Correct speed of building collapse

[beachnut]

failed to make a single correct conclusion in 6 years, 9/11 truth (lies)

I think a reasonable range for the actual time is 12-16 seconds. Based on the type of modeling we are doing it would be difficult to claim nefariously assisted collapse with out corroborating evidence. I have seen no convincing explanation of how or why a controlled demolition would have been implemented. However, I have seen no convincing explanation that the plane impact and fires would have caused the collapse to initiate or procede so rapidly.

While I am an electrical engineer, I actually find structural engineering more interesting. I have no pet theories ragarding an inside job, but on the other hand I wouldn't put anything past Bush-Cheney-Rumsfeld Inc. Then again maybe it's a design or contruction related problem. I am interested in doing honest research and analysis and letting the cards fall where they may.

I KNOW the actual time is as seen on 9/11! I also understand impact and fire destroyed the building; because the impact was 10 times greater than design. They had envisioned a slow speed aircraft impact! You say you are an engineer and you do not listen to engineers. The WTC chief structural engineer told everyone the impacts were 7 to 11 times greater than the 187 pounds of TNT impact planned for. You have no idea what you are doing when you fail to learn about the WTC from the person who was in charge of the structure. Instead you support people who post false information and imply pet theories you support by being a member.

You have no pet theories regarding an inside job? OH YES YOU DO! You signed a petition accusing me and others of crimes on 9/11! SEE:

Signatory of Petition of Solidarity to the Attorney General of New York for a new independent grand jury investigation of 9/11 11/19/04: "We the undersigned: a) think that there is ample evidence and probable cause to believe that many grave and still unresolved crimes were committed by US officials prior to, during and after the events of 9/11; b) observe that most of these apparent crimes, including but not limited to abetment of mass murder, criminal negligence, insider trading, and obstruction of justice fall well within the jurisdiction of New York's top law enforcement officials ..." http://www.justicefor911.org.

You do not even research yourself properly.
YOU do have pet theories you just accused BUSH and DICK; Why not throw in PNAC. OOPS, you did throw in PNAC@!!!! You have not pet theories and you have no FACTS! OOPS

According to Richard Clarke, Bush and Rumsfeld conspired to ignore terrorism and focus on PNAC agenda (attack Iraq):

You should look at the collaspe of the full scale model, it was called the WTC towers, you are trying to blame me and others in the US for doing it and you joined this group who does have pet theories of THERMITE, this means you support pet theories of THERMITE. Plus Jones tells lies, he use to say this was proof of thermite!

You support liars who have nut case ideas on 9/11! See on this web page you are a member of , http://stj911.org/members/index.html , Scholars for 9/11 Truth & Justice. This group has lied. This group has no evidence, it is not unusual for you to claim you have no pet theories, and then blame Bush in the next sentence. You implications are fact less, your purpose is clear. I found your info at the web site of peer review woo

Scholars for 9/11 Truth & Justice Member-
Gregory Urich B.S.E.E, BA Music Senior Consultant Software Engineering

Your group cherry picks information and posts errors! This is your group. You belong to a group that essentially makes ups stuff, lies, about 9/11. And you have not pet theories? You joined these groups of 9/11 truth who are liars and they spread false information. I hate to tell you, but joining these groups is putting the cart before the horse. I think you may have some political biases guiding your scientific method? By not doing the research and finding the facts you are making fun of those who died on 9/11. Proof is your joining groups who spread false information about 9/11 and then claiming you have no pet theories! FALSE information flows freely, the only thing you do not have is facts.

The correct speed for the WTC collapse is what we see. The simple models help you understand certain aspects of the collapse. But it is very complex, and simple. One thing the truth movement overlooks are all the work done on the WTC collapse, not just NIST. Plus you ignore the floors. When the tops fell slowly on the lower sections the floors below can not hold the weight.

But please do not make out like you have no agenda; you are worse than what you blame PNAC for! And with you we have proof of signing the petition and your membership in these groups of false information peddlers. But the correct speed is on record, we all saw it on 9/11, you and your groups of false information charlatans have not made any progress in 6 (SIX) years. I mean it is embarrassing, the passengers on flight 93 figured out 9/11 in a few minutes, you "truth engineers" and "scholars" have failed to make a single correct conclusion in 6 years; beat by lay people...

