Would the WTC Twin Towers have collapsed from fire alone, without plane impact?

[econ41]

In a meandering off-topic discussion in another thread @Henkka asked me this question:

(Is it your position that the WTC towers could have collapsed from fire alone, without plane impact?)

Whilst I have many times touched on the topic I am not aware of any thread that debunks the specific issue. So I will present my outline argument that without the plane impacts both WTC Twin Towers would probably have survived any likely fire that could have occurred.

My contention is that the 9/11 Twin Towers collapses resulted from a combination of the consequences of aircraft impact and unfought fires. That much is the 'accepted narrative', or the 'extant hypothesis'. It has not been 'rebutted' or 'falsified'.

I aim to show for @Henkka that the combination of the two was needed. So please excuse the 'probably' and 'likely' disclaimers - they refer to a 'fire alone' situation which is moot to the argument I will present.

Stated briefly in five parts my argument is:
1) The fires which did cause the 9/11 Twin Towers collapses were far greater than the buildings were designed to withstand;
2) The scale of the fires was in excess of the design envelope in four factors which resulted from the aircraft impacts. Those four factors are:
(a) The fuel was concentrated as a consequence of "Boeing Dozing";
(b) The fires started simultaneously on several levels;
(c) Aircraft fuel acted as an accelerant in starting the fires; AND
(d) Sprinkler systems were compromised. (Tho' personally I doubt that factor was significant >> not relevant to this thread's discussion.)

All four of those were consequences of aircraft impact. Without aircraft impact the fires of the scale of 9/11 could not have been initiated. (Without a major deliberate logistic exercise >> out of scope of this discussion.)

And I submit that what I have outlined is prima-facie proof of the topic OP question. I am prepared to offer further detailed 'proof' if a discussion ensues.

Given my position which answers @Henkka's question I will now briefly comment on the supporting comments that @Henkka's posted in his disagreement with my comments:

Because of what you said here:

Before 9/11, not a single tall building had ever collapsed from fire, no matter how severe.

<< An irrelevant claim despite it being often repeated.

Yet not even 2 hours after the Twins were struck by planes, both had collapsed to the ground.

<< Correct - and the primary topic for discussion. AKA 'explaining why' the buildings collapsed.

The natural conclusion from that is that large planes going at high speeds striking buildings can cause collapse...

It is plausible if the size of the plane is sufficient to overwhelm the building. It did not happen at WTC on 9/11 so the comment is of no relevance. The plane impacts did not directly cause the collapses.

Not that fire alone can cause collapse, since that goes against 100% of our previous experience of fires in tall buildings.

<< A common false claim from "truthers". Both assertions are false. The first is outright untrue. The second is a 'false generalisation'. And the true status of debate is that the WTC collapses have been explained and the explanatory hypotheses have not been legitimately falsified.

It's completely logical to assume then that the plane impact played a huge role in causing the building the collapse,..

<< Yes. That is my position. The aircraft impacts were essential to the 9/11 collapses. Not as a direct result of structural damage but by causing the four factors I outlined previously. Probably assisted by the structural damage caused by the initial impact.

and not just by setting fires.

The structural damage from the impacts may have contributed. Most explanations assert that it was a contributing factor. BUT the Towers both withstood the initial structural damage. Therefore the fires were essential. And the scale of fires could not have been achieved by other means. (And 'proof' of that can wait another time or any discussion.)

So:

(Is it your position that the WTC towers could have collapsed from fire alone, without plane impact?)

No!

Sadly the question is somewhat ambiguous. For reasons well outside the scope of this OP topic. (Hint - the "rules" under which WTC was designed were arguably not sufficient to meet contemporary - 2022 - expectations. A somewhat complex topic already under discussion elsewhere.)

 

[Henkka]

All four of those were consequences of aircraft impact. Without aircraft impact the fires of the scale of 9/11 could not have been initiated. (Without a major deliberate logistic exercise >> out of scope of this discussion.)

