NIST Video: Why the Building (WTC7) Fell

[Psy0psAgent]

Dog tags dont melt when when a plane crashes and there are no family members of passengers. Have a nice day.

[ThePeage]

(3) If this is true:

1) Please could you explain why NIST dismissed ANY and ALL “circumstances”, with the exception of fire, based on the absence of a single blast loud enough to indicate the use of the explosives used in conventional demolition?

2) Did NIST ever release the results of the “additional computer analysis” that was done in order to satisfy the team (and the building community) that this was the case?

[ThePeage]

(2) have led to a complete loss of the building if fire or damage from the falling debris of the nearby WTC 1 tower were not factors. The investigation team concluded that the column’s failure UNDER ANY CIRCUMSTANCE would have initiated the destructive sequence of events.”

(My caps) (3)

[ThePeage]

@usnistgov

In para 3 at h t t p : / / nist. gov/ el/wtc7 final_112508. c f m (remove spaces) NIST states:

“In response to comments from the building community, NIST conducted an additional computer analysis. The goal was to see if the loss of WTC 7’s Column 79—the structural component identified as the one whose failure on 9/11 started the progressive collapse—would still (2)

[911debunkerschannel]

World Trade Center 7: An Engineered Collapse - A film based largely on the research and information from the book, The Mysterious Collapse of World Trade Center 7: Why the Official Final Report About 9/11 is Unscientific and False

/watch?v=KHxQ6yzU1qo

[MrKoenig1985]

NIST didn't know the exact ignition source for the fires in WTC7 after collapse of WTC1, like for the 104th floor fire at the west face of North Tower. And why the sprinkler systems didn't work in WTC7 and in the upper region of WTC1, above the impact zone, because the 104th floor sprinklers were served by the water reserve tank on mechanical floor 108-110.

[RonBurgundy161]

@MrKoenig1985 Yes they do. Debris ignited fuel storage tanks within the building.

[The911watch]

NIST never explained how this building could have collapsed in free fall speed. The only way that is possible is with explosivs.

NIST is corrupt.

[MrKoenig1985]

@The911watch

It's called correctly freefall acceleration, not speed.

[HyperColours]

NIST calls this a progressive collapsed! WTC7 fell altogether in one motion in 7 seconds! Not progressively! They cant even model it on the Computer because its not possible! Thermate does not make a bang. Why didn't WTC5 WTC6 not fall after been eating by fire? How did the BBC report it had fallen 21 minutes before it happened? Why don't NIST show there model data and have it peer reviewed? Yow know one day people will realised you lied and then what will you do?

[RavenPrecept]

@HyperColours You must start the timing when the collapse begins. Correctly the buildings destruction started when the fires started. Therefore the collapse took over 8 hours, hardly free fall.

[ZionistsRunTheGov]

Negligence

In

Stating

Truth

[newjack31622]

NIST is a joke.

[elnachopedro]

@usnistgov If you had nothing to hide, you would respond @9Talent11. It looks like you started with your conclusion and worked backwards.

[eleutheromaniac]

so what even NIST admits is an 'extremely rare event' happened to have occured during the biggest terrorist attack in US history? Why is it "conspiracy theorists" are immediately labeled as nutters, yet Coincidence Theorists are hailed as scientifically-minded rationalists? I mean, this has to be one of the biggest coincidences in human history. And even calling it 'extermely rare' is entirely misleading, since actually outside of this incident, it has NEVER happened, before or since.

[LazlosPlane]

@eleutheromaniac You're right. It is NOT a "rare" event. It is an event that has NEVER happened, therefore could never have been predicted. But somehow, firemen, police reported that the "building was coming down," for four hours, maybe longer?

Who knew?

[MegaGuarapo99]

Why go to a university to get an engineering or physics degree when you can just look at TV footage of the collapse of World Trade Center buildings and become an instant Ph.D., complete with experience in strength-of-materials, combustion, explosives, dynamics, the ability to do 3D finite element calculations mentally, as well uncover sabotage plots and the national security secrets of governments? It sure beats studying math, reading textbooks, and actually thinking; reality is too much work.

