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CD = Free Fall?

Oh, BTW, I have 2-3 posts on previous pages that have gone unanswered. I even went point by point in one of them, explaining some of your retarded questions.

Please feel free to address them at any time....
 
Hi All,

12) (In lieu of the redundancy of #10 & #12) Does the false claim made by the NIST---after their sole control of the investigation for nearly six years---that WTC 7 did not enter freefall exhibit incompetence or intentional deception?

Courtesy of Jim Hoffman, who cached the NIST FAQ page from August of 2008:

QUESTION: In videos, it appears that WTC 7 is descending in free fall, something that would not occur in the structural collapse that you describe. How can you ignore basic laws of physics?

NIST RESPONSE: WTC 7 did not enter free fall. According to NIST analysis of WTC 7 video, the building collapsed 18 stories in 5.3 seconds. If the building exhibited free fall, this process would have taken just 3.9 seconds. The actual collapse time exceeded the free fall time by 40 percent."

"If the building exhibited free fall, this process would have taken just 3.9 seconds." Is this not another false statement, proven by later NIST findings? In the NIST 3-stage explanation of the descent of the top 18 stories, they appear to state that the building exhibited freefall and that those 18 stories took longer to fall than 3.9 seconds. However, there FAQ statement appears to assert that free-fall and 5.3 seconds are mutually exclusive---which they are not.

So, what I'm trying to discern here is---was this gross incompetence, or willful obfuscation of the later acknowledged truth?

Cheers,

Kurt
Shoof-
It seems to me that you are identifying a statement which preceded the final report that could be seen as imprecise at worst as evidence of either "gross incompetence or willful obfuscation". You've taken quite a leap there in my view. Furthermore, to ascribe such significance to the NIST description of the observed rate of descent of the building's facade, you must first establish why this rate of descent tells us anything significant about the failure mechanism which led to the building's collapse- you have not done so.

NIST has said all along that the observed 5.3 second descent time seen in the video exceeded the expected 3.9 second "freefall" descent time by 40%, no inconsistency there. You should also bear in mind that this 5.3 second time does not start at the observed beginning of the building's failure, which was marked by the collapse of the east penthouse. Understanding why the east penthouse disappeared into the building 8-9 seconds prior to the downward movement of the parapet wall would go a lot further in explaining the building's failure sequence than fixating on the irrelevant detail of "18 stories of freefall".

I'd agree with others here that your questions would receive greater attention and respect if you could manage to cut out the unnecessary and inflammatory hyperbole. And despite your leading, borderline intelligence-insulting questions, Dave Rogers has given you a thorough answer here which, if you had any integrity, would lead you to send him $1000 immediately.
 
So my response would be that NIST's initial statement, that the building did not enter freefall, is in the strictest sense correct; and since the NIST report was written for qualified professionals, it was appropriate that it should be worded this accurately. NIST's subsequent "admission" that the building exhibited a period of near-freefall acceleration is a vague, loosely-worded and scientifically worthless observation, which I would regard as having been thrown out as a sop to truthers in a misguided attempt to get them to stop making worthless pronouncements about things they don't understand.

Dave

Let's not forget the most important point Dave (and those who keep bringing free fall up especially). Thanks to the penthouse collapse, we are only discussing the collapse of the OUTSIDE of the building. The INSIDE of the building was already going.
 
.....


First of all, I'd like to clarify a few things before we delve into the NIST report. The challenge I made to journalist Curtis Cartier was an attempt to create a dialogue with, and research by, a Seattle writer who has spoken authoritatively on the subject of WTC 7---without actually having done much research. I'd already gone to my local congressman's office to get answers as to why NIST was refusing to release all of their modeling data, as that seemed of paramount importance to current and future building safety. Regardless of exactly what occurred with WTC 7, it seems logical that all NIST investigation data should be released to the public, in order to facilitate a better understanding of how a steel framed high rise building can be destroyed.
The plan, sizes, strength, details of the structural system have been published by NIST and can be analyzed by anyone competent to do so. About 2 years ago Gage grifted $6-8K to buy the FEA, ANSYS software needed to analyze this, what happened? No study by Gage, trips to exotic lands. Ask him the results.