This makes it sound like your answer is more of a "Yes, but" rather than a "No". Like yeah in practice, nobody could spray fuel all over several floors of the towers without being stopped by security. But I wasn't questioning the practicality of doing that, just theoretically if someone were to do that, would the building collapse? It sounds like you think yes, it would. So I don't understand why you said this is "out of scope".

It is plausible if the size of the plane is sufficient to overwhelm the building. It did not happen at WTC on 9/11 so the comment is of no relevance. The plane impacts did not directly cause the collapses.

Whether or not the plane impacts directly caused the collapses isn't relevant to what I was saying there... What matters is what people thought caused the collapse at the time, since my point was about how surprised Bazant ought to be that a third tower collapsed. I meant that in the hours between noon and 5PM on 9/11, it was logical to think "Plane impact can cause buildings to collapse", not "Fire alone can cause buildings to collapse".

Btw I'm surprised you didn't bring up fire proofing being stripped from the columns, do you not agree with NIST on that?

 

[econ41]

@Henkka My goal in OPing this thread is to have a discussion that remains on topic. Let's see if we can get you to address the topic of this thread without evasions or derails. Let's start with what I actually said and see if you EITHER:
1) Agree; OR
2) Disagree and can preset reasoned argument.
THEN I can address your attempts to conflate two very different scenarios. I said:

1) The fires which did cause the 9/11 Twin Towers collapses were far greater than the buildings were designed to withstand;

Do you agree or not? If "not" please present your reasons.

Then I said:

2) The scale of the fires was in excess of the design envelope in four factors which resulted from the aircraft impacts. Those four factors are:
(a) The fuel was concentrated as a consequence of "Boeing Dozing";
(b) The fires started simultaneously on several levels;
(c) Aircraft fuel acted as an accelerant in starting the fires; AND
(d) Sprinkler systems were compromised. (Tho' personally I doubt that factor was significant >> not relevant to this thread's discussion.)

Do you agree with those four? If "not" present your reasons.

Then I said:

All four of those were consequences of aircraft impact.

Again do you agree or not?

Without aircraft impact the fires of the scale of 9/11 could not have been initiated. (Without a major deliberate logistic exercise >> out of scope of this discussion.)

IF you want to present a counterclaim OR try one more of your goalpost shifts then outline why you think that a deliberate fire starting exercise is plausible at a scale big enough to achieve what the aircraft impact did achieve.. be my guest. OP your own thread. And please don't play this sort of silly game:

Like yeah in practice, nobody could spray fuel all over several floors of the towers without being stopped by security. But I wasn't questioning the practicality of doing that, just theoretically if someone were to do that, would the building collapse? It sounds like you think yes, it would.

Yes of course it is plausible. Not quite as plausible as the use of mini-nukes. More plausible than Judy Woods energy beams from space. BUT completely ridiculous,

 

[Henkka]

IF you want to present a counterclaim OR try one more of your goalpost shifts then outline why you think that a deliberate fire starting exercise is plausible at a scale big enough to achieve what the aircraft impact did achieve.. be my guest.

The question isn't whether or not something like that is plausibly doable... It's a hypothetical, to understand your position better.

So again, just hypothetically... If there was no physical damage to the tower from impact, and someone went up the stairs with a big hose connected to a tanker of fuel, doused floors 93-99 and lit it on fire, what do you think would happen? Let's also say the sprinklers are off and nobody arrives to fight the fire. Do you think this would happen:

 

[econ41]

So again, just hypothetically... If there was no physical damage to the tower from impact, and someone went up the stairs with a big hose connected to a tanker of fuel, doused floors 93-99 and lit it on fire, what do you think would happen?

Your evasion noted. As I have said - if YOU want to present a counterclaim. Whether or not you want to hide behind words like "hypothetical" then present YOUR scenario. Showing that you comprehend the logistic issues. ONE example - how do you get fuel up a hose from ground level to floors 93-99?

I OPed this thread with the clearly stated goal of identifying and constraining discussion on the OP topic. I will not be chasing your evasions and other debating trickery.

 

[Henkka]

ONE example - how do you get fuel up a hose from ground level to floors 93-99?

