Engineering issues aren't at the top of anyone's mind, I know, but this structural factor offers an interesting contrast with what happened to the Empire State Building (relatively little) when it was hit by a B-25 in 1945.
The following is from one web source on this:
Mitchell Bomber vs. Empire State Building
© Copyright 1999, Jim Loy
On Saturday, July 28, 1945 (a few days before the Atomic bomb was dropped on Hiroshima), a B-25 Mitchell bomber ran into the Empire State Building, then the tallest structure in the world. The bomber, piloted by Lt. Colonel William F. Smith, was flying under clouds, from Massachusetts to New Jersey. At about 10 A.M., the bomber hit the 79th floor, killing the three men aboard instantly. One of the two engines went through the building and out the other side, and through the roof of a 20-story building on the other side of 34th Street, starting a fire. The other engine, and part of a landing gear entered an elevator shaft and fell to the basement, onto an unoccupied elevator. Two women in another elevator fell 75 stories, and survived with serious injuries. Eleven people died in the fire on the 79th floor.
Why didn't the Empire State Building fall down? Well, an airplane (even a bomber) is fairly insignificant compared to the massive steel and concrete building. And, as explained by Levy & Salvadori, in Why Buildings Fall Down, the Empire State Building had built-in redundancy. No single beam held up the building. As it turned out, none of the vertical beams was severed, although two of them were struck by wings.
On May 20, 1946, another military airplane, lost in fog, hit the 58th floor of a building on Wall Street, killing the five men on board, and injuring no one else.
(end)
Carl
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