Do we agree the towers were designed to withstand jetliner crash?

I like the fact that Non Believer conveniently forgets the fact that the crash modeling, to the extent that there was any, was done in 1964. 1964. Even assuming that the designers actually considered that a fully-fueled passenger jet would cruise at its maximum possible speed straight into the World Trade Towers, their calculations took place in 1964. The ability to model any type of crash, to predict how it would affect the core, to calculate how much extra strain their would be on the outer supports of the exoskeleton, to even figure out what would happen to the fuel, and to arive at any answer with any confidence was only as great as the computational capacity of an engineering firm in 1964.

The most powerful computer in the world was Control Data Corp.'s CDC6600. It had one 60-bit CPU. It had 2 megabytes of memory and processed 10 million instructions per minute. It had a speed of about 1/2 a megaflop and cost $40 million in yr. 2000 dollars. In 2000, a $2,000 laptop had a speed of 500 megaflops, 1000 times faster. (source)

As I've been reminded, anytime a Woo appeals to recognized authority, you can bet your last nickel it will be at least 40 years out of date.
 
I like the fact that Non Believer conveniently forgets the fact that the crash modeling, to the extent that there was any, was done in 1964. 1964. Even assuming that the designers actually considered that a fully-fueled passenger jet would cruise at its maximum possible speed straight into the World Trade Towers, their calculations took place in 1964. The ability to model any type of crash, to predict how it would affect the core, to calculate how much extra strain their would be on the outer supports of the exoskeleton, to even figure out what would happen to the fuel, and to arive at any answer with any confidence was only as great as the computational capacity of an engineering firm in 1964.

The most powerful computer in the world was Control Data Corp.'s CDC6600. It had one 60-bit CPU. It had 2 megabytes of memory and processed 10 million instructions per minute. It had a speed of about 1/2 a megaflop and cost $40 million in yr. 2000 dollars. In 2000, a $2,000 laptop had a speed of 500 megaflops, 1000 times faster. (source)

As I've been reminded, anytime a Woo appeals to recognized authority, you can bet your last nickel it will be at least 40 years out of date.

And ust to add to that description (I did Titan rocket Loads analysis on one of those puppies):
you could do dynamic analysis on 230 degrees-of-freedom. That was it. that is a mere 38 nodes, or physical locations. There were some tricks to get around it, ut they were not very efficient.
NASTRAN was just getting a toe in the water in Industry--and was still mostly COSMIC.
"Back of the envelope" calculations were state-of-the-art.
 
....so I hope you won't be taking Swirsky out of context anymore on your future rants.

Another small point. Kevin Ryan and others like to down play Robertson's role in the towers design. But lets see what others say.
http://www.sciam.com/article.cfm?articleID=000B7FEB-A88C-1C75-9B81809EC588EF21&catID=4

Fowler, senior engineer at the structural engineering firm of McNamara and Salvia. Fowler was then a junior member of the WTC's engineering firm of record, Worthington, Skilling, Helle & Jackson, later renamed Skilling Helle Christiansen Robertson. "As the Trade Center was so much lighter in comparison to earlier designs, it was a watershed building in the history of skyscrapers," he added. Leslie E. Robertson, then the project manager, was the engineer most responsible for the superskyscraper's design, Fowler noted.
 
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I don't think this has been mentioned but the fire protection was not put on right. Pictures clearly show that work crews responsible for the application did a bad job.

In the 1970's many construction crews were run by people apart of a "non-existant" organization that was known to be less than honest. This organization ran the docks, construction, unions, "garbage" disposal and ran numbers but not because they were into mathematics. At the time were still pretty powerful but not so much now. :scared:
 
2- That either a 707 couldn't go 600 MPH, or shouldn't have been expected to
I don't know what to tell you other than Skilling is on record as saying this is the speed he calculated for, and it is indeed typical that engineers over engineer there buildings. However cruising speed for a 707 is 607 MPH (regardless of what others have said), so 600 would not be an unusual number to consider.

.

600 mph is a very unusual number! You have not researched this a bit! your research is superficial.

All aircraft in NYC at 1300 feet are by law required to be below 250 KIAS!

You missed this.

All aircraft that are landing use flaps, Maximum speed with flaps usually is 210 KIAS going down as they use more flaps.

This is what kind of plane would hit the WTC a plane lost in the clouds trying to land a plane below 180 KIAS or slower!

They used 180 mph and 263,000 pounds. How could you miss this.

Airspeeds are 250 KIAS below 10,000 feet. All have to use this.

