical reality of the event, but there is plenty of uncertainty about the physical reality, much of which would exist even if the models per se were perfect.
Again, this seems to misunderstand NIST's basic purpose. The analysts know the towers collapsed; after extensive investigation, they believe that it collapsed from the effects of impact and fires; they don't need to demonstrate that it "would" collapse from those effects. NIST isn't obsessed with rebutting the Truth Movement or showing that the collapses were inevitable.
That would be true if each of the individual assumptions was on the edge of plausibility. I doubt that is the case.
I might try to make one or two more points, but I'm way too fried to try it tonight.
eomer
(3,845 posts)I don't see what their basis could be for believing the former without demonstrating the latter. It seems a distinction without a difference.
OnTheOtherHand
(7,621 posts)To my knowledge, no one has demonstrated that the Challenger "would" be destroyed as a result of the O-ring failure, or that the New Orleans levees "would" fail as a result of a Katrina-like hurricane. If someone is predisposed to interpret those investigations as attempts to cover up the likelihood of sabotage, nothing will prevent it. I'm half tempted to write those interpretations as an intellectual exercise, but I suspect that someone already did it seriously. (IPCC reports and associated scientific literature often are read in a similar crabbed way, which seems to obscure the actual strengths and weaknesses of the science.)
Honestly, it seems to me that the Truth Movement-inflected critiques of the NIST report have little to do with the NIST report, just as the heated critiques of the Edison/Mitofsky report had little to do with that report. They're rooted in special pleading. I'm not sure what discussion you had in mind when you wrote, "The entire point of this discussion, from the start, was to demonstrate (or fail to) that the collapse was inevitable without any help," but that's zackly what I'm talking about. That looks like reading the report first and foremost as an attempt to rebut one's preferred narrative, and responding with an attempted surrebuttal. Framing that as the "entire point" of a discussion is a formula for a useless discussion -- quite possibly worse than useless. If NIST had produced a report that was as obsessed with rebutting the Truth Movement as the Truth Movement has been obsessed with rebutting NIST, that focus surely would have detracted from other findings.
eomer
(3,845 posts)From early in the Preface of the WTC final report:
- Determine why and how WTC 1 and WTC 2 collapsed following the initial impacts of the aircraft and why and how WTC 7 collapsed;
There is no way that NIST could determine why and how the towers collapsed without at least implicitly accepting or discarding controlled demolition, the discussion of which began in the media within minutes of the first collapse.
And NIST does cite their study as showing that controlled demolition did not occur:
- the collapse was initiated in the impact and fire floors of the WTC towers and nowhere else, and;
- the time it took for the collapse to initiate (56 minutes for WTC 2 and 102 minutes for WTC 1) was dictated by (1) the extent of damage caused by the aircraft impact, and (2) the time it took for the fires to reach critical locations and weaken the structure to the point that the towers could not resist the tremendous energy released by the downward movement of the massive top section of the building at and above the fire and impact floors.
NIST WTC FAQs
OnTheOtherHand
(7,621 posts)Here's the first paragraph of Feynman's personal appendix, which immediately precedes the reference to "gradually decreasing strictness":
http://www.fotuva.org/feynman/challenger-appendix.html
NASA engineers aren't without blame, but I'm not aware that they fudged models to get the result they wanted.
eomer
(3,845 posts)Just as he finished his conclusion, Joe Kilminster asked for a five minute off-line caucus to re-evaluate the data, and as soon as the mute button was pushed our general manager, Jerry Mason, said in a soft voice, "We have to make a management decision." I became furious when I heard this because I knew that an attempt would be made by management to reverse our recommendation not to launch.
Some discussion had started between the managers when Arnie Thompson moved from his position down the table to a position in front of the managers and once again tried to explain our position by sketching the joint and discussing the problem with the seals at low temperature. Arnie stopped when he saw the unfriendly look in Mason's eyes and also realized that no one was listening to him. I then grabbed the photographic evidence showing the hot gas blow-by and placed it on the table and, somewhat angered, admonished them to look and not ignore what the photos were telling us, namely, that low temperature indeed caused more hot gas blow-by in the joints. I too received the same cold stares as Arnie with looks as if to say, "Go away and don't bother us with the facts." At that moment I felt totally helpless and felt that further argument was fruitless, so I, too, stopped pressing my case.
What followed made me both sad and angry. The managers who were struggling to make a pro-launch list of supporting data actually supported a decision not to launch. During the closed managers' discussion, Jerry Mason asked in a low voice if he was the only one who wanted to fly. The discussion continued, then Mason turned to Bob Lund, the vice-president of engineering, and told him to take off his engineering hat and put on his management hat. The decision to launch resulted from the yes vote of only the four senior executives since the rest of us were excluded from both the final decision and the vote poll. The telecon resumed, and Joe Kilminster read the launch support rationale from a handwritten list and recommended that the launch proceed. NASA promptly accepted the recommendation to launch without any probing discussion and asked Joe to send a signed copy of the chart.
The change in decision so upset me that I do not remember Stanley Reinhartz of NASA asking if anyone had anything else to say over the telecon. The telecon was then disconnected so I immediately left the room feeling badly defeated.
http://www.onlineethics.org/Topics/ProfPractice/Exemplars/BehavingWell/RB-intro/Override.aspx
One basic cause (perhaps the main cause) of the o-ring disaster was pressuring engineers to take off their engineering hats and put on their management hats. And it seems to me this is a persistent and ubiquitous problem for professionals like engineers and scientists.
Edit to add: one of the main reasons I ceased working as an actuary (my job now is Software Architect) is that all my clients wanted me to work backwards, to manipulate the actuarial methods and assumptions to give them the answer they wanted rather than my professional opinion of what the answer really was. Just wanted to disclose a personal factor that flavors my opinion on this.
OnTheOtherHand
(7,621 posts)I agree that the admonition to "put on your management hat" is damning. However, I haven't seen any evidence that the engineers rigged their models or analyses to give the results that the managers wanted. In fact, the engineers didn't say what management wanted; if they had, Lund wouldn't have been told to take off his engineering hat! When Bob Lund cast his vote to launch, he wasn't rigging a model or analysis: he was engaging in standard-issue wishful groupthink.
If I understand Tufte correctly, everyone was looking at a chronological launch-by-launch infographic that showed a bunch of O-ring problems, and a bunch of non-problems, and a bunch of temperatures, and O-ring problems at a wide range of temperatures, but nothing that focused attention on the relationship between temperature and O-ring problems. If the engineers had thought to do plot O-ring problems by temperature, as Tufte illustrates, I think they would have -- and then they might even have won their argument. Even if they had thought to sort the launches by temperature instead of chronology, they might have won.
I think there are several professionals in this forum who can empathize with your concerns about rigging analyses to reach predetermined conclusions. That empathy contributes to the intensity of the debate. Rather than try to speak for the engineers, I'll follow your lead and speak for myself: I had no predisposition or incentive discernible to myself to suppress or misrepresent evidence that the 2004 election had been stolen. On the contrary, finding such evidence would have been personally gratifying and professionally advantageous. I did not, in any way discernible to myself, prejudge any aspect of the "exit poll debate." If I had seen any sign that Edison/Mitofsky was cooking their post-election analyses, I would have taken great satisfaction in joining the howls of outrage. On the contrary, it always seemed to me that Warren Mitofsky (in particular) was much more open to following the evidence wherever it led than his heated critics were -- and I thought I had a responsibility to say so. My wife thinks that attempting to take those critics seriously, as if they were amenable to rational argument, is one of the worst mistakes I've made in my life, and she may be right. I have a lot of regrets. But I don't regret trying to get it right, and I don't regret standing up for the people who were trying to get it right.
If I understand correctly, the extensively considered opinion of several forum participants with some basis for a considered opinion is that NIST fundamentally was trying to get it right. That doesn't mean that NIST's models or analyses or conclusions are beyond critique. It means that in a contrived cage match between the folks who see NIST as cynically purveying the Official Conspiracy Theory, and those who don't, neutrality seems impossible.
As long as that contrived cage match continues, it tends to obstruct serious inquiry. The time squandered arguing that no, Michael Mann's so-called "hockey stick" from 1998 was not a perverse act of scientific fraud is time lost to ongoing climate scientific research, or even rational discussion. It is fortunate, in my view, that the 9/11 Truth Movement apparently has much less capacity to waste the time of people doing the most important building safety research -- at least, I hope that that is the case. But the critiques of Bazant and Zhou 2002 seem both as crabbed and as unproductive as the critiques of Mann et al. 1999, and that seems true of the physics arguments generally. They seem to fall into three broad categories: (1) bad arguments that non-CD collapses are impossible; (2) largely irrelevant arguments that non-CD collapses haven't been proven; and (3) strained, poorly developed arguments for alternative mechanisms. (The climate change and election fraud debates are rife with similarly fruitless approaches.) So, now what?
(edited the title for clarity: I thought the last part of your post was very much on point)
William Seger
(11,031 posts)... or that they were magical cold fires, then no, the two hypotheses are certainly not on "equal footing" when it comes to the actual evidence. That's because we certainly DO have plenty evidence for an intense fire, and we know from experimental evidence how hot those can get, and we know from experimental evidence what those temperatures do to steel. Furthermore, we have photographic evidence of the weakening and slow sagging of the floor joists and inward bowing of the perimeter columns in the towers, which "truthers" apparently cannot rationally explain as the result of thermite. On the other hand, we have exactly zero credible evidence for thermite, including zero evidence that such a demolition is even theoretically possible, and indeed there are exactly zero rational reasons to expect to find any such evidence, because the notion that the occupied buildings were rigged with thermite charges is ludicrously implausible. Extraordinary claims require extraordinary evidence; claiming that fire is hot does not. If you can call that "equal footing" because NIST didn't prove that fire is hot, then you must have a very long list of very bizarre explanations that are also on such "equal footing," but you're not really giving any rational reason to take any of them seriously OR to reject the simplest and most obvious hypothesis.
However, you specifically stated that NIST didn't have any evidence for any columns reaching 600 degrees C, and I'm telling you that's completely irrelevant because the NIST hypothesis doesn't have any need for the columns to reach those temperatures, so hopefully you will at least drop that strawman from your repertoire.
eomer
(3,845 posts)NIST chose the "more severe" models, which would be Case B for WTC 1 and Case D for WTC 2, because those models resulted in collapse. The NIST Final Report shows that the Case B and Case D models do both reflect column temperatures greater than 600 ºC. Review pages 138 through 142 and particularly tables 6-8 and 6-9 on page 141. Temperatures above 600 ºC are shown for trusses, perimeter columns, and core columns for both Case B and Case D.
William Seger
(11,031 posts)... which was the result of floors sagging.
eomer
(3,845 posts)The inward bowing of the south wall caused failure of exterior column splices and spandrels, and these columns became unstable. The instability spread horizontally across the entire south face. The south wall, now unable to bear its gravity loads, redistributed these loads to the thermally weakened core through the hat truss and to the east and west walls through the spandrels. The building section above the impact zone began tilting to the south as the columns on the east and west walls rapidly became unable to carry the increased loads. This further increased the gravity loads on the core columns. The gravity loads could no longer be redistributed, nor could the remaining core and perimeter columns support the gravity loads from the floors above. Once the upper building section began to move downwards, the weakened structure in the impact and fire zone was not able to absorb the tremendous energy of the falling building section and global collapse ensued.
NIST Final Report, pages 144-145.
William Seger
(11,031 posts)... this scenario REQUIRES 600-degree C columns.
eomer
(3,845 posts)and change them and that the predictions of the model still stand? There's no need to rerun the model and see?
Meanwhile NIST spent several pages describing these heat factors in the alternative models. Doesn't that make it pretty obvious they thought the heat factors were an important part of the model?
