Senior Research Scientist Proves that Planes and Fires Caused Collapse

I just came across Frank Greenings paper on the WTC collapse. Here is the PDF file.

www.911myths.com...

In this paper he calculates the energies required and comes to the conclusion that the planes combined with the fires were indeed enough to bring the whole thing down.


Here he addresses the momentum of the floors increasing as it falls.

Because the fractional conversion of energy to heat is even smaller for
subsequent impacts, a rapid self-sustaining total collapse of the towers is an inevitable consequence of first order momentum transfer theory.

Here he addresses the energy required to create the massive amounts of pulverized concrete.

Hence it is theoretically possible for the
WTC collapse events to have crushed more than 90 % of the floor concrete to particles well within the observed particle size range.

It is a fairly long paper and heavy on equations. To be breif here is the conclusions that he came to.

7.0 CONCLUSIONS
- An analysis of the energetics of the WTC collapse events has shown that the kinetic energy of the aircraft collisions and the subsequent gravitational energy released by the descending blocks of floors were quite sufficient to destroy the twin towers in the manner observed. The use of explosive devices in either of the two towers is not necessary to explain the collapse events and is considered to be highly unlikely.

- The times calculated for the collapse of WTC 1 and WTC 2 show good agreement with the observed collapse times verifying the basic assumptions of the momentum transfer model used in the calculations.

- The calculated times represent the minimum theoretical times of building collapse. If shorter times are to be physically achieved they must involve an unknown additional source of energy acting in a downward direction. Such a source of energy does not appear to have been involved in the collapse of the twin towers.

- The kinetic energy of the collapse events was sufficient to crush the WTC floor concrete in both towers to particles 100 m in diameter, or smaller, which is consistent with the observed WTC debris particle size distribution.

- From a consideration of the strength of the WTC columns, and the effective area of support they provided, it is demonstrated that the conditions necessary for the initial floor collapse were initiated by the aircraft impact and made irrevocable by the subsequent eccentric loading of the core columns. It is therefore suggested that the total collapse of both towers would have occurred even without the jet fuel fires.

This is the most in-depth paper I have seen on the collapse addressing the demolition theories, pro or con. I recommend that you read the whole thing before commenting as it is very informative on the actual energies involved in such a collapse.

I'd also like to point out that another paper by Dr. Greenings calls the computer simulations of NIST inaccurate. While his own numbers support a gravity driven collapse he also has serious problems with the NIST report.

www.911myths.com...

Clearly, if NIST’s computer model is essentially correct, the Twin Towers collapsed (or fell over!) at ridiculously small downward displacements and tilt angles, and were inherently unstable as soon as they were struck by aircraft. This raises serious questions about the design and construction of the Twin Towers. However, a more reasonable assessment would be that NIST’s computer model is highly inaccurate, and therefore of no value in explaining the demise of the Twin Towers.

[edit on 29-1-2006 by LeftBehind]

I find it interesting how two people can look at the exact same data, and come to two such radically different conclusions. On the one hand you have Steve Jones who says that they HAD to have been brought down by explosives. On the other hand you have Frank Greenings, who says they WEREN'T brought down by explosives. It should be interesting to see the debate on this one, and eventually to find out who was right.

Dr Greening has also authored a paper showing that thermite was in fact in the buildings.

www.911myths.com...

The chemistry of molten aluminum has also been reviewed and the corrosive and highly reactive nature of this material highlighted. It is shown that molten aluminum readily undergoes violent explosive thermite reactions when dropped into slurries of lime, gypsum or rust – materials that were present in great abundance in the impact zones of WTC 1 & 2, a place where fires raged and aluminum was being heated above its 550 C
melting point on the morning of 9-11.

So the thermite claims could indeed be true. In this case however it occured in the building and was not covertly planted with other explosive device.

Okay, I'm starting to get confused here. First the planes brought the buildings down, then they didn't, now they did. A plane hit the pentagon, then it didn't, then it did, then it didn't. The planes were remote controlled, they were flown by terrorists, they were holographic images designed to cover up missles. All the terrorists bodies were accounted for, but not on the list and showed up in Europe months later.

Can someone please point me to a corner I can sit in and rock back and forth until it all goes away?

