Quote:
Originally Posted by finnbow
Yep. Furthermore, the planes hit a number of floors below the top of the building. As the heated steel yielded on these floors, all the weight above it comes crashing down with impact forces which domino as the weight of more and more collapsed floors have to be borne by the steel below it.
This phenomena is somewhat akin to the 1987 L'Ambiance Plaza collapse in Bridgeport, CT. I was involved in reviewing the forensic engineering analysis of this catastrophe and drafting the Federal regulations to prevent recurrence. |
The jet that hit the North Tower flew in perpendicular to the tower's northeast face, and impacted around the center of the 95th floor, producing an impact gash that extended from the 92nd to the 98th floor. Most of the plane apparently lodged in the tower's core structure, the only piece of aircraft to emerge from the opposite side being a dense piece of landing gear. The burning jet fuel, atomized on impact, spilled out of the impact gash and through broken windows on the southeast side.
In contrast, the jet that hit the South Tower, 18 minutes later, veered to the right just before impact and hit the rightmost third of the tower's southwest wall, producing an impact gash that extended from the 78th to the 94th floor.