For Those Who Say "Jet Fuel Can't Melt Steel Beams"

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Greenman

Lifer
Oct 15, 1999
20,384
5,129
136
Patience wears thin around here when idiotic "theories" are posted about a planned demolition of any of these buildings. Everyone around here is intelligent enough to understand these demolitions could not possibly be done on a covert level, one MUST drill/jackhammer into structural members for weeks/months prior AND wire it all up to work.
Totally get it. But when the discussion turns to personal attacks it's all done. Everyone on my ignore list is there for one reason only, they can't repudiate an argument without a personal attack. I find that contemptuous, and annoying.
 

zinfamous

No Lifer
Jul 12, 2006
110,597
29,231
146
Apologies, my mistake re where the collapse began. But doesnt change the fact the official report is still at odds with 1000s of architects and engineers who do not agree with the NIST findings and challenge them to this day. Pancake theory or not, the inconvenient little detail that the owner of WTC 7 said the building was "pulled" remains.

jesus fucking christ
 

MtnMan

Diamond Member
Jul 27, 2004
8,751
7,867
136
This again? it doesn’t need to melt… it doesnt need to burn… it just needs to become pliable and the temperature for that is much much lower…
This ^^^

Since the first time I heard this bullshit, I understood that to fail it doesn't have to "melt" to fail, only reach a temperature that compromises it strength.

Structural steel begins to soften around 425 °C (800 °F) and loses about half of its strength at 650 °C (1200 °F).
 
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yottabit

Golden Member
Jun 5, 2008
1,365
229
116
This ^^^

Since the first time I heard this bullshit, I understood that to fail it doesn't have to "melt" to fail, only reach a temperature that compromises it strength.

Structural steel begins to soften around 425 °C (800 °F) and loses about half of its strength at 650 °C (1200 °F).

The thing is, the steel did melt though at least in some cases.

There were multiple eyewitness accounts of molten metal at ground zero. Some of that may have been aluminum and copper, but some was certainly steel or components of it.

The whole conspiracy theory started from images like this: https://en.m.wikipedia.org/wiki/File:9_11_underground_fires_Hotslag-300x215.jpg#mw-jump-to-license

Now despite crusty 200px resolution images that may or may not show molten steel, damage to some of the steel beams was consistent with melting. There are many witness accounts of slag and I believe more photos.

This is why the conspiracy nuts hooked onto "It must be thermite!!!!" Since jet fuel without an oxidizer probably can't liquidify steel. Not that I'm defending the conspiracy nuts but it is a bit puzzling. I didn't realize there were even dumber people that hooked onto the phrase and thought it implied why the buildings couldn't have collapsed.

Anyway the answer seems to be FEMA posted an interesting report showing exactly how the fires DID "liquify" the steel at lower temperatures than normally thought possible, and not due to a traditional "melting" process

Here's a FEMA link https://www.google.com/url?sa=t&sou...wQFnoECAkQAQ&usg=AOvVaw0rXzD2s_HmHe3liPhbR0tB

It's very interesting to me. Mat sci is not my strong suit but my attempt at converting that into laymens terms would be it seems to me that long exposure to corrosive combustion gasses began to separate and expose the alloying elements of the steel (such as iron nickel and copper) which have a lower melting point. Which then melted into a mixture which penetrated further into the steel and became a viscous cycle of sorts

Most of the molten metal was probably from Wtc7. Wtc7 burned unrestricted. It was moreso a normal office fire than fueled by jet fuel, but the collapse of the other Wtc towers knocked out the water supply to the sprinklers so the temps were extreme. It's believed the building collapsed due to the tremendous thermal expansion which strained the joints between floors.
 

Zorba

Lifer
Oct 22, 1999
14,553
9,930
136
Yeah, like a certain apartment complex near Miami.

These collapses via shoddy construction / maintenance are too common for you to gaslight us into thinking anything is out of the ordinary in #7's collapse.
Considering implosion works by knocking out critical supports and then letting gravity take care of the rest. Why are people surprised when you have critical supports fail and gravity takes over that it looks a lot like an implosion?

Also I'd like to see videos of any building that was actually imploded top down.
 
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Vic

Elite Member
Jun 12, 2001
50,415
14,305
136
300,000 lbs of jetliner carrying 11,000 lbs of kerosene collide with buildings at 625 mph and people are so shocked the buildings fell that they have make up bizarre conspiracy theories?
It is a testament to their engineering that the buildings stood as long as they did, and didn't collapse on impact.
 

brycejones

Lifer
Oct 18, 2005
26,157
24,093
136
300,000 lbs of jetliner carrying 11,000 lbs of kerosene collide with buildings at 625 mph and people are so shocked the buildings fell that they have make up bizarre conspiracy theories?
It is a testament to their engineering that the buildings stood as long as they did, and didn't collapse on impact.
More like 70,000 to 80,000 lbs if jet fuel when they hit.
 