And, by the way, I'm pretty sure one of the differences between the collapsing "more severe" model and the non-collapsing "middle" model was exactly this heat exposure assumption.
And, finally, NIST even refers to weakening of columns due to heat exposure in that short explanation of the collapse, so they obviously think it was an important enough contributing factor to call it out.
Sorry, you can't seriously be proposing that you can change those factors in the model and still rely on the results.
William Seger
(11,031 posts)... which was the proximate cause of the collapse, according to NIST's hypothesis. The more severe fire scenario was preferred because the floor sagging in that model then matched the floor sagging that was implied by the inward bowing columns, and which was actually observed in several photos -- NOT because the more severe scenario raised the temperature of columns. I'm proposing that "weakening of columns due to heat exposure" does not "require" 600 degrees C.
eomer
(3,845 posts)I don't see how you can separate the temperatures from the rest of the model and still be left with anything.
And if you take away the models then NIST is left saying nothing at all. Everything they say is based on these models, the ones with the higher temperatures.
In a way I'm with you -- I think the models are highly suspect, especially the higher temperatures that NIST boosted up without justification other than to get the result they wanted. So I would also propose taking the higher temperatures out and I believe there are some professionals who have proposed the same. But when you do that then you are left without any model that shows collapse and the NIST conclusions all fall away.
Edit to add: Below is an even shorter explanation from NIST for why the towers collapsed. NIST mentions both the temperatures reached and the weakening of columns in this short list of things that worked together to cause the collapse. If you take away those elements then you start from scratch without any models and need to realize you are merely speculating without any foundation.
Based on its comprehensive investigation, NIST concluded that the WTC towers collapsed because: (1) the impact of the planes severed and damaged support columns, dislodged fireproofing insulation coating the steel floor trusses and steel columns, and widely dispersed jet fuel over multiple floors; and (2) the subsequent unusually large number of jet-fuel ignited multi-floor fires (which reached temperatures as high as 1,000 degrees Celsius, or 1,800 degrees Fahrenheit) significantly weakened the floors and columns with dislodged fireproofing to the point where floors sagged and pulled inward on the perimeter columns. This led to the inward bowing of the perimeter columns and failure of the south face of WTC 1 and the east face of WTC 2, initiating the collapse of each of the towers. Both photographic and video evidence—as well as accounts from the New York City Police Department aviation unit during a half-hour period prior to collapse—support this sequence for each tower.
NIST FAQs
William Seger
(11,031 posts)Some things don't require the FEA to understand. After the sagging floors pulled the perimeter columns inward until they buckled, the core was doomed, regardless of any heat weakening assumed in the model. That's because that buckling caused the top to tilt, which made the core the fulcrum of a lever: Load immediately started shifting off the opposite perimeter wall and onto the core columns. As the tilting continued, more and more of the entire weight of the upper building was shifted onto just the core columns and a few perimeter columns nearest to the buckled wall. Without any heat weakening at all, those columns would have been overwhelmed at some point by that much load -- heat weakening would just make it sooner rather than later. When those columns began to buckle, the load was immediately dumped onto adjacent columns which also failed, on across the building -- a "progressive" collapse.
> I think the models are highly suspect, especially the higher temperatures that NIST boosted up without justification other than to get the result they wanted.
Absolute nonsense. The justification was to get the same results for "key observables" as those that were actually observed in the actual collapse. Why are you having such difficulty understanding that that's about the only rational justification for thinking one of these models is more accurate than another? If you have some better justification for any other set of inputs, let's hear it.
eomer
(3,845 posts)That the floor sagging would have occurred (to the same extent) and would have resulted in collapse even without high temperatures and weakening of columns is an interesting theory but there is no model that says that. The "more severe" model (that shows collapse) included the higher temperatures and weakening of columns that you say wasn't needed. The "middle" model doesn't include the higher temperatures and weakening of columns but it also doesn't show collapse like you theorize. So you've got an interesting theory but it has no model or any other analysis that you can point to to support it.
And regarding justification for boosting temperatures, the point is that your explanation isn't the only possible one. NIST's findings are also consistent with a theory that it was their "middle" model that was the more accurate one and that rather than boost temperatures to make it collapse what they actually needed to do was to factor in additional help (from therm*te or other). This latter explanation is consistent with all their findings so they haven't ruled it out.
William Seger
(11,031 posts)... but since floor sagging was observed, that IS justification for thinking that model is more accurate. My point was that the NIST collapse scenario does not require hot columns because the core couldn't halt the collapse after the top started tilting, even without heat weakening. I believe it is possible to demonstrate that with a simple diagram showing how the tilt would move the center of mass until the entire weight of the upper building was bearing on just the columns closest to the perimeter wall that buckled. Even if we assume those columns could support three times the load that was normally on them, there is no way they could carry the entire top of the building, even if they were stone cold. Getting back to where this started, you brought up the fact that no columns were tested that showed effects of temperatures of 600 degrees C and implied that was a good reason to doubt the NIST collapse hypothesis. My response was that in addition to the fact that no columns from the collapse initiation area were tested, the NIST collapse hypothesis doesn't really require columns that hot, anyway, so that's a strawman. If you still think your original point has any validity, then I can't stop you from dragging it out again, but I think we've beat it to death for now.
But now the topic now seems to have moved to the general usefulness and applicability of FEA models in the first place. I asked above in a different subthread how any conceivable FEA model could "demonstrate that there weren't other factors"; the point being the general impossibility of logically proving non-existence. I guess I wasn't clear, if you still say this:
> NIST's findings are also consistent with a theory that it was their "middle" model that was the more accurate one and that rather than boost temperatures to make it collapse what they actually needed to do was to factor in additional help (from therm*te or other). This latter explanation is consistent with all their findings so they haven't ruled it out.
That's correct; therm*te was not "ruled out" by the NIST study, but I don't see anybody claiming it was, given the general impossibility of doing that. (Nor, as OTOH pointed out, is that remotely similar to the actual intent of the study.) But my claim is that, unless you can give me some cogent reason to doubt the physical modeling in that analysis or the input parameters used, then the analysis does in fact demonstrate that crash damage and fire alone could have caused the collapses, so there is no need to imagine "other factors" for which you have no evidence. And that IS a significant demonstration if the reason for imagining "other factors" is the claimed impossibility of such collapses without them. No, the analysis does not prove that crash damage and fire alone caused the collapses, nor will any such analysis ever be able to prove that, nor was that the intent, nor is it really necessary.
gyroscope
(1,443 posts)is thermate can indeed be used to cut steel beams. nothing more.
whether or not thermate actually was used on 9/11 is a separate issue.
Natgeo's contention is proven wrong. Their testing methods shown to be a joke.
Regular thermite (weaker than thermate) cutting through an engine block:
------------------------------------------------------------
Thermate used in the military to cut through tank armor:
Because thermate burns at higher temperatures than ordinary thermite,[1] it has useful military applications in cutting through tank armor or other hardened military vehicles or bunkers. As with thermite, thermate's ability to burn without an external supply of oxygen renders it useful for underwater incendiary devices.
http://en.wikipedia.org/wiki/Thermate
William Seger
(11,031 posts)... and given the level of deceit and dishonesty in the rest of the video, I'd need to see independent confirmation of that result before I'd believe it. But even if it's legit, he used fairly small amounts of thermite, but he only did a fairly small amount of damage relative to what it would take to cut through a massive WTC column. Scale his device up to one that could ACTUALLY cut through a WTC column (if that's even possible before his container burned through), and I don't think there's any doubt about how implausible it is that such devices were planted all over occupied office buildings but nobody noticed.
And the point you persist in avoiding: There is not a shred of evidence that thermate charges were used to demolish the building, nor is there any need for any such bizarre theories.
gyroscope
(1,443 posts)if the thermate cut 'only a little way through?'
Apparently, denial ain't just a river in Egypt.
William Seger
(11,031 posts)Big deal. Show me a video of cutting through a vertical column the size of WTC tower columns and then we'll talk about plausibility.
gyroscope
(1,443 posts)that's a pretty serious accusation. do you have any proof?
getting rather desperate are we?
William Seger
(11,031 posts)... raise serious doubts in my mind about his honesty, so I'd need to see independent confirmation of his results. But the real point remains, even if the experiments were legit, he did not demonstrate that he could cut through a WTC column.
gyroscope
(1,443 posts)....if NIST were doing their job, they could probably provide you with such confirmation.
unfortunately, they didn't even bother to look for evidence of explosives and/or incendiaries as they admitted. hence, the citizenry are left to carry out their own independent testing.
because the official report is not credible in the least.
William Seger
(11,031 posts)That is not true. They did not chemically TEST for explosives and/or incendiaries because there was no reason to suspect them. But all of the steel was visually inspected by a team of private-citizen volunteer scientists and engineers at ground zero and at the recycling site, and none of it showed the distinctive characteristics that explosives and incendiaries would have left behind.
The official report is extremely credible to rational people, especially when compared to the implausible scenarios and imaginary evidence offered by irrational "truthers" when they try to reason backwards from a conclusion that they can't substantiate.
gyroscope
(1,443 posts)....absolutely absurd, laughable statement.
Let me ask you this.
What did the terrorists use to attack the WTC back in 1993? That's right. BOMBS.
What did terrorists use to attack and destroy the federal building in Oklahoma City in 1995, with massive loss of American life? That's right genius. EXPLOSIVES/BOMBS.
What did terrorists use to attack the US embassy in Nairobi that took the lives of over 200 people in 1998? EXPLOSIVES.
What did terrorists use to attack the USS Cole that killed more than a dozen American sailors in 2000? Again, EXPLOSIVES.
What do you think the terrorists number one weapon of choice??
But according to NIST, there's 'no reason' to test for the use of BOMBS and EXPLOSIVES after the biggest terrorist attack in US history?
You're right, if your goal is COVER UP a massive crime then there would certainly be no reason to test for explosives. Would there?
OnTheOtherHand
(7,621 posts)I bet you think that "the terrorists" used a car bomb back in 1993. But let me ask you this: did anyone test for the presence of thermite??!!
I could keep going, but maybe you'll take this issue seriously enough to follow through yourself.
gyroscope
(1,443 posts)try again.
OnTheOtherHand
(7,621 posts)gyroscope
(1,443 posts)If they were competent investigators, then they probably would have tested for the presence of thermite or thermate in the 93 WTC car bombing.
as a competent investigator, you want to to test for all types of commonly used explosives and/incendiaries so there's no reason why they shouldn't have tested for the presence of thermite/thermate along with other types of explosive/incendiary materials that could have been used in the 93 bombing.
--------------------------------------
Military uses
Thermite hand grenades and charges are typically used by armed forces in both an anti-materiel role and in the partial destruction of equipment; the latter being common when time is not available for safer or more thorough methods.[30][31] For example, thermite can be used for the emergency destruction of cryptographic equipment when there is a danger that it might be captured by enemy troops. Because standard iron-thermite is difficult to ignite, burns with practically no flame and has a small radius of action, standard thermite is rarely used on its own as an incendiary composition. It is more usually employed with other ingredients added to enhance its incendiary effects. Thermate-TH3 is a mixture of thermite and pyrotechnic additives which have been found to be superior to standard thermite for incendiary purposes.[32] Its composition by weight is generally about 68.7% thermite, 29.0% barium nitrate, 2.0% sulfur, and 0.3% of a binder (such as PBAN).[32] The addition of barium nitrate to thermite increases its thermal effect, produces a larger flame, and significantly reduces the ignition temperature.[32] Although the primary purpose of Thermate-TH3 by the armed forces is as an incendiary anti-materiel weapon, it also has uses in welding together metal components.
