In article ,
pyotr filipivich wrote:

After a Computer crash and the demise of civilization, it was learned
"cncfixxer1" wrote on Fri, 02 Nov 2007 15:35:54
GMT in rec.crafts.metalworking :
Has to do with volume and speed of air ... the same as bellows that were
used in blacksmithing.

Years ago a neighbors house burned down and the metal beams actually melted
... not twisted but melted..
That was from just wood and air

Stainless steel grills are suppose to stand up to bbq fires. They
do, but not when the fire is augmented with coal and a forced draft.

It needn't even require forced draft. Some African blacksmiths use
charcoal fired forges made of tile pipe hanging from a tree limb or
another handy support.

The pipe has a grate and is open bottom to top with a hole in the side
for the smith to insert workpieces.

Just the natural draft from the heated air up the pipe drawing in cool
air at the bottom can keep the forge hot enough to burn/melt steel.

Way I figure it, the natural draft from the fires in the two main WTC
buildings was probably more than enough to generate enough heat to
weaken the floor trusses. When one gave way, everything above that
slammed into those floors and all of that pancaked into the lower floors.

No conspiracy needed, just lots of fuel and natural draft from the
chimney effect of a tall building with big holes in its sides.