Friday, September 21, 2007

Re: FURTHER ON WTC

On Sep 21, 2007, at 11:09 AM, Gerard Madden, SE wrote:

> People can second guess the truss connections all they want, but
> the fact is they are gravity connections and performed fine up
> until they were asked to do something unintended.
>
> Can a sprinkler system be expected to put out a fire like that and
> save the building? No. Was the facade supposed to shred up the
> airplane and withstand blast pressures? No.
>
> Simple as that.
Not quite that simple, especially if the questions are posed to learn
something, rather than sharp-shoot the design. Sharp-shooting is bad
all around as are phrases like 'moral corruption,' because they don't
contribute anything worthwhile.

A worthwhile effort would begin by contrasting the 9/11 attacks with
the B-25 crash into the Empire State building in which the building
remained standing and the toll was 14 dead. The episodes differed
greatly in matters of fire safety, the nature of the aircraft and
building structure. I'd think that somewhere between those two
episodes there's a point where building design can be improved to
withstand accidents of the sort. There's no reason to believe that an
airplane couldn't hit another tall building, even by accident, and
it's worthwhile considering corrective measures. But just calling a
designer morally corrupt and blaming a lot of people without
presenting firm evidence is just whiney and demeaning.

Christopher Wright P.E. |"They couldn't hit an elephant at
chrisw@skypoint.com | this distance" (last words of Gen.
.......................................| John Sedgwick, Spotsylvania
1864)
http://www.skypoint.com/~chrisw/

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