The Twin Towers did perform well on 9/11...although No. 1, the second tower hit, didn't quite last 60 minutes -- it fell in 56, because it was hit lower down (adding to the weight of the damaged area) and at an angle, nicking an edge of the building, that compromised its structural integrity even apart from the impact and fires. The first tower struck lasted longer (102 minutes) because it was hit higher up and squarely in the middle, not along the edge as with the second impact.
However, I don't agree with your statements,
It is a misunderstanding, that a building should keep standing after a fire. There is just the rule, that while burning, a building has to stand the time necessary to evacuate the buidling.
No one says a building "should" keep standing after a fire, but neither is there necessarily any reason why it should not. Obviously this depends on the size and nature of both the building and the fire. Besides which, the towers had to deal with more than just a fire -- they had to withstand and survive the impact of the planes crashing into them.
There is also no "rule" that a building has to stand long enough to evacuate everyone. While this may be an incidental goal no one can guarantee how long it will take to evacuate a building, especially one that's been damaged or compromised by some catastrophe. This non-existent "rule" could not possibly be guaranteed, designed or prepared for beyond some very broad structural guidelines.
Unluckily on 9/11 the upper stores could not be evacuated and some stupid folks decides, that the people below the impact should stay in the offices instead of trying to walk down.
This is not quite accurate. The plane that hit WTC #2 (the first building struck) severed all the elevators and stairwells below the impact zone. This made it impossible for anyone trapped above that zone to get down (which is why many people jumped rather than burn to death). But the order to evacuate that building was given within about five minutes; I know someone who worked on the third floor (luckily for him) who got down and out without issue, as did most people who could evacuate the building. (This man also heard the impact of bodies hitting the plaza behind him as he left -- he says he knew what it was and could not turn around to look.) Because it was hit earlier and lasted longer, most people in that building below the impact zone got out.
The problem was in WTC #1, the second tower hit. There was 17 minutes between the time the first tower was hit at 8:46 and the second tower was struck at 9:03. In that time many people in WTC #1 did indeed take the elevators to the lobby as a safety precaution. You're correct, some idiot in the Port Authority (which operated the WTC) told people to return to their offices, and many did. This was an unbelievably stupid decision, since rudimentary safety precautions would dictate evacuating all structures adjacent to a burning one. Apparently this decision was made reflexively, to reduce pedestrian congestion outside when emergency services were en route, but it was an idiotic one, even without knowing that the second tower was about to be attacked. Many of the people who returned to their offices and were above the impact zone in the second tower spent their last minutes calling loved ones and being ruefully angry at themselves for going back up. Of course, after the second impact Tower #1 was ordered evacuated but it was too late for many, and of course they had less time to get out, though no one could know that.
The big difference is that because the second plane struck Tower 1 at an angle it failed to sever one of the three staircases leading down, so unlike in Tower 2 (the first one hit), where there was no way down and everyone above died, ten people from above the impact zone in #1 were able to get down and out because of that one remaining stairway.
The fact that they were able to walk more than 60 stories down, through a heavily damaged portion of the building, in under an hour before the building collapsed shows that in most respects the buildings were well-designed. But there is simply no way anyone can guarantee how long a building will stand during a fire or how long it will take to evacuate it. You can build with certain parameters in mind but no building can ever be designed or built with an absolute certainty as to how it will behave in a catastrophe. When the Trade Center was bombed in 1993 it took over three hours to get everyone out, even though while there was smoke the buildings themselves were intact. They did institute improvements in evacuation procedures after that.
To the WTC: I live in New York and have three friends who were at the WTC on September 11. One worked in Tower #2, who I mentioned. Another worked in Tower #1 (the second one struck) but was just arriving when it was hit, so he never went inside; his office was on the 96th floor and everyone in it was killed. The third worked in #7, the last of the seven buildings in the WTC complex to collapse, around 5 that afternoon. When the first plane struck he and his office manager ordered everyone out (they were on the 23rd floor I believe) and themselves stayed on for about 45 minutes until deciding to get out. But no one interfered with their evacuation order and the buildings were formally ordered evacuated within a few minutes anyway. He got out about five minutes before the first collapse at 9:59.
reply
share