A classic military use for thermite is disabling artillery pieces, and it has been used for this purpose during and since World War II; such as at Pointe du Hoc, Normandy.[33] Thermite can permanently disable artillery pieces without the use of explosive charges, and therefore thermite can be used when silence is necessary to an operation. There are several ways to do this. By far the most destructive method is to weld the weapon shut by inserting one or more armed thermite grenades into the breech and then quickly closing it. This makes the weapon impossible to be loaded.[34] An alternative method is to insert an armed thermite grenade down the muzzle of the artillery piece, fouling the barrel and making the weapon very dangerous to fire. Yet another method is to use thermite to weld the traversing and elevation mechanism of the weapon, making it impossible to aim properly.[citation needed]
Thermite was also used in both German and Allied incendiary bombs during World War II.[35][36] Incendiary bombs usually consisted of dozens of thin thermite-filled canisters (bomblets) ignited by a magnesium fuse. Incendiary bombs destroyed entire cities due to the raging fires that resulted from their use.[citation needed] Cities that primarily consisted of wooden buildings were especially susceptible. These incendiary bombs were utilized primarily during nighttime air raids.[citation needed] Bombsights could not be used at night, creating the need to use munitions that could destroy targets without the need for precision placement.
http://en.wikipedia.org/wiki/Thermite#Civilian_uses
OnTheOtherHand
(7,621 posts)So, you don't know what they tested for. Oh-kay. And that's in a case where, as far as I know, everyone agreed that explosives had been used, and where.
I assume that your handwaving insistence that NIST should have tested something for something (or everything for everything) is heartfelt, but it isn't very persuasive.
William Seger
(11,031 posts)... would be to determine what kind had been used. There was no need to determine IF bombs had been used because there never was any doubt about that.
On the other hand, the idea that the WTC towers were brought down by explosives is an insane notion invented on the internet by delusional paranoid conspiracy fans who apparently don't know much about explosives.
Ace Acme
(1,464 posts)by firefighters (Chief Ray Downey and Chief Albert Turi) and by news figures such as Dan Rather, Peter Jennings.
It's quite reasonable when you see a building suffering a total, symmetrical, and near-freefall collapse to suppose that it's not a natural collapse--and NIST made no effort to show that it was a natural collapse. They claim they did not analyze the collapses of the towers.
William Seger
(11,031 posts)Neither Downey nor Turi thought the buildings were brought down by controlled demolitions. It only took me a couple of minutes to find that they both thought that additional bombs might have been planted in the buildings or carried on the planes to kill first responders. And I'm not sure why you're calling Rather and Jennings "experts," but regardless of any off-the-cuff remarks they made that day, neither believes that there was any controlled demolition. If "insane theory" disturbs you, try on "idiotic theory" for size.
Ace Acme
(1,464 posts)I call Downey, Romero, and Hamburger experts. They all thought explosives were involved.
William Seger
(11,031 posts)... to kill first responders, not to bring the buildings down.
After learning more, Romero and Hamburger both changed their minds about initial off-the-cuff statements about controlled demolitions. Do you accept their expertise or not?
Ace Acme
(1,464 posts)Dr. Romero did not change his opinion that a few charges in key places could have brought the towers down.
Mr. Hamburg was made a part of the FEMA investigation. Both can reasonably be suspected of having received
offers they could not refuse.
William Seger
(11,031 posts)As for your claim about Romero:
By John Fleck
Journal Staff Writer
A New Mexico explosives expert says he now believes there were no explosives in the World Trade Center towers, contrary to comments he made the day of the Sept. 11 terrorist attack.
"Certainly the fire is what caused the building to fail," said Van Romero, a vice president at the New Mexico Institute of Mining and Technology.
The day of the attack, Romero told the Journal the towers' collapse, as seen in news videotapes, looked as though it had been triggered by carefully placed explosives.
Subsequent conversations with structural engineers and more detailed looks at the tape have led Romero to a different conclusion.
Romero supports other experts, who have said the intense heat of the jet fuel fires weakened the skyscrapers' steel structural beams to the point that they gave way under the weight of the floors above. That set off a chain reaction, as upper floors pancaked onto lower ones.
Romero said he believes still it is possible that the final collapse of each building was triggered by a sudden pressure pulse caused when the fire reached an electrical transformer or other source of combustion within the building.
But he said he now believes explosives would not have been needed to create the collapse seen in video images.
Conspiracy theorists have seized on Romero's comments as evidence for their argument that someone else, possibly the U.S. government, was behind the attack on the Trade Center.
Romero said he has been bombarded with electronic mail from the conspiracy theorists.
"I'm very upset about that," he said. "I'm not trying to say anything did or didn't happen."
(C) 2001, Albuquerque Journal
> Mr. Hamburg was made a part of the FEMA investigation. Both can reasonably be suspected of having received offers they could not refuse.
One of the really obnoxious and offensive characteristics of conspiracists is their eagerness to slander anyone who won't tell them what they want to hear. But that seems to be the unavoidable result of spiraling delusions that feed on themselves.
Ace Acme
(1,464 posts)He never retracted that statement, and for you to pretend that he did is dishonest.
Chief Downey said he thought there were bombs in WTC2 because the collapse was "too even".
William Seger
(11,031 posts)... but regardless, the more important point would be that we now know much more than Downey did at that time. Specifically we that both towers collapsed after the perimeter columns along one wall slowly bowed inward and then buckled completely inward rather suddenly. That is not behavior that can be explained by bombs, so it should come as no surprise that there is no concurrent high-explosive sound on any of the videos, and no high-explosive signature on any of the seismographs. I believe you are familiar with the appeal to authority fallacy and yet you offer it as an argument. And then this in the same post:
He never retracted that statement, and for you to pretend that he did is dishonest.
Here's what you claimed:
Dr. Romero did not change his opinion that a few charges in key places could have brought the towers down.
... and here's what the newpaper article says:
"Certainly the fire is what caused the building to fail," said Van Romero, a vice president at the New Mexico Institute of Mining and Technology.
So it would appear that you are now claiming that, well, he never retracted his statement that explosives can bring down buildings. And they you try to accuse me or arguing dishonestly? You are a trip, "Ace."
Ace Acme
(1,464 posts)Downey wasn't talking about the behavior of the perimeter columns. He was talking about the behavior of the building as a whole.
As usual, you're shifting the goal posts. The issue was your very simple-minded claim in post 117 that "the idea that the WTC towers were brought down by explosives is an insane notion", which I refuted by citing Romero, Hamburger, and Downey. An argument from authority is only fallacious if it's wrong. My dentist says I need a filling repaired. Is that fallacious because he's an authority, so I should conclude I don't need my filling repaired?
About Romero, he did not change his opinion that a few charges in key places could bring the buildings down. That he changed his opinion that explosives brought the building down does not change the fact that it was not an insane opinion.
William Seger
(11,031 posts)> An argument from authority is only fallacious if it's wrong.
Wrong again. It appears that we need to add "argument from authority" to "circular reasoning" and "straw-man" to the list of logical fallacies that you don't understand. Argument from authority is a fallacy when you argue that someone is correct because he is an authority: X says A; X is an expert; therefore A is true. It's a fallacy because the inference is not logically valid; even experts can be wrong. Just because someone is considered to be an expert doesn't mean that they don't need to base their arguments on reliable facts and valid logical inferences, like anyone else, and if they do that, then citing the soundness of their arguments -- not their expertise -- as reasons for accepting their conclusions is not a fallacy. You should now be able to answer your own question about your dentist's opinion.
Regardless of what the initial reactions were by anyone on 9/11, rational people often change their minds when given more information and time to think things through. Even smart people can sometimes say idiotic things. The notion that the WTC buildings were brought down by controlled demolitions is an idiotic theory, and no citing of a list of people who initially had that speculation on 9/11 changes that. You have refuted nothing.
Ace Acme
(1,464 posts)This is a pattern with you--being very loosey goosey about your specifications and putting a lot of energy
into red herrings.
There's nothing idiotic about the notion that the WTC buildings were brought down by controlled demolitions.
Nobody said Dr. Romero's opinion or Mr. Hamburger's opinions were insane at the time--not even George Bush,
when he demanded no tolerance for "outrageous conspiracy theories" on November 10.
100% of the time before 9/11 when highrise buildings came down it was through controlled demolitions.
Never before 9/11 had a modern highrise building come down from fire.
100% of the time since 9/11 when highrise buildings came down it was through controlled demolitions.
Never since 9/11 has a modern highrise building come down from fire. We've had spectacular high-rise fires
in Grozny, Moscow, Dubai, Shanghai, and Beijing--and none of those buildings fell down.
Controlled demolition was feasible, and there was a strong motivation for it because the terrorizing effect
of the attacks depended on the complete destruction of the buildings.
William Seger
(11,031 posts)... not the least reason being the complete lack of evidence that would unavoidably be present. The idea that steel structures can't, and never have, collapsed due to fire is an idiotic view of both physics and history. The idea that because a high-rise tower has never collapsed completely because of fire before means that it can't happen is an idiotic piece of logic. And the notion that the alleged perps decided on an insanely and pointlessly large, complicated and risky hoax, when something safe and simple would have accomplished the same presumed purpose, because "there was a strong motivation for it because the terrorizing effect of the attacks depended on the complete destruction of the buildings" is a perfectly idiotic "just so" story.
Ace Acme
(1,464 posts)Your claim that there is no evidence is contrary to reality.
The behavior of the buildings is evidence.
I never said a high rise tower can't collapse from fire. I said it never happened before 9/11 and never happened after.
What's complicated about bringing down the towers? FEMA said a few failing truss anchors could do the job. Dr. Romero said a few charges could do it. You claim fires can do it.
Pray tell, what that is safe and simple could have caused the American people to give up their rights without a peep, to become torturers and murderers and occupiers of far-off lands?
William Seger
(11,031 posts)... no high-explosive seismological signature, and no columns and beams cut with explosives in the rubble. Instead, what we get offered as "evidence" by "truthers" is imaginary physics.
With only a handful of perps and far, far less risk of things going wrong or getting caught, the alleged perps could have begun a campaign of car and truck bombings that would have accomplished the same presumed effects that you want to claim. In fact, creating the impression that it wasn't a one-time event would be even more effective. The only part of a "false flag" attack that needs to be a hoax is who gets blamed. The plausibility of the alleged perps instead concocting a controlled demolition hoax and bribing and/or intimidating structural mechanics experts into going along with the cover-up of a mass murder to aid BushCo is simply idiotic. I do believe that one aspect of the "truther" mentality is that most "truthers" never quite made the distinction between Hollywood movies and reality that rational people make when they mature beyond the 5th grade.
Ace Acme
(1,464 posts)How do you know there were no columns and beams cut with explosives?
You just make stuff up and pretend it's a fact.
Car and truck bombings would not have instituted the airport security measures.
There's no need to bribe or intimidate anyone. If you control the people at the top of the investigation (such as Philip Zelikow) then they get to decide what's investigated and what's not, who investigates what, what's plausible and what's not, and which lines of inquiry are unproductive.
Also, as usual, you didn't answer the questions. You make empty assertions, and then when I question you about them, you simply move on to new empty assertions.
What's complicated about bringing down the towers? FEMA said a few failing truss anchors could do the job. Dr. Romero said a few charges could do it. You claim fires can do it.
Pray tell, what that is safe and simple could have caused the American people to give up their rights without a peep, to become torturers and murderers and occupiers of far-off lands?
William Seger
(11,031 posts)By comparing the large number of videos from all around the buildings to videos of actual controlled demolitions. And by the way, it's questions like this that make it impossible to take you seriously.
How do I know there were no seismic events remotely resembling what would be expected if there were controlled demolitions? Because experts who have studied those records say, "There is no scientific basis for the conclusion that explosions brought down the towers."
