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

[Loss Leader]

OK, so I exaggerated. Skeptics are not immune from throwing out an occasional fallcy. But since I can't find but 2 structural/civil engineers(David Zuniga and James Pegelow?) who dispute the official findings - I can only think that there arent many.

Just to head off any tr00fer who might see your post, you forgot Jowenko. Of course, Jowenko does NOT challenge the way the towers came down but only WTC7. And even then, he gave a couple of statements and then clammed up. He refuses to discuss the matter with anyone now.

 

[Foolmewunz]

deleted post - much funnier in concept than execution

 

[Roger_Harris]

Interesting that none of you choose to discuss John Skilling... Skilling recounts his people having carried out an analysis which found the twin towers could withstand the impact of a Boeing 707. He says, “Our analysis indicated the biggest problem would be the fact that all the fuel [from the airplane) would dump into the building. There would be a horrendous fire. A lot of people would be killed.” But, he says, “The building structure would still be there.”

Note that you're confounding two different things: the original design, and an analysis Skilling claims was done after the design was completed. There could be any number of different analyses with different parameters, so Skilling does not really contradict what Robertson said about what was "contemplated" in the design. In any case, there isn't any "plane crash" engineering formula where you can just plug in "180mph" or "600mph" and get an answer. In any analysis, what would be done would be to estimate the damage to the structure, then run some calculations to see if the remaining structure would carry the redistributed loads. And, it's virtually impossible to do that with any great precision, since it's virtually impossible to take into account all the variables. We can't do that even today with gigantic computer simulations, so any analysis done in the 60s would certainly be an "educated guess." At any rate, the structure did survive the initial crash, but nobody knows what the full structural damage was inside the building. The whole "designed to withstand the impact" thing is a red herring.

As for the fire, Skilling said the analysis considered that, somehow, but there are no details about what that means. And again, there is no "jet fuel fire" engineering formula; any analysis would be a set of assumptions, and very little empirical data is available even today about what those assumptions should be. But the proof that there wasn't anything special about the design with regards to a fire after a plane crash is that the fireproofing was just "to code," which is now considered inadequate even for a normal office fire. Skilling can easily say that the analysis indicated the building should stand, but that's just saying that they concluded that standard fireproofing was adequate. It doesn't really mean anything at all.

 

[apathoid]

Just to head off any tr00fer who might see your post, you forgot Jowenko. Of course, Jowenko does NOT challenge the way the towers came down but only WTC7. And even then, he gave a couple of statements and then clammed up. He refuses to discuss the matter with anyone now.

Yes, Jowenkos views don't exactly help either side all that much. To me, he is a stark reminder that woo is everywhere, even in highly technical disciplines(though its scarce there). But, to clarify, I didnt list him because he isnt a civil/structural engineer(AFAIK)

 

[defaultdotxbe]

OK, so I exaggerated. Skeptics are not immune from throwing out an occasional fallcy. But since I can't find but 2 structural/civil engineers(David Zuniga and James Pegelow?) who dispute the official findings - I can only think that there arent many. It could very well be that 99.9 % of the worlds civil engineering community agrees with the official story.

i would say 99.9% is a conservative estimate, i cant find any numbers for ASCE total membership, but it has over 20,000 life members, if .1% were truthers that 20 people right there, and we only see but 2 or 3

 

[apathoid]

i would say 99.9% is a conservative estimate, i cant find any numbers for ASCE total membership, but it has over 20,000 life members, if .1% were truthers that 20 people right there, and we only see but 2 or 3

Another sign of strong health was growth in membership, which increased to more than 139,000. These successes were due to a number of factors, including our focus on delivering what our members want by emphasizing on each program’s “member value” to ensure that we meet our members’ needs. As we grew, we focused even more on preparing the next generation of civil engineers for future challenges.

http://content.asce.org/annualreport/2005/execmessage.html

If there are 139,000 in the US, I would say that there are 500,000+ in the world. So that would make 0.1% = 500 CEs. So, as of now we 99.999996% of the civil engineering community on our team.
Perhaps I wasn't exagerrating, after all.

 

[jujigatami]

Back to the OP.

Don't we agree that the Titanic was designed to be UNSINKABLE?

 

[firecoins]

Back to the OP.

Don't we agree that the Titanic was designed to be UNSINKABLE?

The Titanic sank?!? I hope no one got hurt!

 

[DavidJames]

The Titanic sank?!? I hope no one got hurt!

Yes, sadly, it took the life of one of America's bright young actors, Leonardo DiCaprio

 

[defaultdotxbe]

Back to the OP.

Don't we agree that the Titanic was designed to be UNSINKABLE?

in theory, theory and practice are the same, in practice, they are quite different

Yes, sadly, it took the life of one of America's bright young actors, Leonardo DiCaprio

sadly?