Sigh, it doesn't matter, it's a hypothetical... For the purpose of this discussion, it can be a magic hose for all I care. Or barrels of fuel are brought up with the elevators and then dumped on the floors. Point is, let's imagine floors 93-99 of the North Tower are doused in fuel for whatever reason, with no impact damage whatsoever, and then that fuel is set on fire. In such in imaginary, hypothetical scenario, what do you believe would happen?

 

[econ41]

1) The fires which did cause the 9/11 Twin Towers collapses were far greater than the buildings were designed to withstand; In such in imaginary, hypothetical scenario, what do you believe would happen?

You would still wriggle out by moving the goalposts. Let me know if you want a serious discussion.

Your "hypothetical" is not defined sufficiently for a sensible answer even if we ignore the logistic impracticalities. And I won't accept your invocation of "magic".

Of course, a fire could cause collapse provided it was big enough to overwhelm the resources available to resist it. Remember that is the foundation issue that truthers deny. That steel frames are vulnerable to fire.; It is only a question of the "size" (Intensity, available fuel, extent, rate of start-up and progression and the level of "opposition" (insulation. sprinklers and active fire fighting).

Until you deal with that issue your loaded questions are pointless. YOU are the one presenting your "hypothetical" without specifying the relative scale of fire compared with the "defences". Hit it with a large enough fire and any steel frame building will collapse. So stop playing games with your undefined "hypothetical".

As I said in my opening posts,

Without aircraft impact the fires of the scale of 9/11 could not have been initiated. (Without a major deliberate logistic exercise >> out of scope of this discussion.)

IF you want to define a deliberately caused fire that was bigger than the actual 9/11 fires - start your own thread and stop playing games here.

Let's get back to the topic. I asked you:

1) The fires which did cause the 9/11 Twin Towers collapses were far greater than the buildings were designed to withstand;

Do you agree or not? If "not" please present your reasons.

 

[Henkka]

Of course, a fire could cause collapse provided it was big enough to overwhelm the resources available to resist it.

Okay, so your answer to my hypothetical seems to be "Yes, the building would collapse". You just don't think there was any other plausible way of delivering the fuel to floors 93-99 other than a plane strike. But clearly if we just imagine the fuel was delivered to those floors through some other method and then set on fire, the same collapse should occur, according to you. But correct me if you think I'm misinterpreting you.

YOU are the one presenting your "hypothetical" without specifying the relative scale of fire compared with the "defences".

I obviously meant the fire would be of the same scale as the one that occurred on 9/11, otherwise the hypothetical would be totally pointless... To answer the original question, what would happen to the building if there was a similar fire, but no plane impact damage.

1) The fires which did cause the 9/11 Twin Towers collapses were far greater than the buildings were designed to withstand
Do you agree or not? If "not" please present your reasons.

No, I don't agree, because they were designed to withstand such fires:

"We looked at every possible thing we could think of that could happen to the buildings, even to the extent of an airplane hitting the side," said John Skilling, head structural engineer. "However, back in those days people didn't think about terrorists very much."
(...)
"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," he said. "The building structure would still be there."

Skilling - a recognized expert in tall buildings - doesn't think a single 200-pound car bomb would topple or do major structural damage to a Trade Center tower. The supporting columns are closely spaced and even if several were disabled, the others would carry the load.

"However," he added, "I'm not saying that properly applied explosives - shaped explosives - of that magnitude could not do a tremendous amount of damage."

https://archive.seattletimes.com/archive/?date=19930227&slug=1687698

 

[Mendel]

2) The scale of the fires was in excess of the design envelope in four factors which resulted from the aircraft impacts. Those four factors are:
(a) The fuel was concentrated as a consequence of "Boeing Dozing";
(b) The fires started simultaneously on several levels;
(c) Aircraft fuel acted as an accelerant in starting the fires; AND
(d) Sprinkler systems were compromised. (Tho' personally I doubt that factor was significant >> not relevant to this thread's discussion.)

If you guarantee these four factors, but otherwise changed nothing about the tower (structural steel and its fire-proofing remain intact), would it collapse?

