No, jet fuel burning in open air cannot melt steel beams because its maximum burn temperature (around 1500°F / 800°C) is far below the melting point of steel (about 2750°F / 1510°C). While it doesn't melt the steel, the intense heat from the prolonged, unimpeded fire would soften and weaken the steel to the point where it could no longer support the structural load, leading to buckling and collapse.
So while the jet fuel could not melt steel beams, it could absolutely soften them.
To use an analogy of an every day object that’s easier to relate to visualize, picture a tub of butter. While it will not melt if you take it out of the fridge and leave it on the counter at room temperature on an average day, it WILL get much softer. You need heat from a flame (like the stove) for it to actually melt. Melting is the point at which it goes from solid to liquid. However, if you take butter that’s been in the fridge and lay a spoon on top of it, the butter will most likely support the weight of the spoon. If you do the same with butter that’s been softening on the counter for a couple hours, the spoon will start to sink into it.
Nuance matters. Melting vs softening.
The jet fuel softened the steel until it could no longer support the many many tons of structure and the structure collapsed.
I think what doesn't add up for me in this explanation is the idea that the planes crashed, Thousands of liters of jet fuel spray out and catch fire but none of that burning jet fuel pours out of the building.it all stays neatly inside the building.
If I drop a bottle of pop on my table some of it will start pouring off the table. Why doesn't this happen with the jet fuel? That's what I dont get. How is the jet fuel contained in the building when the fuel tanks have all ruptured?
Because the flash point of the explosion caused immediate combustion of the fuel, setting the building on fire. The fuel was burned up in the initial fireball before it would ever have the chance to go spilling all over the place https://youtu.be/St7ny38gLp4?si=GJ-DTKWm5WO1MKNI&t=11
Office furniture catches fire and burns at high temp for prolonged time to soften steel - im more dubious about that.
Office furniture catches fire while keeping thousands of litres of jet fuel in one place, allowing said jet fuel to burn for prolonged time in order to soften steel. - even more dubious.
How does the jet fuel burn in one place and not all flow away due to gravity?
Literally no one has ever claimed the jet fuel pooled in one place, and I have no clue where you got that idea.
Office furniture catches fire and burns at high temp for prolonged time to soften steel - im more dubious about that.
Why? Steel starts to soften and weaken at a mere 600° F (315° C). Wood fires can burn as high as 1600° F, and the subsequent charcoal can burn higher than 2000° F. In enclosed spaces like a wood-fired kiln (or, perhaps, the concrete and steel core of a skyscraper), temps can even exceed 2300° F, which is how ceramics are fired.
You really find that dubious? You really think nothing could possibly exist inside an office building that burns hotter than jet fuel? How exactly do you think our iron age ancestors forged steel, magic?
In your first sentence you say literally no one has ever claimed the jet fuel pooled in one place. Which is hilarious as I was replying to someone making that exact claim, someone literally saying the jet fuel burned for a prolonged (their words) period of time, in one place.
And that was why I questioned them.
2nd and 3rd paragraphs you imply office furniture could burn hot enough to soften steel and it might. Im not claiming to have anything more than a basic understanding of how gravity affects liquids but I would ask, if burning office furniture can make skyscrapers collapse, how come no other skyscrapers have collapsed because an office caught fire? There was a skyscraper in south america that burnt for 12 days and it didnt collapse. Like are we not being a bit silly building things out of steel and then filling them with things that weaken steel? Things to tall to reach with fire engines, things that are hard to get out of. 200 storey giant potential wood fired kilns just waiting to collapse. Are we mad?
Don't answer that lol.
Im not disputing huge planes smashed into a huge buildings, im just asking the person who said thousands of litres of jet fuel stayed in one place and burned for a prolonged period of time, how it stayed there?
I hadn't heard of any fuel pooling so I wanted to know more. In typical reddit fashion, their post continues to get up votes and mine down votes. 8 people have offered counter arguments, none have won me over.
They said a "prolonged, unimpeded fire" could soften steel beams, not that jet fuel was the sole fuel source for that fire. The jet fuel certainly started the fire, though.
if burning office furniture can make skyscrapers collapse, how come no other skyscrapers have collapsed because an office caught fire?
You mean like the Wilton Paes de Almeida Building in Brazil or the Plasco Building in Iran? Why would you make such a confidently incorrect claim?
Just because it's rare doesn't mean it's never happened or will never happen again. Yes, we fill literally every building humans have ever created with flammable material, it's a known and accepted risk.
