ApachePilot said:

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CDUB98 said:

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Sadly, the type of fireproofing they used played a role.

According to one engineering show I watched, they used a type of blown fiberglass, kind of like that loose stuff in our attics that they just blow in.



When the planes hit, the rush of air with them blew that proofing off of the girders in places, exposing the steel directly to the fire.

If they had used the more expensive cementatious proofing, it would have mostly stayed and the towers likely not have fallen.

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When planning they probably never imagined a jet liner hitting the building. We were so naive and safe. I miss those days

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Actually, they did plan, structurally, for a plane hit. IIRC, it was based on either a 707 or 727. Can't remember which.

They built it so it would withstand impact, which, it obviously did from much bigger plane.

The fire case even considered the fuel, again, IIRC. The one piece that they did not expect was for the fireproofing to blow off. No building had ever experience that before, obviously, so they simply did not know what they did not know.

Junior year A&M, an Econ class - everyone's phone goes off about the same time. Class was ending and everyone started talking about what was happening.

Went to Quantitative Analysis class, professor stated (paraphrasing), "I know a lot of important things are happening now; but we need to focus on this subject now."