 

[Jeffrey Orling]

From the event we know that the towers had sufficient reserve structural strength to "suffer" the loss of multiple columns. We also know that demise/collapse was a runaway floor collapse from the levels were the planes hit. This happens to the levels which received almost full plane loads of jet fuel. We know that too much heat is fatal to the integrity of steel frames. We know the sprinkler system was rendered useless by the plane strikes. We know there was not fire fighting.
My conclusion is that the fires overheated the steel to a point where progressive failures in the frame occurred until the frame at those levels was incapable to support the "block" above... which collapse and set off the runaway unstoppable from collapse. The plane caused mechanical damage was contributory, but not sufficient to collapse the towers
The 7WTC reinforces the notion that unfought long burning fires produce fatal outcomes for steel frames. However the design elements / choices / features played a role in how, how long failure took, and the form of the collapses.

 

[Jeffrey Orling]

If you guarantee these four factors, but otherwise changed nothing about the tower (structural steel and its fire-proofing remain intact), would it collapse?

I think - yes

 

[Gamolon]

No, I don't agree, because they were designed to withstand such fires:

No, they weren't.

Leslie Robertson's quote below. Bolding is mine.
https://www.nae.edu/Publications/Br...ecurity/ReflectionsontheWorldTradeCenter.aspx

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.

 

[FatPhil]

I think - yes

I suspect you wouldn't even need (b). However, this particular speculation about counterfactual situations is a diversion from the thread topic.

 

[Henkka]

No, they weren't.

Leslie Robertson's quote below. Bolding is mine.
https://www.nae.edu/Publications/Br...ecurity/ReflectionsontheWorldTradeCenter.aspx

They both say the impact of a jet airliner was considered. If they made no specific calculations what exactly would happen in the fires following the impact, it would seem to be because they thought it was self-evident the building would survive those fires. When you consider Skilling's wording, "The building structure would still be there", it seems to me he didn't even consider fire-induced collapse a remote possibility. And if you read the article further, he clarifies he believed that the only thing that could bring the towers down was controlled demolition by a "top expert" in that field. Now, I'm not trying to posthumously claim Skilling to be on my side. Nobody knows what he would have thought of the collapses if he had been alive in 2001. But if a lead engineer on the WTC project didn't consider it plausible that plane impact and fires could seriously damage the building, let alone completely destroy it, it seems absurd to say the fires were much worse than what the building was designed to withstand.

I thought this statement from Robertson was curious:

When the two towers were finished, the World Trade Center stood proud, strong, and tall. Indeed, with little effort, the towers shrugged off the efforts of terrorist bombers in 1993 to bring them down. The events of September 11, however, are not well understood by me . . . and perhaps cannot really be understood by anyone.

 

[Gamolon]

They both say the impact of a jet airliner was considered. If they made no specific calculations what exactly would happen in the fires following the impact, it would seem to be because they thought it was self-evident the building would survive those fires. When you consider Skilling's wording, "The building structure would still be there", it seems to me he didn't even consider fire-induced collapse a remote possibility.

It doesn't matter what you think they meant or what they "seem" to have been thinking. Robertson clearly states that they were NOT DESIGNED for fires caused by the plane impacts. He was one of the lead structural engineers for the twin towers.

 

[Henkka]

It doesn't matter what you think they meant or what they "seem" to have been thinking. Robertson clearly states that they were NOT DESIGNED for fires caused by the plane impacts. He was one of the lead structural engineers for the twin towers.

So if you asked Skilling or Robertson before 9/11 if they thought the WTC towers would survive a large, fuel-fed fire enveloping multiple floors, what do you think they would have said? Or, well, we already know what Skilling would answer, "The building structure would still be there". Do you think Robertson would have said it's possible the building could totally collapse, since "no designs were prepared" for such a circumstance?

 

[Gamolon]

So if you asked Skilling or Robertson before 9/11 if they thought the WTC towers would survive a large, fuel-fed fire enveloping multiple floors, what do you think they would have said? Or, well, we already know what Skilling would answer, "The building structure would still be there". Do you think Robertson would have said it's possible the building could totally collapse, since "no designs were prepared" for such a circumstance?