.....
1) If, as the NIST report stated, there were only enough burnable materials to sustain a fire for 20-30 minutes in any given area, how is it that fires burned long enough to initiate collapse? According to their computer model, global collapse didn't manifest until the raging fires had burned continuously for 4 hours.
The fires licking the steel did not cause the collapse, the heat did. Turn on your oven to a high temperature and turn it off. The heat remains high, as in WTC7.

2) Regarding the thermal expansion that allegedly initiated the girder unseating from Column 79, did the NIST report exhibit scientific integrity by excluding thermal conductivity from their simulation?
3) Regarding the thermal expansion that allegedly initiated the girder unseating from Column 79, did the NIST report exhibit scientific integrity by only applying heat to Column 79---and not the connecting floor system---in their computer simulation?
4) Doesn't the NIST report acknowledge that steel and concrete have virtually the same coefficient of thermal expansion?
Thank you LSSBB. Answer below
1% Carbon Steel has a thermal conductivity of 43 k - W/(m.K)

For the following concrete types it is much less (same units):

Concrete, lightweight 0.1 - 0.3
Concrete, medium 0.4 - 0.7
Concrete, dense 1.0 - 1.8
Concrete, stone 1.7

You can try this in your back yard. Put a piece of steel next to a piece of concrete in the sunlight and see which one warms up quicker.:wink:

ETA: Note that Thermal Conductivity and Coefficient of Expansion are different concepts. Where the coefficient of expansions may be similar between steel and concrete, that is only useful in the concept of the fire if the materials are getting the heat into them at the same rate, which they are not in this case due to the differences in Thermal Conductivity

The Nelson studs spalled the concrete and eliminated the composite stiffening action of the slab.

5) The NIST report stated that they tested no actual steel from WTC 7. Does this exhibit scientific integrity?
They knew the temperatures , expansion of the steel and construction details. By the time NIST arrived on the scene other engineers and the City of New York had discarded this steel not them. NIST and the City of NY didn't know at the time that truthies would ask them this question, otherwise they would have saved the steel.

6) The NIST stated that they did not test for explosives. Does this exhibit scientific integrity in an impartial investigation into the collapse of WTC 7?
NIST examined all available evidence, including plans and videos, and found no evidence for explosives, but plenty for a fire induced collapse.

7) Does the verifiable evidence that the NIST report presents show that the fires burned long and hot enough to meet the four hire fire requirement exhibited by their computer model?
Yes again, the temperatures did the damage , not the location of the fires.

8) Do we know which way the 58 perimeter columns allegedly buckled, or is that an unknown?
They buckled laterally after they lost the critical floor bracing.

9) What was the cause of the alleged buckling of the 58 perimeter columns? Were they significantly weakened by the fires?
No, the columns buckled laterally after they lost their critical floor bracing.

10) If floors disconnected from the interior columns due to thermal expansion, what caused the interior columns collapse? Were the interior columns significantly weakened by fires?
No, progressive collapse of the floors attached to the columns removed critical columns bracing.
Similar to this. Small force input, large disproportionate collapse of the remaining structure.

The Official Paranoid Myth story is a mistaken opinion by incompetent troubled persons. The world has moved on. Future high rise buildings will be safer due to lessons learned from the 9/11 collapses. Join the rationals.
 
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Freefall has a very specific meaning; it means that the only significant force acting on a body is gravity.
Dave
This is really a key point. When truthers use the term "free fall" they want you to believe that for some period of time the entire upper 30+ floors of the building were falling like a ball with only gravity acting and no forces acting up from below. From a physics standpoint if the SUM of forces acting = mg there is no implication that the only force acting is mg (as truthers would have you believe). And, in fact, if that were the case there would be a nice flat section on their greenline acceleration graph for the entire 2.25 seconds in question.
 