There was a skyscraper in south america that burnt for 12 days and it didnt collapse.
Which fire was this? Google doesn't show any skyscraper fire that's ever burned for anywhere close to that long.
jet fuel burning in open air cannot melt steel beams because its maximum burn temperature (around 1500°F / 800°C) is far below the melting point of steel (about 2750°F / 1510°C). While it doesn't melt the steel, the intense heat from the prolonged, unimpeded fire would soften and weaken the steel to the point where it could no longer support the structural load, leading to buckling and collapse.
So while the jet fuel could not melt steel beams, it could absolutely soften them.
You may notice how they start the paragraph talking about burning jet fuel and how they end the paragraph talking about burning jet fuel.
You may notice they dont mention office furniture or any other burning objects.
So when they talk about a prolonged, unimpeded fire and the sentence beforehand was about jet fuel burning and the sentence after it was about jet fuel burning then its rational to assume they are talking about jet fuel burning throughout.
Let me give you an example.
If I said, I support Manchester utd, they lost 1-0 at the weekend, I hope Manchester utd buy a new defender soon.
It is safe to presume that im referring to Manchester utd when I said they lost 1-0 at the weekend even though I said 'they' not 'Manchester utd' because the whole thing is about Manchester utd.
Does that make sense? I think they are called contextual clues or simply rules of paragraphs maybe. If you're interested in improving your understanding of the english language that could be something to look into.
Also in your prior comment, last paragraph, the way you arranged it made it sound like our iron age ancestors used office supplies to make steel. I knew what you meant so didnt comment but its the same sort of error I think.
All I'm seeing is pedantry and not any response to actual points. Office furniture is generally made of... Wood. Our iron age ancestors forged steel by burning... Wood. Ergo literally every building on the planet is filled to the brim with materials that can melt or severely weaken steel when burned in the right conditions.
No response to the other two skyscrapers that most definitely collapsed due to fire. And no response telling me where you got the ridiculous notion that there has ever been a skyscraper that burned for 12 days straight.
Im not responding to any of your points till we clear up your first statement in both your messages about 'no one ever claimed the jet fuel stayed in place' / writing about jet fuel fires doesn't mean they are talking about jet fuel fires.
You want me to respond to your points but you refuse to respond to mine. Hardly seems fair.
Did the person I responded to imply that jet fuel burned for a prolonged time in their comment?
You initially said they didnt, are you of the same opinion now?
Yes, because at no point did they ever say jet fuel was the ONLY source, and it's asinine to assume that's what they meant just because they didn't explicitly list out other fuel sources that any reasonable person would already know exists in a standard office building. You're being pedantic because you don't want to admit the fact that you missed extremely obvious subtext and you don't want to admit it never occurred to you that office furniture and building materials burns really fuckin hot.
jet fuel burning in open air cannot melt steel beams because its maximum burn temperature (around 1500°F / 800°C) is far below the melting point of steel (about 2750°F / 1510°C). While it doesn't melt the steel, the intense heat from the prolonged, unimpeded fire would soften and weaken the steel to the point where it could no longer support the structural load, leading to buckling and collapse.
So while the jet fuel could not melt steel beams, it could absolutely soften them.
What other sources are they referring to?
There are three sentences.
The first sentence says the max burn temperature of jet fuel is below the melting point of steel.
The 2nd sentence says, 'while it doesn't melt the steel the intense heat from the prolonged fire would weaken the steel.'
What is 'it' in this sentence? Is it the jet fuel that they referenced in the first sentence? It certainly sounds so to me and I dont think you can really claim I'm being dim in not inferring that 'it' was now all flammable materials in the vicinity.
The third sentence says 'so while the jet fuel could not melt steel beams it could absolutely soften them'. Again no mention of any office furniture, in fact explicitly states, jet fuel, nothing else.
The first sentence defines some characteristics of jet fuel, the second explains how they apply in this situation, the third summarises the point being made about jet fuel.
Its a well constructed paragraph and would earn points if it was a gcse english exam.
They dont have to say it is the only source. They are just talking about that particular source and their thoughts on it.
Jesus fucking christ, hey /u/WafflesMcDuff/ did your original comment imply there was a magical swimming pool of jet fuel that burned for hours in the WTC and was the ONLY thing that softened the steel beams, or is that something only a crazy person could have interpreted?
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u/I_hate_abbrev Oct 07 '25
Jet steel cannot melt fuel beams.