How do I know there were no columns and beams cut by explosives? Because the FEMA Building Performance Analysis Team, which consisted mostly of private engineers who volunteered to search the rubble for clues to what happened, did not find any such thing, and there should have been LOTS of it if there was a controlled demolition.
> Car and truck bombings would not have instituted the airport security measures.
You still don't understand the nature of your own "just so" stories. You're just assuming that, since that's what happened, it must have been an intentional result of the plot that you also just assume.
> There's no need to bribe or intimidate anyone. If you control the people at the top of the investigation (such as Philip Zelikow) then they get to decide what's investigated and what's not, who investigates what, what's plausible and what's not, and which lines of inquiry are unproductive.
Bullshit, and a good example is the independent engineers mentioned above who were tasked with finding any clues they could about what happened. To explain why they didn't find any evidence whatsoever of your imaginary controlled demolition, you have to include them in your imaginary conspiracy to cover up. The spiraling delusions of conspiracy theories require such spiraling, slanderous but baseless accusations. You just make the conspiracy as big as it needs to be to protect your delusions.
> Also, as usual, you didn't answer the questions.
Which question did I not answer -- the one about, "What's complicated about bringing down the towers?" You're asking what's complicated about rigging two huge, 24x7-occupied office buildings for a top-down type of demolition that's never been done before, and hope nobody notices, nothing goes wrong, and everybody who needs to help you cover it can be coerced into being accessories after the fact of mass murder -- that's your question? Sorry, but I didn't take that as a serious question, either. In fact, it's getting harder and harder to take anything you post seriously. It's all a game to you.
Ace Acme
(1,464 posts)Have you done a study of seismic readings associated with controlled demolitions?
The FEMA BPAT team was excluded from the site except for a "guided tour", as any honest researcher knows. The "independent" ASCE engineers soon found their investigation hijacked by FEMA, so the investigation was no longer independent. Do you get you get your talking points from anonymous propaganda websites?
It is natural to infer motivation from outcomes. Cui bono and all that. Why did the defendant shoot the decedent? Because he wanted him dead.
The behavior of the buildings is evidence of controlled demolitions. Most structural engineers were surprised when the towers came down, because they understand about redundancy and safety factors and all that.
Where do you get the ideas that no clues were found? Dr. Astaneh-Asl found clues. The WPI team found clues. NIST shutting down half their investigation suggests they found clues they did not want to explain.
Yes, what's complicated about rigging three buildings for demolition? Dr. Romero said a few charges could do the job. FEMA said a few failing truss anchors could do the job. NIST said ONE failing girder seat could bring the whole building down.
What makes you think nothing went wrong? Lots of things went wrong--you can see them if you're only willing to look. What that is safe and simple could have caused the American people to give up their rights without a peep, to become torturers and murderers and occupiers of far-off lands?
William Seger
(11,031 posts)> Have you done a study of seismic readings associated with controlled demolitions?
Companies that do controlled demolitions certainly have, mainly for insurance purposes, and according to one such company, Protec:
...
Any detonation of explosives within WTC 7 would likely have been detected by seismographs monitoring ground vibration in the general area. To our knowledge, no such telltale "spike" or vibratory anomaly was recorded by any monitoring instrument.
http://tinyurl.com/z6zyc
At one point, "truther" sites tried to claim that seismic spikes recorded at Columbia University's Lamont-Doherty Earth Observatory in Palisades, New York, proved controlled demolition of the towers, but the University's expert disagreed:
http://www.popularmechanics.com/science/defense/1227842.html?page=5&c=y
> The FEMA BPAT team was excluded from the site except for a "guided tour", as any honest researcher knows. The "independent" ASCE engineers soon found their investigation hijacked by FEMA, so the investigation was no longer independent. Do you get you get your talking points from anonymous propaganda websites?
How ironic and hypocritical, considering that once again you are uncritically parroting bullshit that you read on "truther" sites. Here's what honest researchers know:
http://web.archive.org/web/20041122063735/http://irc.nrc-cnrc.gc.ca/newsletter/v7no1/collapse_e.html
http://www.wpi.edu/News/Transformations/2002Spring/fall.html
http://www.engr.mun.ca/~csce/Page_files/events/upcoming/National_lecture_2003.html
Now your turn, Mr. Honest Researcher: Please point me to a single member of that team who "found their investigation hijacked by FEMA."
> It is natural to infer motivation from outcomes. Cui bono and all that. Why did the defendant shoot the decedent? Because he wanted him dead.
But it is certainly not natural, legal, nor logical to claim that as evidence of anything, since any number of people might have benefited from that shooting. I do hope that "truthers" who think that cui bono is a form of evidence will do society a favor by admitting that when they are called for jury duty, since they are manifestly unfit for the task.
> Where do you get the ideas that no clues were found? Dr. Astaneh-Asl found clues.
Which just goes to show that even after you were soundly trounced in your debate about that with AtheistCrusader, not only did you keep posting the same refuted bullshit over and over and over, here you are trying to get away with shoveling it again. Anyone who still takes you seriously hasn't been paying attention.
> The WPI team found clues. NIST shutting down half their investigation suggests they found clues they did not want to explain.
The first claim is bullshit and the second is just more faulty logic. NIST did not analyze what happened after collapse initiation in the towers because they judged it unnecessary to accomplish their objectives. Regardless of your opinion about that decision, I pointed you to a long list of technical papers by people who are well qualified to do that sort of analysis, but you disingenuously try to score debating points by claiming that since NIST didn't include the analysis of acknowledged experts such as Bazant in their report, such analysis should be ignored. And yet whenever there is anything in the NIST report that interferes with your conspiracy delusions, you just accuse them of dishonesty -- for absolutely no apparent reason other than it interferes with your conspiracy delusions. Anyone who still takes you seriously hasn't been paying attention.
> The behavior of the buildings is evidence of controlled demolitions. Most structural engineers were surprised when the towers came down, because they understand about redundancy and safety factors and all that.
And yet we're still waiting for Gage's "2000 plus architects and engineers" to produce their first technical argument that can withstand expert scrutiny. No, the actual behavior of the buildings is certainly not evidence of controlled demolition, which is precisely why Gage & Co simply ignore anything that doesn't fit, such as the very stuff we're now discussing: no high-explosive sounds, no seismic evidence, and no columns and beams cut with explosives
> Yes, what's complicated about rigging three buildings for demolition? Dr. Romero said a few charges could do the job. FEMA said a few failing truss anchors could do the job. NIST said ONE failing girder seat could bring the whole building down.
I notice that you frequently try to have things both ways. The crux of "truther" claims about controlled demolitions is that it's impossible for complete destruction to follow from local failures as NIST theorizes, so controlled demolition must have been the cause, regardless of how implausible it is that anyone would or could pull off such a thing. If you acknowledge that the buildings could have fallen because of progressive failure, however, then the principle of parsimony says we don't need controlled demolition theories to explain it, so they should not be accepted unless you can provide convincing positive evidence. Instead, we have a very conspicuous lack of evidence that really ought to be there if those theories had any validity.
> What makes you think nothing went wrong? Lots of things went wrong--you can see them if you're only willing to look. What that is safe and simple could have caused the American people to give up their rights without a peep, to become torturers and murderers and occupiers of far-off lands?
If that first claim were true, the perps would have already been executed and "truthers" would no longer be ridiculed as "conspiracy theorists." I already answered your question about safe and simple plots, and yet once again, all you've got is denial.
Ace Acme
(1,464 posts)Three weeks after the event ASCE visited the site and collected data. Does this not suggest that they were excluded from the site for those three weeks, during which time the crime scene was substantially corrupted? The statement says nothing specific about the site visit, and gives far more weight to the collection of data (apparently photographic evidence).
Team members toured what was left of the 16-acre World Trade Center Plaza, interviewed officials and eyewitnesses, and examined remnants of fallen structures at the Staten Island landfill and at salvage yards. Steel samples were cut and cataloged for further study, and some were taken back to WPI for analysis
In contrast to the ASCE tour, WPI actually collected some samples. They found steel that the NYT characterized as partially "Vaporized" and "perhaps the deepest mystery uncovered in the investigation"--a mystery that has never been explained, by the way, but which has shown in empirical studies by Jonathan Cole to be consistent with a sulfidation attack by sulfur-enhanced thermite. Perhaps if ASCE had been permitted better site access, more samples that might have illuminated the mysteries would have been taken, but they were not. As a result, NIST does not have steel samples to support its claim that the fires weakened the towers' structure.
Here is some more information on these issues:
http://www.democraticunderground.com/discuss/duboard.php?az=view_all&address=125x250744
From a House Science Committee Hearing March 6, 2002
http://web.archive.org/web/20021128021952/http://commdocs.house.gov/committees/science/hsy77747.000/hsy77747_0.htm
STATEMENT OF DR. ABOLHASSAN ASTANEH-ASL:
Rep. Crowley:
William Seger
(11,031 posts)... and the small part you did respond to wasn't worth waiting for. I'm ignorant of a great many things but you're not telling me anything I didn't already know about the BAPT investigation. What you're really doing is giving another good example of how conspiracists detract attention from real problems in their relentless pursuit of validating their fantasies.
> Three weeks after the event ASCE visited the site and collected data. Does this not suggest that they were excluded from the site for those three weeks, during which time the crime scene was substantially corrupted?
Who was trying to keep the engineers away from the site so they wouldn't discover the evidence of a controlled demolition? That must have been Rudolph Giuliani. Who decided who would be safe to do the cleanup and haul away all that evidence? That would be NYC's Department of Design and Construction. Who was on the site finding that evidence and having it hauled away to the scrap yard? That would be four separate contracting companies, directed by four FDNY chiefs in four sectors. Now, here's my question to you, for which I don't have an answer: After the completely insane BushCo perps concocted this batshit crazy hoax, who had to go out and get all those people on board with covering up this mass murder? Not a problem for conspiracists; conspiracies are as big as they need to be, and the perps never worry about someone ruining their day by going to the media instead of cooperating, before the plot even gets off the ground, or spilling the beans afterwards.
But then, many dozens of independent investigators did get onsite and in the landfills long before all of the supposed evidence could be destroyed, didn't they. Good thing the perps got to them, too, huh.
You quote-mined Astaneh-Asl's oral statement to the Science Committee, but here is the complete answer to a question in a letter from the Committee that he put in his prepared statement:
I wish I had more time to inspect steel structure and save more pieces before the steel was recycled. However, given the fact that other teams such as NIST, SEAONY and FEMA-BPAT have also done inspection and have collected the perishable data, it seems to me that collectively we may have been able to collect sufficient data. The main impediments to my work were and still are:
1. Not having a copy of the engineering drawings and design and construction documents.
2. Not having copies of the photographs and videotapes that various agencies might have taken during and immediately after the collapse.
Such data has already been made available to ASCE Building Performance Assessment Team. If those are also available to us, we will be able to proceed further with our research. Figure 5 shows an example of analysis of performance of generic steel high-rise structure subjected to the impact of a 747 jetliner and the ensuing fire. The example demonstrates the power of advanced technology developed in aerospace and mechanical engineering that can be brought to bear on this problem. We plan to use the drawings and the data and the software used in the example to build a computer based realistic model of the World Trade Center towers and analyze their response to simulated impact of the 767 planes that crashed into them on 9/11 and the ensuing fire.
Getting to one of the serious questions that conspiracists detract from, Astaneh-Asl and many others were deeply concerned about knowing as much as possible about the collapses in case there were building code changes that might mitigate that sort of disaster in the future. As I'm sure you know by now, Astaneh-Asl is completely hostile to controlled demolition theories -- and in fact, I defy you to find a single investigator who isn't -- and I note that you didn't even attempt to support your disingenuous claim that any of the investigators "found their investigation hijacked by FEMA." However, as a result of testimony by Astaneh-Asl and others at the Science Committee, there is now a law on the books that requires allowing investigators access to disaster sites and all available information such as blueprints. Yes, Crowley was right, conspiracists are having a field day with the way the early days of the cleanup were handled, but that doesn't mean that controlled demolition theories aren't idiotic.
