[YT] NIST has reversed its earlier denial of freefall and acknowledged a period of freefall comparable to this analysis in their final report on WTC7 released in November 2008. They did their own measurement with a point near the center of the roof line and came up with an acceleration of 9.81 for approximately 2.25 sec. Their report did not, however, face the consequences of this acknowledgment: that ALL RESISTANCE was instantaneously removed across the width of the building, supporting pre-planted explosives as the cause of the collapse.
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(Original comment comments follow)
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Contrary to the August 2008 NIST report on WTC7, the acceleration of Building 7 is measured and is found to be indistinguishable from the acceleration of gravity over a period of about 2.5 seconds of fall.
During the first round of questions in the Aug 26, 2008 NIST Technical Briefing (at 1:01:45 into the presentation) the following question was asked by David Chandler:
"Any number of competent measurements using a variety of methods indicate the northwest corner of WTC 7 fell with an acceleration within a few percent of the acceleration of gravity. Yet your report contradicts this, claiming 40% slower than freefall based on a single data point. How can such a public, visible, easily measurable quantity be set aside?"
Dr. Shyam Sunder replies:
"Could you repeat the question?"
[the question is repeated by the moderator, leaving out the word, "competent" as well as the last sentence]
"Well...um...the...first of all gravity...um...gravity is the loading function that applies to the structure...um...at...um...applies....to every body...every...uh...on...all bodies on...ah...on...um... this particular...on this planet not just...um...uh...in ground zero...um...the...uh...the analysis shows a difference in time between a free fall time, a free fall time would be an object that has no...uh... structural components below it. And if you look at the analysis of the video it shows that the time it takes for the...17...uh...for the roof line of the video to collapse down the 17 floors that you can actually see in the video below which you can't see anything in the video is about...uh... 3.9 seconds. What the analysis shows...and...uh...the structural analysis shows, the collapse analysis shows that same time that it took for the structural model to come down from the roof line all the way for those 17 floors to disappear is...um... 5.4 seconds. It's...uh..., about one point...uh...five seconds or roughly 40% more time for that free fall to happen. And that is not at all unusual because there was structural resistance that was provided in this particular case. And you had...you had a sequence of structural failures that had to take place and everything was not instantaneous."
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Note that:
--He acknowledges that freefall can only occur if there is no structure under the falling section of the building.
--He acknowledges that their structural modeling predicts a fall slower than freefall.
--He acknowledges that there was structural resistance in this particular case.
--He acknowledges that there was a sequence of failures that had to take place and that this process was not instantaneous.
Thus, he acknowledges that their model is at variance with the observable fact that freefall actually occurred. Their response is to hold to their model, deny that freefall occurred, and put up a smokescreen of irrelevant measurements that obscure the reality.
33 Comments
shuacScience! It works, bitches.
eric3579*promote
siftbotPromoting this video and sending it back into the queue for one more try; last queued Wednesday, December 17th, 2008 7:18am PST - promote requested by eric3579.
charliemsays...Im usually of the opinion that 911 troofers are all out of their minds bat-shit crazy...because none had given solid evidence to back their insane ideas up.
But this....this is different.
Cant argue with that.
If his measurements are correct, then hes got the best resolution for a velocity profile you are ever going to get...ever, with that simple little tool.
Im...kinda shocked tbh, to see that -9.8m/s/s was a bit of a jaw-dropper.
schmawyI'm still bat-shit crazy thank you Charliem, but that doesn't change the evidence at hand.
>> ^charliem:
Im usually of the opinion that 911 troofers are all out of their minds bat-shit crazy...because none had given solid evidence to back their insane ideas up.
But this....this is different.
Cant argue with that.
StukaFoxsays..."I'm a high school teacher"
Correct. What you're not is:
1. A structural engineer specializing in skyscrapers.
2. A mathematician.
3. A Ph.D. in physics.
4. An expert in video analysis.
5. An expert in forensics.
6. An architect.
7. An expert in failure analysis.
8. The guy who designed the building in the first place.
You know who ARE all these things? The people who released the NIST report. The people who had more video than you. The people who put their hands on the steel. The people who interviewed eyewitnesses. The people who ran the labs. The people who ran repeated simulations of the collapse based on models about a million times more complex than your free software and video off the internet.
So what you, and the rest of the chowderheads in the Scooby-Doo Conspiracy Movement, are telling us is that all these people are 1. lying 2. complicit in mass murder and 3. THEY WOULDA GOTTEN AWAY WITH IT IF IT HADN'T BEEN FOR US DARNED KIDS!
Thanks for being tools for Osama, you bags of shit, now go analyze how your heads got shoved so far up your asses.
schmawyIt doesn't matter how how complex a model is, you could run FEA on a million joints, beams, and structural connections and prove whatever you like. This is an accounting of observable phenomena, known to some as reality. I think your emotional reaction is out of proportion with the video presented.
