The science of why it had to be controlled demolition, in laymen's terms

Originally posted by ANOK
^It's funny that the de-bunkers think the penthouse collapsing is some kind of proof it wasn't a CD?

Actually the penthouse is a classic CD 'kink', take out the central columns first and the outer walls will then fall inwards, which is what they do with large buildings. It could not be more obvious that 7 was a controlled 'pull'...

Who cares if it was 10 or 14 seconds? What a useless waste of time argument.
You really think 4 seconds makes any difference?

Actually, it's 9/11 conspiracists who insist on making a big deal by excluding the Penthouse collapses to "prove" it was a "controlled demolition" by making the collapse time conform to a "supposed" free-fall time.

Nothing like holding contradictory positions at the same!

Originally posted by jthomas

Actually, it's 9/11 conspiracists who insist on making a big deal by excluding the Penthouse collapses to "prove" it was a "controlled demolition" by making the collapse time conform to a "supposed" free-fall time.

Nothing like holding contradictory positions at the same!

Could you please explain exactly what pertinence any penthouses had? Aren't penthouses part of buildings but certainly, by far, not the complete buildings?

Originally posted by OrionStars

All you have to do is demonstrate that the top portion of WTC 2 was leaning 23 degrees for around 15 minutes instead of tilting seconds before global collapse as all the pictures and videos show.

It's a straight forward, simple request.

I will ask this once again. What part of - there do not seem to be any videos available 15 to 23 minutes long showing the south tower lean starting at 9:36 am - isn't clear to you yet? Why don't you explain how anyone can show you anything that isn't available? I, for one, would enjoy knowing how someone accomplishes that impossible feat.

Then all you have to is to admit what we all know. There are numerous videos, some just the raw, unedited videos, of WTC 2 from before it was hit by Arab-hijacked UA 175 until it collapsed. None of them show the top portion of WTC 2 leaning a full 23 degrees for a full 15 minutes before global collapse. You do agree with that statement of fact, don't you?

I am perfectly happy to see your evidence that all those videos and eyewitness accounts must be fake.

Cheers.

Originally posted by OrionStars

Originally posted by jthomas

Actually, it's 9/11 conspiracists who insist on making a big deal by excluding the Penthouse collapses to "prove" it was a "controlled demolition" by making the collapse time conform to a "supposed" free-fall time.

Nothing like holding contradictory positions at the same!

Could you please explain exactly what pertinence any penthouses had? Aren't penthouses part of buildings but certainly, by far, not the complete buildings?

It makes the collapse time around 14 seconds.

Originally posted by jthomas
Actually, it's 9/11 conspiracists who insist on making a big deal by excluding the Penthouse collapses to "prove" it was a "controlled demolition" by making the collapse time conform to a "supposed" free-fall time...Nothing like holding contradictory positions at the same!

That's not true, I only see de-bunkers going on about collapse times, those of us who know better know it makes no difference...;

The free-fall reference actually came from NIST and the times THEY quoted.

NIST estimated the elapsed times for the first exterior panels to strike the ground after the collapse initiated in each of the towers to be approximately 11 seconds for WTC 1 and approximately 9 seconds for WTC 2. These elapsed times were based on: (1) precise timing of the initiation of collapse from video evidence, and (2) ground motion (seismic) signals recorded at Palisades, N.Y., that also were precisely time-calibrated for wave transmission times from lower Manhattan (see NCSTAR 1-5A).

Source

Couldn't find NISTs times for 7 but you can see one and two fell 'at near free-fall speed' according to NIST. Seven fell with no resistance as did one and two, it doesn't matter if it's exactly free-fall, the difference between what it did fall in and what it should have globally collapsed in, remember resistance, should be measured in minutes, or even hours, not seconds. That is if it globally collapsed at all, which imo it shouldn't have done.
None of the buildings should have collapsed globally.

So why is that contradictory? Please explain.

(Edited to add source link)

[edit on 16/12/2007 by ANOK]

Originally posted by ANOK

Originally posted by jthomas
Actually, it's 9/11 conspiracists who insist on making a big deal by excluding the Penthouse collapses to "prove" it was a "controlled demolition" by making the collapse time conform to a "supposed" free-fall time...Nothing like holding contradictory positions at the same!