@ AW Smith: Is not TFK's 'The vast majority of the columns were still pretty straight. Not grossly deformed or ripped apart.' in reference to the column end attachments?

Sorry, just saw this.

We haven't met. I'm a mechanical engineer. As such, my comments are best read absolutely literally.

"The columns were pretty straight. Not grossly deformed or ripped apart".

If I had meant the connections, I would have said the connections.

Here is a wealth of photos of ground zero. You can examine the columns for yourself, and see how little gross deformation (i.e., "crushing") and ripping apart of columns occurred.

Source:
http://911research.wtc7.net/wtc/evidence/photos/groundzero.html (Twin Towers photos)

http://911research.wtc7.net/wtc/evidence/photos/wtc7.html (WTC7 page)

Get familiarized with construction of external columns & spandrels:
http://911research.wtc7.net/wtc/evidence/photos/docs/gz_hd1391p24.jpg
http://911research.wtc7.net/wtc/evidence/photos/docs/gz_hd1391p26.jpg
http://911research.wtc7.net/wtc/evidence/photos/docs/gz_hd1391p28.jpg
http://911research.wtc7.net/wtc/evidence/photos/docs/gz_hd1391p29.jpg


Best images (IMO) for this purpose:
http://911research.wtc7.net/wtc/evidence/photos/docs/ground_zero_aerialb.jpg
http://911research.wtc7.net/wtc/evidence/photos/docs/ground_zero_arial2_ort.jpg
http://911research.wtc7.net/wtc/evidence/photos/docs/us/us_wtc35.jpg
http://911research.wtc7.net/wtc/evidence/photos/docs/us/us_wtc36.jpg
http://911research.wtc7.net/wtc/evidence/photos/docs/us/us_wtc37.jpg
 
Mr. Benshoof,

My compliments on your making the effort to write. Hopefully you aren't too far around the bend to listen & learn as well.

Introductions are delicate things, and must be handled gently. I will try to be gentle in my response to your introduction.

But, before we get to your questions, a little homework needs checking.

Hello fellow skeptics…
Like many people, I accepted the US Government conspiracy theory regarding the events of 9/11 without question for about five years, at which time I was presented with a number of pieces of information that put the validity of the USG CT into question for myself.
Kurt

You'll forgive me if I say that your second sentence (above) makes it sound like you're not much of a skeptic at all.

As a true skeptic, I must admit that I have some serious doubts about the truth of that sentence. My doubts exist for very good reason, I might add.

You see, there have been dozens of truthers who have used that line, but subsequent discussions showed that none of them meant it. They thought that it gave them "skeptic cred".

Unfortunately, when dealing with a bunch of people that are real skeptics, saying things that are implausible just undercuts one's credibility rather than enhances it.

So, I would like to check your skepticism just a little bit now.

Let's prioritize. Let's discuss the very few (say 3 or 4) MOST significant pieces of information that led to your revelations?

You say, you "were presented information that put the validity of the USG CT into question."

1. First, what were those most damning (to the "OGT") pieces of information?

2. Drawing on your skeptical skills, how did you check the information that you were presented. What tools did you bring to that task to see if that information was reliable, valid, etc.

Please show me that you haven't merely substituted one bit of unskeptical credulity for your acknowledged earlier one.

3. Presented information by whom?

4. The qualifications of the people that presented you with that info? Back to its source, please.

5. What were the logical steps that you used that convinced you that information was accurate?

I recognize at least one of the names of people who have posted comments on the Seattle Weekly blog page, and hope that we can all have a civil and informative discourse that will result in greater clarity and understanding of the subject matter. However, if any of you feel a compulsion to cast aspersions, I'm an ardent proponent of free speech, and will take no offense.

Good. I'm an engineer. We speak our minds. Plainly.

Makes most people feel uncomfortable.

I promise that I won't start the "casting aspersions" part.

First of all, I'd like to clarify a few things before we delve into the NIST report. The challenge I made to journalist Curtis Cartier was an attempt to create a dialogue with, and research by, a Seattle writer who has spoken authoritatively on the subject of WTC 7---without actually having done much research.

