[TowerTalk] US Tower MA 550 Windloading - 90MPH?

[Robert Chudek - KØRC]

Hello Al,

With this new engineering obstacle in your path, you need to start looking at heavy duty towers, as suggested in other parts of this thread. Having to provide a design with 1/2" of radial ice loading to the city puts your installation into a commercial grade tower. Not only does the ice add surface area, it adds incredible weight to a structure as well.

For reference, the Heights Tower Company lists a standard 32 foot tower capable of supporting 8 sq ft of antenna in 100 mph winds with 1/2" radial ice. You will find it listed near the bottom of this page (scroll way down the page, right above the picture of the 92 foot tower rated for 150 mph winds that was installed in south Florida):  http://heightstowers.com/stacked_tapered_towers.htm

Under that photo is this statement: "Heights Towers can provide engineering calculations and diagrams signed by a Professional Engineer licensed in your state for $350 on standard tower configurations." Few, if any, amateur tower manufacturers provide this type of engineering help.

If I remember correct, you have HOA approval for a 70 foot tower. I would call Drake at Heights Tower and talk to him about your new requirements and which Heights products could satisfy the specs. He says they can provide a "PE stamp" to satisfy the city even on custom configurations. Heights also manufacturers crankup towers, although they are lattice, not tubular.

Also, don't confuse the Heights design with the popular Universal towers. There is no comparison in capacity or workmanship. I have installed and worked on both types. The Heights sections join together with couplers. The legs are not nested. On the larger sections, they join together with flanges, like the Pyrod commercial products. Gary Meyer, KCØSB, had an 88' self supporting Heights when he lived in Forest Lake.

The only "good" I see out of this ordeal is you can send the neighbors to the "Commissioner" if any of them complain about the esthetics.

73 de Bob - KØRC in MN



Message: 8
Date: Tue, 12 Sep 2006 16:12:06 EDT
From: Aldewey at aol.com
Subject: Re: [TowerTalk] US Tower MA 550 Windloading - 90MPH?
To: jimlux at earthlink.net, w7ce at curtiss.net, towertalk at contesting.com
Message-ID: <2fb.5b1d3d80.32386e96 at aol.com>
Content-Type: text/plain; charset="US-ASCII"

In a message dated 9/12/2006 1:00:12 PM Central Standard Time, 
jimlux at earthlink.net writes:

I think you've hit the nail on the head.  Local authorities are 
imposing "commercial grade" kinds of requirements for the permitting 
(if only because it's easy, not to mention, it's legally defensible 
in a PRB-1 environment), so you need "commercial grade" stuff. Tall 
light posts and free standing cell towers have no problems, but are pricey.

This, to my mind, is a far more insidious trend than the HOA CCR 
problem.  Pretty soon, the only hams who will be able to experiment 
with towers will be the ones who own acres of farm land in a lightly 
regulated jurisdiction.

Jim, W6RMK 

Jim and all;

I think you are right.  I thought the hard part would be getting an exemption 
form our CCRs.  I was able to do that with not a big problem.  But I spent 30 
minutes with the City Building Commission here in Plymouth, Minnesota and he 
insisted on 90 MPH Wind Loading, 1/2 radial ice, with the antenna fully 
extended (i.e. not nested).  He would not move off this position no matter what I 
said.  I tried all kind of arguments like precedent installations, aesthetics, 
etc. but he would not have any of it.

Not sure what my next move is.

Al, K0AD