Who cares what Robertson might have said prior to 9/11?!

You made the claim that the towers were designed for the fires as a result of a plane impact. You supported that statement with an ambiguous quote from Skilling where you have to "interpret" what you "think" he "seemed" to have meant.

I supplied a quote from Robertson that clearly states that no designs were incorporated handle the resultant fires due to a plane impact.

I'm not playing these games with you. You made a claim and it was shown to be incorrect.

 

[Henkka]

Who cares what Robertson might have said prior to 9/11?!

You made the claim that the towers were designed for the fires as a result of a plane impact. You supported that statement with an ambiguous quote from Skilling where you have to "interpret" what you "think" he "seemed" to have meant.

I supplied a quote from Robertson that clearly states that no designs were incorporated handle the resultant fires due to a plane impact.

I'm not playing these games with you. You made a claim and it was shown to be incorrect.

How is the quote by Skilling ambiguous at all? He clearly states that in his opinion, the resulting fire would kill many people, but it could not destroy the steel structure.

 

[Gamolon]

How is the quote by Skilling ambiguous at all? He clearly states that in his opinion, the resulting fire would kill many people, but it could not destroy the steel structure.

If Skilling's statement was NOT ambiguous, then why are you speculating in your quote below? See bolded text.

They both say the impact of a jet airliner was considered. If they made no specific calculations what exactly would happen in the fires following the impact, it would seem to be because they thought it was self-evident the building would survive those fires. When you consider Skilling's wording, "The building structure would still be there", it seems to me he didn't even consider fire-induced collapse a remote possibility. And if you read the article further, he clarifies he believed that the only thing that could bring the towers down was controlled demolition by a "top expert" in that field. Now, I'm not trying to posthumously claim Skilling to be on my side. Nobody knows what he would have thought of the collapses if he had been alive in 2001. But if a lead engineer on the WTC project didn't consider it plausible that plane impact and fires could seriously damage the building, let alone completely destroy it, it seems absurd to say the fires were much worse than what the building was designed to withstand.

I have Robertson's quote. It's clear and to the point. I don't need to use the words "if" or "it seems".

 

[benthamitemetric]

As is typical for these threads, the truther "perspective" on the topic is needlessly based on speculation. James Glanz published City in the Sky: The Rise and Fall of the World Trade Center, a magnum opus on the design of the towers, way back in 2014. To lay to rest the ignorant arguments about what the tower was and was not designed for, here is an extended excerpt of the subsection that details the extent to which the buildings were designed to withstand airplane impacts:

In short, there is no evidence that any of the engineers involved ever undertook any rigorous analysis of the survivability of the buildings in a fire caused by an airline strike (or any fire of a similar magnitude).

Henkaa: speculating that someone may have agreed with what you want to be true is not an argument. The factual record on this point is clear.

 

[Henkka]

If Skilling's statement was NOT ambiguous, then why are you speculating in your quote below? See bolded text.


I have Robertson's quote. It's clear and to the point. I don't need to use the words "if" or "it seems".

Uh, I'm hedging my language a little because I'm talking about a dead person who obviously can't log on here and clarify exactly what he meant. So obviously there is a degree of interpretation. But do you disagree with my interpretation that Skilling thought fire could not destroy the underlying structure? And it's not some great mystery why he would think that, considering no other tall, steel-framed building had ever collapsed from fire before. That interview was even 2 years after the One Meridian fire.

As for your Robertson quote... He said "no designs were prepared" to consider the effects of a fire ensuing from plane impact. That does not mean he or anyone else thought it was remotely plausible the Twin Towers could collapse from fire. FDNY wagered the lives of hundreds of their firemen on that understanding when they sent them running up the steps of the South Tower.

 

[benthamitemetric]

Uh, I'm hedging my language a little because I'm talking about a dead person who obviously can't log on here and clarify exactly what he meant. So obviously there is a degree of interpretation. But do you disagree with my interpretation that Skilling thought fire could not destroy the underlying structure? And it's not some great mystery why he would think that, considering no other tall, steel-framed building had ever collapsed from fire before. That interview was even 2 years after the One Meridian fire.