[BrideAndGroomFilmsHD]

@MegaGuarapo99 Yeah, we might as well just get rid of all of the technical universities since I can gain expertize in and knowledge of structural collapse by spending a few hours trawling conspiracy websites.

[MrJohnnyOldschool]

Well, this is interesting. I've seen simulations that prove that the building could not possibly have collapsed due to fire. Numerous ones in fact.

I suppose though that this video does prove one thing. Building companies no longer need to spend hundreds of thousands of dollars on controlled demolition. They can simply set fire to a floor or two, and have the entire building collapse in on it's self.

[bIZAROsPRMN11]

Did NIST recommend that a criminal investigation be initiated regarding the willful destruction of forensic evidence, i.e. selling the World Trade center 7 steel for scrap prohibiting a forensic examination of one single piece of steel from WTC 7?

[kousoulides]

The Abu from Simpsons states:

We really have discovered a new type of collapse here!!!!!!!

A fire induced progressive collapse..

What a sick joke.

Haven't seen explosions? well I've seen them in HD..

[CHIPSTERO7]

Why is anyone surprised that NIST is concealing the demolition? NIST is not an independent research institution but is an agency of the US government which automatically renders their evidence suspect. Oddly their FDS-simulator assumes no thermal-conductivity of the steel, the collapse of the building in the model shows contorting of the structure that is not evident in the video, and they rule out demolition entirely on the basis that the noise from WTC7 did not exceed 120-decibels a mile away.

[roxxphatcox]

Why has NIST failed to produce a scientifically replicable experiment in an effort to prove the theory`s probability/validity? The failure modelling software being used would necessarily allow freefall over several floors and countless structural members. On accord with the fundemental laws of physics , this is factored into any physics modelling software. The deceleration between floors/structural members on the vertical axis would always be in a measurable quantity. NIST`s appearantly does not

[ghana25]

There is no more need for controlled demolition companies, just light the building on fire and it will collapse into itself. Cheaper and easier, everybody benefits.

[HavocGunStar]

I disagree with one point, that the collapse of the North Tower was the only cause of fire in WTC7. WTC7 and the Post Office next door were directly in line to recieve damage from ejecta and plane parts from the South Tower impact.

Based on that, and witness commentary, I believe fires started in WTC7 when the South Tower was hit. Not that the collapse of the North Tower did WTC7 any good. It started more fires, and gouged out walls on the south face.

[Carryon871]

NIST: Trololololol

[livingaftermidnight]

NIST said they found no evidence of explosives in any of footage they studied. Well, this video NIST released from a lawsuit against them has audio evidence of an explosion just before collapse. Link: /watch?v=783mtK_0zhE

This explosion on this next link was from earlier in the day of WTC 7. Link:/watch?v=0YvrKfWkxdw

NIST, I request that you issue a retraction and correction of your statements that there were no audio evidence of explosives found in the videos that day.

[86zeruel]

High school physics is enough to prove that NIST is lying.

(And the computer model looks ridicously different from the actual collapse.)

[joep3300]

The truth about the collapse has nothing to do with liberal or conservative opinions, but rather with the laws of physics. Dr Sundar says NIST has discovered a new form of collapse that defies the laws of Physics. Perhaps all the architects & engineers in the world need to go back to school to learn about it.

[jizzmonger]

@joep3300 This is what happened to WTC 7.

watch?v=H0Xbmfais1E&feature=re­lated

[0pocketpenis0]

you only need some diesel and a lighter to get rid of those core columns!...man those demolition experts are dumb! using shape charges...il do you're next demolition for $50 and a chocolate muffin.

[CuzPBz]

lolllllllllll this video is funny, there simulation doesnt even show a uniform colapse

hight rise are safe lol what a joke.....

[StevenM818]

It appears NIST released 2 versions of the footage seen at 0:15 . Through a recent FOIA they released a long & short version of the same WTC-7 "collapse" video. In the short version (CBS-Net Dub5 09) there's an explosion just before the east penthouse drops. In the longer version (CBS-Net Dub7 47) the explosion has mysteriously been removed. I have the short version uploaded here: watch?v=0j8XN3iKLak

Wear headphones while viewing, or turn up your speakers. Also see description for more details.