That's not true, I only see de-bunkers going on about collapse times, those of us who know better know it makes no difference...;

Well, all I can suggest is get out and read more about what 9/11 Truthers claim.

The free-fall reference actually came from NIST and the times THEY quoted.

NIST estimated the elapsed times for the first exterior panels to strike the ground after the collapse initiated in each of the towers to be approximately 11 seconds for WTC 1 and approximately 9 seconds for WTC 2. These elapsed times were based on: (1) precise timing of the initiation of collapse from video evidence, and (2) ground motion (seismic) signals recorded at Palisades, N.Y., that also were precisely time-calibrated for wave transmission times from lower Manhattan (see NCSTAR 1-5A).

Source

Yes, exterior panels, the same ones seen on the video I've posted here numerous times showing it took around 14 seconds for WTC 2 to collapse.

Here it is again. Count the seconds. Note the exterior panels that were falling free from the building are ahead of the collapse front of WTC 2:

youtube.com...

Couldn't find NISTs times for 7 but you can see one and two fell 'at near free-fall speed' according to NIST.

I just showed you your confusion between the building and exterior panels.

Seven fell with no resistance as did one and two, it doesn't matter if it's exactly free-fall, the difference between what it did fall in and what it should have globally collapsed in, remember resistance, should be measured in minutes, or even hours, not seconds.

First, the collapse of WTC 7 included the collapses of the penthouses into the building. One may not exclude them from the collapse time no matter how the collapse occurred.

Second, as a result of the collapse initiation that caused the penthouses to collapse, resistance was removed before the outer walls gave way.

Third, wherever did you get your claim that the collapse "should have" taken minutes or hours? How could you make such a claim when gravity is always the dominant factor in any building collapse, natural or by demolition?!

If the 9/11 tragedy was proven and the government did it intentionally how would we go about justice? I feel the government will never let this happen. There's strawman versions for both sides. If it was proven that it was terrorist would it change the minds of the ones who believe it was intentionally? I very much doubt it myself. All I'm trying to say is that it's to late. Time has passed and the 9/11 commission has spoken. I feel in my own opinion that all we can do now is speculate and discuss the issues of 9/11. Nothing else can be done.

Originally posted by jthomasHere it is again. Count the seconds.

And again I am not questioning your findings as far as times go, I was just pointing out where the 'free-fall' claim came from which was NIST, not 'truthers'.

AFAIK, as I keep pointing out, is even YOUR times are too slow, they may as well be free-fall, it makes NO difference.

Second, as a result of the collapse initiation that caused the penthouses to collapse, resistance was removed before the outer walls gave way.

Huh? What caused the penthouse to collapse, a-symmetrical damage and sporadic office fires? Sry but no matter how you or NIST try to spin it that is not going to happen the way you want it to. It doesn't even make sense.
Resistance was removed by what? How can the resistance be removed before the outer walls fall? If the resistance is removed the whole building falls instantly, as we see in the videos, what's in question is what removed the resistance? Office fires do not get hot enough to cause steel to fail, I'm not even going to argue this proven fact. Even if it was fire it's not going to instantly and globally fail with the building sitting in its own footprint.
We would have seen at least some localised collapsing first, as in the Madrid building.

Third, wherever did you get your claim that the collapse "should have" taken minutes or hours? How could you make such a claim when gravity is always the dominant factor in any building collapse, natural or by demolition?!

Gravity is the dominant factor? You seem to forget a few other laws of physics that just slightly mess up your little hypothesis. I don't have time now to spell it all out but just think about Newtons 1st 2nd and 3rd laws, conservation of energy, colliding bodies and resistance etc...

Buildings simply don't globally collapse into their own footprints from a-symmetrical damage and sporadic office fires. Whoever told you that they do was lying to you, period. If you can find one that did I'd love to see it. Then add the FACT that it showed a classic controlled demolition 'kink' (The penthouse) as the central columns were pulled ahead of the outer columns, to a cause the building to fall in on itself. Which it did.
What are the odds of that?You know, if it walks like a duck...

A perfect controlled demolition caused by a-symmetrical damage and office fires, wow yeah gravity is some stuff eh? Sry but...

