The fires spread and intensified long after the jet fuel was burnt off. Plenty of video of the downwind south and east sides show fire intense and spreading. The west sides too. Shortly prior to collapse, both towers displayed an increase in the volume and velocity of the smoke, which is hot enough to damage steel on it's own. In firefighting manuals, that is referred to as black fire, which predicts imminent auto-ignition with explosive potential.
1800f was measured in the Towers.
Read about black fire and the properties of smoke in my above post.
Undo what Wilson did
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