[usnistgov]

@StevenM818

The video footage released under the FOIA request was copied from the original video exactly as it was received. The video and audio were not edited in any way by NIST. NIST received video footage from many different sources and audio levels may be different between these sources.

[MrKoenig1985]

@usnistgov

Is there any guarantee of your statement? In many videos the beginning of the collapse is missing. It seems unlikely that so many videographers turned off their cameras just before the buildings started to collapse.

[iBlindGame]

@StevenM818 During the 8/21/08 press conference, NIST showed to the reporters the simulation that looks exactly like the fall of WTC7. It certainly is difficult psychologically to question such an exact reproduction of the fall of WTC7...unless you tell yourself: "Have they released the simulation data? Are they going to be honest about this?" It turns out, they weren't. No usable simulation data has surfaced.

[flanksteak2]

@iBlindGame What is stopping you from conducting your own simulation using the same Data as NIST other than the fact that you don't have the knowledge or resources to do so?

[ryangi5]

Those liberals who think that 9/11 was an inside job, have lost contact with reality to a degree that can only be described as psychotic. (To normal liberals, I understand that these 9/11 nut-jobs represent a small fraction of all liberals.) I'm truly in awe sometimes of how much liberals exude the very characteristics they profess to deplore. How about open-minded? These nut-jobs shout down anyone who disagrees with them and spew more non-sense. They have no clue about what they are saying.

[TehWinnerz]

the problem is with conspiracy theories is that whenever some official voice comes out and "proves" that whatever happened wasn't a conspiracy it will never be good enough for some people who will always believe that its always Government propaganda and lies...

[gunthaarz]

this video actually says _nothing_. It certainly proves nothing, since it does not refer to _any_ _actual_ data. And in fact , there are 100's of witnessess and several videos that record a Large explosive blast sound that more than obviously enough is way above 120 desibel. This video FAILS on ALL points it pretends to cover. I guess NIST just cant find enough liars anymore. Friendly advise : Get new jobs before peoples anger with your fraud take a permanent hold...

[RC365247]

Junk science!!! 1333 verified architectural and engineering professionals totally disagree with these findings!! ae911truth . org

[ryangi5]

@RC365247 Look up the logical fallacies of appeal to authority and appeal to popularity. Then come back here and explain to us how your point is not a text book example of a logical fallacy.

[organisten]

@ryangi5 actually, the same by inference can be said of yours. You do mean to suggest that since this is NIST, that it therefore be authoritative?

[c295014]

N.I.S.T

NEED. ILLUMINATI. SUPER. THERMITE.

[ThePassiveFist]

Building 7's collapse was unusual - it's never happened before or since.

Unusual in the extreme.

Long-span floors expanding from the heat?

Loss of support across the whole building?

Sounds like dodgy science to me.

How come they never even considered explosives?

It's plain that the whole investigation was compromised.

That's all.

[ravenblack6]

"Investigators beLIEve"

believe- verb= to have confidence in the truth,existence or reliability of something, although with out absolute proof that one is right in doing so. To suppose or assume; understand.

[TheMKMonarch]

NIST has also no explanation for the simultaneous bursting of multiple windows on various floors along the eastern core columns (79, 80, 81) and then along the western core columns at the north side, just seconds before the global collapse of WTC 7. At this time, the facade has not yet been deformed.

[TheMKMonarch]

"The NIST team found no evidence that explosives were involved in the collapse"

.

Of course! NIST used the standart method of demolition in their hypothetical blast scenario. And they used the high-energy explosive, namely 4kg of RDX which cut trough the thick steel of column 79.

Other, unsual demolition ways were not taken into account, such as the breaking of connections of the structure by smaller cutter charges. Also other types of explosives were not considered in their scenario.

[wafelijzerstekker]

If explosions caused the collapse you should be able to hear it? I thought it could collapse without any explosives XD fail

[livingaftermidnight]

@wafelijzerstekker Look at these:

/watch?v=783mtK_0zhE

/watch?v=0YvrKfWkxdw

[ForbiddenHaze]

This video doesn't mention anything about it being an inside job and that there actually WERE explosives. This video lies.

