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[TowerTalk] Rotating tower failures ?

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Subject: [TowerTalk] Rotating tower failures ?
From: "Jim Thomson" <jim.thom@telus.net>
Date: Mon, 9 Sep 2019 04:17:49 -0700
List-post: <mailto:towertalk@contesting.com>
<PiRod does not approve of rotating towers (the steel tower cork screws) -
<which is a significant problem. Rohn towers (pipe vertical legs) are worse.

<73
<Tim K3LR## Has a rotating tower ever  collapsed because of  the  
tower....corkscrewing,  or  been  permanently twisted ? The  guy  wires are not 
 attached to  the tower, but  to the  rings. The  tower isfree  to  corkscrew  
all it wants to.   It  would be  like  having a 100-200 foot long driveshaft on 
a car. I  only  heard of  one  case  where the  wind  was  trying to  rotate 
the  yagis..clockwise....  while the op  was  trying  torotate the tower  
counter  clockwise.   Base of tower rotated 20 degs CCW....meanwhile the top 
yagi had not  moved an inch ! Finally,  the  top  yagis caught up..and had  
rotated 20  degs.  ## What  does the  entire  array look like, when  in a 
80-100  mph  wind?   With  all  the  yagis  mounted to the  same tower face, 
youalready  have an  offset  load. With yagis mounted at their CG, and no  tq  
comp  sail  installed,  and  wind  broadside to  the  booms,you  will  end  up  
with an absurd amount  of  TQ  at  the  base of the  tower.  Jim   VE7RF 
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