The reason the WTC collapsed was not because the crash weakened the structure. The planes were full of jet fuel for the trips across the country. (This is said to be part of the terrorist plan.) The high-temperature of the burning jet fuel compromised the structural integrity of the steel, which is why the building collapsed. If the jets were relatively empty, like they would be on a trip from Boston to NY the fires would not have lasted as long and the building would probably still be standing. The WTC towers were designed to withstand impacts from large aircraft (707? 727?) and the steel was designed to withstand heat for prolonged periods of time.
The hydrogen fuel would not burn as hot and also would evaporate very quickly.
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The reason the WTC collapsed was not because the crash weakened the structure. The planes were full of jet fuel for the trips across the country. (This is said to be part of the terrorist plan.) The high-temperature of the burning jet fuel compromised the structural integrity of the steel, which is why the building collapsed. If the jets were relatively empty, like they would be on a trip from Boston to NY the fires would not have lasted as long and the building would probably still be standing. The WTC towers were designed to withstand impacts from large aircraft (707? 727?) and the steel was designed to withstand heat for prolonged periods of time.
The hydrogen fuel would not burn as hot and also would evaporate very quickly.