Why would someone hit the WTC at 600 mph? 600 mph at 1300 feet is faster than the plane is allowed by God. God tells us parts at 1300 feet will start to shed, God gave us air, air is thick at 1300 feet and forced Boeing engineers to use 355 KCAS as the top speed at SL to 27,000 feet for some airplanes.

How did the terrorist break these rules? The terrorist pushed up the engines at the last minute target in sight and got to 600 mph. They broke man's law and the aerodynamic limits on the plane. But they planes do not blow up when you speed they just break a little here and there based on design and time!

Go back to the research you are 5 years too late on 9/11, and 30 years too late taling about flying!

250 below 10,000 feet makes your 600 number very, very dumb!!!

That is why the engineer in the know is Robertson, he is alive and he has spoken. I can give you the real stuff, I have given you Robertson! You missed it you can not read.

250 below 10,000 feet makes your 600 number very, very dumb!!!

250 below 10,000 feet makes your 600 number very, very dumb!!!
 
I think the evidence is clear that the majority of the engineers of the towers have gone on the record that the towers were designed to withstand crashes of fully fueled jetliners. Leslie Robertson's famous quote that the coincidence theorists point to says that he was not aware of any calculations that were done on the resultant fires from a crash. He does not say that he knew there were no such calculations. The late John Skilling is clearly on the record that the towers were built to withstand such an event, as is the late Frank Demartini who died in the towers on Sept 11. De Martini can be seen on video claiming that the towers could withstand multiple jetliners. For those of you not aware of the history. The empire state building was struck by a B-25 bomber that was lost in the fog in 1945. Because of this event the designers of the towers intentionally designed the towers to withstand such an impact.
Fully fueled jetliners of 1960's vintage, yep indeedy.:)
 
Knots Indicated Airspeed, Knots Calibrated Airspeed.
 
Combined with the with the absolute collapse of our air defense, there is plenty of reason to question the official story.

I don't think we should discuss it here, but there isn't anything unusual or suspicious about the NORAD response.

See this paper for more details:

http://screwloosechange.xbehome.com/fst/NORAD.pdf

There's also a thread about it here:

http://www.internationalskeptics.com/forums/showthread.php?t=61752

If you want to discuss NORAD further, I suggest you post in that thread and not this one.
 
I don't think we should discuss it here, but there isn't anything unusual or suspicious about the NORAD response.

You mean the fact that our cold-war era air defense system geared to detect Soviet bombers coming over the north pole completely failed to detect or respond to civilian aircraft entirely inside the US? Or the fact that the only comperable interception of a civilian jet prior to 9/11 had taken almost an hour and a half? Or the fact that in just under two hours the civilian aviation authorities landed over 3,000 planes in an unprecedented clearing of the US airspace?
 
