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Re: Questions About the Events of September 11th (off topic)

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Mr. Park,

I don't fault you for starting a dialog and asking questions.  I must admit
that from the 1st day I volunteered to join the SEAoNY volunteer team I was
thinking about all the crackpots who would advance totally bogus theories to
support their preconceived notions, political bias, or TV-camera-searching
egos.

So, it came as no shock to me to read the contents of the link you provided
to the board.   I wouldn't doubt that a great many people who lack either
critical thinking skills or an understanding of scientific principles may be
duped by the type of 'information' on that website or other sources.  I do
think that we in the engineering community have an obligation to educate
people so they can detect obvious errors, oversights, opinion passing as
fact, etc.

We also must patiently await the detailed type of deliberative process that
science relies upon.  The Building Performance Study advanced a number of
theories with respect to structural responses to the events.  Those theories
are being tested by NIST and other parties to see if they stand up to
scrutiny and are supported by all the evidence collected.  Meanwhile, have
those interested in understanding the events of that day get a copy of the
Building Performance Study, FEMA 403, May 2002.  That preliminary work will
likely remain the best source of information until NIST publishes its
findings in perhaps two years or so.

I must also admit to having been surprised at some of the sources of equally
bad 'information'.  In a few cases, things have been said by engineers I had
respected that are completely wrong.  Other times, when engineers stated
something correctly, they were badly misquoted or quoted completely out of
context.   The recent 'MIT Study' reports come to mind.   I now see from a
post by Charlie Carter that I was not only one deluged with calls about that
one.  (It's always the bolt-guy's fault anyway, right?)

Even in the simple act of reporting on operations after September 11th, the
media have made numerous blunders when we thought they understood the
processes going on when we showed them or told them about them.  (It is so
bad that I have suggested to colleagues who intend to speak with press about
WTC-related work that they record the conversations themselves ---- as proof
as to what they actually did say.)

With respect to one of the questions you pose, and in the interest of
education and discussion:


> . . . the columns should
> be melt evenly otherwise some columns fail first then
> part of the building will tip over into other
> buildings.

The WTC Towers couldn't have tipped over.  It's physically impossible.
Although in my opinion it is likely the terrorists were not aware of this or
the 2nd plane would not have risked the high-speed U-turn it had to do to
strike Tower 2 from the South.  The rotation of the top portion of WTC 1 at
the initiation of its collapse likely depicts as much 'tipping' as one can
expect.  (Perhaps the modeling done at Weidlinger can be a tool to explain
this topic.)   Even though the top of WTC 1 'tipped' and did so at such a
great height, the debris field is not dramatically schewed in that
direction.

I think a great deal about the topics you have raised questions about are
best answered by a read of the FEMA 403 report.

Best regards,
David Sharp
TurnaSure LLC
NYC



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