[baihbalm]

The first and last of it's kind to fall without resistance due to fire... took quite a stretch of the imagination to come up with this farce. How do you guys sleep at night?

[SexyMelon]

Everyone at NIST will bear a mark of shame for allowing this "explanation" to be presented here.

Your calculations are baseless, your model looks nothing like what happened, and even though the final model, by your own admission, "has only a small chance of occurrence", you state that is how it DID happen, without a shred of evidence to support it?

This is not acceptable. Both law and common sense dictate all you needed to do was to examine the steel for signs of heat exposure. You did not.

[kingskins0]

"having a collapse from fire is a very rare event", they contradict themselves, as they say it happened 3 times that same day

[kingskins0]

"a new kind of progressive collapse"......BAHAHA how stupid do you think i am

[harisman22]

hey if your pants got on fire would you fall down like wtc 7 in a perfect manner or kinda like the witch from the wizard of OZ.

[totoroben]

Go ahead click on the link for more info........ oh wait it doesn't exist anymore.  I guess you'll have to believe the cheesy computer animation for what it is.

[allaprima99]

This is an excellent analysis of the collapse of WTC7. Not putting out the fires in the building which burned for 7 hours was the critical fact of the collapse. Steel beems are not static structures, they expand and contract even under normal temperatures. But will expand, sag and cause structure failures under extreme temperatures (1,000 degree F).

[jesusgrc1762]

If you are going to be very scientific, open-minded, etc, then one has to at least recognize that their "computer model" looks NOTHING like the ACTUAL collapse. Therefore, their theory would have to be taken on the value of "authority" rather than any conclusive evidence.

[roxxphatcox]

Question for NIST: Why is there no explanation for the collapses? WTC 1/2/7.

Since this was the main objective for the report. As of this date there is

proposed hypothesis for the initiation of failure mode, And none of these hypothesis have been validated/proven through replicable experimentation. Not even the dataset for the computer simulations has been released for independent verification rendering the conclusions of the reports

at best: well-documented suggestions.

[harok375]

Which LSDYNA analysis was the animation based on? It looks to me like it was based on the fire/no impact damage model.

[dan917x]

WTC7 has been proven that it fell from free fall speed for at least 100 feet. Impossible to do without something removing columns such as explosives.

[rubenpena]

This video is a joke. The US Govt. & NIST are putting out dis-information in an attempt to distort & manipulate the truth, and confuse the public. In addition to all the comments below thus far, this video ALSO doesn't explain the following:

1) why the lease owner of WTC 7, Larry Silverstein, gave the US Govt & NYC authorities permission to "Pull It", i.e. execute a preplanned controlled demolition to intentionally collapse the building. Why do this?

..... to be continued .....

[rubenpena]

Why not simply contain the fires in WTC7 as has always been done in all the history of all firefighting? Whats the rush in collapsing WTC 7 on the very same day of the 911 attacks, with already so much incredible death, destruction, chaos & confusion? Check out the video:

Link: w w w . y o u t u b e . c o m / w a t c h ? v = p p z X 1 3 M x J o c

[jizzmonger]

@rubenpena

If that's the case then why do you suppose they approve your comments on this video?

[1234proximus]

Gutes Video!

[daveyboi03]

all of this can't explain why they pulled the building

[MrDoublehappy]

A lot of important agencies including the secret service had offices in that building, Rudy let it slip in an interview, I think he regretted saying it after wards but it was too late by then he had already blabbed it out.

[nesNYC]

Super-nanothermite charges don't make much noise only lots of white smoke and cut big steel beams like butter. They can also pulverize concrete, create pyroclastic flows and heat the underlying deb rise to create molten pools of iron and steel just like was observed when the site was being cleared.

[apezak]

wow the construction industry has heared the prayers! There won;t be any building collapsing in this unordinary way in the future.

[MrRoguepenguin]

What a steaming pile of horse crap.

You know the one thing scarier than knowing that this was a controlled demolition? It is that there are millions of professional people out there that still believe this NIST fairy story!!!

[fireofenergy]

"Looks like a perfect implosion"

to me too! (didn't know fire can do that to steel).