And I don't have time to explain it all, again......

but - here's the deal - it's a mesh structure. It's like taking a tube of chicken wire and trying to make it collapse. The only way it will collapse is in on itself. It won't crumble off to the side (not without some really serious effort on your part), it won't partially cave in... the whole thing comes down if one part comes down - but it takes a lot of effort to bring that one part down..... and everything tries its damnedest to stick together - so it will crumble in its own footprint.

If you are going to start getting all 'physics elaborate' - don't forget to take into account the physics of the building design.

What you're doing is taking the physics equations for lift, thrust, etc - and applying them to an airframe.... then forgetting to incorporate fluid-dynamics (aerodynamics) into your design.

It works on paper. But you build it... and then succeed only in flying it right into the ground.

Originally posted by Aim64C
but it takes a lot of effort to bring that one part down..... and everything tries its damnedest to stick together - so it will crumble in its own footprint.

The WTC Towers didn't fall into their footprints. Most of their masses was sent flying outwards around and outside of the complex. Watch videos and you'll see things flying out in arcs in about all directions. Look at pictures of Ground Zero from before the clean-up started and you'll see how messy the entire area was.

Originally posted by Aim64C
The only way it will collapse is in on itself. It won't crumble off to the side (not without some really serious effort on your part), it won't partially cave in... the whole thing comes down if one part comes down - but it takes a lot of effort to bring that one part down..... and everything tries its damnedest to stick together - so it will crumble in its own footprint.

If this is in reply to my last post I was talking about building 7 which was a different design and had no 'chicken wire'...hehe that's a new way to describe it, totally wrong though...

So anyway as Bsbray explained the towers 1&2 did not fall into their own footprints, only 7 did. Even if they did your explanation as to why that would happen makes no sense, where did you get it from? I mean the structure tries to hold itself together while at the same time crushing itself to the ground? Check your logic please...

Maybe you need to re-think this through?

Originally posted by bsbray11

The WTC Towers didn't fall into their footprints. Most of their masses was sent flying outwards around and outside of the complex. Watch videos and you'll see things flying out in arcs in about all directions. Look at pictures of Ground Zero from before the clean-up started and you'll see how messy the entire area was.

The photos on these websites say differently:

www.plaguepuppy.net...

www.garlicandgrass.org...

If you note, all the debris is surrounding the balnce of what is left of the buildings at all times. That is what does happen when a bulding falls in its own footprint, which can only be accomplished by controlled demolition implosion.

It is normal for debris to look just the way it looked in those photos using controlled demolition implosion. The vacuum from implosion aids in pulling the building in on itself while decompressing out a great deal of debris all the way down.

This is a legal controlled demolition:

www.controlled-demolition.com...

For anyone doubting professionals have involved themselves in refuting the "official" version, this one's for you:

www.ae911truth.org...

"Welcome to Architects & Engineers for 9/11 Truth!

229 architectural and engineering professionals
and 587 other supporters including A/E students
have joined us in demanding of Congress
a truly independent investigation. "

And then there is this:

scitation.aip.org...

"Impact of the Boeing 767 Aircraft into the World Trade Center
J. Engrg. Mech., Volume 131, Issue 10, pp. 1066-1072 (October 2005)

Mohammed R. Karim1 and Michelle S. Hoo Fatt2

1Graduate Student, Dept. of Mechanical Engineering, The Univ. of Akron, Akron, OH 44325-3903. 2Associate Professor, Dept. of Mechanical Engineering, The Univ. of Akron, Akron, OH 44325-3903 (corresponding author). E-mail: [email protected]
(Accepted 1 December 2004)

A numerical simulation of the aircraft impact into the exterior columns of the World Trade Center (WTC) was done using LS-DYNA. For simplification, the fuselage was modeled as a thin-walled cylinder, the wings were modeled as box beams with a fuel pocket, and the engines were represented as rigid cylinders. The exterior columns of the WTC were represented as box beams. Actual masses, material properties and dimensions of the Boeing 767 aircraft and the exterior columns of the WTC were used in this analysis. It was found that about 46% of the initial kinetic energy of the aircraft was used to damage columns. The minimum impact velocity of the aircraft to just penetrate the exterior columns would be 130 m/s. It was also found that a Boeing 767 traveling at top speed would not penetrate exterior columns of the WTC if the columns were thicker than 20 mm.