Duckman33>> ^StukaFox:
Thanks for being tools for Osama, you bags of shit, now go analyze how your heads got shoved so far up your asses.
All I got to say to that comment, and the others in your post is: ROTFL!
So If you're not with us, you're against us is it? Tools for Osama?? Again, ROTFL!
How about this; Thanks for being a TOOL! Go back to believing everything you are told like a good little sheeople.
Disclaimer: I'm not saying 9/11 was an inside job. But there's definitely some shenanigans going on.
nibiyabiCongrats for posting the first 9/11 truther video that I didn't downvote.
StukaFoxsays...Here you Troofers (read, "Batshit Nuts") go: David Chandler himself shows up to defend his accusation of complicity to mass murder by the scientists at NIST, tries to bullshit actual mechanical engineers, and gets blown out of the water with the very same "evidence" presented in the joke of a video above.
http://forums.randi.org/showthread.php?t=128194
Duckman33>> ^StukaFox:
Here you Troofers (read, "Batshit Nuts") go: David Chandler himself shows up to defend his accusation of complicity to mass murder by the scientists at NIST...
http://forums.randi.org/showthread.php?t=128194
How is anything to do with building 7 "mass murder"? No one was in the building when it came down.
schmawy>> ^StukaFox:
Here you Troofers (read, "Batshit Nuts")...
I see a discussion on a James Randi forum buy regular joes like us, several of which are very curious about Chanler's claims, some agreeing, some claiming to debunk. I don't see anyone claiming to be a mechanical engineer. Do I have the correct link?
eric3579See also
http://www.videosift.com/video/NIST-on-the-Freefall-of-WTC7-Wrong-Answer
StukaFoxsays...Oops, even more of Chandler's bat-shittery debunked: http://www.ae911truth.info/tiki-index.php?page=Freefall+Speed
Because if the NIST is lying about the causes of the collapse of WTC 7, they would be de facto complicit in the entire scheme of 9/11.
"Hi, this is Evil Boss Overlord. Hey, look, I know you're all working on that whole WTC7 collapse thing, but I need you to do something: I need you to totally ignore all the evidence you've found of a pre-concocted collapse and come out with a report that says the collapse was the result of structural failure. Yeah, I know, 3,000 people dead -- what a bummer, eh! -- but it's really important for the Evil Master Plot -- what? I know it's obvious that we murdered those people, but is telling the truth now going to bring them . . . yes, yes, yes you're professionals with reputations to uphold and -- what ethics?! Christian, schmistian! Look, just ignore the 3,000 people we killed and release the damned report!"
Argsays...He implies that his margin of error is only 1% because his final answer of 9.88m/s/s is within 1% of the known acceleration due to gravity. This is faulty logic. The known value of acceleration due to gravity plays no part in the calculation of the error of his results.
His errors will be introduced by the distance measurements that he is taking in both his calibration measurements and the location of the roof in each frame.
He states that the known width of the building is 100m. Is this the width when looking straight on? Is this video looking at the building straight on? If not then he is overestimating the width of the building in the video.
He is using the height of the 29th floor and the height of the roof for another distance calibration. There are a variety of ways including perspective and the grainy, low resolution of the images that could lead to him overestimate the height of the building.
Any overestimates in his distance calibrations will result in an overestimation of the distance moved between each frame of animation, which in turn overestimates the velocity of the measured point on the roof, which in turn results in an overestimation of the acceleration.
His final answer of 9.88m/s/s is actually faster than free-fall! So he must be overestimating his distances somewhere. The question is by how much?
StukaFoxsays...>> ^schmawy:
>> ^StukaFox:
Here you Troofers (read, "Batshit Nuts")...
I see a discussion on a James Randi forum buy regular joes like us, several of which are very curious about Chanler's claims, some agreeing, some claiming to debunk. I don't see anyone claiming to be a mechanical engineer. Do I have the correct link?
Post #32 by tfk:
"Nice to meet cha. I ought to be able to help you out with this. I'm an experienced mechanical engineer, so this stuff is straight forward."
Psychologic>> ^Arg:
He states that the known width of the building is 100m. Is this the width when looking straight on? Is this video looking at the building straight on? If not then he is overestimating the width of the building in the video.
If the video is taken from an angle, wouldn't that mean that he was underestimating the width of the building in the video? For instance, if the roof is 100m across then from an angle it would be even longer. If he were seeing it from an angle (I can't tell) then he could be looking at something that could be up to 141m wide (45-degree view if the building is square).
In that case when he estimated how long it took for the building to drop 100m (or how far it dropped in one second) then the building would have actually dropped more than his estimation, meaning that his estimation would show a slower acceleration than what actually happened. Since that would put the acceleration well above gravitational force I don't think that is the case.
However, that doesn't mean there aren't errors. I wonder if he authenticated the time scale of the video. If that was faster than normal for any reason then it would make acceleration seem faster. This needs to be verified using multiple videos from other angles before we can draw confident conclusions.