 

[apathoid]

Titanics sinking was a false-flag operation by the Bush administration and Larry Silverstein.

http://www.euronet.nl/users/keesree/conspir.htm

The 'Olympic' was quite badly damaged, it would cost an awful lot more to repair it than was first thought, and, it would delay the launching of the Titanic by months......... So, on the night of April 14th - 15th, 1912, the 'Olympic' crashed in to an iceberg, just under 24 hours too early. She sank, taking 1,523 souls with her. The White Star Line now had a problem. They could claim money on the Titanic sinking but, they would have to pay a lot of it out to the bereaved. But, none the less, the White Star Line did make money out of the disaster, and, the Titanic (sailing under the name of the 'Olympic') served the company for 24 years without incident.

This website is dedicated to the eternal legacy of the RMS Titanic and to all of those who needlessly died one cold night in April, 1912...

^^I forgot the most important part! Sound familiar?

 

[Non Believer]

First off the criticism of not using proper syntactical structure is well taken, and my apologies for not giving folks that effort. I would like to thanks those who admitted it was at least possible that they designed these towers to withstand a crash and the resulting fire. Indeed admitting that Skilling considered a crash (and felt the towers would withstand a crash) does not mean that he could have been wrong. It does not prove the case by any means, but what it does show is that there was reason to believe that the towers shouldn't have collapsed. Combined with the with the absolute collapse of our air defense, there is plenty of reason to question the official story. For many of us this does not mean that we have reached a conclusion about who was behind the events of that day, but rather there was reason to consider the events of that day anomalous and worthy of investigation. We can argue about the results of what those investigations have brought, but there is no debate in my opinion that there are solid reasons to question the official story.
Two of the most common criticisms of my position

1- The engineers did plan for a jetliner crash, but did not consider the fires afterward-
To me this is a weak argument on the face of it. Are we really to believe engineers would really consider only the initial damage from a crash, and not the fire considerations? When we discuss bomb damage we do not normally discuss initial structural damage as separate from the fire portion. Also Skilling is clearly quoted as considering the fire damage and its effect on structural integrity.

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.

3- That the 767 is much bigger and carries significantly more fuel than the 707
Here are Boeings stats
Maximum weight Maximum fuel capacity Cruising speed
707 336,000 pounds 23,000 gallons 607 MPH
767 395,000 pounds 23,980 gallons 530 MPH
Some have mentioned the 707 367-80 (or the dash 80) has a cruising speed of around 550 MPH. This was the original prototype flown in 1954. The statistics here are from the 707 320-B which was in production in 1959. The kinetic energy released by the impact of a Boeing 707 at cruise speed is
= 0.5 x 336,000 x (890)^2/32.174
= 4.136 billion ft lbs force (5,607,720 Kilojoules).

The kinetic energy released by the impact of a Boeing 767 at cruise speed is
= 0.5 x 395,000 x (777)^2/32.174
= 3.706 billion ft lbs force (5,024,650 Kilojoules).

So in fact all things being equal the 707 provides 10 percent more kinetic energy on impact than does the 767. Most estimates of the speeds of flight 11 and 175 at impact are between 450 and 550 MPH which would supply less kinetic energy than Skillings calculation. Also there is no evidence I have seen to imply that a 767 would be carrying significantly more fuel than a 707. MIT's analysis concluded the speeds of flight 11 and 175 to be 429 and 530 MPH respectively. Please show me scenario that has a greater impact than what Skilling calculated for. Those of you who seem to be calculation happy should easily prove this wrong. Right?
P.S I have some more on Robertson and some reponses to loss leader and apathoid later today.

 

[Pyrrho]

They were designed to withstand a jetliner crash, and they did withstand a jetliner crash, but they were not designed to indefinitely withstand the subsequent fires. This is not unreasonable or unexpected.

I seriously doubt that any reasonable person would expect that a jetliner could crash and explode into any given skyscraper and expect that skyscraper to remain standing indefinitely. It is my opinion that the designers and engineers and constructors who built the World Trade Center towers considered the possibility that terrorists would fly jets into the towers at full speed. Quite possibly, they imagined an accidental impact, which would mean that any crash the envisioned would have hypothetically occurred at a much lower speed than the real-life attacks.

Presumably, the drawings and documents and other information pertaining to the actual design and construction of the towers is still available somewhere. Maybe someone ought to look them up--without facts, all that remains is conjecture and guesswork, and that's all pretty much worth nothing.

 

[senorpogo]

Ah, glad to see this old canard still gets rolled out.

Next, how about you tell us that some of the 9/11 hijackers are still alive?

 

[senorpogo]

An important point by Loss Leader that needs to be repeated:

The designers worried about a lost pilot looking for a landing strip in the fog. He would have been going a lot slower than faster than the absolute fastest his plane could possibly go.

To suggest that engineers designed the building to withstand a full speed airplane-missle (yes, I said missile) is complete and utter bull. But I guess I should expect such misleading tricks from the CT crowd.

