Thread: 9/11 was an inside job

Originally Posted by Latindancer

Originally Posted by ENT

there's no way that the light, carbon fibre re-enforced, plastic and aluminium skinned wings could have just sliced through the steel girders forming the outer ring of the tower, and the momentum of the mass of aircraft would have decreased dramatically upon impact and again, the plastic plane could never have cut through the core columns of the tower and then emerge, without losing any speed at all, out the other side of the tower.

Two CNN videos even show what appears to be the undamaged plastic nose section bursting out of the South tower as the tower explodes!

Once again you fail to understand the basic physics of crashes.

Besides which, aircraft- grade aluminum is an alloy, extremely strong, and rivals steel.

Hell, do you ever spout some garbage when yodelling on about physics!

Did you get that out of "Popular Mechanics" or your twelfth grade physics?

WTC outer steel cladding yield strength was 36,000 psi, inner core columns - 150,000 psi, and ultimate strengths ranging from 50,000 - 200,000 psi.

Aluminum yield strength is 15,000 - 70,000 psi, and ultimate strengths ranging from 30,000 - 90,000 psi.

So, steel is stronger than aircraft grade aluminum or any aluminium for that matter, which is 1/2 as strong, at best but 1/3 as heavy as steel.

Bear in mind that the aircraft grade aluminium skin was only a couple of times thicker than that of a coke can, and had very little structural strength so had to be supported on an airframe of carbon fibre and further aluminium, which flexes on impact, buckling the plastic cladding which of course shatters and crumples on impact with a denser object such as a steel framed concrete building.

Steel in WTC construction
"The WTC structural plans specified steels that began at a minimum yield strength FY = 36 ksi and increased from FY = 40 ksi to FY = 85 ksi in 5 ksi (34.5 MPa) increments. Corner elements in the exterior wall often used FY = 100 ksi steels. Contemporaneous construction documents indicate that the lowest strength exterior wall column steels were supplied to the ASTM A 36 standard, but all the steels with strengths above that value conformed to proprietary grades that the Port Authority of New York and New Jersey, the building owner, authorized. Yawata Iron and Steel, now Nippon Steel, supplied most of the steel plate for the exterior wall columns. The plate that faced the interior of the building usually came from a domestic mill, however."
The Role of Metallurgy in the NIST Investigation of the World Trade Center Towers Collapse