Seriously though, I agree with Zaphod. This paper in itself isn't terribly interesting to me, but I'm waiting to see what starts to hit the fan once everyone starts to pay attention to it.

greening's entire conclusion is rendered moot because he used incorrect variables.

he used a total mass of 500,000,000Kg which is unsupported and incorrect.

here is an explanation from a physics student that i know:

Dr. Greenings paper did provide a scientific look into the collapse of the buildings by providing detailed calculations and referenceces. However here's where he went wrong....Those of you that may not understand chemistry nor physics or math for that matter would take his word as bond due to his qualifications. And that is normal as this is the man's life and it is what he does. However having carefully looked over his paper on the collapses, I noticed a fundemental flaw...He made a major assumtion that bascially ended up with missrepresented results.

Searching for the actual values of the twin tower masses, you'll get 500, 000, 000Kg from many sites. However, none of these sites tell you where this figure was taken from. If you were to read the 2002 fema and nist reports, you would get 200, 000, 000kg for each tower. So I ask the question...where does Greening and others that support his position get this figure from?

Before i go into the more acurate figures I wanna point something out to each of you. There are buildings taller than wtc....made of concrete and steel that do not even weigh in 500, 000 tonnes.


Empire State Building, NYC = 365, 000, 000 kg


Woolworth Building, NYC = 223, 000, 000 kg


John Hancock Tower, Chicago = 384, 000, 000 kg


Sears Tower Chicago = 440, 000, 000 kg.


Taipei 101 = 700, 000, 000 kg.


Petronas Twin Towers = 350, 000, 000 kg. (each)

Both twin towers were built to be as light yet rigid as possible so as to withstand the extreme forces of the 100 + mphs. The buildings load was carried 60% by it's core and 40% by it's perimiter steel columns. The perimiter carried the lateral load to resist the wind whereas the core carried the gravity load.


Now check this....the weight of structural steel used in each Tower is generally reported to be 96, 000, 000 kg and the weight of concrete is said to be 48, 000, 000 kg per Tower.

The Aluminium panels were reported at 2 million kg

The wallboards were at 8 million kg


Adding those together the skeletal structure clocked in at 154 million kg per tower.


More mass is added to the figure when you factor in the utilities, and other fixtures.


Because there is no actual report that fema nor nist gave for these figures the only thing we can really do is take a guess at it.

Plumbing, electrical and telecom would each add about 5 million kg giving us additional 15 million kg. Adding that to our structure we get a figure of 169 million kg which constitutes as the buildings dead load.


When we populate the buildign with office furniture, supplies and people then more mass is added.

As you can see this 169 million is only a 1/3 of the reported total weight of the building. Factoring the live load of people, office furniture and other objects in the buildings...the live load will rise dramatically and the building could top out to over 300 million kg. but it's still 200 million shy of the 500 million.

The sears tower was larger and taller than either tower and it is also a tube within a tube steel building yet it weighs less?

John Hancock is 100 stories and is built as tube within a tube just like the twin towers composing, of steel, aluminium and glass, yet it clocks in at 384, 000, 000kg. (live load included). And the building was not built of light weight steel like the twin towers so it was in fact heavier.

WTC is similar to John Hancock in terms of it's concept so it's fair to consider the two buildigns will be close in mass value. In any mathematicaly equation if one variable is off by just a mere fraction this throws ur result off. Greening was off by 200 million kgs....so his values for the k.e. and g.p.e. would undoubtedly give us those high values with such a large mass.

What upsets me guys is not enough detailed information on the towers construction is widely distributed....and the only figures we can really work from are fema and nist....bc the buildings plans and structural elements are deamed national security. If they have nothing to hide then why cacn't independent scientists get copies of the buildings designs? They are already destroyed and they won't be used again so why the secrecy?

we emailed this to dr. greening and here was his reply:

"You make some very good points and I will try to address them as best I can. First let me say that the article you are quoting was written a while back and I have done some other stuff since then that adds and expands on my original work. That original work was therefore a first attempt to see if the Towers could theoretically have fallen by a pancake collapse. The answer appeared to be YES! But as I looked at more videos and read some of the stuff I am sure you have also read, I now say that the collapse of both Towers was more complex than my simple model, as I will explain in a moment. First, on the mass of the Twin Towers, I have recently done some checking into that and I see quite a spread in values.... Some references simply give the potential energy, which implies a mass through the equation 1/2Mgh, (factor of 1/2 because average height fallen is h/2)...... For example, FEMA give the PE of one Tower as 4 x 10^11 J which implies a mass of 196, 000, 000 kg, but the May 2002 issue of Civil Engineering Magazine to be found at ASCE.ORG gives the PE as 3 x 10^12 J implying a mass of 1, 472, 000, 000 kg! The figure I used, and I think it was similar to the value quoted by Profs Eager, Bazant and Kausel ( all engineering profs who have written articles on 9-11) is somewhere between the FEMA and the ASCE.ORG number, let's say about 500, 000, 000 kg....... But I would really like to see a detailed breakdown of the mass, because I am not sure if any of these numbers are correct!"

so he admits the most important variable he uses in his paper could be incorrect and admits that his source is "other reaserchers" who happen to be the most prominent official story hacks whose "pancake" and "truss" theories have been shown to be absurd.

not only that but he starts his response by minimizing the results of this paper because it's "old".

so of course his new concept of "natural" thermite reactions causing a "natural" controlled demolition is meant to help save himself from his initial conclusions that apparently he even believes to be false!

Originally posted by Lyte Trizzle


so of course his new concept of "natural" thermite reactions causing a "natural" controlled demolition is meant to help save himself from his initial conclusions that apparently he even believes to be false!

WOW! How did you figure that out! Are you a mind-reader or a channeler or something like that?

That's a totally awesome skill you have there.

See, this is why we're having a bit of problem here. Anybody that says something you don't agree with you try to totally discount their voice by pulling a rabbit-outcha-butt.

That won't work here, Trizzle.

It won't work. You can't go about making baseless claims against people just because their theory doesn't match yours.

We don't do that here.

[edit on 1-29-2006 by Valhall]

And as a follow-up, and this is a very serious enquiry did your "physics student" take the time to also re-run the calculations done by Dr. Greening?

It appears to be, according your expert - the "physics student" - we're sitting at 300,000,000 kg, so, the equations are there...please, tell us how much the analysis changed. (Hint - I'm betting there's not a single equation with anything other than a first-order mass used in it). Quick, you can use your TI on this one!

There's a really serious and important reason I want your "physics student" expert to come back and give the changes to the final numbers on this for me - beins I'm just a poster on a discussion board.

There's some other numbers I'd like to check your expert "physic student's" nubmers against.

Originally posted by Valhall
See, this is why we're having a bit of problem here. Anybody that says something you don't agree with you try to totally discount their voice by pulling a rabbit-outcha-butt.

That won't work here, Trizzle.

It won't work. You can't go about making baseless claims against people just because their theory doesn't match yours.

We don't do that here.

oh but you "do" sarcasm just fine.

if this site had any integrity you would be fired as a mod for this blatant hypocritical nonsense.

seems like YOU are the one discounting assertions you don't agree with by calling it "trolling" or claiming i pulled it out of my "butt".

out of my butt????

how dare you!!

i not only gave specifics as to why greening's conclusions were incorrect but i quoted a personal email from greeninig himself ADMITTING IT when we confronted him!!!

"First let me say that the article you are quoting was written a while back and I have done some other stuff since then that adds and expands on my original work. That original work was therefore a first attempt to see if the Towers could theoretically have fallen by a pancake collapse. The answer appeared to be YES! Butas I looked at more videos and read some of the stuff I am sure you have also read, I now say that the collapse of both Towers was more complex than my simple model, as I will explain in a moment. First, on the mass of the Twin Towers, I have recently done some checking into that and I see quite a spread in values.... Some references simply give the potential energy"

do you understand what he is saying?

he is admitting that his initial conclusions were based on incorrect variables but instead of going back and revising or correcting the variables......

he has merely come up with antoher theory to "add" or "expand" on his incorrect one!!

this is what dr greening himself told us.

i didn't pull it out of my "butt".

you owe me an apology.

Yes! I said OUTCHA-BUTT!

You just accused this professor of LYING...With no evidence! OUTCHA-BUTT!

That's what I call that.

Can you please provide me the new numbers for the analysis with your "expert's" numbers? This is very important. I have some numbers I would like to check now that I have an expert that can help me.

[edit on 1-29-2006 by Valhall]

I'm not going to go through all of that point by point, but I'll outline the major flaws. It makes a lot of the same faulty assumptions that NIST does, and thus, no new ground is really covered here.