Gov needs to reconsider spending half a billion dollars on destroying U-233 needed to start THORIUM fission in molten salt reactors, ~1,000 better than conventional nuke plants! Instead, spend it on the LFTR development for complete SOLUTION to CO2 issues. (or at least spend it on advance solar automation and electrical storage...)

[MikeG11986]

Only people who don't understand physics would believe this.

[SixT4]

@MikeG11986 So you have a strong education in physics and a career full of relevant professional experience? If not, I don't see how you're more qualified than NIST to comment.

[fookthefrench]

@MikeG11986 I hold a physics degree. The testimony presented in this video seems to be perfectly reasonable to me.

So I'm curious: how did you develop your intuition of physical principles?

[zenoist2]

good vid ,showing the official explanation. The actual truth is totally contridactory to this.

Oh, we'll rule out explosives or thermite before we even start.

No wonder it took 7 or 8 years to come up with something remotely possible explaining the totally impossible physics.

[jazzfan5000]

Get a life!

[zenoist2]

Explosives werent even tested for.

Reason?

They didnt produce 130 decibels half a mile away.

What the hell kind of explosion is that?

It has to be a totally crap criteria on which to ignore evidence.

Tons of eyewitnesses reported explosions.

Isn't that a really pathetic excuse for not testing for explosives or thermite?

[zenoist2]

its such a rare event as to be impossible in fact. Truther posts are about physics and whats possible and impossible

This is impossible in physics if you accept the fire explanation.

Im one of these nutcases who beleive laws of physics can not be changed. No wonder it took so long to come up with a totally laughable explanation once explosives or thermite were instantly removed from the so called investigation .

Exactly like a murder case the first thing you do is to destroy any evidence.NOT

[shevegen]

A perfect cover up - even if you bring down a building in a controlled demolition, you only need a few experts building another story.

It just has to be plausible.

[soylentgreenb]

Yeah, you just need the few thousand experts who have studied it in detail to be in on it. Get a grip.

[Sloppy998]

Uhuh. Sources please? Or are you living in an imaginary world? Thousands of experts... lol... get a grip.

[flanksteak2]

I didn't know this video existed.

This is great!

[Skeptic121]

Does anyone else wonder why they didn't finish the similation?

[Diabolous3x]

"...and then we decided to 'pull it', we made the decision to 'pull' building 7..."

[swordsworth]

No one decided to pull the building. Silverstein was talking about the rescue effort, if you actually pay attention to the entire quote. In any event, Silverstein didn't have the authority to tell the chief of the NYFD to do anything. He said, "There's been such tremendous loss of life, maybe we should just pull it (referring to the efforts of the NYFD to put out the fire)." Face it, you have no real evidence of anything.

[TheRedneckAtheist]

I can't stand reading twoofer posts, nothing but incomprehensible rants and blatant stupidity.

[accersitusmaximus]

There is video evidence of yellowish molten metal pouring out from the towers. NIST explanation is debunked. It's not aluminum, because molten aluminum is silvery white. Molten iron and steel is yellow.

[Crit0]

"..molten aluminum is silvery white."

Except when it isn't.

/watch?v=NU956GwJDRQ

/watch?v=U8oFAJWwhnA

[tomestubbs]

I have done aluminum casting it is always silvery with a subtle red underglow. and it would solidify relatively quickly. It is what it is, and it isn't what it Isn't!

[accersitusmaximus]

High resolution WTC7 footage:

WATCH?v=oQeQi5XXfz0

Misinformation often arises from poor research, biases, and misinterpretations.

Misinformation may also originate from disinformation, a deliberate effort to mislead, where the goal of the disinformation is to recruit sincere and unwitting individuals into propagating misinformation. Disinformation techniques have a history of use in military campaigns and are an integral part of false flag operations and information warfare.

[accersitusmaximus]

[NICSTAR 1A 3.6]"constant, downward acceleration during this time interval. This acceleration was 32f/s^2,(9.8m/s^2), equivalent to the ACCELERATION OF GRAVITY."

"free fall acceleration can ONLY occur when there is NO STRUCTURAL COMPONENTS BELOW IT"

- Shyam Sunder, NIST lead investigator (Q&A briefing).