If it is correct though, that's a big drop with no resistance. It looked like the initial velocity of the building at the beginning of those 2.5 seconds was 1.5m/s. That would mean the building dropped nearly 35 meters (114ft) without anything slowing it down. The implications of that are pretty big, so I'd definitely have to see some confirming calculations with multiple other videos before believing it.
schmawyYeah, "TFK" seems pretty sure of him/herself,perhaps justifiably, but there are several dissenting opinions as well...
#1 ...At least, that's how this layman understands it.
#8...I can help you. The free fall proves that WTC 7 was a controlled demolition. Science has proved that.
#40...Actually, I have never read such an awful report as the NIST WTC7 report. Pure propaganda! The structural analysis after initial failure is simply not correct. (this user claimed to create his or her own finite element analysis model, so probably knows a thing or two).
ravermandamnit... you dont have to be an engineer to watch this collaspe in a smooth straight down way.
There is NOTHING that makes it seem even remotely like a collaspe due to fire damage. I can't believe people believed this even when their eyes show something totally different.
volumptuous*lies
siftbotAdding video to channels (Lies) - requested by volumptuous.
Argsays...Do you believe your ears? The sound created when the charges of a controlled demolition go off is tremendous.
volumptuousI find it amusing that people with such intelligence can overlook the fact that all this conspiracy shit is a pack of fucking lies.
This is like arguing about where those pesky WMD's are hidden, or if bigfoot is real.
TROOF!!!!
Argsays...No, I was thinking of it this way. If you know that a piece of paper is 10 inches across then if you look at it from any angle other that straight on it will look less than 10 inches. When you look at it edge on the paper almost disappears completely!
If you look at the piece of paper from an angle of 45 degrees it will appear to be (10 divided by the square root of 2) inches wide (about 7 inches). So if you look at a video of this piece of paper, taken at an angle of 45 degrees, and you notice that the paper covers 50 horizontal pixels, you cannot say that 50 pixels equals 10 inches in the real world. That would be an overestimate. 50 pixels actually equals about 7 inches because the video is from 45 degrees.
schmawyStuka, I really don't mean to offend anyone with this video, and I guess you have the right to throw epithets at people like me for questioning the events of that day. For all I know you lost a loved one on that day, or as a service member in the wars that followed, so I don't want to challenge what you may hold dear.
I do know that what I'm seeing is a historical first, a building with scattered fires and questionable and unsubstantiated structural damage falling like a dropped curtain. I go back and forth on what the cause could have been, and was for a time comfortable with NIST's original assumptions that the emergency generators were pumping diesel into the blaze, but they recanted on that detail.
I have to work pretty hard to think of this as a natural phenomena of building failure. I know you don't trust intuition or what we see with our own eyes, but do you see it? Do you rely on reports and what people say on websites? Jeez, I just donno.
And Volumptuous, I removed it from the lies channel, because I don't know who's lying. Sorry.
rottenseedThose who can't do, teach. Those who can't teach, write a book about it. This guy shouldn't be let near anything to do with physics.
This is sooooooooooooooo fucking stupid. He claims that taking the average acceleration is inaccurate yet he uses 2 data points to take the slope of the velocity vs time graph which IS the average acceleration. If you look at the graph before he puts that gay green line over it you can see little dips in the graph that shows that it slows down at certain times, probably as its hitting the floors below it. As the building is SO massive as it gains velocity the falling sections have a great amount of momentum. An object with a high magnitude of momentum is hard to slow down.
This is effing preposterous.
*lies
incited the *waronterror
I wanna take it off the engineering channel too as this is a disgrace to anybody that understand anything about physics...
siftbotAdding video to channels (Lies, Waronterror) - requested by rottenseed.
schmawySick of it. I just had some questions and I can't handle the assholery. Sorry you wasted a promote, Eric. *kill
siftbotPermanently discarding this video - kill requested by submitter schmawy.
StukaFoxsays...Stuka, I really don't mean to offend anyone with this video, and I guess you have the right to throw epithets at people like me for questioning the events of that day. For all I know you lost a loved one on that day, or as a service member in the wars that followed, so I don't want to challenge what you may hold dear.
Your video shits on the scientists at NIST and all the hard work they did to uncover the cause of the collapses on 9/11 and hopefully prevent future disasters of their kind. It calls the scientists at NIST outright monsters, amorally complicit in the mass murder of 3,000 Americans. It seeks to erase their exemplary service to this nation and replace it with a shit-smear of empty accusation. And it libels these men and woman for nothing more than the self-aggrandizement of complete nobodies who hitched their wagons to the events of 9/11 -- parasites on the dead of that day.
FadePersonally I find it hard to believe that a highly reinforced building that housed offices of orgs like the CIA and NSA could collapse due to fire, when no other building of the same type has been brought down before.
schmawyWow, I get called a bag of shit, and the fucking Admin upvotes it. Rough.
rottenseedyou're not a bag of shit...i wuvs you :*