A quick skim will show that the paper is obviously geared around justifying the official story, much in the same way that the NIST Report was.

For examples,

Page 5 of the paper says,

We note in concluding this Section that the values for tc given above represent the calculated values for the time of collapse of the WTC towers neglecting the energy required to crush or otherwise destroy the support structure of each floor. This energy, which we will call E1, is considered in detail in Section 4.2. For now it is sufficient to note that the collapse times calculated without allowing for E1 are already in reasonable agreement with the observed collapse times. This suggests that E1 is relatively small compared to the kinetic energy associated with the falling blocks of floors;

So, in other words:

The time it would've taken for the floors to fall with no resistance is already approaching the total amount of time it took the towers to fall, so then they assume that, therefore, there was not much resistance from the structure! Now, that's bias at best. At worst, they're doing something pretty much equivalent to lying outright, if not worse.

When the time it would've taken the building to fall without resistance (which is something that WCIP has already figured up in a past thread and nothing new anyway) is already about the total collapse time, that's bad for you guys. It means they're assuming that all that steel and concrete and etc. just gave way really easily without really slowing down the collapse of 13 floors (for WTC1). And they're putting on in this paper as if that can be expected, simply beacuse the collapses, without resistance, already took a long assed time in relation to the actual collapse times.

And the following conclusion, reached on page 8, is totally disconnected from the reality of the event:

A comparison of these Q values with the initial kinetic energies, Ti (WTC 1) and Ti (WTC 2), shows that a relatively small fraction of the available energy, (6.7 % for WTC 1 and 3.3 % for WTC 2), is converted to heat by the first impact of the upper blocks of floors. Because the fractional conversion of energy to heat is even smaller for subsequent impacts, a rapid self-sustaining total collapse of the towers is an inevitable consequence of first order momentum transfer theory.

Note that this is their explanation to the towers being able to continue falling the whole time.

Four problems with this that make it irrelevant, and wrong (just as this conclusion has ALWAYS been wrong, and always will be unless you guys come up with something better):

1. The impacted floors did not remain intact and become additional driving weight for the collapsing "blocks." They were destroyed and ejected outwards, with an average of around 80% of the mass of each floor being ejected outwards radially and thus not adding on to the mass of falling materials at all.
   
2. The "blocks" of falling floors broke up and lost their integrities during the collapses, with large chunks falling over the side at various times somewhat early in the collapses.
   
3. Because of the above points A and B, it can be assumed, by their own reasoning, that the relative amount of energy lost to heat through each impacting of a floor would be an increasingly large fraction of the total energy available – NOT AN INCREASINGLY SMALL ONE.
   
4. The collapse speed did not slow, immediately indicating that (1) absolutely no resistance from the structure, or that (2) explosives (third source of energy) were used to blow out each floor.

So the math these guys are presenting is totally unrealistic and assuming things that did not happen, or leaving out things that did.

Sorry, LeftBehind.

Other more minor, but nonetheless wrong/misleading, points:

From page 3,

For the general case of n floors collapsing we define a collapsing mass Mc :

Mc = n mf ……………………. (1)

where mf is the mass of one WTC floor, assumed to be 1/110 the mass of an entire WTC tower, namely mf = (510,000,000 / 110) kg  4,636,000 kg

This neglects the fact the higher floors became increasingly lighter. No mention of this is made.

Page 16,

"Revised collapse times":

We have re-calculated the descent velocity after the impacts on every floor and determined a revised collapse time that now includes the effects of the energy lost in crushing the support structures.

So now they're going to figure out how much energy would've been lost in destroying all the steel perimeter columns and core columns and trusses, and the concrete, and etc.



A lot more energy exerted to destroy all of those things so thoroughly, into so many small pieces, you would think, in comparison to just falling straight down to the Earth without resistance. It would take a lot of energy away from the actual falling.

Previously (E1 = 0) tc = 12.6 sec

Revised (E1 = 0.6  109 J) tc = 12.8 sec

Yeah, that's right. 0.2 seconds.

An additional 0.2 seconds of WTC1 collapsing was all that was required to actually destroy the buildings, ejecting busted-up material everywhere, radially, out from the footprint. That's a snap of a finger!! And concrete being pulverized into dust while the trusses to hold them in place were having their bolts sheered? And for WTC2, the additional time was apparently half that: 0.1 seconds to destroy all of the steel, concrete, etc., to the state that it was observed in after the collapses. All the while energy is supposedly being lost on each floor, even as they maintain the same velocity? Why do you believe this?