What were this writer's credentials that allowed him/her to "speak authoritatively"?

What were his/her assertions that you feel demonstrated their lack of research background?

I'd already gone to my local congressman's office to get answers as to why NIST was refusing to release all of their modeling data, as that seemed of paramount importance to current and future building safety. Regardless of exactly what occurred with WTC 7, it seems logical that all NIST investigation data should be released to the public, in order to facilitate a better understanding of how a steel framed high rise building can be destroyed.

First, I can see that, to a conspiratorial mind, the mere "keeping information confidential" may give the impression that people keeping the info have something to hide. The people whose job it is to decide what pieces of information are dangerous to release to the public view things differently.

They tend to be cautious. Overly cautious at times. They get no points, and lose no sleep, over the pieces of information that go out on their watch and cause no harm. They get lots of beating about the head & shoulders, lost sleep and internal feelings of failure, if some piece that they allowed to go out turns out to be used by nefarious persons in the commission of nefarious deeds.

Some people have decided that this information is sensitive. This is not an engineering question. It's a "National security policy" question.

In learning epistemology, the first thing that you learn is to direct all of your questions at appropriate experts. This one is for a "national security policy" expert. Not an engineer.

I personally find the injunction against its release silly. Virtually all of the info that might be dangerous is already in the public domain.

But I also have the humility to acknowledge that it is not an issue within my realm of expertise. Others have to make those calls. Just as, in a company, marketeers & QC & sales & manufacturing, etc. may make different - AND VALID, from their perspective - calls than I would (as an R&D engineer). I don't presume that, because they make different calls than I would make that they are nefarious, or have something to hide.

Now, regarding your questions ...

In no particular order of importance, here are some preliminary questions:

1) If, as the NIST report stated, there were only enough burnable materials to sustain a fire for 20-30 minutes in any given area, how is it that fires burned long enough to initiate collapse? According to their computer model, global collapse didn't manifest until the raging fires had burned continuously for 4 hours.

2) … did the NIST report exhibit scientific integrity by …?

3) … did the NIST report exhibit scientific integrity ...?

4) Doesn't the NIST report acknowledge that steel and concrete have virtually the same coefficient of thermal expansion?

5) … Does this exhibit scientific integrity?

6) … Does this exhibit scientific integrity ...?

etc. etc. etc.

Let me ask you to look at this from the other side of the desk.

Suppose that you were a cardiologist, with several decades of experience in doing bypass heart surgery. Then some guy walks into your office and starts grilling you, politely, about a case that you'd done, using the terminology that you've used here.

But substituting "did you use best medical practices by …" And bringing up questions of the caliber, "did you use best medical practices by administering anesthesia prior to cracking his chest?"

Followed by "BTW, what is the reason that you use anesthesia in the first place?" [Note that this is the caliber, the sophistication, of some of your questions.]

Would you continue talking to that guy?

If you did, you'd be a fool. And not many fools make it to have a decade long career in cardiology.

I will happily answer (as best I can) any questions that you have that haven't already been answered by others.

I have two pieces of info to request before doing so.

Your age.
A brief statement of your background (especially vis a vis engineering).

In the interest of fairness:
I'm 58.
I've been a working mechanical engineer since the mid '70s to this day.

If you answer these simple questions, I'll be happy to try to answer any questions that you have that remain.

Regards,

Tom
 
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Yes you are...you have been asked by me and numerous other members to elaborate on what you think happened on 9/11...but you refuse to do so. To me that says "coward".

Prove us wrong. Give us a detailed account of what you think happened that day.

Dude - that's page one of the truther manual. NEVER give a detailed account.

The idiots who wrote and read the manual know full well that if they do that, their blatant lies are exposed to a point not even the most dishonest truther can recover from.
 
Neither.

Let's look at the actual acceleration data, shall we?

