# Twin Towers Destruction - Could it have been predicted?

**URL:** <https://boards.straightdope.com/t/twin-towers-destruction-could-it-have-been-predicted/640957>\
**Category:** Great Debates\
**Created:** [November 14, 2012, 5:31am UTC](https://boards.straightdope.com/t/twin-towers-destruction-could-it-have-been-predicted/640957 "2012-11-14T05:31:37Z")\
**Posts on this page:** 12\
**Page:** 2

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**Author:** ![dropzone](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dropzone/32/7515_2.png) [@dropzone](https://boards.straightdope.com/u/dropzone)\
**Post date:** [November 16, 2012, 2:50am UTC](https://boards.straightdope.com/t/twin-towers-destruction-could-it-have-been-predicted/640957/21 "2012-11-16T02:50:37Z")

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> [@RickJay](#):
>
> Without knowing what the hell was going on inside I don’t know that you could have KNOWN the towers would collapse. But I think it looked rather possible. I am no structural engineer and didn’t know for sure what was going to happen, but I certainly wasn’t surprised when they collapsed; the damage sure looked like it might be catastrophic.

Originally said by **Me** , a notably uneducated layman, some ten minutes before the first tower collapsed:

That sucker’s gonna drop.

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**Author:** ![BigT](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bigt/32/12044_2.png) [@BigT](https://boards.straightdope.com/u/BigT)\
**Post date:** [November 16, 2012, 6:55pm UTC](https://boards.straightdope.com/t/twin-towers-destruction-could-it-have-been-predicted/640957/22 "2012-11-16T18:55:55Z")

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And here I was sure this was in GD because some Truther hijacked it. This honestly seems like a GQ or at least IMHO.

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**Author:** ![Valgard](https://avatars.discourse-cdn.com/v4/letter/v/7feea3/32.png) [@Valgard](https://boards.straightdope.com/u/Valgard)\
**Post date:** [November 16, 2012, 7:51pm UTC](https://boards.straightdope.com/t/twin-towers-destruction-could-it-have-been-predicted/640957/23 "2012-11-16T19:51:40Z")

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> [@Magiver](#):
>
> the difference between the 2 buildings is substantial. The ESB is filled with steel girders in all directions and they are encased in cement.

Not to mention the difference between the two impacts was substantial. In the first case you had a B25 Mitchell bomber:

empty weight 20,000lbs, max weight 35,000lbs - let’s take the average, about 27,500lbs.  
cruising speed 230mph, landing speed “lower” - it was coming in to land so let’s call it 150mph.

In the second case you’ve got a Boeing 767:

empty weight 315,000lbs (depending on model), max weight up to 450,000lbs (again, depending on model). Terrorists chose flights with maximum fuel and minimum passengers, let’s just take the midpoint and say about 400,000lbs.

Flown in a suicide dive near the VNE (vertical never exceed) speed; IIRC that limit is well over 500mph but let’s use 500mph as a nice round number.

Plugging those values in to figure out the kinetic energy involved, the 767 had about 160 times as much KE as the B-25.

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**Author:** ![Magiver](https://avatars.discourse-cdn.com/v4/letter/m/4491bb/32.png) [@Magiver](https://boards.straightdope.com/u/Magiver)\
**Post date:** [November 16, 2012, 11:43pm UTC](https://boards.straightdope.com/t/twin-towers-destruction-could-it-have-been-predicted/640957/24 "2012-11-16T23:43:42Z")

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> [@Valgard](#):
>
> Not to mention the difference between the two impacts was substantial. In the first case you had a B25 Mitchell bomber:
> 
> empty weight 20,000lbs, max weight 35,000lbs - let’s take the average, about 27,500lbs.  
> cruising speed 230mph, landing speed “lower” - it was coming in to land so let’s call it 150mph.
> 
> In the second case you’ve got a Boeing 767:
> 
> empty weight 315,000lbs (depending on model), max weight up to 450,000lbs (again, depending on model). Terrorists chose flights with maximum fuel and minimum passengers, let’s just take the midpoint and say about 400,000lbs.
> 
> Flown in a suicide dive near the VNE (vertical never exceed) speed; IIRC that limit is well over 500mph but let’s use 500mph as a nice round number.
> 
> Plugging those values in to figure out the kinetic energy involved, the 767 had about 160 times as much KE as the B-25.

:smack: Yah, forgot to even mentions the planes. FYI, VNE stands for Velocity Never to Exceed.

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**Author:** ![Valgard](https://avatars.discourse-cdn.com/v4/letter/v/7feea3/32.png) [@Valgard](https://boards.straightdope.com/u/Valgard)\
**Post date:** [November 16, 2012, 11:51pm UTC](https://boards.straightdope.com/t/twin-towers-destruction-could-it-have-been-predicted/640957/25 "2012-11-16T23:51:41Z")

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> [@Magiver](#):
>
> :smack: Yah, forgot to even mentions the planes. FYI, VNE stands for Velocity Never to Exceed.

Thanks, couldn’t recall it exactly.

The 1993 attempt to blow up the WTC took place when I was in civil engineering grad school. I remember one of my professors, a famous structural engineer, saying something like “There’s no way they’d be able to bring the structure down with a little truck bomb like that”.

IIRC, the plane strike analyses were done less with an actual attack in mind and more with an accident like the B25 hitting the ESB.

