Steel doesn’t have to be heated until it melts. Just until it fails. As stated in the article
@AZVAJKU linked to above
“When steel is heated, it retains its strength up to a temperature of around 350oC. After this point, the steels strength progressively declines until it is deemed totally ‘useless’ at around 1,050oC.”
“Open air” temperature of JP is about 1030c.
It ain’t what people smarter than me say that’s the problem. It’s people taking what people smarter than me said out of context. People smarter than me know that conditions during fires can result in temperatures higher than the “open air” temperatures of the fuel.
JP doesn’t have to reach its adiabatic temperature to heat steel to the point it loses its strength. (Yes, I had to look up adiabatic. I learned a new word.)
I’m not a trained firefighter and don’t know what I don’t know about entering burning buildings
Depending on variant, a 737 can hold 6000 gallons of fuel. Like gasoline, JP doesn’t burn in its liquid state. It must be atomized first. It wouldn’t have atomized and burned off in an instant.
I don’t know if the entire core of the building was saturated with fuel. I think a good part of it was. I don’t think the steel melted before the building collapsed because the steel would have failed long before it melted.
Remember, the North Tower burned almost two hours before it fell and the South Tower close to an hour giving the fire time to heat critical structures to the point of failure. So yes, I believe the fire weakened the structure and caused the collapse.
It’s interesting the architects thought to design the buildings to withstand being struck by an airliner and being set afire by thousands of gallons of jet fuel but didn’t think to design them to pancake in case of structural failure to reduce collateral damage.