 

[jhunter1163]

Pre-arranged Nefariously Assisted Collapse = PNAC!!!!11!1111!!ELEVENTY!!!

Connect the DOTS, people!

[/truther]

 

[deep]

OOPS You should look at the collaspe of the full scale model, it was called the WTC towers, you are trying to blame me and others in the US for doing it and you joined this group who does have pet theories of THERMITE, this means you support pet theories of THERMITE. Plus Jones tells lies, he use to say this was proof of thermite!

Where is this claim from Steven Jones that he had proof of thermite being used to bring down WTC1/2/7?

Please remember that saying "X is consistent with Y" is not the same as saying "X proves Y". Please also remember that I'm asking you a very specific question which should have a very specific answer. Resist the urge to type eight paragraphs and/or use nine or more exclamation points in your response. Thanks much.

 

[GregoryUrich]

Pre-arranged Nefariously Assisted Collapse = PNAC!!!!11!1111!!ELEVENTY!!!

Connect the DOTS, people!

[/truther]

Chuckle.

 

[beachnut]

Where is this claim from Steven Jones that he had proof of thermite being used to bring down WTC1/2/7?

Please remember that saying "X is consistent with Y" is not the same as saying "X proves Y". Please also remember that I'm asking you a very specific question which should have a very specific answer. Resist the urge to type eight paragraphs and/or use nine or more exclamation points in your response. Thanks much.

You must of missed his earlier papers and presentations. Tell me he does not imply it! In one version of his papes he said this was proof of thermite making the cut, bringing down the WTC. His first paper is sad, you should pay attention, Jones changes the story he made up in 2005 constantly. Your 9/11 truth experts are spreaders of false information and Jones' papers change as he tries to back in the next smoking gun. Gee, this was a smoking gun once, and he still implies it is proof! Learn to read, learn to collect the lies as they can change without notice.

Go ask Jones why this is still in his paper! Why ask me, you seem to be the fact less truther, run along and ask your experts for some more lies.

(Notice especially the uneven cut at the back of the column and the clinging previously-molten metal on both the outside AND the inside of the column, left photo, suggesting this was NOT cut using an oxy-acetylene torch, but rather that a highly exothermic chemical reaction was involved in cutting through this steel column.) JONES PAPER TODAY

Darn, Jones is implying thermite did it! Are you saying thermite was not used in the WTC and Jones is making up lies? He keeps changing his story!

suggesting this was NOT cut using an oxy-acetylene torch, but rather that a highly exothermic chemical reaction

Jones' words not my words. Guess you failed to follow Jones. You are right, this only proves Jones is misleading people, and he has taken out the smoking gun reference he used before. Does this mean he is retracting his lies? Now he is just implying something? I will now define it as a lie since he use to use this as a smoking gun implication for his htermite lie.
Plus he shows a cutter charge to imply the WTC was destroy with RDX cutter charges. But you know, not one cutter charge damaged column was found! Just clean up cuts. Why is Jones making this stuff up? Do you have a clue? You are telling me there was no thermite, Jones says there is smoking gun after smoking gun for thermite but only produces hearsay junk like his paper, in his own journal of 9/11 lies.

Thank you for standing up for Jones, he is a nut on 9/11 and needs all the help he can get. I am pretty sure he is politically motivated to make up false information on 9/11, or he is pure nuts. Take your pick. If you need to see his first paper ask, and you shall receive. If you want to defend him, you must read all of his presentations and papers, each change etc., else you are lost defending lies.