No one has disputed the calculations that a 707 at cruising speed actually supplies more kinetic energy than a 767, so I am still waiting on that one. As for Beachnut, I don't know what to tell you. You keep insisting that I have come up with the 600 MPH figure. I am quoting John Skilling, so if you don't like it why don't you mention that you think he is an idiot instead of calling me one. I do not think Skilling felt he was restrained by speed limits when did calculations for a potential disaster. Also you and others continue to insist that flights 175 and 11 were going 600 MPH. Are you just going to ignore that MIT says 429 and 537 MPH?
As for Anti-sophist, I felt I addressed your question with this quote from my second post-"As for the fact that beyond the 1964 white paper there is no record of this work (according to the NIST investigation). In general when I quote a top expert in a field as having made a statement to research he has done, I am not accustomed to being asked to reproduce his results. If his results are missing it is noteworthy, but it does not give you licensee to dismiss his statements on the subject. We do not go discounting top experts with exemplary records just because someone lost their research. How does that work in favor of the official story? In my opinion it casts doubt the other way since so many of the pertinent documents and evidence involved in 9-11 are missing." I know I am not allowed to cast any suspicion on the fact that seemingly key documents about the trade center are missing, but what would you have me do. Is this supposed to imply that he didn't do any research? And while we are on the subject maybe some of you can assist me in understanding exactly what information is available to the public regarding the engineering and construction of the towers. I assume you all believe in making as much as possible available to the public right? There is a photocopy of the 1964 white paper at pilots for 9-11 truth. Also we had this from Gravy in case you missed it A three-page document from the Port Authority of New York and New Jersey (PANYNJ or Port Authority) Indicates that the impact of a Boeing 707 flying at 600 mph was analyzed during the design stage of the WTC towers in February/March 1964 (Letter with an attachment dated November 13, 2003 from John R. Dragonette(Retired Project Administrator, Physical Facilities Division, World Trade Department) to Saroj Bhol (Design and Engineering Department, PANYNJ).
NB - Note to Roger Harris here who claimed that Skilling performed tests after the design. Your position is contradicted by this information. Skilling was considering the airplane crash during the design phase.
No documents on the aircraft impact analysis are available to review the criteria and method used in the impact analysis of a Boeing 707 aircraft on the WTC tower and to verify the assertion in the three-page document that "...such collision would result in only local damage which could not cause collapse or substantial damage to the building and would not endanger the lives and safety of occupants not in the immediate area of impact." Without the original calculations of the aircraft impact analysis, any comment on the document would be a speculation. In March 1964, a calculation was made by the Port Authority to determine the period of vibration of the tower due to an aircraft impact at the 80th floor. Although no conclusion was stated on the calculation sheet, it clearly indicates that the Port Authority recognized during the design stage the possibility of an aircraft impact on the tower.
Has anyone asked NIST where they looked for the documents, or where they ought to be? There explanation to this point is inadequate, though I doubt this aspect of the story concerns you.
To those of you who claim Skillings efforts were to a varying degree ineffective or ill informed in trying to protect against a jetliner crash, we have several problems.
1- I assume most of you believe the towers came down from the jetliner crashes alone. Thus you are of the belief that Skilling was wrong, so it is easy to infer his calculations were faulty. I of course do not believe that to be the proven case, so we have a little break in our realities on this. It would seem to me in the interest of neutral observation for both sides to consider Skillings claims without conclusions on what happened on Sept 11. I am sure that will get some howls from some quarters, but from my perspective I am trying to meet to you all halfway.
2- It seems a little hypocritical to say that making calculations on what factors will make a building remain standing or collapse is so complex that no one can be sure of such multi factorial assessments, and at the same time claim that a hypothetical analysis on the WTC collapse done by NIST is absolute proof. You start with the premise that the planes and the fires brought down the towers and NIST has to just fill in the blanks.
3- The titanic thing is cute, but what is it that you really say with it. That all technology is fallible and not to be trusted ? If so that's fine, but lets not pick and choose the technologies we see as legitimate and put our trust in without evidence.
 
I've put some paragraph spaces in for you. Please do the same yourself in future.

No one has disputed the calculations that a 707 at cruising speed actually supplies more kinetic energy than a 767, so I am still waiting on that one.

As for Beachnut, I don't know what to tell you. You keep insisting that I have come up with the 600 MPH figure. I am quoting John Skilling, so if you don't like it why don't you mention that you think he is an idiot instead of calling me one.

I do not think Skilling felt he was restrained by speed limits when did calculations for a potential disaster. Also you and others continue to insist that flights 175 and 11 were going 600 MPH. Are you just going to ignore that MIT says 429 and 537 MPH?

As for Anti-sophist, I felt I addressed your question with this quote from my second post-"As for the fact that beyond the 1964 white paper there is no record of this work (according to the NIST investigation). In general when I quote a top expert in a field as having made a statement to research he has done, I am not accustomed to being asked to reproduce his results. If his results are missing it is noteworthy, but it does not give you licensee to dismiss his statements on the subject. We do not go discounting top experts with exemplary records just because someone lost their research.

How does that work in favor of the official story? In my opinion it casts doubt the other way since so many of the pertinent documents and evidence involved in 9-11 are missing."

I know I am not allowed to cast any suspicion on the fact that seemingly key documents about the trade center are missing, but what would you have me do. Is this supposed to imply that he didn't do any research?

And while we are on the subject maybe some of you can assist me in understanding exactly what information is available to the public regarding the engineering and construction of the towers. I assume you all believe in making as much as possible available to the public right?

There is a photocopy of the 1964 white paper at pilots for 9-11 truth.

Also we had this from Gravy in case you missed it A three-page document from the Port Authority of New York and New Jersey (PANYNJ or Port Authority) Indicates that the impact of a Boeing 707 flying at 600 mph was analyzed during the design stage of the WTC towers in February/March 1964 (Letter with an attachment dated November 13, 2003 from John R. Dragonette(Retired Project Administrator, Physical Facilities Division, World Trade Department) to Saroj Bhol (Design and Engineering Department, PANYNJ).

NB - Note to Roger Harris here who claimed that Skilling performed tests after the design. Your position is contradicted by this information. Skilling was considering the airplane crash during the design phase.

No documents on the aircraft impact analysis are available to review the criteria and method used in the impact analysis of a Boeing 707 aircraft on the WTC tower and to verify the assertion in the three-page document that "...such collision would result in only local damage which could not cause collapse or substantial damage to the building and would not endanger the lives and safety of occupants not in the immediate area of impact."