As for your Robertson quote... He said "no designs were prepared" to consider the effects of a fire ensuing from plane impact. That does not mean he or anyone else thought it was remotely plausible the Twin Towers could collapse from fire. FDNY wagered the lives of hundreds of their firemen on that understanding when they sent them running up the steps of the South Tower.

Who cares what anyone thought if those thoughts were not based off of actual rigorous analysis and study? This is third or fourth thread that is now driven by your incredulity alone: because these events were unprecedented and surprised many people, therefore conspiracy! Because everyone knows that people always know everything and are never surprised by events! As if this fallacious and nonsensical line of argumentation weren't bad enough, you make it worse by not even doing the work to figure out exactly what people actually knew or the extent to which they were actually surprised.

 

[Henkka]

In short, there is no evidence that any of the engineers involved ever undertook any rigorous analysis of the survivability of the buildings in a fire caused by an airline strike (or any fire of a similar magnitude).

Why not, if they considered the airline strike? Was it incompetence? Laziness? Stupidity? These men don't strike me as any of those things.

 

[Gamolon]

As for your Robertson quote... He said "no designs were prepared" to consider the effects of a fire ensuing from plane impact. That does not mean he or anyone else thought it was remotely plausible the Twin Towers could collapse from fire.

You're avoiding the main point I made.

YOU made a claim that the towers were designed to withstand resultant fires due to a plane impact. You're basing this on speculation alone. It has nothing to do with anyone thinking a total collapse was possible.

Read the excerpt posted by benthamitemetric above. Couple that with Robertson's quote.

 

[benthamitemetric]

Why not, if they considered the airline strike? Was it incompetence? Laziness? Stupidity? These men don't strike me as any of those things.

What difference does it make to the actual question of this thread? You were wrong. They did not do the analysis and thus could not have had an informed view as to what the effects of a post-crash fire would be.

 

[Henkka]

YOU made a claim that the towers were designed to withstand resultant fires due to a plane impact. You're basing this on speculation alone. It has nothing to do with anyone thinking a total collapse was possible.

Okay, fine, fine... Would you be ok with the wording that the designers, who were extremely competent and experienced in their field, assumed the building would withstand that fire with no major damage?

 

[Mendel]

How is the quote by Skilling ambiguous at all? He clearly states that in his opinion, the resulting fire would kill many people, but it could not destroy the steel structure.

Engineers have been wrong before. (In fact, that's why AE911 rejects the NIST report.)

Before 9/11, not a single tall building had ever collapsed from fire, no matter how severe

And this explains why he was wrong.

If no things ever happened that had not happened before, we never would see new things. (You might as well claim there never was a moon landing.) And when we do, we're often unprepared.

Do you really want to claim NIST is fallible, but Skilling isn't? On what evidence?

 

[Mendel]

That does not mean he or anyone else thought it was remotely plausible the Twin Towers could collapse from fire. FDNY wagered the lives of hundreds of their firemen on that understanding when they sent them running up the steps of the South Tower.

Do you have evidence to support that claim?

 

[Mendel]

Why not, if they considered the airline strike? Was it incompetence? Laziness? Stupidity? These men don't strike me as any of those things.

They didn't have the tools to do it.
And they were not required to do it.

Enough reason for dedicated, smart, competent people not to.

 

[Mendel]

Okay, fine, fine... Would you be ok with the wording that the designers, who were extremely competent and experienced in their field, assumed the building would withstand that fire with no major damage?

ONE designer.
And he erred, understandably.

Because nobody "competent and experienced in their field" could have performed such an analysis at that time. (Consider how long it took NIST 30 years later, and what additional data they needed, even ex post facto.)

 

[deirdre]

Okay, fine, fine... Would you be ok with the wording that the designers, who were extremely competent and experienced in their field, assumed the building would withstand that fire with no major damage?

i disagree they implied no major damage. but otherwise, sure. and The Titanic is unsinkable.

 

[Henkka]

This is third or fourth thread that is now driven by your incredulity alone: because these events were unprecedented and surprised many people, therefore conspiracy!