From his the first paper I could find as he wakes up to the nut case ideas in his own head. I love his simple model. Funny stuff. (I believe when he did this paper he had done as much research as Charlie Sheen has on 9/11)

5. I conducted simple experiments on the "pancaking" theory, by dropping cement blocks from approximately 12 feet onto other cement blocks. (The floors in the WTC buildings were about 12 feet apart.) We are supposed to believe, from the pancaking theory, that a concrete floor dropping 12 feet onto another concrete floor will result in PULVERIZED concrete observed during the Towers' collapses! Nonsense! My own experiments, and I welcome you to try this yourself, is that only chips/large chunks of cement flaked off the blocks -- no mass pulverization to approx. 100-micron powder as observed. Explosives, however, can indeed convert concrete to dust --mostly, along with some large chunks-- as observed in the destruction of the Twin Towers on 9-11-01.

You really should study Jones more. I wonder why he wastes time on his thermite theories if he does not think he has the "smoking gun". He has said it, Jones has said he has a smoking gun, I thought it meant proof! Silly little me.

It gets worse. If you can not find the false implications in Jones' work, you maybe lost and doomed to be a 9/11 truth follower.

OOPS, I agree; Jones has zero proof of anything, you are correct Jones has no Proof. !!! I thought you were defending him, you are saying he has no proof. Got it... never mind

Regrettably, Jones is also a truther because of the collapse speed which he calls

combined with Conservation of Momentum considerations gives a much longer time for the fall

He was worried about WTC7, but he failed to see the initial collapse of the Penthouse. He also calls the broken windows in the photo/video of WTC7 falling due to pixel problems, squibs. Add Jones to the list of WTC falling building time dolts.

 

[deep]

(Notice especially the uneven cut at the back of the column and the clinging previously-molten metal on both the outside AND the inside of the column, left photo, suggesting this was NOT cut using an oxy-acetylene torch, but rather that a highly exothermic chemical reaction was involved in cutting through this steel column.) JONES PAPER TODAY

Darn, Jones is implying thermite did it! Are you saying thermite was not used in the WTC and Jones is making up lies? He keeps changing his story!

He doesn't claim to have "proof" of thermite or thermate in any of the text you quoted, or in any of his papers that I've seen.

As I said before, there's a big difference between claiming to have proof of something and saying that something is consistent with something else. I'm not nit-picking here - Jones is very careful about what he says and how he words things, and while he's not immune to making mistakes, he also gets it right far more often than he gets it wrong.

With regard to the picture you posted - he very clearly states why he believes it suggests a highly exothermic chemical reaction: the previously molten metal can be seen on both the inside AND outside of the column, and the back-most cut is considerably uneven (especially when compared to the columns that were clearly cut with a torch).

Aside from that - looking at the picture, where is the guy with a torch? How was he able to position himself to make that cut? Where's the piece that he cut off? Aside from the evidence that torches were used elsewhere during the cleanup, there's absolutely nothing to suggest a torch was used here.

Now if Jones had said, "here I offer you definitive proof that an exothermic chemical reaction took place", I would agree that he's stretching it a little bit. Regardless, that's not what he said. He did say that this suggests an exothermic chemical reaction for X, Y and Z reasons.

Do you have anything other than "torches were used elsewhere during the cleanup"? If not, I can't rule out Jones' explanation as a possibility, and neither should you.

 

[Horace Wheeljack]

[/quote] Do you have anything other than "torches were used elsewhere during the cleanup"? If not, I can't rule out Jones' explanation as a possibility, and neither should you.[/quote]

Everything is a possibility! It's a possibility that David Hasselhof is responsible for rigging the towers. You need to look for evidence, not an endless list of possibilities.

 

[beachnut]

defend Jones with facts or stop quibbling

He doesn't claim to have "proof" of thermite or thermate in any of the text you quoted, or in any of his papers that I've seen.

As I said before, there's a big difference between claiming to have proof of something and saying that something is consistent with something else. I'm not nit-picking here - Jones is very careful about what he says and how he words things, and while he's not immune to making mistakes, he also gets it right far more often than he gets it wrong.

With regard to the picture you posted - he very clearly states why he believes it suggests a highly exothermic chemical reaction: the previously molten metal can be seen on both the inside AND outside of the column, and the back-most cut is considerably uneven (especially when compared to the columns that were clearly cut with a torch).

Aside from that - looking at the picture, where is the guy with a torch? How was he able to position himself to make that cut? Where's the piece that he cut off? Aside from the evidence that torches were used elsewhere during the cleanup, there's absolutely nothing to suggest a torch was used here.