Zorba

Lifer
Oct 22, 1999
14,553
9,930
136
300,000 lbs of jetliner carrying 11,000 lbs of kerosene collide with buildings at 625 mph and people are so shocked the buildings fell that they have make up bizarre conspiracy theories?
It is a testament to their engineering that the buildings stood as long as they did, and didn't collapse on impact.
I think it was around 80K of fuel when they hit and about 300 mph, IIRC. Still the amount of energy is insane.

Edit: Looked it up. AA 11 was ~10,000 gallons, or about 66K pounds and 465 mph. UA175 was 9,100 gal, or about 60K pounds and >500mph.
 
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Vic

Elite Member
Jun 12, 2001
50,415
14,305
136
I think it was around 80K of fuel when they hit and about 300 mph, IIRC. Still the amount of energy is insane.
Honestly, I couldn't remember the numbers it's been so long. I just remember that insisting that a building should remain standing after being impacted by a fast-moving widebody with full fuel tanks is still one of the stupidest arguments I've ever heard.

Edit: doublechecked and it's 11k gallons which is about 80k lbs. My bad.
 
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Vic

Elite Member
Jun 12, 2001
50,415
14,305
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One good thing did come out of 9/11. Which is that planes don't get hijacked anymore. And that's not just because of the increased security measures. It's also because would-be hijackers know that ransom demands won't work when the passengers have no expectation of survival.
 
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Zorba

Lifer
Oct 22, 1999
14,553
9,930
136
One good thing did come out of 9/11. Which is that planes don't get hijacked anymore. And that's not just because of the increased security measures. It's also because would-be hijackers know that ransom demands won't work when the passengers have no expectation of survival.
Yup, any one attempting now gets a beat down and has. Planes also are much more full than they were in 2001, making it that much harder.
 
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Vic

Elite Member
Jun 12, 2001
50,415
14,305
136
On that note, I remember having to defend why I always order a double Jack and coke before boarding a flight. Look, if I'm going to get on a machine that travels 6 miles high in the sky at 600+ mph carrying thousands of gallons of highly combustible fuel, the entire outcome of which I have no control over, then I'm gonna need a shot first, thank you very much.
 

BUTCH1

Lifer
Jul 15, 2000
20,433
1,769
126
Honestly, I couldn't remember the numbers it's been so long. I just remember that insisting that a building should remain standing after being impacted by a fast-moving widebody with full fuel tanks is still one of the stupidest arguments I've ever heard.

Edit: doublechecked and it's 11k gallons which is about 80k lbs. My bad.
Well, "building" could mean a lot of different sizes and mass's as well. Even a widebody jet full of fuel is nothing, (mass-wise) compared to a 1,200 ft steel and concrete structure. Keep in mind that to make code these towers needed to withstand a very high wind level too, sucks that no sprinkler system would be of much use in a raging fire like that.
 

BUTCH1

Lifer
Jul 15, 2000
20,433
1,769
126
Yup, any one attempting now gets a beat down and has. Planes also are much more full than they were in 2001, making it that much harder.
The hijackers planned out routes that were commonly had many vacant seats and were going a long distance so as to be carrying a lot of fuel.
 

BUTCH1

Lifer
Jul 15, 2000
20,433
1,769
126
One good thing did come out of 9/11. Which is that planes don't get hijacked anymore. And that's not just because of the increased security measures. It's also because would-be hijackers know that ransom demands won't work when the passengers have no expectation of survival.
Flight 93 pushed back at 8:00 but was delayed on the tarmac until 8:42, this was why it's passengers got phone calls from family/friends telling them about what had already happened. As the men huddled in the cabin and began hatching a plan to re-take control of the jet a Flight attendant came up to tell them she already had a couple of gallons of boiling water ready to go. Maybe that was the screaming heard on the recorder and think about it, a box cutter vs 1/2 gal or water boiling like a wildcat, I'll take option #2, hard to dodge much in the limited space. God bless this brilliant, smart, and ballsy woman, may you rest in peace, we will not forget you.
 
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Zorba

Lifer
Oct 22, 1999
14,553
9,930
136
The hijackers planned out routes that were commonly had many vacant seats and were going a long distance so as to be carrying a lot of fuel.
Yeah, I mean that would be harder to do today (except for the height of COVID) because the average load factors have gone up over the last 20 years. The load factors were very low on 9/11 because we were already headed into a recession and none of the airlines had pulled back their schedules yet.

The average passengers per flight in August 2001 was 79, in August 2019 it was 95.

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BUTCH1

Lifer
Jul 15, 2000
20,433
1,769
126
Yeah, I mean that would be harder to do today (except for the height of COVID) because the average load factors have gone up over the last 20 years. The load factors were very low on 9/11 because we were already headed into a recession and none of the airlines had pulled back their schedules yet.

The average passengers per flight in August 2001 was 79, in August 2019 it was 95.

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View attachment 50267
IIRC #93 only had around 40-45, I'll have to look it up.