Here's something to remember the next time someone tries to tell you that fires from the jet fuel brought those (THREE!) buildings down: ENGINES.
We are surrounded in our world by vehicles that use internal combustion engines. These now-essential, greatly taken-for-granted devices have been in use by the human race for over a century and a half. They are everywhere - cars, trucks, buses, trains - and oh yes, planes. For the better part of the last century and a half, most engines have been made either entirely or partially out of steel.
From the
Wiki page:
"The upper operating temperature of a terrestrial engine is limited by the thermal stability of the materials used to construct it."
"Most steel engines have a thermodynamic limit of 37%."
Internal combustion engines work because the temperature of the burning fuel inside is lower than the temperature required to melt the steel that contains it.
Therefore: fuel fires do not melt steel. Period.
If fuel fires melted steel, no car you see driving down the road would work. No train would move. No plane would even get off the ground, much less fly into a building.
It was not Al Qaeda who told the world the insane lie that fuel fires melt steel. It was our government under the administration of George W. Bush.
This is the simplest, most accessible-to-the-layman explanation possible for the need to re-investigate the events of 9/11/01.