The graph on page 16 suggests that the amount of available energy decreased significantly as the collapse progressed onto thicker columns, and yet in reality no such change in energy was observed.


The graph on page 17 is based upon the flawed reasoning outlined above, that the floors would accumulate and that no mass was lost, etc.


From page 19,

The smoky appearance of the jet fuel fires suggests that the flames
inside each tower were fuel-rich and therefore probably below 850° C.

First let's look at how this guy got "fuel rich." The smoke turned back. That means there was soot, uncombusted hydrocarbons, in the smoke. That means that the fire wasn't combusting all of the hydrocarbons at its disposal, and thus inefficient. This can stem from two things, essentially: too much fuel, or a dying fire. The fires immediately after impact were lighter and then turned black and the jet fuel was burned away, with the plastics and other office supplies being there the whole time. Thus, it logically follows that the fires were not producing black smoke because of a sudden abundance of fuel, but because they were dying.

Now, this does suggest lower temperatures than 850° C, but lower than the author of the paper is going to admit.

From the same page,

In addition, the structural steel was heated indirectly and almost certainly never attained a temperature above 600° C. Nevertheless, some (~ 20 %) loss of strength is to be expected for steel heated to 550° C, a temperature that may have been reached by some WTC core columns.

From information released on the structural integrity of the WTC's core and perimeter columns that this fellow apparently missed, the amount of integrity loss from fire had to have been around 60%. Not 20%. 20% would not cause a floor to fail, quite simply, even when added to the perimeter and core impact damage of less than 13% in either tower (perimeter columns within themselves suffered 13% or less loss in the region, and core columns logically less in percentage given the circumstances, so proportionally averaged together you still get less than 13% in either tower).

From page 20,

The safety factor for collapse of the 80th floor is now only a little over two, but apparently still sufficient to sustain the building almost indefinitely. However, the damage to the twin towers was asymmetric so that the post-impact gravity load above the impacted floor was no longer uniformly distributed.

The obvious problem here is that the buildings did not fall asymmetrically. The buildings tilted some prior to vertical collapse, especially WTC2, but this has physics problems unto itself indicating the the top floors were not using the bottom floors as a fulcrum; there was no connection. WTC1 didn't even have that much going for it when it collapsed, pretty much perfectly symmetrical from the get-go.

Conclusions, page 21,

An analysis of the energetics of the WTC collapse events has shown that the kinetic energy of the aircraft collisions and the subsequent gravitational energy released by the descending blocks of floors were quite sufficient to destroy the twin towers in the manner observed.

Flaws in the reasoning and calculations leading to this conclusion have already been exploited. In addition, the charts they show blatantly ignore the fact that there was no observed loss of energy in either of the WTC collapses.

The times calculated for the collapse of WTC 1 and WTC 2 show good agreement with the observed collapse times verifying the basic assumptions of the momentum transfer model used in the calculations.

As has also been shown, this conclusion was reached after it was assumed that, since unresisted collapses already took up the vast majority of the available time, the resistance *must have* taken very little time. This type of reasoning totally undermines the "possibility" of the resistance greatly affecting collapse times, and is intellectually dishonest to say the least.

The calculated times represent the minimum theoretical times of building collapse. If shorter times are to be physically achieved they must involve an unknown additional source of energy acting in a downward direction. Such a source of energy does not appear to have been involved in the collapse of the twin towers.

Such a source would certainly not appear if one were to constantly look the other way when faced with its probability. At any rate, this conclusion seems to me as if the author is encouraging others to show the collapse times were less than his figures in order to debunk him, when really his whole reasoning on the times he gives is extremely off. A sort of straw man is presented here.

The kinetic energy of the collapse events was sufficient to crush the WTC floor concrete in both towers to particles 100 m in diameter, or smaller, which is consistent with the observed WTC debris particle size distribution.

Without even going into the energy problems with this (which are similar to the energy problems of the rest of the collapse), it's illogical for the concrete to have been so thoroughly crushed to begin with when the trusses holding them in place were having their connecting bolts rapidly sheered off.