©2005 ASCE"

Originally posted by OrionStars
If you note, all the debris is surrounding the balnce of what is left of the buildings at all times. That is what does happen when a bulding falls in its own footprint, which can only be accomplished by controlled demolition implosion.

Regardless of the word "implosion," and what you think happened to the towers, it is demonstrably true that most of the debris did not land in the footprints of the buildings.

Simple proof:




See the last perimeter columns outlining the footprints of each fallen tower? If you remember how much mass USED to be sitting on top of those footprints, then it should be immediately obvious that most of that mass is now GONE from there. It was thrown out in all directions as the towers fell, all over the complex and beyond. That is all I am/was pointing out.

Originally posted by ANOK

Second, as a result of the collapse initiation that caused the penthouses to collapse, resistance was removed before the outer walls gave way.

Huh? What caused the penthouse to collapse, a-symmetrical damage and sporadic office fires? Sry but no matter how you or NIST try to spin it that is not going to happen the way you want it to. It doesn't even make sense.
Resistance was removed by what? How can the resistance be removed before the outer walls fall?

You don't need NIST nor anyone else to see that the penthouses collapsed before the rest of the structure. Obviously, interior beams supporting those penthouses gave way first. What is so confusing about that?

Third, wherever did you get your claim that the collapse "should have" taken minutes or hours? How could you make such a claim when gravity is always the dominant factor in any building collapse, natural or by demolition?!

Gravity is the dominant factor? You seem to forget a few other laws of physics that just slightly mess up your little hypothesis. I don't have time now to spell it all out but just think about Newtons 1st 2nd and 3rd laws, conservation of energy, colliding bodies and resistance etc...

If I've forgotten something, I'd sure to curious to see just what. Please explain why the collapse "should have" taken minutes or hours? It's your claim.

Buildings simply don't globally collapse into their own footprints from a-symmetrical damage and sporadic office fires. Whoever told you that they do was lying to you, period. If you can find one that did I'd love to see it.

You presume to know how WTC "should have" collapsed, too? Please explain your expertise in this matter of give us the sources of your claims.

It's time for you to provide hard evidence, not more claims.

Thanks.

Cheers.

Originally posted by OrionStars

I have clearly stated it 5 times already. There are no available videos running 23 minutes from 9:36 am per witness testimony from the 106th floor of South Tower until 9:59 am collapse.

You haven't answered my question yet. I repeat:

"There are numerous videos, some just the raw, unedited videos, of WTC 2 from before it was hit by Arab-hijacked UA 175 until it collapsed. None of them show the top portion of WTC 2 leaning a full 23 degrees for a full 15 minutes before global collapse. You do agree with that statement of fact, don't you?"

Therefore, those videos would confirm or refute your claim. Please support your claim by providing us with one of those videos or concede that you are wrong.

Thank you.

Cheers.

Originally posted by jthomas

Originally posted by OrionStars

I have clearly stated it 5 times already. There are no available videos running 23 minutes from 9:36 am per witness testimony from the 106th floor of South Tower until 9:59 am collapse.

You haven't answered my question yet. I repeat:

"There are numerous videos, some just the raw, unedited videos, of WTC 2 from before it was hit by Arab-hijacked UA 175 until it collapsed. None of them show the top portion of WTC 2 leaning a full 23 degrees for a full 15 minutes before global collapse. You do agree with that statement of fact, don't you?"

Therefore, those videos would confirm or refute your claim. Please support your claim by providing us with one of those videos or concede that you are wrong.

Anyone will tell you that the top section was not leaning At all before the collapse started. You can look at any evidence online yourself, i dont know why you want someone to disprove something that is obviously false from the outset. Just watch any video of the towers before they started to collapse, they were standing upright. Who ever said that was mistaken, the buildings were pretty much motionless until they started to collapse.

Originally posted by jthomas
You don't need NIST nor anyone else to see that the penthouses collapsed before the rest of the structure. Obviously, interior beams supporting those penthouses gave way first. What is so confusing about that?