[accersitusmaximus]

Google "new footage WTC 7"

Several hundred thousand tons of constructional steel.

Where is the fire?!

[accersitusmaximus]

"As a professional city planner in New York, I knew those buildings and their design. When I saw the rapid collapse of the towers, I knew that they could not come down the way they did without explosives and the severing of core columns at the base.

Moreover, the symmetrical collapse is strong evidence of a controlled demolition. What we are faced with is a lie of such proportions that even to suggest it makes one subject to ridicule and scorn."

- David A. Johnson, B.Arch,

MCP, PhD, F.AICP

[UDoHaveMyName]

This video is laughable.

A monkey could watch a video of the WTC7 collapse and determine with 100% accuracy that it was a controlled demolition.

[jurgitall]

thank you, one question...didn't the east side fall first, then a slight pause, and the rest going? It took a lot longer than what most videos show

[Crit0]

Yeah. Most collapse videos on youtube are circulated by the conspiracy theorists. They deliberately cut out the internal collapse to make the whole thing look deceptively fast.

[vengencefrom1979]

how nist can even get up in the morning is beyound me.

[danielwvu]

ummm....ty....i think?

[9Talent11]

hahhahahahaha you must be kidding! the model looks nothing like the actual collapse, this "explanation" which "is very unlikely to happen" is such a joke. nist, why dont u give out the data for your model? where does the molten IRON, not metal, come from? what about the the freefall speed you had to admit? what about the nano-thermite? how comes that all collums fail at the same time? it tells a whole lot that this video is only 3:40 minutes long.

[peterbob101]

where is your data and testing?

[CJOKUSAP]

So, in essence, Sunder's objection to a controlled demolition, after admitting that one column was the catalyst to the collapse, is that nobody heard a "BOOM!"?

[usnistgov]

Thanks for checking out our video. Please add your comments and let us know what you think. We will be reviewing and then posting comments as long as they are on topic, respectful and do not promote specific products or services.

[femr2]

usnistgov... 2 months ago, I asked you a couple of questions, after which you directly responded directly to me. I then posted two further questions in direct response to your answers. Both questions are now over a month old and have not been answered, despite me repeating them to you over PM and requesting any reasons why you would decline to answer.

Could you explain to me why you have not answered my questions please ?

They are very clear and directly relate to the answers you provided.

[achimspok]

mexxxx, the website ae911truth[dot]info is really funny! Is it your web site? If so get a physics book for children and everything will be enlightened.

e.g. why a free falling penthouse PLUS a free falling outer shell IS JUST a free falling penthouse and a free falling outer shell BUT NOT a double fall time. (otherwise you have to consider the gash and would get a fall time of about 7 hours)

Btw, explosions were recorded and broadcasted after WTC1 came down. NIST don't know it. Bad bad sign!

[Pikman01]

Those explosive sounds heard from the WTCs 1 & 2... Could some of those sounds be from WTC 7?

[me91456]

not likely, because WTC7 collapsed 7hours after the twin towers. The sounds heard from tower 1 and 2 were likely caused from falling bodies (it was reported they sounded like grenades when they hit the ground) or it comes from stress on the building. like girders snapping etc.

[achimspok]

Explosion sounds were recorded and broadcasted but NIST don't know it because they never checked "what happend" BUT looked for signs for what should have happened.

And finally they did an oxygene guided simulation and took care that the fire around column 79 burned for hours while the visual evidence (in the NIST Report) tells the contrary and ALL similar areas burnt out in about 30min. Just read the Report!

[bloggulator]

The best analysis comes from David Chandler, who examined the *evidence*. NIST is flagrantly guilty of dry labbing, while Chandler did the MATH. The reason why NIST refused to acknowledge "freefall" acceleration was because buildings *never* fall in this way under natural circumstances: the only mechanism that can produce such a result is demolition via explosive charges. This probability was excluded from the NIST "investigation" because their conclusion was prewritten: classic bad science.

[me91456]

If that is true then the NIST would not have posted your comment. You should have a look at ae911truth[dot]info which evaluates the mistakes made by david chandler.