From a consideration of the strength of the WTC columns, and the effective area of support they provided, it is demonstrated that the conditions necessary for the initial floor collapse were initiated by the aircraft impact and made irrevocable by the subsequent eccentric loading of the core columns. It is therefore suggested that the total collapse of both towers would have occurred even without the jet fuel fires.

Immediately obvious question: then why did they not fall immediately after impact?

But besides that, in the section where this conclusion is built up and outlined, we come across the following:

Now consider the 80th floor of WTC 2 after the aircraft impact. About 20 % of the support columns have been destroyed and another 10 % may have been buckled to some degree.

This is borderline lying. Firstly, "the support columns" are not further identified as perimeter or core. Secondly, the only available numbers are for the perimeter columns. Those figures are not "[a]bout 20%," but less than 13% in either building as per FEMA. I'm not even sure what figures are being referenced when the author states "another 10 % may have been buckled...", and there are no figures whatsoever for the core columns, of which it's very likely that even less were knocked out in ratio than the perimeter columns.

The author subsequently goes on a theoretical, unsupported journey of imagination as to how the core columns *may* have failed so as to allow collapse that not even NIST will approach. There is one truth to this, though: the fires certainly had nothing to do with the failures.

That covers the bulk of the b.s. presented in that paper. Simply put, it doesn't take everything it needs to into consideration, but looks the other way here and there and makes false assumptions, etc. to get to the desired result, just as the NIST Report does.

Originally posted by Valhall
And as a follow-up, and this is a very serious enquiry did your "physics student" take the time to also re-run the calculations done by Dr. Greening?

It appears to be, according your expert - the "physics student" - we're sitting at 300,000,000 kg, so, the equations are there...please, tell us how much the analysis changed. (Hint - I'm betting there's not a single equation with anything other than a first-order mass used in it). Quick, you can use your TI on this one!

There's a really serious and important reason I want your "physics student" expert to come back and give the changes to the final numbers on this for me - beins I'm just a poster on a discussion board.

There's some other numbers I'd like to check your expert "physic student's" nubmers against.

why doesn't greening do it?

he admitted he didn't use an official source and didn't even stand by his OWN conclusions.

the analysis is moot because it used incorrect variables.

to ask if the equations hold true "anyway" is not a scientific approach and shows your lack of understanding in this regard.

changing the variables even a tiny bit can have a DRASTIC affect on the results.

and that variable is waaaaaaaaaaaay off.


and another important fact that greening left out is that the steel gets progressively narrower and less dense as you travel up the building. B
basically the top 20 floors are much lighter than the 20 floors below it. the calculation he gave assumes the building's steel skeleton is contstant from ground to roof.

greening distanced himself from his own conclusions and admitted that this extremely important variable is likely incorrect when we pointed it out.

if you want to claim his theory holds true even though he hasn't.....you can go do the calculations yourself.


[edit on 29-1-2006 by Lyte Trizzle]

Originally posted by Valhall
You can't go about making baseless claims against people just because their theory doesn't match yours.

We don't do that here.

Howard does that here.

Have you not seen his thread on Steven Jones?

But, that's ok, right? Because Howard's on your side? After all, that thread's 3 pages long, and I never saw a single complaint from any mod or etc. on that thread.

Originally posted by Valhall
Yes! I said OUTCHA-BUTT!

You just accused this professor of LYING...With no evidence! OUTCHA-BUTT!

That's what I call that.

Can you please provide me the new numbers for the analysis with your "expert's" numbers? This is very important. I have some numbers I would like to check now that I have an expert that can help me.

once again YOU are the one lying.

i NEVER claimed that he lied.

i claimed he was incorrect and was trying to save himself by "adding" to his theory just as he TOLD US DIRECTLY IN EMAIL!

and you lied again by quoting me calling my friend an "expert" when i called him a "student".

of course this "student" was correct as dr. greening himself admitted.

nothing else is required from my student friend in this regard.

and you consistently falsely accusing me of doing things on this board and using a sarcastic tone is out of line.

No! It's not okay bsbray...and you know you're one of my favorite members (along with billybob) to argue with on these issues, so

lol

This is very important, so don't brush me off. I need Lyte Trizzle's expert to re-run the equations with the lower mass, because it will EXTEND the time to collapse on the Tower. I see that Dr. Greening has calculated (erroneously but that's been caught due to Lyte Trizzle's expert! THANK GAWD) that WTC 1 fell in just under 13 seconds.