Now if Jones had said, "here I offer you definitive proof that an exothermic chemical reaction took place", I would agree that he's stretching it a little bit. Regardless, that's not what he said. He did say that this suggests an exothermic chemical reaction for X, Y and Z reasons.

Do you have anything other than "torches were used elsewhere during the cleanup"? If not, I can't rule out Jones' explanation as a possibility, and neither should you.

Jones has used this as a smoking gun, you missed his work! Sorry, you should pay attention. See, Jones has to imply things so he can not be caught making outright lies, this is why he adds the stupid line "but rather that a highly exothermic chemical reaction was involved in cutting through this steel column"

but rather that a highly exothermic chemical reaction was involved in cutting through this steel column

Are you saying you fell for his lie, and you are falling for his suggestion? Classic truther non-logic (not a Vulcan).

Sorry, Jones' newest smoking gun for proof of thermite/thermate bringing down the WTC is his chip of thermite. Missed that too. Yes the cuts of the photos are clean up cuts. Prove they are not! You can not, why? Why are you so fact less?

Like I said, if you can not find errors in Jones' papers, you are lost and doomed to be a person with no real knowledge on 9/11. I guess it is doomed.

Cuts made after 9/11!

Now go find proof they are not. But you know I will post a photo of some guys cutting in a minute just for you, since your shallow research skills are showing as you now are a solid Jones believer in thermite, the idea he made up 4 years after 9/11. You guys are facts less, and funny. Disrespectful if you think about what you imply without facts.

Making cuts, clean up, proof; much more proof than Jones for thermite. Was he asleep for 4 years? What took him so long to come up with the thermite fantasy?

Jones makes up stuff about 9/11, here he says "Workers evidently peering into the hot “core” under the WTC rubble."

Workers evidently peering into the hot “core” under the WTC rubble.

Jones makes up more lies! Suggesting a lie? He puts this junk in his paper full of junk! Junk Journal, Junk Jones!

Jones, a pathetic old man who makes up lies and you defend him with zero facts. Nice try, but this was a light, they are using a light, they are recovering a body! Pathetic truth movement of lies. Have a great weekend.

The on topic issue must be the time for the buildings to fall, and Jones has to have thermite and RDX to make his false ideas on 9/11 happen. The truth of fire and failure do not fit his pathetic politically biased mind of woo on 9/11 issues. Pathetic

 

[stateofgrace]

None of your posts yet have convinced me that you are at all interested in a legitimate discussion. Please prove me wrong. Nonethelss, I hope my answer to The Red Worm here and Eeyore1954 here will answer most of your questions. If you have others, I will try to answer them.

Clarification: I have spent somewhere in the neighborhood of 400 hrs on the mass analysis which is a precursor to any collapse analysis.

None of my posts are structured to convince you of anything because I am not the one with concerns over the Sept 11th attacks you are. Maybe you forgot my earlier post but please allow me to remind you. I do not have to convince you of anything, nor do I have to disprove you. You have prove to me that you warrant merit and you also have prove you are right.

It is abundantly clear that you do subscribe to alternate theories despite your earlier denials. Equally so it is abundantly clear your idea of a structured debate in one based on your own terms. This being dismissing anybody who questions you as hecklers, Jreffers with typical preconceived notions.

If you wish to class me as typical Jreffer, I am actually honoured to be so because unlike you I have not signed a petition, unlike you I have not chosen to point the finger of accusation at innocent people and unlike you I have chosen not to excuse the murderous terrorists who committed this wicked act without absolute proof. The only one around here with any preconceptions , it would appear is you. You have gone out of your way to prove your already predetermined conclusion.

So as a typical Jreffer to a typical truther why don't you answer my questions and tell me why I should not dismiss you as yet another truther? Show me why your calculated times have any validity in backing up your theories. Show me why I should be in anyway impressed by your claims? Show me why your 400 hours have not been wasted.

Can you do that, truther?

Or maybe you could answer the question you threw at me earlier "What is the point of you being here? "

Or shall we call it a day on this pissing contest?