> They found steel that the NYT characterized as partially "Vaporized" and "perhaps the deepest mystery uncovered in the investigation"--a mystery that has never been explained, by the way, but which has shown in empirical studies by Jonathan Cole to be consistent with a sulfidation attack by sulfur-enhanced thermite.
In the first place, you're trying to have it both ways again. Unless you're claiming that the materials scientists were just too fookin' stupid to recognize steel that was melted by thermite, then please explain why it was the "deepest mystery uncovered in the investigation." Seems to me that either it was melted steel or it was a mystery; please make up your mind. As for your claim that it "consistent with a sulfidation attack by sulfur-enhanced thermite", that is unadultered horseshit and you ought to be ashamed of yourself for dumping it on the board again. As you well know by now, the materials scientists were able to determine that it was a eutectic "erosion" that happened a temperature of about 1000 degrees C, so there was absolutely no resemblance whatsoever to steel melted by thermite. After reading through your debate with AtheistCrusader, I have no intention of engaging in dozens of exchanges with you in a futile attempt to get you to acknowledge what "melted" does and doesn't mean, so keep your head in whatever dark, warm place it is on that subject -- just please spare me the bullshit about trying to solve mysteries.
Ace Acme
(1,464 posts)If you really wanted to know, as opposed to posting a rhetorical question, you might investigate the issue for yourself.
Here are some clues.
http://web.archive.org/web/20021128021952/http://commdocs.house.gov/committees/science/hsy77747.000/hsy77747_0.htm
http://www.nytimes.com/2002/03/07/nyregion/ground-zero-building-standards-mismanagement-muddled-collapse-inquiry-house.html?src=pm
The most intense criticism from both Republican and Democratic House members centered on the confusion over just who is overseeing the investigation -- the Federal Emergency Management Agency, the National Institute of Standards and Technology or the American Society of Civil Engineers.
At one point, Representative Anthony D. Weiner, a Democrat from New York City, asked for the official in charge to raise his hand, and two men, and then three appeared to do so. ''We have very serious problems here,'' added Representative John B. Larson, a Connecticut Democrat.
The lack of clear authority has had unfortunate consequences, the House members said. The Giuliani administration started to send World Trade Center steel off to recycling yards before investigators could examine it to determine whether it might hold crucial clues as to why the buildings fell. The full investigative team set up by FEMA was not allowed to enter ground zero to collect other potentially critical evidence in the weeks after the attack, and it did not get a copy of the World Trade Center blueprints until early January, a delay House members found infuriating.
You've shifted the issue from site access and FEMA hijacking ASCE's investigation to the destruction of the steel.
Here's what Fire Engineering Magazine had to say about site access:
You seem to have difficulty imagining Rudy Giuliani cooperating with BushCo. On what basis?
Dr. Astaneh's attitudes are quite clear in his statements to cbs and PBS about the destruction of evidence.
http://www.cbsnews.com/news/culling-through-mangled-steel/
http://www.pbs.org/newshour/bb/science/jan-june07/overpass_05-10.html
Your implicit claim that the problems were only with the early cleanup is off the beam. Fire Engineering Magazine was still screaming bloody murder in January about the ongoing destruction of steel evidence:
Such destruction of evidence shows the astounding ignorance of government officials to the value of a thorough, scientific investigation of the largest fire-induced collapse in world history. . . . Fire Engineering has good reason to believe that the "official investigation" blessed by FEMA and run by the American Society of Civil Engineers is a half-baked farce that may already have been commandeered by political forces whose primary interests, to put it mildly, lie far afield of full disclosure.
http://911research.wtc7.net/cache/wtc/groundzero/fe_burndingquestions.html
The "deepest mystery uncovered in the investigation," as I made clear, is the "vaporized steel" observed by Dr. Astaneh and the WPI researchers. Your ignorance of the fact that sulfur is added to thermite formulations precisely to create the eutectic mixture makes your attitude on the issue indefensible.
Thanks for admitting that you can't dispute that "vaporized" means "melted".
AZCat
(8,345 posts)Lots of us were. Fortunately somebody was listening because the NIST was approved later that year to begin investigating the collapses. It's interesting to read back through the articles as they occurred during the investigations and afterwards, as professionals debated the progress, intermediate conclusions, and then the final recommendations. I cannot, however, find any evidence that Fire Engineering Magazine rejected (or rejects) the main thrust of the NIST report, or that they continued to question the evidence collection that formed the basis of the NIST's work in the same manner as their questioning of the FEMA/ASCE investigation.
Ace Acme
(1,464 posts)As a result, NIST does not have steel samples to support its claim that fire weakened the steel. Ooops!
In fact NIST's core steel samples show that fire did not significantly weaken the steel. It only got to 480 degrees F.
AZCat
(8,345 posts)Rather than proving the steel wasn't weakened by fire, the information available from the recovered steel was insufficient to make a determination either way. Does that suck? Yes, but it's not a crippling flaw for the investigation.
Ace Acme
(1,464 posts)Of course NIST didn't try very hard to find the truth--they used the simplest and cheapest test available.
But we are justified in suspecting that they didn't do more rigorous tests because they didn't want to get more rigorous truth--ansd wanted to leave some wiggle room for propagandists to sow doubt on the internet.
AZCat
(8,345 posts)Please explain what value these suggested tests would add beyond what was provided by the tests that were performed by the NIST or its subcontractors.
Ace Acme
(1,464 posts)and I think I recall a similar tone to NIST's writeup of the paint-crack tests.
AZCat
(8,345 posts)If you can't suggest additional tests and provide justification for them, then your claim "
o)f course NIST didn't try very hard to find the truth--they used the simplest and cheapest test available" is not very well supported.
Ace Acme
(1,464 posts)to detect heat damage to the steel?
You're suggesting that the paint-crack test WAS sufficient to determine reliably that the core steel only got to 480 F?
AZCat
(8,345 posts)rather than just repeat the arguments of others. The paint-crack test wasn't the only one used by the NIST.
Ace Acme
(1,464 posts)AZCat
(8,345 posts)And why does your previous post (#232) only refer to one test, if you knew there were others used? Something doesn't make sense here.
Ace Acme
(1,464 posts)William Seger
(11,031 posts)The collapses in both towers began with perimeter columns buckling inward, and there was evidence found that some perimeter columns reached 600 degrees C, at which point structural steel loses over half its strength. But the theory is that the root cause was "viscoplastic creep" -- a slow deformation of hot steel that is strained -- and that happens at temperatures below 600 degrees. So, the evidence that you say is lacking is not really necessary to support NIST's final theory about what happened, anyway.
Ace Acme
(1,464 posts)The first thing that happened on WTC1 was the antenna dropping 18 feet. How does that square with a collapse beginning at the perimeter?
William Seger
(11,031 posts)I also can't explain why the south tower leapt 18 feet in the air and did a pirouette before falling.
But then, I don't need to explain things that didn't happen. Prove to me that the antenna dropped 18 feet before the perimeter wall buckled, but I'm going to insist that you use videos shot from the east or west to do it (for reasons that anyone familiar with the claim will already know).
Ace Acme
(1,464 posts)The videos shot from the e and w are too far away to show that. The antenna was 350 feet tall.
William Seger
(11,031 posts)Fail.
Ace Acme
(1,464 posts)It's not.
William Seger
(11,031 posts)http://fire.nist.gov/bfrlpubs/build05/PDF/b05040.pdf
Edit to add a gif I did several years ago (since you will no doubt accuse me of blindly accepting NIST's report):
Ace Acme
(1,464 posts)if the antenna did or did not drop before your gif begins.
Also, not the EXTREMELY WEASELY LANGUAGE of NIST's statement. They did not deny that the antenna sank. They simply reported another and not at all contradictory fact, and allowed the reader to infer that this fact meant that the antenna did not sink. They did not say that.
It's like saying "Some have said I subscribe to the Weekly Standard. I subscribe to Atlantic and Harper's."
William Seger
(11,031 posts)... and you're just repeating yourself.
Maybe later we can go around the barn a few more times about the other stuff, but let me ask you again to make up your mind: Was the steel melted by thermite, or is it the "deepest mystery uncovered in the investigation?" Are you seriously saying that the qualified materials scientists who examined that piece of steel are too stupid and ignorant to recognize thermite melting? And if those scientists are correct that the "erosion" happened at 1000 degrees C, and there is no slag present, on what grounds do you claim that Cole found anything remotely resembling thermite melting? Can you respond to these questions or not?
> Thanks for admitting that you can't dispute that "vaporized" means "melted".
Yes I can, and I will right after you respond to the questions above. Your games are getting tiresome.
Ace Acme
(1,464 posts)Not anonymous know-it-alls speculating.
If you had bothered to watch Mr. Cole's video, you would know that he created a thermite charge that exactly recapitulates the thinning and holes in the WPI samples.
AZCat
(8,345 posts)says we should all listen to his opinion that we need new investigations. Yeah, that's not hypocritical.
Ace Acme
(1,464 posts)My opinions are opinions. My facts are facts. You expect your unsubstantiated opinions to be taken as fact.
AZCat
(8,345 posts)Again, you're an anonymous poster on the internet. The same type of person about who you said "Who cares what an anonymous internet poster thinks?"
Ace Acme
(1,464 posts)... nature of the government investigations, and to conclude that new investigations are needed.
I'm not foolish enough to expect anything from you.
AZCat
(8,345 posts)very few have concluded that new investigations are needed. This may be in part because people like you continually fail to prove this "demonstrably incomplete and corrupt" claim.
Ace Acme
(1,464 posts)the need for new investigations.
AZCat
(8,345 posts)What kind of job would have that kind of dependency? If anything, new investigations would create more work, right?
Ace Acme
(1,464 posts)IOW, most professional jobs.
AZCat
(8,345 posts)I'm guessing you've never worked as a professional, if that's how you perceive professional jobs. I think this is yet another reason you should probably stick to discussing topics where you have some competency, because otherwise you just look foolish.
Ace Acme
(1,464 posts)Yes, I've worked in professional jobs, and among my peers that the ethic is clearly
"I'm making so much money I don't want to mess up a good thing in any way."
William Seger
(11,031 posts)So you're saying that it's only a "deep mystery" to the materials scientists because they're too dumb to recognize thermite melting, and that you can tell just by looking at a video that Cole "exactly recapitulates the thinning and holes in the WPI samples." That's, um, interesting that an anonymous internet poster thinks that... but, hey, who cares.
Ace Acme
(1,464 posts)It's crude, and it makes you look foolish.
William Seger
(11,031 posts)It was thermite melting AND a "deep mystery" to materials scientists?
Ace Acme
(1,464 posts)William Seger
(11,031 posts)You won't actually SAY that it was thermite melting because that piece of steel doesn't actually support that conclusion, and since it's implausible that materials scientists wouldn't recognize thermite melting, you don't want to get stuck having to defend such an outlandish claim. You're just blowing smoke; it's all a game to you. Unfortunately, you're not very good at it.
Ace Acme
(1,464 posts)Did it never occur to you that maybe they did recognize thermite melting, but were not willing to say so?
They said it was as sulfidation attack resulting in intergranular melting. That is consistent with a thermite attack as demonstrated by Mr. Cole.
