From: "Marvin Kaye" <marv@lancaironline.net>
Subject: Re: [LML] Re: Gross Weight & Balance of IV-P Tacoma Narrows
 Bridge
To: lml
Date: Mon, 15 Sep 2003 11:55:22 -0400
Message-ID: <web-2580091@logan.com>
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Posted for "Joseph Trepicone" <trepicone@earthlink.net>:

(marv if this is not an appropriate post feel free to disregard it)
[ nuked your mpeg file, but here is a link to its source
and another links found from google when I was searching 
for your movie's source.
http://www.civeng.carleton.ca/Exhibits/Tacoma_Narrows/
http://www.ketchum.org/bridgecollapse.html
http://www.pbs.org/wgbh/buildingbig/wonder/structure/tacoma_narrows.html
   -Rob ]

Brent's example of the Tacoma Narrows Bridge is excellent and I thank
him for it.  For what it's worth I could not agree with the point of his
post more.  However I'm not sure it is really a completely appropriate
example in the case of overloading an aircraft.  It is true that the
bridge suffered from the engineer's (Leon Moisseiff) lack of
consideration of the aerodynamic forces on the bridge design.  The
violent oscillation which led to it's demise had little to do with
additional live load but rather was due to wind-induced vibrations.
 From this tragedy much was learned about the proportions of bridge
design - length, width, and depth.  The fact is the bridge would have
failed with no live load at all.  Thanks Brent for this eye opening
example.  I'm including a small video clip for those interested.

Joe Trepicone IVPT