 

[GregoryUrich]

None of my posts are structured to convince you of anything because I am not the one with concerns over the Sept 11th attacks you are. Maybe you forgot my earlier post but please allow me to remind you. I do not have to convince you of anything, nor do I have to disprove you. You have prove to me that you warrant merit and you also have prove you are right.

It is abundantly clear that you do subscribe to alternate theories despite your earlier denials. Equally so it is abundantly clear your idea of a structured debate in one based on your own terms. This being dismissing anybody who questions you as hecklers, Jreffers with typical preconceived notions.

If you wish to class me as typical Jreffer, I am actually honoured to be so because unlike you I have not signed a petition, unlike you I have not chosen to point the finger of accusation at innocent people and unlike you I have chosen not to excuse the murderous terrorists who committed this wicked act without absolute proof. The only one around here with any preconceptions , it would appear is you. You have gone out of your way to prove your already predetermined conclusion.

So as a typical Jreffer to a typical truther why don't you answer my questions and tell me why I should not dismiss you as yet another truther? Show me why your calculated times have any validity in backing up your theories. Show me why I should be in anyway impressed by your claims? Show me why your 400 hours have not been wasted.

Can you do that, truther?

Or shall we call it a day on this pissing contest?

If you understand the calculations I have already posted, then there is not much to explain. If there is some part you don't understand, I can explain (at least as far as I understand). If you don't understand the calculations at all, then what could I possibly say to satisfy you? If you are unimpressed with my work and feel it's useless or even destructive, fine. I accept that. There are many who think my work is useful, interesting and constructive.

 

[stateofgrace]

If you understand the calculations I have already posted, then there is not much to explain. If there is some part you don't understand, I can explain (at least as far as I understand). If you don't understand the calculations at all, then what could I possibly say to satisfy you? If you are unimpressed with my work and feel it's useless or even destructive, fine. I accept that. There are many who think my work is useful, interesting and constructive.

Ah the "don't you understand my calculations ? " nugget.

Ok let go along with this and suddenly pretend I am not a qualified engineer, I have not got a BSC in Mechanical and electrical engineering ,I am not an offshore engineer and did not spent nine years in the Royal Navy as an electrical engineer. Lets suddenly pretend I am totally incapable of understanding your calculations. If I was to pretend that would it change your perception of me or would you still class me as a typical Jreffer heckler?

Ok lets go down your road now of pretending I find you work useful, interesting and constructive.

So Ok what exactly are you proving with your work? Who are you trying to convince ? Where does it lead? Does it back up your predetermined conclusion or does it cast doubt on it ?

You calculated the fall time was 21 seconds, but this is not relevant to anything unless you tell me what it is relevent to. Tell me why you spent hours and hours of study, outside your own field and why your study is relevant to anything.Tell me why I should look at your work.

Can you see this, bud, do you see why I do not wish to drawn into studying your calculations? No ? Because you refuse to tell me or anybody what relevance they have to anything. You refuse to accept what your posts clearly indict. That being you have an agenda, you have a preconceived notion and you have already determined your concussion. Without even looking at your work this is blatantly obvious. So why do you not just come out with it and state for the record you believe that the towers were brought down by something other than the planes and fires and state that your calculations are geared towards proving this?

Why do you keep denying this ?

 

[GregoryUrich]

Ah the "don't you understand my calculations ? " nugget.

Ok let go along with this and suddenly pretend I am not a qualified engineer, I have not got a BSC in Mechanical and electrical engineering ,I am not an offshore engineer and did not spent nine years in the Royal Navy as an electrical engineer. Lets suddenly pretend I am totally incapable of understanding your calculations. If I was to pretend that would it change your perception of me or would you still class me as a typical Jreffer heckler?

Ok lets go down your road now of pretending I find you work useful, interesting and constructive.

So Ok what exactly are you proving with your work? Who are you trying to convince ? Where does it lead? Does it back up your predetermined conclusion or does it cast doubt on it ?