 

[uk_dave]

1- The engineers did plan for a jetliner crash, but did not consider the fires afterward-
To me this is a weak argument on the face of it. Are we really to believe engineers would really consider only the initial damage from a crash, and not the fire considerations? When we discuss bomb damage we do not normally discuss initial structural damage as separate from the fire portion. Also Skilling is clearly quoted as considering the fire damage and its effect on structural integrity.

Fire protection is only any good so long as it is intact.

The chaos of a passenger jet impact on a structure makes it near impossible to economically model the possible effects of massive structural damage on the remaining fire protection.

Without fireprotection steel is vulnerable to ordinary fires fueled by furniture etc. That is why we protect steel from fire.

The design against disproportionate collapse would have to take into account the most probable scenario with regard to structural damage i.e a plane of a certain size hitting the building at a certain speed at a certain height.

But this design cannot fully appreciate the possible damage to fire protection.

So a building which has been structurally damaged is now stressed close to the limits of it's structural stability and is now being further damaged by fire.

If the fireprotection remains intact then we can assume that the structure will remain stable for as long as that fireprotection continues to work. During this time we expect that firefighting measures will have controlled and then extinguished the fire.

However, if the fire protection is destroyed in an unpredictable way, then we don't know how long the building will remain stable before support columns which are now taking much greater loads are weakened by the fire.

Therefore failure of the structure is probable within the expected period of protection afforded by the fire protection materials.

This is what happened.

This is why few people who know anything about buildings are surprised.

 

[Gravy]

Nonbeliever, the NIST reports that there is no documentation that any calculations were done in the 1960s of the 600mph impact scenario. That doesn't mean such calculations were never done, only that there is no way to prove it or to show what criteria were used. The calculations that we know were done were to determine structural integrity in a slower speed crash, and did not include the effects of thefuel load. The most important thing was that a tower not immediately collapse with everyone inside when struck by an airliner.

Leslie Robertson:
One of my jobs was to look at all of the possible events that might take place in a highrise building. And of course, in New York there had been two instances of aircraft impacts, the most famous being on the Empire State Building. Now, we were looking at an aircraft that was not unlike the Mitchell that ran into the Empire State Building. We were looking at an aircraft that was lost in the fog, trying to land. It was a low-flying, slow-flying 707, which was the largest aircraft of its time.

And so we made calculations not anywhere near the level of sophistication that we could today. But inside of our ability, we made calculations of what happens when an aircraft goes in and it takes out a huge section of the outside wall of the building. And we concluded that it would stand. It would suffer but it would stand. And the outside wall would have a big hole in it, and the building would be in place. What we didn't look at is, what happens to all that fuel? And perhaps we could be faulted for that, for not doing so. But that, for whatever reason, we didn't look at that question of what would happen to the fuel.
–Interviewed in New York: A Documentary Film, by Ric Burns

However:

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).

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.

WTC Design, Construction and Maintenance of Safety Systems http://fire.nist.gov/bfrlpubs/fire05/PDF/f05119.pdf Page 70-71

Note that there is no mention of fuel/fire analysis being conducted in the reported 1964 paper.

Robertson:
"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

Robertson:
" 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


Robertson
" The two towers were the first structures outside of the military and nuclear
industries designed to resist the impact of a jet airliner, the Boeing 707. It
was assumed that the jetliner would be lost in the fog, seeking to land at JFK
or at Newark. To the best of our knowledge, little was known about the effects
of a fire from such an aircraft, and no designs were prepared for that
circumstance. Indeed, at that time, no fireproofing systems were available to
control the effects of such fires."
http://www.nae.edu/nae/bridgecom.nsf/weblinks/CGOZ-58NLCB?OpenDocument

180 mph: Speed at which a Boeing 707 could hit the towers but still not destroy them, under the official engineering plan
http://www.time.com/time/covers/1101020909/anumbers.html

 

[Anti-sophist]

Very first post in this thread:

Can you show me the calculations or the certifying board that certified them? How about show me the standard according to any of the professional societies for how such a calculation would even be done? Any codes or statutes or legal standard for such a calculation? A textbook? A whitepaper? Anything?

This is an issue you continue to ignore. You claim there were calculations done. I want to see them, and I want to see who verified them. I want to see the methodology and who approved it.

There is no tried and tested method for performing this calculation. The engineers were guessing. Your assumption that engineer are infallible is baseless. I know, because I am one.

 

[uk_dave]

I know, because I am one.

So you did it?

 

[Anti-sophist]

1- The engineers did plan for a jetliner crash, but did not consider the fires afterward-
To me this is a weak argument on the face of it. Are we really to believe engineers would really consider only the initial damage from a crash

Show me the calculation. I could care less what your opinion on what they did or did not do. Your opinion is irrelevant. Show me.

Unless you can show me the calculation, that means you are choosing to believe a single engineer's claim of calculation, and choosing to believe that single engineer could not possible make a mistake, over hundreds of other engineers who say he was wrong.

Why do you think Skilling is so much more competant than the hundreds of other experts that not only will you trust him over them, you'll trust him blindly, without ever seeing his calculation.