Whats so confusing about that? i'll tell you, that is not how solid steel works, never has, never will. It looks as if you are modelling the building with molten liquid steel, but i can assure you the people who made the twin towers would have certainly used solid steel. Please explain how over 40 interlinked solid steel supports, running from the top of the building to the bottom, connected with hundreds of parralel steel girders can 'give way'. You have been demanding evidence for odd claims for many posts, maybe it is time you gave your own account of how the towers actually collapsed and provide some evidence yourself.

[edit on 17-12-2007 by ZeuZZ]

Originally posted by ZeuZZ

Anyone will tell you that the top section was not leaning At all before the collapse started.

Of course. You mean to be addressing OrionStars, not me.

Originally posted by jthomas
You don't need NIST nor anyone else to see that the penthouses collapsed before the rest of the structure. Obviously, interior beams supporting those penthouses gave way first. What is so confusing about that?

Whats so confusing about that? i'll tell you, that is not how solid steel works, never has, never will. It looks as if you are modelling the building with molten liquid steel, but i can assure you the people who made the twin towers would have certainly used solid steel.

So are you joining those who claim to know how WTC 7 "should have" collapsed? And your source for knowledge is from whom?

Please explain how over 40 interlinked solid steel supports, running from the top of the building to the bottom, connected with hundreds of parralel steel girders can 'give way'.

You just indicated that you know how steel works. I'm assuming you can give me an explanation. Why do we need NIST or structural engineers to be still working on the issue?

You have been demanding evidence for odd claims for many posts, maybe it is time you gave your own account of how the towers actually collapsed and provide some evidence yourself.

I am not one claiming to know - you are. We all observed the same thing. First, one penthouse collapsed, seconds later the other penthouse collapsed, then the entire structure collapsed. You're the one claiming "that is not how solid steel works, never has, never will." I'm asking you to back up your claims with evidence. I'm a skeptic. I ask questions. I want the facts.

Cheers.

Originally posted by ZeuZZ

Anyone will tell you that the top section was not leaning At all before the collapse started. You can look at any evidence online yourself, i dont know why you want someone to disprove something that is obviously false from the outset. Just watch any video of the towers before they started to collapse, they were standing upright. Who ever said that was mistaken, the buildings were pretty much motionless until they started to collapse.

With all due respect, yes it was.

911research.wtc7.net...

What is not available is how long it remained on a 23 degree rift. Therefore, I found witness testimony giving possible time it started to lean. The witness is stated to have been on the 106th floor of the South Tower at the time it rifted. He stated there was a collapse and metal bending and then shift. That was at at 9:36 am, and collapse took place at 9:59 am.

I stated witness testimony placed the initial rift at 9:36 am which meant the top had to be at an angle (23 degrees on a still photo has been measured by myself and others) for at least 15 minutes. Unfortunately, what is available is not 23 minutes long for original rift to collapse to prove it.

What jbthomas has been relentlessly and unreasonably hounding for is 23 minutes of video of the South Tower to prove it rifted at 9:36 am as a witness claimed, and for the sixth time now, I have stated there is not any. I have to go by what the witness said happened at 9:36 am. I repeatedly explained that to no reasonable avail. I have no idea what is not clear in these words, "There is not 23 minutes of video to prove a 23 degree rift for at least 15 minutes". A reasonable person would have accepted that when stated once but not jbthomas.

The top rifted to the outside on the South Tower but not North Tower. There is enough video and photo visual aid to prove that much. We could not have measured an angle, prior to collapse without signs of pending collapse, if the angle had not existed. There was no indication of start of collapse in the still photos I measured for angle. Which means, there is no way other than witness testimony to know when the rift initially took place, to a limit of 23 degrees to the outside, and stated as much six times, including this post.

Originally posted by OrionStars

What jbthomas has been relentlessly and unreasonably hounding for is 23 minutes of video of the South Tower to prove it rifted at 9:36 am as a witness claimed, and for the sixth time now, I have stated there is not any. I have to go by what the witness said happened at 9:36 am. I repeatedly explained that to no reasonable avail. I have no idea what is not clear in these words, "There is not 23 minutes of video to prove a 23 degree rift for at least 15 minutes". A reasonable person would have accepted that when stated once but not jbthomas.

Since I've repeated several times that there is video covering the entire period from before UA 175 hit WTC 2 until it collapsed, why would you insist there is not?

Reasonable people want to know.