You calculated the fall time was 21 seconds, but this is not relevant to anything unless you tell me what it is relevent to. Tell me why you spent hours and hours of study, outside your own field and why your study is relevant to anything.Tell me why I should look at your work.

Can you see this, bud, do you see why I do not wish to drawn into studying your calculations? No ? Because you refuse to tell me or anybody what relevance they have to anything. You refuse to accept what your posts clearly indict. That being you have an agenda, you have a preconceived notion and you have already determined your concussion. Without even looking at your work this is blatantly obvious. So why do you not just come out with it and state for the record you believe that the towers were brought down by something other than the planes and fires and state that your calculations are geared towards proving this?

Why do you keep denying this ?

We are simply back to your fantasy about me--your fantasy about me having some predetermined conclusion and some agenda.

I think my work may be relevant to validating or invalidating any of the current hypotheses. If you don't want to consider my work, fine.

 

[Myriad]

Hi Gregory,

Please do start a new thread to discuss strain energy, as you suggested you might do above. I don't want to derail this thread, but I'm curious as to why you subtract the elastic strain energy during the collapse (according to your points 6 and 7 above), but don't add it back in again as the structure breaks apart and that elastic strain energy is released. Also, I wonder about the effects of the now-belabored observation that inelastic bending of most columns was minimal on the best estimates of inelastic strain energy.

Respectfully,
Myriad

 

[GregoryUrich]

Hi Gregory,

Please do start a new thread to discuss strain energy, as you suggested you might do above. I don't want to derail this thread, but I'm curious as to why you subtract the elastic strain energy during the collapse (according to your points 6 and 7 above), but don't add it back in again as the structure breaks apart and that elastic strain energy is released. Also, I wonder about the effects of the now-belabored observation that inelastic bending of most columns was minimal on the best estimates of inelastic strain energy.

Respectfully,
Myriad

I will start a new thread for strain energies in general. Eventually, I will try to apply all of these issues to my Recalculation of Bazant and Zhou's Overload ratio.

As far as falltimes go, my thinking regarding adding the elastic strain energies back is as follows:

Newtons Bit and others have been modeling the structure as a mass with spring. If you imagine the spring breaking, both sections of the spring will unload. Early in the collapse, my hunch is that the springs will have time to unload before the next impact. Whether the sudden unloading or the associated vibration has a significant damaging effect on the structure is an interesting question. We could probably work out a simple formula based on the fall time between impacts. Actually getting into the occilation with damping and matching the phase to impact time seems like overkill, but I'm open for suggestions. A tough question is how realistic we can get without advanced computer simulations. Just the floor by floor simplification is probably giving the largest error anyway.

 

[eeyore1954]

There is no credible evidence pointing to CD,
Preparing the building for CD without detection would be a daunting task
How would the explosives/thermite /whatever survived the fire for the hour before the collapse
There is not a realistic argument for why it would have been brought down by CD
It is easy to tell one of the buildings was on the verge of collapse immediatly before collapse.
Doesn't watching a video of the collapse appear to indicate the building was plowing through the lower part with no need for any additional forces other than what initially caused the collapse , the mass of the building and gravity

If your calculated time disagrees with the reality of how long the collapse actually took by about 33%. you should take the time to consider why. Do you see how a CD could account for this difference if not you should consider another possible source of the difference. An error in your assumptions or calculations.

 

[Newtons Bit]

I will start a new thread for strain energies in general. Eventually, I will try to apply all of these issues to my Recalculation of Bazant and Zhou's Overload ratio.

As far as falltimes go, my thinking regarding adding the elastic strain energies back is as follows:

Newtons Bit and others have been modeling the structure as a mass with spring. If you imagine the spring breaking, both sections of the spring will unload. Early in the collapse, my hunch is that the springs will have time to unload before the next impact. Whether the sudden unloading or the associated vibration has a significant damaging effect on the structure is an interesting question. We could probably work out a simple formula based on the fall time between impacts. Actually getting into the occilation with damping and matching the phase to impact time seems like overkill, but I'm open for suggestions. A tough question is how realistic we can get without advanced computer simulations. Just the floor by floor simplification is probably giving the largest error anyway.