William Seger
(11,031 posts)Yes, it occurred to me, but then it immediately occurred to me that that is highly implausible, and it's highly implausible that no other ambitious materials scientist would step up to point out that they see signs of melting, which is not surprising since I certainly can't see any, either. While it's true that implausibility doesn't mean it didn't happen, you insist on ignoring that such high implausibility makes the claim extraordinary, and that we simply don't need any such extraordinary claims to explain why the building fell, and that extraordinary claims require extraordinary proof. This "proof by assertion" doesn't do the trick:
> That is consistent with a thermite attack as demonstrated by Mr. Cole.
Prove it, since Cole certainly didn't do anything but demonstrate a superficial resemblance, and that's only if you blithely ignore the slag that his thermite melting produced, and then ignore that he didn't get that result using the apparatus that he imagines cut the columns, and then don't worry too much that nobody else has duplicated his results.
Ace Acme
(1,464 posts)The report said the samples suffered intergranular melting because of a high temperature sulfidation attack.
By mixing sulfur with thermite, Mr. Cole did a sulfidation attack producing results identical to those in the report's samples.
Dr. Barnett did not object to the statement attributed to him by the New York Times:
http://www.nytimes.com/2001/11/29/nyregion/29TOWE.html?pagewanted=2
The WPI scientists' own House Organ wrote up their work as "The Deep Mystery of Melted Steel" and that title remains on it to this day. http://www.wpi.edu/News/Transformations/2002Spring/steel.html
There was melted steel. You're denying reality.
William Seger
(11,031 posts)... materials scientists would not be "mystified" by thermate melting; and you have yet to prove that Cole produced "results identical to those in the report's samples." You invent your own reality.
Ace Acme
(1,464 posts)The report says"Heating of the steel into a hot corrosive environment approaching 1,000 °C (1,800 °F) results in the formation of a eutectic mixture of iron, oxygen, and sulfur that liquefied the steel."
Last time I checked, "liquified" steel was melted--except on Planet Seger.
William Seger
(11,031 posts)The quote you preferred is imprecise, and while the imprecision would ordinarily be insignificant, in this case it matters: It was the eutectic mixture that liquefied, and the important point is that the mixture liquefied at 1000 degrees C, well below the melting point of steel and well below the temperature of thermate. The distinction matters because 1000 degrees C is within the range expected in the fire, and it matters because you were asked to substantiate your claim that, "By mixing sulfur with thermite, Mr. Cole did a sulfidation attack producing results identical to those in the report's samples." It appears that you cannot do that, so you try to dodge the real issue with word games. Fail.
Ace Acme
(1,464 posts)At best you are showing your desperation in pedantically seeking to distinguish between "melting" and "evaporation" and "liquefaction"--as if there were any practical difference when we are talking about evidence that has not been properly investigated and that needs complete and thorough investigations.
William Seger
(11,031 posts)There's nothing pedantic about distinguishing that the eutectic mixture could melt at 1000 degrees C whereas steel cannot, because that temperature is in the range expected in the fire. You deliberately seek to confuse the issue so you can disingenuously insinuate that if "steel" was "melted" then thermate is the only plausible explanation. Fail.
Ace Acme
(1,464 posts)Thermate is the only practical explanation that has been proposed and demonstrated.
Gypsum doesn't attack the steel. Jonathan Cole tested that.
If you want to suggest that carpets or mousepads can attack the steel in a 1000 C fire, you're welcome to try to demonstrate it. NIST made no effort to do so.
William Seger
(11,031 posts)I'll keep repeating that as many times as you care to deliberately misrepresent it. And yes, we've already established WHY you want to misrepresent it, but no, you have not demonstrated that thermate is a "practical explanation" -- still waiting for that -- and you have not given any reason for assuming that if the sulfur wasn't from gypsum then it must have been from thermate. It would appear that all you have is a pocketful of empy assertions.
Ace Acme
(1,464 posts)http://911research.wtc7.net/wtc/evidence/metallurgy/WTC_apndxC.htm
William Seger
(11,031 posts)A36 structural steel melts at no less than 1,426 degrees C, regardless of the heat source. When steel becomes infused with sulfur at high temperatures, however, then that eutectic mixture can melt at around 1000 degrees C. And again, the point that you insist on dodging is this: If the eutectic erosion happened at 1000 degrees C, then we don't need thermate to explain it. You try to dodge that critical issue by focusing on the word "melted" while ignoring WHAT melted.
Wanna go another round? Suit yourself.
Ace Acme
(1,464 posts)Last edited Mon Dec 23, 2013, 12:41 PM - Edit history (1)
and how come NIST's core steel samples only show heating to 250 C.
William Seger
(11,031 posts)There are any number of possible sources of the sulfur, and since Cole only ran his experiment with a single setup and only for a 24-hour fire, he hasn't really ruled out any of them. If you want to believe thermate is the most plausible explanation unless someone can find the exact source of the sulfur and the exact conditions that produced the "eutectic corrosion," then suit yourself. But if that's best reason you can give for why thermite is the most plausible explanation, then pointing out that your logic is flawed is sufficient. As of yet, you haven't even demonstrated that thermate can duplicate the effect, and since thermate produces slag, I seriously doubt that you ever will. The device that Cole (allegedly) cut the small beams with didn't produce that result: His cuts looked (suspiciously?) like torch cuts, which investigators would not likely have missed in the debris if enough columns had been cut to bring down the buildings. Which also brings up the point that if the "eutectic corrosion" was the cause of the collapses, then it should have been found all over the place in the debris, not just those two samples.
> and how come NIST's core steel samples only show heating to 250 C
(A) That's explained in the report (limited samples); and (B) it's not really relevant to the NIST theory, which is viscoplastic creep of the floor joists and buckling of the perimeter columns.
Ace Acme
(1,464 posts)That's why it's used for fireproofing.
If there are "any number of possible sources of the sulfur," how about you list them?
Mousepads? Carpet? What've you got? The WPI guys said the source of the sulfur is a mystery. Maybe you could clue them in.
I didn't say that thermate was the most plausible explanation. I said it was "the only practical explanation that has been proposed and demonstrated." You have a tendency to rewrite reality to fit your ideological needs.
Thermate didn't produce slag in Mr. Cole's blasts that reproduced the thinning and the holes. The steel was vaporized in those.
The steel was scooped up from Ground Zero so carelessly that the complete body of a man in a business suit turned up in the landfill. So don't tell me what "investigators" would have missed or what samples "should have been found all over the place." Apparently NIST couldn't find any core steel that had been weakened sufficiently to cause it to fail.
You seem to be on a mission to defend NIST. Why? What would be so awful about having new investigations? Why do you labor so mightily to deny that they are needed? What are you afraid of?
William Seger
(11,031 posts)You could at least investigoogle, and the first hit for "wtc sulfur" is this: http://www.911myths.com/Sulfur.pdf
Greening is no fan of NIST, btw -- he coined the amusing term "NISTians" to describe people who blindly support their report.
> I didn't say that thermate was the most plausible explanation. I said it was "the only practical explanation that has been proposed and demonstrated." You have a tendency to rewrite reality to fit your ideological needs.
Say what? You say it's the "only practical explanation" but you don't consider it to be the "most plausible?" That's positively weird, unless one considers that your primary aim since you started posting here seems to be playing word games. But I see you threw in "demonstrated," which I am still waiting for.
> Thermate didn't produce slag in Mr. Cole's blasts that reproduced the thinning and the holes. The steel was vaporized in those.
Um... bullshit. You are the one who appears to be fond of making empty assertions. The maximum temperature of thermitic reaction is right around the boiling point of steel, so some small amount may have been vaporized, but claiming that no slag was produced is bullshit, since even in that unclear video, slag can be seen (which is precisely why it doesn't look all that much like the WTC samples). Backed into a corner, you are talking through your hat.
> Apparently NIST couldn't find any core steel that had been weakened sufficiently to cause it to fail.
Well, gee, maybe that's one of the reasons why their theory doesn't hypothesis that a weakened core was the initial cause?
> You seem to be on a mission to defend NIST. Why?
Wrong again. There are qualified people such as Dr. Greening who have made criticisms of the NIST report which seem to me, a layman, technically valid, and I would be foolish to try to defend NIST against those criticisms. As much as you would like to flatter yourself by inclusion on that list, my "mission" here is to challenge people who seem to me to be serving up agenda-driven bullshit instead of valid criticism to prove their claims. If I'm the one who is wrong and you can make a valid argument, I give you every opportunity to prove it. I do that because I believe that bullshit doesn't do anyone any good and that the truth actually matters. To me, the proof that the "truth movement" is a pack of hypocrites is that they are completely baffled by that attitude.
But it isn't just your vacuous assertions and disingenuous claims; you then go on to try to bolster your absurdly weak case by slandering NIST as being dishonest and accessories to covering up a mass murder. And you don't stop there; your spiraling delusions cause you to just keep expanding the targets of your slime to include anyone who doesn't tell you what you want to hear. To me, that is a behavior pattern that is well worth opposing.
> What would be so awful about having new investigations? Why do you labor so mightily to deny that they are needed? What are you afraid of?
Wrong again; if nothing else (and I seriously doubt there would be anything else), I do believe it will be rather amusing to have bullshit peddlers like Richard Gage and Steven Jones exposed to some sunlight. The "truth movement" should be careful what they wish for, and I'll take very short odds on the outcome of having their bullshit exposed to objective analysis by people who actually know what they are talking about.
William Seger
(11,031 posts)... or quit wasting bandwidth, please.
Ace Acme
(1,464 posts)They said it was as sulfidation attack resulting in intergranular melting.
The thinning of the steel occurred by a high-temperture corrosion due to a combination of oxidation and sulfidation.
Heating of the steel into a hot corrosive environment approaching 1,000 °C (1,800 °F) results in the formation of a eutectic mixture of iron, oxygen, and sulfur that liquefied the steel.
The sulfidation attack of steel grain boundaries accelerated the corrosion and erosion of the steel.
William Seger
(11,031 posts)I'm asking you to prove (1) that the materials scientists recognized thermite melting but didn't report it; and/or (2) that Cole duplicated the eutectic erosion with thermate.
Try again.
Ace Acme
(1,464 posts)William Seger
(11,031 posts)Ace Acme
(1,464 posts)Mr. Cole subjected steel to a high-temperature sulfidation attack and recapitulated the appearance of the WPI samples.
You provide no evidence that the materials scientists didn't recognize thermite melting. In fact their wild hypothesis about acid rain suggests they were quite consciously dancing around the issue of where the sulfur came from--which by the way was never explained except through the thermate hypothesis.
William Seger
(11,031 posts)... for you to provide any reason to believe that Cole "recapitulated" anything more than the superficial "appearance of the WPI samples," or actually how he did even that much since all you provided was a video that doesn't even give a clear look at that, or how he did whatever he did with the same devices he (allegedly) cut steel beams with.
> You provide no evidence that the materials scientists didn't recognize thermite melting.
Say what? The evidence is their report itself, which clearly says that the eutectic erosion -- not melting -- happened at a temperature around 1000 degrees C. If you want to claim that they DID recognize thermite melting but then lied in their report to help BushCo cover up a mass murder, nobody is required to disprove your extraordinary claims.
Ace Acme
(1,464 posts)With the WPI report you make a great inference from what they didn't say, mischaracterize what they did say, and leap from that to a whopper of a straw man argument.
Thanks for being so self-revelatory.
William Seger
(11,031 posts)Thanks for being so self-revelatory.
Ace Acme
(1,464 posts)William Seger
(11,031 posts)... you can't even prove that it really looks the same, much less that it shows a similar eutectic corrosion. The fact that you're so easily convinced that Cole duplicated the effect is not sufficient.
Ace Acme
(1,464 posts)William Seger
(11,031 posts)Ace Acme
(1,464 posts)... sulfidation attack on the steel, even though you provide no reason to believe that at all.
You don't even provide any theoretical basis for that opinion, let alone demonstrate it. You only make empty claims.