[qimg]http://www.internationalskeptics.com/forums/imagehosting/thum_147644ebb9aa77c398.jpg[/qimg]

What's clear from this is that there is no period of freefall. There is a portion of the graph for which the acceleration is close to 1G. There are two possibilities here; either the errors in the measurement are comparable with or greater than the fluctuations in the acceleration, in which case we cannot determine the maximum acceleration to a better precision than somewhere between 0.8G and 1.2G, or the errors in the measurement are less than the fluctuations in the acceleration, in which case we can only identify four points at which the varying acceleration is instantaneously equal to 1G. It's imprecise and incorrect to claim that a part of the collapse was in freefall, therefore. Freefall has a very specific meaning; it means that the only significant force acting on a body is gravity. Clearly, in the above graph, either there are other significant time-varying forces acting on the body under observation, or the measurement is not accurate enough to determine that a period of freefall occurred.

So my response would be that NIST's initial statement, that the building did not enter freefall, is in the strictest sense correct; and since the NIST report was written for qualified professionals, it was appropriate that it should be worded this accurately. NIST's subsequent "admission" that the building exhibited a period of near-freefall acceleration is a vague, loosely-worded and scientifically worthless observation, which I would regard as having been thrown out as a sop to truthers in a misguided attempt to get them to stop making worthless pronouncements about things they don't understand.

Dave

http://www.youtube.com/watch?v=eDvNS9iMjzA

WTC7: NIST Finally Admits Freefall (Part I)


DRYLABBING.
http://en.wikipedia.org/wiki/Fabrication_(science)


Final report.
2.2 seconds of free fall.
 
You asked, I gave you an answer, you rejected that answer out of hand, and in a rather gruffy tone.
Nonsense.

I asked A W Smith.

You replied with...
Collapse of core, as evidenced by the collapse of the mechanical penthouses before release of north wall roofline - 7 seconds, give or a take a bit.
...to which my response included...
A W Smith seems to be talking about "building 7 losing altitude before the claim of freefall", and you are talking about partial core failure start time.

East penthouse descent time could be said to be about 7s prior to release of the NW corner.

That you have responded "oblivious" is part of what I was saying earlier. I leave you folk for a while and the standards drop rapidly :) In case you didn't pick it up, exactly what part of your answer are you thinking I rejected, in any way ?

Of course, the only person able to clarify what A W Smith actually meant is A W Smith himself. I suggest he clarifies, rather than posting such, er, high-brow comments like "Are you having a problem reading English??? Go back and read it again or forever be known a dunce.". Quality. Or he could say nothing. As long as there's no-one out there thinking that "building 7 was losing altitude for 7s before "freefall"" then we're all good, whether that's what he intended, or not.
 
Broke his femur now he cant read.

Nonsense.

I asked A W Smith.

You replied with...

...to which my response included...


That you have responded "oblivious" is part of what I was saying earlier. I leave you folk for a while and the standards drop rapidly :) In case you didn't pick it up, exactly what part of your answer are you thinking I rejected, in any way ?

Of course, the only person able to clarify what A W Smith actually meant is A W Smith himself. I suggest he clarifies, rather than posting such, er, high-brow comments like "Are you having a problem reading English??? Go back and read it again or forever be known a dunce.". Quality. Or he could say nothing. As long as there's no-one out there thinking that "building 7 was losing altitude for 7s before "freefall"" then we're all good, whether that's what he intended, or not.


Did you even read the post where I clarified for you what I meant? Or will you continue to be a belligerent jackass trying to wedge words into my mouth? dont you have some graphs to attend to?
 
Can we all agree that it is pointless to try to teach calculus to a parrot who continually just squawks:

"Awwwwk.
Free fall. Free fall.
Cracker.
Free fall.
Awwwwk."

Polly Moore knows more words:

"Al Qaeda, central bank, Awwwwk, CIA, Awwwwk, Awwwwk, Libya, Qaddafi, Awwwwk, rebels, Awwwwk"
 
You've got all those video's of controlled demo that prove the blazingly retarded theory that 2.2 seconds of freefall means CD?

No?

No resistance means no resistance. Cascading debris encounter resistance entire floor by entire floor.

Absence of resistance means CD.
 

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