The structure is not critically damped, it's only 10% (maximum). This means that each impact imparts a vibration that is large and significant. This vibration can be measured as an elastic wave that propagates back and forth throughout the whole structure. Each "rebound" is about 10% smaller than the one proceeding it. The solution to this problem is relatively simple, though long:

mu'' + cu' +ku = p(t)

m = mass
c = damping thingamabober (it's late, I don't remember the exact term, but it is complicated).
k = stiffness matrix
p = force at time t
u = displacement at time t

c and k are 97 x 97 matrices, p is an array with 97 rows. I'm working on this problem now, just haven't had time to put it together.

 

[westprog]

When evaluating the collapse of the twin towers, I think that you really must consider a minimum of two separate times:

• the total duration of the collapse (which can vary greatly depending on the criteria used to determine the point at which a building has completely collapsed).

• the speed of the visible collapse front relative to free-fall speed.

The latter timing would be the most scientifically-significant measurement, in my opinion, because it's a more specific measurement and there's little room for interpretation.

For example, pretend you're trying to figure out how fast a certain car was going. If you're told that the car traveled 100 miles in 100 minutes, do you have all the information you need to determine if the car exceeded the speed limit? No, because it could have reached the 99th mile at the 30 minute mark, and then traveled roughly 2 mph the rest of the way.

The same holds true for the collapse of the twin towers - you're missing some critical information by only considering the complete collapse time (in addition to the problem of defining when a collapse is "complete").

In a number of the views of the collapse, it's possible to see the collapse starting, and the progression of the collapse front, before the whole thing disappears in a cloud of dust. Figuring out the total duration of collapse from ill-defined initiation to ill-defined completion is not really possible.

However, to see how long the pretty much intact top portion of the building takes to move a calculable distance should be relatively easy, and from that a value for the acceleration should be easy enough to produce. We can get the distance by counting windows.

 

[proxywar]

University of Buffalo Alumni Center (SUNY) and type in "Urich" in the search you will see that I graduated in 1990. Unfortunately, the type of degree (B.S.E.E.) is not given. Not that it matters but I also got a BA in music 1987 from the same school.

I went here https://www.ubconnect.org/olc/pub/BUF/register/register.cgi?FNC=Detail__Aresults_html___BUF___508423 is that you?

You mind filling in your Social Security Number then reposting?
Why is no bachelor of science in electrical engineering degree
given? Don't be so defensive I just want to trust you. And Correct, holding a BA in music is irrelevant.

 

[LordoftheLeftHand]

I am still amazed this free fall thing gets any traction. There is a well known video (it is a hand held video on the street near the towers, part of which has film of an injured pedestrian, I'll dig it up somehow) in which the first tower can be seen collapasing before the camera man takes off running. Right before he takes off, you can see actual "freefall" of part of the tower: namely a huge chunk of the facade that peeled off and fell down the side of the tower hitting the ground. Next you see some other free fall objects that were ejected, and then he runs. Point being: Debris is seen falling faster than the collapse front is moving; therefore the building cannot be collapsing at free-fall speed.

Don't be too disheartened. Remember when they first started making these claims they claimed the building was falling at FASTER than free fall speed. Then after sufficient ridicule they revised it to saying it fell at free fall speed. Now they seem to think it fell slower than free fall but not slow enough. They are slowly coming around to reality (kicking and screaming the whole way, of course).

LLH

 

[GregoryUrich]

I went here https://www.ubconnect.org/olc/pub/BUF/register/register.cgi?FNC=Detail__Aresults_html___BUF___508423 is that you?

You mind filling in your Social Security Number then reposting?
Why is no bachelor of science in electrical engineering degree
given? Don't be so defensive I just want to trust you. And Correct, holding a BA in music is irrelevant.

I trust you a little more than you trust me, but sorry no. If you have my SSN you can set up an account. I don't know why they don't give the degree. It's easier to tell if I know anything by reading my papers. I have never used my degree professionally, as I started in software at CSC immediately after graduating. I do have a patent in digital rights management (DRM). If you care to read that, you'll see I'm no bonehead.