Why are you so afraid of new investigations? What would be wrong with bringing current knowledge and computer power to the problems?
wildbilln864
(13,382 posts)Again!
"and none of it showed the distinctive characteristics that explosives and incendiaries would have left behind. "
What do you think those distinctive characteristics would be?
Response to wildbilln864 (Original post)
gyroscope This message was self-deleted by its author.
BlueStreak
(8,377 posts)This seems like a very round-about and unreliable way to bring down the buildings.
I have been deeply troubled by WTC7 because that is the one piece that seems to be completely impossible under the government's theory of events. The fact that we are given such lame explanations for WTC7 makes me suspect everything.
However, I really don't get the demolition theory either. The jets did in fact crash into the building. I guess we can't say for certain that this was Osama acting independent of the US Government. But if there was a demolition of the buildings, then the parties in charge of that had to be deeply involved in the plan to hijack the airliners.
And that all seems like a terribly complex way to do this. If they were prepared to demolish the buildings and blame it on terrorism, why not just do that and say that terrorists invaded the building and planted bombs? Why go to all the trouble to do the hijacking, considering there were so many things that could go wrong with that plan?
Ace Acme
(1,464 posts)The "toxic tenant" theory was proposed by a Swiss professor of engineering some years ago, Dr. Hugo Bachmann. Someone could have rented offices, moved in explosives hidden in buckets of paint and copy machines, and sneaked out at night to work in the elevator shafts. If this is what happened, it would be highly embarrassing to a security company owned by friends of the Bushes--so it's no surprise that the very notion would be unthinkable to the authorities.
The reason to use the airplanes is because they were far more effective as a means of terrorism than bombs alone. People all over the country see airplanes every day and remember 9/11. People don't see men moving suspicious-looking packages into buildings every day.
Also, connecting the incident to airliners permitted the Homeland Theater of airport searches, gropings, naked scannings as a constant reminder and to desensitize people and make them complicit in the loss of liberties. How many millions of people made their peace with obtrusive searches saying, "yeah, it's a pain in the ass, but when I get on the plane I'm glad they're doing it"?
BlueStreak
(8,377 posts)Last edited Wed Dec 11, 2013, 08:52 PM - Edit history (1)
I mean, these were the guys who couldn't shoot straight. They were hardly a well oiled machine. Given how they stumbled through the preparations, it is really amazing they were able to fly the planes at all. This is not the profile of the kind of enemy we see with al Qaeda.
The careful planning and flawless execution that would have been required to rig up the explosives in those buildings is so far beyond what we saw of any of Osama's people that it makes no sense at all. And that leaves gaping holes.
Let's say I work for Osama. We're already going to fly two planes into the towers. And now we're going to work for months setting up thousands of charges in the towers -- all under some central control. Why would we do this? After all, aren't the plane crashes enough terror? Why even bother? The amount of extra terror you get from imploding the buildings hardly seems worth the effort.
But OK, let's say you want to bring one of the towers down just for that added bit of terror. Are you going to take the risk and all the extra work to do both towers? I just can't see that.
And if all of the above is true, that doesn't explain why you would then go rig up WTC7 for a similar implosion. That's not terror. That's just strange at that point.
I'm not feeling it. *IF* the buildings were imploded, it was done by somebody who had a lot more skills, resources, and protection than Osama bin Laden, and a whole lot more good reason to take out all of those buildings, especially WTC7.
Ace Acme
(1,464 posts)Last edited Wed Dec 11, 2013, 09:38 PM - Edit history (1)
(Sorry about the snide title. You didn't deserve that. The prevailing manners in this group make me forget mine.)
I try to avoid having conclusive opinions and instead stick to established facts (and speculations clearly identified as such).
I am not advocating the "toxic tenant" theory. I simply pointed out that it exists, and commented on some of the implications if it were true.
Seems to me the part of the plot that is attributed to al Qaeda went about perfectly. They evaded detection even though the presence of two of their number was known to both the FBI and the CIA and even though their alleged ringleader and another alleged pilot had been named in a warning from the Mossad. They evaded interception by NORAD even while going off course hundreds of miles from their targets and bumbling around for a total of over 100 minutes. (The only plot I would expect to succeed would be one where the planes were hijacked immediately after takeoff and immediately flown into the targets.) They managed to hit their targets dead on in the three shots they got. And with just two airplanes they brought down three buildings! That's pretty damn flawless.
No, plane crashes are not enough terror. People are used to plane crashes. A few hundred people die. It happens. To turn a bunch of little guys with boxcutters into existential threats to western civilization, the towers had to fall.
You may be right that rigging the towers was too much of a job for Osama et. al. But don't forget, we're expected to think that fires did the job. If fires can do it, why not the best talent Osama could hire? And how do we know Osama did it? Seems to me the Russians would be pretty highly motivated, anxious to lure us into a bankrupting 10-year-war in Afghanistan.
zappaman
(20,612 posts)You win for funniest post on the internet today!
Congratulations!
You will also automatically be nominated for best of the week and I like your chances!
Ace Acme
(1,464 posts)BlueStreak
(8,377 posts)You are arguing that the plane hijackings and crashes are unlikely because they depend on a lot of people in government not being very diligent.
Well ...
Well ...
I just don't find that surprising in the least.
People were able to get box cutters past security? Not exactly news.
They were able to overpower flight attendants? No story there.
They killed pilots? Gruesome, but not very surprising.
They steered 3 or 4 planes into their targets on a day when visibility was good? Takes some skill, but if I don't have to learn how to take off or land, I think I could manage to steer a plane with a little practice.
The military couldn't sort all this out, get planes aloft, and shoot the hijacked craft out of the sky? Well, we didn't take out many of the attackers at Pearl Harbor either. The element of surprise is a big advantage.
I agree the WTC7 collapse/implosion is most bewildering, and the government theory is nowhere near adequate.
But the problem we have is that if you back up from WTC7 and say that proves there was a planned demolition, that means that the two big towers had to be planned demolitions also. That, in turn, means that there had to be some team in that building that had the expertise, access, time, and opportunity to plant thousands of charges in order to do what is claimed in these video analyses.
I'm sorry. None of Osama's people could have done that in 1000 years. So the only way that version of things works is if you believe either a rogue element of the government -- perhaps using somebody like Blackwater, did such an operation. Or alternatively, all those financial interests that would profit from the towers crashing and the SEC records being destroyed employed a company like Blackwater to do it.
But we know that the planes crashed into the building. And if you believe that Osama was behind THAT part of it, then you have to believe that the demolition team (either the government or Wall Street money) was teamed up with Osama, each seeing their common interest in this operation.
In other words, the video argument doesn't stand on its own. To accept the video argument, then you must accept that this was a plot that goes way beyond Osama bin Laden. I'm not saying that is impossible. Our government has done some pretty damned evil things throughout its history. This would top them all by a wide margin.
Ace Acme
(1,464 posts)It's a question of the security apparatus ignoring warnings from 13 foreign countries, 4 FBI offices, and the CIA.
The FBI had a memo entitled "Kamikaze Pilots".
The Mossad warned of 19 terrorists inside the USA planning something big, and they named names. We don't know how many names, but the 4 that have been released include 2 alleged 9/11 pilots and 2 alleged 9/11 hijackers who were known by both the FBI and the CIA to be al Qaeda agents and who, according to Bob Woodward, bought 10 airline tickets under their own real names dated 9/11/01.
The military is not expected to shoot airliners out of the sky. It is expected to fulfill its normal mission of intercepting off-course aircraft, establishing communication with them, and ordering them to land. A GAO report shows that in the early '90s this mission was routine, an everyday matter for fighter scrambles.
According to FEMA, a few failed truss anchors started a chain reaction in the towers that brought the buildings down. This was conventional engineering wisdom for 3 years. According to a demolitions expert, Dr. Van Romero, a few charges in key places could have brought the buildings down.
BlueStreak
(8,377 posts)FBI ignoring warnings? Happens all the time. How many pieces of information do they receive in a day.
The video commentary that this thread is about talks EXPLICITLY about lots and lots of charges. The speaker calls attention to all those puffs of smoke and argues this means there were explosions on practically every floor. Hr points out many things he considers evidence of explosive charges.
You can't have it both ways. You can't cite a hysterical video that talks about hundreds if not thousands of charges, and then turn around and say,"but really it would have been easy because they really only had to take out a couple of bolts in key places."
Which is it? Is it the video version or is it the magic bolt version? In either case, this is not how al Qaeda ever worked. They drove a van full of explosives into the basement garage. That is their speed. They have never, ever done an operation that required the kind of skills you are implying here.
If the towers were brought down by explosives, Osama bin Laden had nothing to do with that.
Ace Acme
(1,464 posts)Governments can be competent when they want to--invading Normandy and subverting governments and building bridges and putting a man on the moon. Governments can also be incompetent when they want to--when it serves the ideology of the neocons, for instance.
The video does not talk about hundreds or thousands of charges. It points out the presence of "squibs" many floors underneath the active collapse zone. It does not theorize. It invites the observer to observe.
I don't pretend to know if al Qaeda did 9/11 or not.
intaglio
(8,170 posts)how the F~<K do you stop it going off early?
How, if the charges survive the fire, do you stop the impact and fire from destroying the control wiring and circuitry?
How do you control an aircraft not designed for remote flight so accurately that it hits the precise floor you need to make sure the cover story is possible?
Do not say "well they could be landed remotely" because flying in close proximity to high buildings is nor like an approach to a landing field and the accuracy and response times of the of system available at the time were nor good enough.
Other questions like "how were the charges installed?" and "why use thermite when there are better and less detectable methods?" of course never enter the heads of the conspiracy buffs.
Ace Acme
(1,464 posts)Also, thermite encased in cartridges could be fireproofed.
Radio control would obviate wiring complications, and would allow reprogramming of the ignition/detonation sequence if necessary.
Airliners operate on an autopilot tracking beam to guide them into the runway. I was told by a retired airline pilot that the precision of this autopilot was +/- ten feet. A radio beacon placed in the tower could guide the airliner into the target.
Aidan Monaghan claims that by 1994, remote controlled 737s were making landings with accuracy within a few centimeters.
I'd certainly be curious about the "less detectable methods" you propose that are better than thermite.
How are charges installed? Well, of course that depends on where they are, and who installs them. Most of the main structural columns were accessible for most of their length from the towers' 15 miles of elevator shafts. Some people have proposed that explosive mixtures could have been sprayed inside the hollow box columns through a small hole in the column wall.
intaglio
(8,170 posts)You can ignite thermite using a glycerol oxydation reaction, you can ignite thermite using a propane torch it just takes longer.
Radio control does NOT obviate wiring problems, it makes the problems worse. You cannot control the radio environment around your charge especially next to a fire because flames are ionized gases so controlled, timed ignition would be impossible.
If radio control made life easier then every demolition company on earth would be using it, they don't because it is unreliable. Many are unhappy about using electrical connections because they are seen as unreliable especially as explosives (including thermite) produce a detectable EMP.
+ or minus 10 feet is a 20 ft margin of error 10 ft is approximately equal to 1 floor. These error rates are under landing field conditions where there is a guide beam; not after completing a steep bank on approach to a tall building in an environment of tall buildings.
Thermite is very detectable because it burns at such a high temperature that the burnt ends look like wax - the metal flows and drips. None of the recovered building debris had such a signature. Yes, there was molten metal seen but it is far more likely that it was depleted uranium ballast from the aircraft.
Less detectable - a shaped charge at non ideal distance, the cut would not be clean and would resemble a heat induced fracture especially if the shaped charge were not of a regular shape.