Well, the change in mass is going to cause all of the impact energy equations to be lessened, and with the big ol' acceleration due to gravity equation being dependent on mg - well, that's lessened. So I want to know how long the time to collapse is extended.

Because in this post...

www.abovetopsecret.com...

which I repeat my calculations here...

**********

Check my math:

g = 32.2 ft/s^2



So about 9 seconds with no drag, no resistance. But, of course, there was resistance. And there's proof the building fell at just about the rate you'd figure as the top portion plowed through the floors below it.

In this footage, in 10 seconds the top of WTC1 has just fallen to the height of the Woolworth Building which is the pointy-topped roof just about in the center of the shot. The Woolworth Building stands 792 feet tall. This means that the top portion of the building had only fallen about 500 feet in 10 seconds. Backing out the acceleration:

a = (2/t^2)*x and using t = 10 seconds, x = 500 feet

we get right at 10.1 - 10.2 ft/s^2. But why rely on one data point?

In this footage we see 23 seconds of collapse. But if you watch the spire at the top of the building...it emerges from the still falling debris cloud and no longer exhibits downward motion. That timetag on this video is 18 seconds.

If we stick with the 10.1 - 10.2 ft/s^2 acceleration we come up with:



That's too close to argue about.

*****************************

I show that WTC 1 took 18 seconds to fall.

Now, I respectfully request that Lyte Tizzy's expert review the equations with the lowered mass of 300,000,000 kg for each tower and tell me how much it extends the collapse time so that I can verify my work.

A member of the TRUTH MOVEMENT surely couldn't have a problem with that, now could they?

Originally posted by bsbray11

Originally posted by Valhall
You can't go about making baseless claims against people just because their theory doesn't match yours.

We don't do that here.

Howard does that here.

Have you not seen his thread on Steven Jones?

But, that's ok, right? Because Howard's on your side? After all, that thread's 3 pages long, and I never saw a single complaint from any mod or etc. on that thread.

exactly.

except that I did NOT do that.

i cited an email from dr greening himself.

if you don't believe me.....email him and ask him if those are his words.

No you did do it. My comments weren't about the mistake in the estimation of the tower mass. My comments were toward this

so of course his new concept of "natural" thermite reactions causing a "natural" controlled demolition is meant to help save himself from his initial conclusions that apparently he even believes to be false!

And that's accusing the man of lying and pulling a rabbit outcha butt.

Hey! Are you going to get your expert to run those numbers? So that we can either validate or invalidate my estimates on WTC 1's collapse time?



[edit on 1-29-2006 by Valhall]

What can we possibly solve with the collapse time figures?

The Twin Towers did not fall at free fall. This is shown, and can be easily shown, but then what we need is how long they would have fallen if there were no explosives, but just steel on steel, 13 floors vs. 97. There's no way for us to know those figures, because we're still arguing over whether or not there were explosives in the building, and making assumptions isn't going to help either argument that hasn't already been proven.

Look at some of the other problems I just pointed out with the paper, that apply to all variations of pancake theories: theoretical changes in implulse vs. visible changes in impulse, as the towers continued to fall.

Originally posted by Valhall


This is very important, so don't brush me off. I need Lyte Trizzle's expert to re-run the equations with the lower mass, because it will EXTEND the time to collapse on the Tower. I see that Dr. Greening has calculated (erroneously but that's been caught due to Lyte Trizzle's expert! THANK GAWD) that WTC 1 fell in just under 13 seconds.

Well, the change in mass is going to cause all of the impact energy equations to be lessened, and with the big ol' acceleration due to gravity equation being dependent on mg - well, that's lessened. So I want to know how long the time to collapse is extended.

Now, I respectfully request that Lyte Tizzy's expert review the equations with the lowered mass of 300,000,000 kg for each tower and tell me how much it extends the collapse time so that I can verify my work.

A member of the TRUTH MOVEMENT surely couldn't have a problem with that, now could they?

now the moderator is calling me names!

my how appropriate.

greening admitted his variables and conclusions are "old" and that he has reconsidered it after further research.

and that he has "added" to it with other theories.

which i find rather suspect.

why would a scientist "add" to a theory built on faulty data?

the speed of collapse was not a focus of greenings paper and free fall speed is the same for objects of any mass.