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**Author:** ![dropzone](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dropzone/32/7515_2.png) [@dropzone](https://boards.straightdope.com/u/dropzone)\
**Post date:** [November 17, 2012, 4:33am UTC](https://boards.straightdope.com/t/twin-towers-destruction-could-it-have-been-predicted/640957/26 "2012-11-17T04:33:22Z")

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> [@Valgard](#):
>
> The 1993 attempt to blow up the WTC took place when I was in civil engineering grad school. I remember one of my professors, a famous structural engineer, saying something like “There’s no way they’d be able to bring the structure down with a little truck bomb like that”.

Which is true because that truck bomb didn’t start much of a fire.

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**Author:** ![Magiver](https://avatars.discourse-cdn.com/v4/letter/m/4491bb/32.png) [@Magiver](https://boards.straightdope.com/u/Magiver)\
**Post date:** [November 17, 2012, 4:53am UTC](https://boards.straightdope.com/t/twin-towers-destruction-could-it-have-been-predicted/640957/27 "2012-11-17T04:53:18Z")

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> [@Valgard](#):
>
> Thanks, couldn’t recall it exactly.
> 
> The 1993 attempt to blow up the WTC took place when I was in civil engineering grad school. I remember one of my professors, a famous structural engineer, saying something like “There’s no way they’d be able to bring the structure down with a little truck bomb like that”.
> 
> IIRC, the plane strike analyses were done less with an actual attack in mind and more with an accident like the B25 hitting the ESB.

If I remember correctly the biggest plane at the time the building was designed was a 707.

One of the problems with the attack was that they managed to take out the single water manifold in both buildings that would have put the fires out. New buildings are now designed with multiple manifolds for sprinkler systems, wider stairwells, hardened stairwells, and better insulation for steel girders.

Sadly, the next attack will take a different vulnerability into account and we’ll react to that after the fact too.

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**Author:** ![Skywatcher](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/skywatcher/32/254_2.png) [@Skywatcher](https://boards.straightdope.com/u/Skywatcher)\
**Post date:** [November 20, 2012, 7:44pm UTC](https://boards.straightdope.com/t/twin-towers-destruction-could-it-have-been-predicted/640957/28 "2012-11-20T19:44:21Z")

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> [@Valgard](#):
>
> The 1993 attempt to blow up the WTC took place when I was in civil engineering grad school. I remember one of my professors, a famous structural engineer, saying something like “There’s no way they’d be able to bring the structure down with a little truck bomb like that”.

That truck bomb could have brought down at least one tower had it been parked directly against a vertical support.

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**Author:** ![edcnelson](https://avatars.discourse-cdn.com/v4/letter/e/c37758/32.png) [@edcnelson](https://boards.straightdope.com/u/edcnelson)\
**Post date:** [November 29, 2012, 6:03am UTC](https://boards.straightdope.com/t/twin-towers-destruction-could-it-have-been-predicted/640957/29 "2012-11-29T06:03:30Z")

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looked a lot like the way high rises are brought down using dynamite that is placed in very specific locations inside the building. Wouldn’t be surprised to find out our government played a part in the whole thing. What better way to get the people to believe they are under attack to justify starting a war. Maybe someday after all that were involved that can be held accountable are dead and gone we will know the real truth.

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**Author:** ![DWMarch](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dwmarch/32/1010_2.png) [@DWMarch](https://boards.straightdope.com/u/DWMarch)\
**Post date:** [November 29, 2012, 2:05pm UTC](https://boards.straightdope.com/t/twin-towers-destruction-could-it-have-been-predicted/640957/30 "2012-11-29T14:05:16Z")

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> [@edcnelson](#):
>
> looked a lot like the way high rises are brought down using dynamite that is placed in very specific locations inside the building. Wouldn’t be surprised to find out our government played a part in the whole thing. What better way to get the people to believe they are under attack to justify starting a war. Maybe someday after all that were involved that can be held accountable are dead and gone we will know the real truth.

And here I was all ready to praise this thread for the lack of conspiracy wingnuttery.

Think about this for a minute. If George W. Bush was indeed responsible for the events of 9/11 and this could be proven somehow, wouldn’t we of the SDMB not have done it by now? Bush and his cronies are generally hated on this board. Why would we let it go if we knew he was in on it?

Alternately we are all in on it (as you will see from the pile-on that follows your post) in which case your government possesses so much raw power it can do anything it wants and there is nothing you can even think of doing to stop it. The “truth” will not set you free.

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**Author:** ![Skywatcher](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/skywatcher/32/254_2.png) [@Skywatcher](https://boards.straightdope.com/u/Skywatcher)\
**Post date:** [November 29, 2012, 2:22pm UTC](https://boards.straightdope.com/t/twin-towers-destruction-could-it-have-been-predicted/640957/31 "2012-11-29T14:22:52Z")

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> [@edcnelson](#):
>
> looked a lot like the way high rises are brought down using dynamite that is placed in very specific locations inside the building.

Except for the fact that the collapses started at the top rather than at the bottom.

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**Author:** ![Ludovic](https://avatars.discourse-cdn.com/v4/letter/l/7ab992/32.png) [@Ludovic](https://boards.straightdope.com/u/Ludovic)\
**Post date:** [November 29, 2012, 2:24pm UTC](https://boards.straightdope.com/t/twin-towers-destruction-could-it-have-been-predicted/640957/32 "2012-11-29T14:24:46Z")

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Plus, how many high rises do you see fall that are not by controlled demolitions? They look like that because _that’s how big buildings fall_.

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