By they way, here's what I've learned from this thread and the one about the plane hitting higher:

1) Six floors dropping will destroy over 100 floors below

2) To drop the six floors, all you need to do is douse a few floors in fuel, and then set them on fire

Who knew the Twin Towers could be demolished so economically... You're right I'm incredulous, but it's only because the things you guys believe are so laughably absurd.

 

[benthamitemetric]

By they way, here's what I've learned from this thread and the one about the plane hitting higher:

1) Six floors dropping will destroy over 100 floors below

2) To drop the six floors, all you need to do is douse a few floors in fuel, and then set them on fire

Who knew the Twin Towers could be demolished so economically... You're right I'm incredulous, but it's only because the things you guys believe are so laughably absurd.

Well, now you know, and since you can't articulate an actual reason why the foregoing (ignoring that you insist on using an overly-simplified strawman for pt. no. 2) is wrong, you should also understand. But not everyone can understand such things, I guess. In any case, it's a good thing that large commercial aircraft hitting skyscrapers is such a rare event.

 

[Gamolon]

2) To drop the six floors, all you need to do is douse a few floors in fuel, and then set them on fire

It's the combination of damage to the structure from the impact itself an then the resultant fires affecting the already damaged structure.

 

[Jeffrey Orling]

By they way, here's what I've learned from this thread and the one about the plane hitting higher:

1) Six floors dropping will destroy over 100 floors below

2) To drop the six floors, all you need to do is douse a few floors in fuel, and then set them on fire

Who knew the Twin Towers could be demolished so economically... You're right I'm incredulous, but it's only because the things you guys believe are so laughably absurd.

A few gallons of fuel? How do you account for the plane hitting with almost full tanks?

 

[Henkka]

This is just stupid.

It's the combination of damage to the structure from the impact itself an then the resultant fires affecting the already damaged structure.

Well, take it up with econ41, Jeffrey Orling and FatPhil, who all seem to have implied the structural damage from the impact was not actually necessary. Hopefully I'm not misinterpreting anyone here... See Mendel's post #9 and the responses to it, posts #11 and #13.

 

[Jeffrey Orling]

Well, take it up with econ41, Jeffrey Orling and FatPhil, who all seem to have implied the structural damage from the impact was not actually necessary. Hopefully I'm not misinterpreting anyone here... See Mendel's post #9 and the responses to it, posts #11 and #13.

My thinking is that the initial impact damage from the plane strikes were not fatal. I think one can assume if there were no fires the towers would have stood. The damage was contributory, but not necessary or sufficient alone to collapse the tower.
Engineers know that fires can be fatal to steel frames and why passive measures are taken... spray on insulation and sprinkler systems. These measures are sufficient to deal with fires or typical contents burning.

 

[Gamolon]

Well, take it up with econ41, Jeffrey Orling and FatPhil, who all seem to have implied the structural damage from the impact was not actually necessary. Hopefully I'm not misinterpreting anyone here... See Mendel's post #9 and the responses to it, posts #11 and #13.

So when econ41 said this below to your question of "Is it your position that the WTC towers could have collapsed from fire alone, without plane impact?", you ignored the answer and instead took it as "yes"?

No!

 

[Henkka]

So when econ41 said this below to your question of "Is it your position that the WTC towers could have collapsed from fire alone, without plane impact?", you ignored the answer and instead took it as "yes"?

Yeah, as I said in my first reply to this thread, his answer came off as "Yes, but" to me. Mendel's question in post #9 really hit at the heart of what I was asking, but econ41 seemed reluctant to entertain a hypothetical where similar fires were set some other way than a plane hitting the building.

 

[Mendel]

1) Six floors dropping will destroy over 100 floors below

Then this will surprise you:

Source: https://m.youtube.com/watch?v=y97rBdSYbkg

Any child setting off a domino chain reaction is not incredulous about it, why were you?

Mendel's question in post #9 really hit at the heart of what I was asking, but econ41 seemed reluctant [...]

No, @econ41 simply hasn't posted since then.