Without the original calculations of the aircraft impact analysis, any comment on the document would be a speculation. In March 1964, a calculation was made by the Port Authority to determine the period of vibration of the tower due to an aircraft impact at the 80th floor. Although no conclusion was stated on the calculation sheet, it clearly indicates that the Port Authority recognized during the design stage the possibility of an aircraft impact on the tower.

Has anyone asked NIST where they looked for the documents, or where they ought to be? There explanation to this point is inadequate, though I doubt this aspect of the story concerns you.

To those of you who claim Skillings efforts were to a varying degree ineffective or ill informed in trying to protect against a jetliner crash, we have several problems.

1- I assume most of you believe the towers came down from the jetliner crashes alone. Thus you are of the belief that Skilling was wrong, so it is easy to infer his calculations were faulty. I of course do not believe that to be the proven case, so we have a little break in our realities on this. It would seem to me in the interest of neutral observation for both sides to consider Skillings claims without conclusions on what happened on Sept 11. I am sure that will get some howls from some quarters, but from my perspective I am trying to meet to you all halfway.

2- It seems a little hypocritical to say that making calculations on what factors will make a building remain standing or collapse is so complex that no one can be sure of such multi factorial assessments, and at the same time claim that a hypothetical analysis on the WTC collapse done by NIST is absolute proof. You start with the premise that the planes and the fires brought down the towers and NIST has to just fill in the blanks.

3- The titanic thing is cute, but what is it that you really say with it. That all technology is fallible and not to be trusted ? If so that's fine, but lets not pick and choose the technologies we see as legitimate and put our trust in without evidence.
 
No one has disputed the calculations that a 707 at cruising speed actually supplies more kinetic energy than a 767, so I am still waiting on that one.

...

3- The titanic thing is cute, but what is it that you really say with it. That all technology is fallible and not to be trusted ? If so that's fine, but lets not pick and choose the technologies we see as legitimate and put our trust in without evidence.


Yadda yadda. Get on with it. And learn how to use line breaks.

It is perfectly evident that the buildings survived the impact of the aircraft. Anyone who has seen the video can see this. It was what happened AFTER the impact that caused the collapse, and the designers of the WTC did not design for this (they had no way of doing so). Please get on with your point.

-Gumboot
 
No one has disputed the calculations that a 707 at cruising speed actually supplies more kinetic energy than a 767, so I am still waiting on that one.

As for Beachnut, I don't know what to tell you. You keep insisting that I have come up with the 600 MPH figure. I am quoting John Skilling, so if you don't like it why don't you mention that you think he is an idiot instead of calling me one. I do not think Skilling felt he was restrained by speed limits when did calculations for a potential disaster. Also you and others continue to insist that flights 175 and 11 were going 600 MPH. Are you just going to ignore that MIT says 429 and 537 MPH?

.

You can calculate the speeds yourself if you try. I use 470 and 590, but you can as I said find other number and also calculate them by yourself! I checked my number with others and the video, I calculated the speed and it looks good and is supported by others.

You said 600 mph, you are using 600 mph, I do not care where you got it from; I said they used 180 mph and 263,000 pound aircraft impact in the design. The WTC would take that impact. It took an impact and stood for long enough for most to get out! (this is an answer to the THREAD)

It would be unusual for planes to do 600 mph at 1300 feet for many reasons:

It is illegal - speed below 10,000 feet is 250 KIAS
It is prohibited due to stuctual damage and failure- 355 KCAS below 27,000 for some, see 767/757 tech data

I can talk about speeding aircraft all day, and we can find more experts on speeding aircraft. But bad things happen over time to planes (airliners expect of the Concord) at 1300 feet doing 600 mph. Since the terrorist did not care about bad things happening over time to the airplanes they were speeding from 470 to 590 mph. They were going to fast for the airplane, the airplanes can quickly go too fast because the engines will push them well past the aircraft limits in speed!!!!!!!!!

You have failed to understand why it is unusual to grab the top speed you CT nut cases find and post it!

You grab numbers and throw them around like you know something!

You push this junk science and ask questions and I answered you with, Robertson said he designed the building to take an impact from a slow moving aircraft, he is the one, not your pick, you picked poorly. Robertson is alive and can tell you!

You could write Robertson, I am not going to post gain since you fail to read my post. You can look it up I told you what the man who designed WTC structurally, the one and only best expert said!!!!

I posted you missed it cause you do not care about truth you care only about some CT junk or something you will never define.

So we have impact that day 5 to 7 times or more greater than the impact designed for, and the 10,000 gallons of fuel which started the biggest building fire I have every seen, I have never seen a 10 to 20 acre building fire.

