[TowerTalk] Tower Mast Wind Loading

[Robert Kellow]

The problem statement might be incomplete.
The type of tower was not stated (self-supporting [and type of SS]; or
guyed. If guyed, is the top section guyed at the top?)
Depending, the top section may be overstressed by shear and moment forces. 
Bob, W5LT

-----Original Message-----
From: Ed Sawyer [mailto:sawyered at earthlink.net] 
Sent: Wednesday, July 06, 2016 7:00 AM
To: towertalk at contesting.com
Subject: Re: [TowerTalk] Tower Mast Wind Loading

I have a 22 ft .25in wall steel molly mast.  It is very strong.  

 

I think you are asking the wrong question.  With only 4 ft in the tower and
12 ft above, with the torque translated by this very strong based overwhelm
the top of the tower connections - thrust bearing and rotor connection.

 

The usual rule of thumb is to have 50% of the length in the tower.  I have
10 ft of the 22 ft mast in the tower and the top antenna is 9 ft above the
tower.  The last 3 ft are for a truss.

 

Ed