I know that conspiracy cultists make up their own reality and will spend hours finding exceptions to every rule and ignoring the glaring holes in their arguments, such as that although the beams might have been accessible from the shafts it ignores the complete impracticality of moving large quantities of explosives, detonators, wiring (or fantasy radio dets) assembling them, performing safety checks, continuity checks, circuit checks, leaving them for an unspecified length of time risking detection and accidental premature detonation.
Ace Acme
(1,464 posts)Demolition companies are not going to use radio control because the detonators are too expensive. Their expense does not make them fantasies. Radio detonators (in the form of cell phones) are used in Afghanistan for IEDs almost every day.
Thermite can be formulated to produce many different effects. One effects described in the rubble is steel that is partially "vaporized" or "evaporated". Another effect described in the rubble is "melting of girders" and "molten steel running down the channel rails" and "like a little river of molten steel".
I've never seen any evidence that depleted uranium was used for ballast in 767s.
What makes you think "large quantities of explosives" would be needed? According to FEMA a very few truss anchors failed, and that initiated a chain reaction bringing the entire building down. That was conventional engineering wisdom for 3 years! Dr. Van Romero opined that a few charges in key place could have brought the buildings down.
intaglio
(8,170 posts)So say the aircraft crashed one floor lower how would that not be an obvious demo? Say the aircraft crashed one floor higher how would that not disrupt the demo charges?
Fantasy and special pleading.
Oh and that figure for auto-altitude control to within a couple of centimeters? Better tell the US Navy they are 12 years behind the times because they have only just managed to successfully land a drone on a ship.
Ace Acme
(1,464 posts)... or even in real time under joystick control as the building comes down. These control technologies were developed back in the 80s when MIDI technology allowed a single musician to control a stage full of synthesizers from a single keyboard. Later the CAN network was developed allowing a whole bunch of computer chips in an automobile to communicate with its related systems. It needs only conversion to wireless communication.
If the airplane crashed one floor lower, I don't see what difference it would make.
It's undisputed that a 727 was landed 6 times by remote control in 2001.
http://www.spiegel.de/wissenschaft/mensch/sicherheitssystem-entfuehrte-maschinen-landen-selbstaendig-a-164845.html
http://usatoday30.usatoday.com/tech/techreviews/2001/10/2/remote-pilot.htm
Note the USAToday says: "Military and civilian jets have been landing on autopilot for years, but the Raytheon test used technology that provides the extremely precise navigational instructions that would be required for remote control from a secure location."
intaglio
(8,170 posts)Why, if radio dets are so wonderful, does the demolition industry completely eschew them?
What happens to the wires of a wired system in a very hostile environment like a building where a plane has crashed and is burning?
How do you avoid premature detonation of your charge in a hostile environment like the twin towers?
How the f'n hell do you time the burn rates of these fantasy thermite charges so that the building comes down as planned? Thermite burns 5 or 6 orders of magnitude too slowly to allow such control.
If thermite could be used for demolishing steel buildings the demo industry would use it because of the lack of pressure wave and associated lack of ejecta. The demo industry does not use thermite.
How do you control altitude and attitude of the aircraft so that it strides the precise floor you need it to strike? Remember the 2nd aircraft banked steeply before it's approach.
Ace Acme
(1,464 posts)You also use complex serial codes and handshaking protocols.
I told you why the demolition industry eschews radio controls--because they're expensive. Also, it's very likely that their insurers are using very conservative spec books that were written 30 years ago.
I've already answered these questions.
There's no need for a wired system when the charges are under wireless control.
Who cares if there's a premature detonation or two? On a fire floor there aren't going to be any witnesses.
Why do you think fire is going to cause premature detonation or ignition? Many explosives are immune to fire, and fireproof packaging could be devised for both thermite and explosive charges. Also, explosive or thermitic materials sprayed INSIDE the hollow core columns would be protected from fire.
You time the burn rates of precision thermitic charges by empirical experimentation. They're not "fantasy". Jonathan Cole has built such charges. With two pounds of thermite he can cut a substantial girder making vertical cuts.
The demo industry is highly motivated to maintain the barrier to entry in the industry. Thus they would prefer to use explosives and restrict the club to those licensed to use them.
Altitude in aircraft is controlled through use of the elevator planes, I believe. Attitude is complex and depends on elevators, rudder, wing flaps, and other factors.
intaglio
(8,170 posts)Insensitive receivers in a noisy environment and powerful transmitters. How do you stop these ridiculous fantasy devices from interfering with all the other electronic equipment in the area?. How in an environment that is generating, essentially, a constant stream of random numbers do you ensure that your encrypted transmission remains uncorrupted?
Too expensive for use by demo contractors - your having a laugh aren't you? Are you really saying that 10,000 plus feet of det cord is cheaper than 100 simple microprocessor based radio receivers? Are you saying that instead of a total loss system based on physical connectors and timing based on length of det cord run is cheaper in either materials or man hours than a 1 fix per charge electronic system. Are you actually telling me that if a wired electronic system where the cable runs have to be measured and resistances calculated together with man hours installation and checking are cheaper than a disposable microprocessor based dets? I suggest, very strongly, that one day you take a walk in the real world.
You have answered the other difficulties I raised? in what world?
You falsely claimed that thermite is difficult to set off, I pointed out that long term exposure to heat such as the glycol oxidation reaction or a propane torch can set off thermite; you ignored that.
You have claimed (falsely) that the altitude of aircraft could be so closely controlled that there would be no danger of the aircraft striking too high or too low. I pointed out that altitude can only be controlled that closely in proximity to an airport with a guidance beam; to which I will add that the airport has to have Doppler radar. I also pointed out that it is nearly impossible to accurately control the height of an aircraft after a steep bank.
You have not answered my point about the extended burn time of thermite making accurate control of the demolition process impossible.
You have not answered my point about how, if thermite is good for demolishing steel structures, it is NEVER used by the demolition industry despite the advantages of reducing debris and acoustic shock.
Essentially your entire confection depends upon a series of impossibilities and non-existent technologies
Ace Acme
(1,464 posts)if the signal was clean (free of harmonics), if the signals were pulsed, and if the transmitters were located inside the towers.
You are inventing impediments. You may as well argue that wireless computer networks will never work, microwave ovens will explode, and cable TV is impossible because of signal losses.
Maybe YOU can develop cheap microprocessor-based detonators, but I'm not aware of any available on the market today.
Wikipedia says thermite is difficult to ignite. I've never tried to ignite it. I'm not aware that glycol oxidation or propane fuel is a common feature of office fires. The ignition point is moot if the thermite is packaged in fireproofed cartridges or sprayed inside the hollow box columns.
I didn't say there was no danger of an airplane striking too high or too low. I said that a retired airline pilot told me that the precision on autopilot airport beacons was +/- ten feet. I said that Aidan Monaghan claims that by 1994, remote controlled 737s were making landings with accuracy within a few centimeters. I said that USAToday said "Military and civilian jets have been landing on autopilot for years." Landing implies a high degree of precision--landing 10 feet too high or to low can be kind of embarrassing.
Precision-manufactured thermite charges can be tested empirically to determine their precise burn times and their effects on steel plate of various thicknesses.
I don't know why the demolition industry does not use thermite, and I doubt you do either. Possibly it has to do with the fact that precision thermite cartridges are not available on the market and, as I said, those in the industry would like to restrict the players to a group that already has licenses for explosives and a lot of expertise in using them.
Your belief that these technologies are impossible and non-existent is quite frantic and irrational. Why are you so emotional about these issues?
intaglio
(8,170 posts)for bulk use such as demolition does not exist. One shot dets for the military do.
What you are implying is that your non-existent, high tolerance dets with encryption would not be microprocessor based - yeah, right.
You also ignore the fact that microprocessors cannot stand long term exposure to high temperatures such as above a fire and neither do batteries. Your radio controlled dets are a complete figment of someone's deranged imagination.
Landing aircraft. Centimeters or feet depending on your source. Actually 10 feet is not a lot because the aircraft sink rate on approach is pretty low and aircraft shocks take much of the impact. If you think auto control is accurate have a look at the landing apron of any major airport and see the varying start points of the tire marks. Oh and where on the Twin Towers was the Doppler radar and landing beacon?
1) Thermite has been in use for 120 years.
2) It is not an explosive it is a slow pyrotechnic reaction similar to, but slower than, black powder.
3) It is well understood.
4) It cannot be used in demolition because of the long burn times. An error of 1% on the cutting time of a thermite charge would result in a variation of more than 1 second between the the completion of the cuts. This would result in an out of sequence collapse and the structure not falling in the footprint required. Contrast this with a a conventional charge where the variation would be measured in nanoseconds. Typically a demolition sequence cannot stand out of tolerance cuts of greater than about 100 microseconds - and that would be pushing it.
5) The cutting time of the thermite charge would depend on how the ignition propagated and on the precise make up of the item being cut. Even in the most high tolerance metals there is a lot of variation of both composition, thickness and crystalisation.
Your belief that the limitations of the materials and devices can be overcome just by wishing the problem away is frantic and irrational.
Ace Acme
(1,464 posts)You are resting on unjustified assumptions.
1. An unjustified assumption that the collapse began at the fire floors.
2. An unjustified assumption that explosive or incendiary charges in the elevator shafts would have detonated prematurely, or not at all because of fires. What is there to burn in an elevator shaft?
3. An unjustified assumption that detonators and charges could not be shielded from high temperatures. NIST's core steel samples only show heating to 480 F.
4. An unjustified assumption that complete cuts are necessary to weaken a structure to collapse.
5. An unjustified assumption that the composition of the steel in the WTC was unknown.
zappaman
(20,612 posts)You can't even make sense!
Ace Acme
(1,464 posts)intaglio
(8,170 posts)I said that there are no mp dets for demolition produced. I also pointed out that the demolition industry would love such dets but that they don't have them because they cannot get them to work sufficiently accurately to drop a building
1) at no time did I say the collapse began on the fire floors. I did say that they were in a "hostile environment" where they would have been subject to extreme heat. It may have escaped your notice that hot gases rise up and are frequently liable to undergo 2ndry combustion. The contention of the conspiracy lunatics is that the "demolition" began on the floors above.
2) Pointed out that thermite can be ignited by long exposure to heat. I also pointed out that microprocessors fail under even moderate heat. I also pointed out that batteries fail under moderate heat.
Oh noes!!! That means that the ebil CIA/NSA/Biderburger/Illuminati has got mini refrigerators which they attached to the charges!!! /sarcasm.
3) How do you shield dets and charges from high temperatures when they are attached to steel which -duh, duah, DAHHHH - conducts heat rather well? Have you now invented a fantasy insulator which would further disrupt the timing of your impossible demolition? BTW you are aware that thermite burns at considerably more than 480F and cuts by melting the steel, which happens at considerably more than 480F. You are aware that steel conducts heat rather well? That means that considerably more than just the area cut by your impossible charges would have been exposed to temperatures vastly in excess of 480F.
Oh noes!!! That means that the ebil CIA/NSA/Biderburger/Illuminati/Masons attached liquid nitrogen coolers around the charges!!!! /sarcasm
4) No, you assume that the demolition was controlled - "Oh look! the tower dropped straight down that means it must have been a demolition!!!!" I pointed out that it is impossible to use thermite for such a controlled demolition because of timing variables and now you want to introduce another variable - incomplete cuts. Such variables would not cancel out they would add and ruin your nonsensical, indeed idiotic, demolition scenario.
5) A lie I actually said that even in well know steel minor variations on thickness and microstructure of steel would add to the variation in cut rate of a thermite charge. Add in your stupid idea that incomplete cuts would be used and you are making yet another variable. BTW over time the normal flexing of tall structures will change the microstructure of steel.
Oh noes!!! That means that the ebil CIA/NSA/Biderburger/Illuminati/Masons/KGB invented a tricorder to scan the structure!!! /sarcasm