10,000 gallons of fuel, not the low fuel state lost in the fog slow aircrraft impact Robertson planned on, but a high speed impact with tons of fuel.

You can cherry pick what you want, you are not looking for truth. You are looking for something to support what ever you want.
 
As for the line breaks Ive been editing from a write mail box, and the line breaks are getting lost in the process. Gumboot please explain why designers of buildings cannot calculate for airplane fuel fires.
 
Beacnut- Ignore MIT, Ignore John Skilling, and then tell me I pick and choose. Your figure of 180 MPH is a figure others have mentioned as a seperate calculation than the one Skilling references. You do not discuss. You insist that I accept everything Robertson as gold, and refuse to even accept that Skilling had a significant role. The fact that Robertson is alive plays no role on what they calculated for back in 1964. Ya he is around to comment on it, but it dosen't change what they did back then. And it is what they did back then that is the point of this thread
 
Beacnut- Ignore MIT, Ignore John Skilling, and then tell me I pick and choose. Your figure of 180 MPH is a figure others have mentioned as a seperate calculation than the one Skilling references. You do not discuss. You insist that I accept everything Robertson as gold, and refuse to even accept that Skilling had a significant role. The fact that Robertson is alive plays no role on what they calculated for back in 1964. Ya he is around to comment on it, but it dosen't change what they did back then. And it is what they did back then that is the point of this thread

Why, in your mind, is so Skilling so much more competant that you are willing to believe him, blindly and without his calculations, over hundreds of other engineers using more advanced techniques, tools, and modern computers?

Do you really think Skilling is that impressive that you are willing to dismiss hundreds of other experts with superior resources, even without seeing or verifying his calculation?
 
Beacnut- Ignore MIT, Ignore John Skilling, and then tell me I pick and choose. Your figure of 180 MPH is a figure others have mentioned as a seperate calculation than the one Skilling references. You do not discuss. You insist that I accept everything Robertson as gold, and refuse to even accept that Skilling had a significant role. The fact that Robertson is alive plays no role on what they calculated for back in 1964. Ya he is around to comment on it, but it dosen't change what they did back then. And it is what they did back then that is the point of this thread

Leslie E. Robertson, , said:
"The twin towers of the World Trade Center were designed to resist safely the impacting by the largest aircraft of that time...the intercontinental version
of the Boeing 707. In no small measure because of the high level of
competence of the men and women of LERA, each of the towers resisted the
impact of an aircraft larger than the 707. Yes, fire brought down the towers,
but the structural integrity created by the engineers of LERA allowed perhaps thousands of persons to evacuate the buildings prior to the fire-induced collapse." http://www.engr.psu.edu/ae/WTC/LesRobertson.html


Leslie E. Robertson, , said: on being hit by a commercial jet -
" It appears that about 25,000 people safely exited the buildings, almost all
of them from below the impact floors; almost everyone above the impact floors perished, either from the impact and fire or from the subsequent collapse. The structures of the buildings were heroic in some ways but less so in others. The buildings survived the impact of the Boeing 767 aircraft, an impact very much greater than had been contemplated in our design (a slow-flying Boeing 707 lost in the fog and seeking a landing field). Therefore, the robustness of the towers was exemplary. At the same time, the fires raging in the inner reaches of the buildings undermined their strength. In time, the unimaginable happened . . . wounded by the impact of the aircraft and bleeding from the fires, both of the towers of the World Trade Center collapsed."

http://www.nae.edu/nae/bridgecom.nsf/weblinks/CGOZ-58NLCB?OpenDocument
 
Beacnut- Ignore MIT, Ignore John Skilling, and then tell me I pick and choose. Your figure of 180 MPH is a figure others have mentioned as a seperate calculation than the one Skilling references. You do not discuss. You insist that I accept everything Robertson as gold, and refuse to even accept that Skilling had a significant role. The fact that Robertson is alive plays no role on what they calculated for back in 1964. Ya he is around to comment on it, but it dosen't change what they did back then. And it is what they did back then that is the point of this thread

I checked MIT's numbers and I like them, I like the ones I used, and they are all in the ball park. What number do you want to use.

Show me where Skilling said 600, or 607, or what ever. But planes do not do 600 at 1300 feet, airliners do not.

Told you why too. Sorry, just info, sorry you are upset, but you know the towers even took a large one ton of TNT equal impact and stood until they fell.

(answer)

I would love to fly at 600 mph in a jet at 1300 feet but the airliners are not built for it. But the one time over-speed you saw on 9/11 is typical of planes going fast at low attitude, bad things happen.
 

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