[achimspok]

ae911truth[dot]info is really funny. It's a joke isn't it? Hey, they forgot the gash on the north side. The gash collapsed at about 10:28am. Let's say WTC7 fell in about 7 hours and far more than free fall.

(If this is your web site, take a physics book for children. Everything will be explained.) e.g. why a free falling penthouse plus a free falling outer shell are just a free falling penthouse and a free falling outer shell BUT NOT a collapse of the double time.

[usnistgov]

Thanks for checking out our video. Please add your comments and let us know what you think. We will be reviewing and then posting comments as long as they are on topic, respectful and do not promote specific products or services.

[femr2]

NIST...

Please explain the mechanism which allowed the 2.25s period of free-fall during the descent of WTC 7.

It is clear that, at the very least, the whole North facade descends almost symmetrically, which implies failure of all facade columns almost simultaneously.

No such failure is evident in your animations or described within the report.

Please detail the mechanism which led to the almost simultaneous failure of all North Facade columns to allow 2.25s of freefall.

[usnistgov]

The visualization of the computer analysis shows only the initiation of the collapse sequence and during this time the deforming structure did pose resistance to collapse. The collapse occurred in two stages: First, all of the interior support columns failed, and then once this support was removed, the exterior columns also failed.

[usnistgov]

A detailed NIST analysis shows that during the first 1.75 seconds of the video as the top of the building's north face begins to fall there *was* resistance (and building fell at a rate slower than free fall) as the exterior columns in the lower stories buckled. The middle 2.25 seconds of the video show the building collapsing at essentially free fall speed because once the exterior columns had buckled and the interior supports were already gone, there was negligible resistance.

[usnistgov]

Finally the last 1.4 seconds is again slower than free fall as the structure encounters the debris pile below. Overall, the video analysis shows that the outside building shell fell at a speed 40 percent slower than free fall.

[jizzmonger]

@usnistgov

Good comments.

[femr2]

NIST...

In this video (watch?v=WnXeUIaYj3k) I compare the deformation of WTC 7 to the NIST animations.

The animation most resembling the descent shows significant deformation of the SW corner not present in video. The animation also shows failure of internal columns on the east side, but appears to show ~2/3 of the remaining internal columns still resisting descent at the end of the video, at a time within the period of free-fall.

Why did 2/3 of the internal columns not resist the descent ?

[femr2]

NIST...

"The collapse occurred in two stages: First, all of the interior support columns failed, and then once this support was removed, the exterior columns also failed."

This statement is a direct contradiction of the information presented within the NIST visualisation videos, which clearly show that roughly 2/3 of the interior support columns have not collapsed whilst significant deformation of the exterior columns is taking place.

How do you explain this apparent contradiction ?

[Skeptic121]

They mystery of WTC7 is not that it collapsed but the MANNER in which it collapsed. Many steel buildings have been damaged in war, have caught on fire, and have collapsed. NOT ONE has collapsed as WTC7 did: straight down and all together. Wrong? Find a video!

NIST has now admitted WTC7 dropped at free fall acceleration for 2.25 seconds, meaning 25 meters of vertical support was suddenly and completely removed (25 = 1/2 * 9.8 * 2.25^2). Not gradually weakened by fire; suddenly GONE.

[truthl0lhurts]

Since when, small fire melts steel? Furthermore, any scientist or engineer knows that 4 inches thick and O in the H shaped steel does not melt under such small fire and there were examples of way bigger fires on high rises around the globe that never were capable of bringing the whole structure down at all. Above all WTC7 comes down as in a perfect demolition style. Larry Silverstein Lease said that the fire dept demolition it. Your simulation is unconvincing and does not cover all the facts

[blueshadow1996]

small fire can weaken steel..do a vid search for Shermans neckties,,you will see a civile war re=enactment of Union spldeirs ripping up railroad tracks and heating them in a small fire then wrapping it around a tree..

[simonshack]

WTC7 STUDY

watch?v=w4Vrsjs_cLg

[usnistgov]

Thanks for checking out our video. Please add your comments and let us know what you think. We will be reviewing and then posting comments as long as they are on topic, respectful and do not promote specific products or services.