[Top] [All Lists]

[TowerTalk] Wind and Paranoid vs. Overkill

To: <>
Subject: [TowerTalk] Wind and Paranoid vs. Overkill
From: (Robert Shohet)
Date: Tue, 11 Sep 2001 08:17:39 -0400
Hi Guys,

Based on my experiences, I would tell anyone and everyone to make your
installations MUCH bigger and stronger than what your local wind zone
suggests.  Likewise, reinforce your antennas and double nut and double clamp

Here in extreme SW Connecticut, I believe the wind zone suggests something
like 70 mph.  (I don't recall).

In the 7 years that I lived here, we have had at least 10 blizzards with
winds well in excess of that, 5 or 6 Northeaster's with wind gusts easily to
80/90 mph, two T-storms last year WELL BEYOND 100 mph (one was 120+!), one
small tornado 2 miles away (100+ mph winds), and two T-storms this year
again with winds 100+ (microbursts).  All-in-all, I believe we have had AT
LEAST 50 storms well beyond 70 mph, 30+ beyond 80 mph, 20 in excess of 90
mph and at least 5 > 100mph (with no hurricanes).

You would not expect these kinds of winds here in Connecticut for an area
not usually hit with Tornados, although we do get lots of vicious T-storms.
My point is that zones be damned, localized WX phenomena and local terrain
determine what kind of storms can hit and what you will need to do to stand
up to them.  More often than not, you will have no clue as to what it really
possible until AFTER it hits, and then it is too late.

In my case, due to building towers on ledge and digging out huge boulders
with a backhoe plus my own skepticism, the concrete tower bases and anchor
holes were made much bigger than rohn spec and with much more concrete than
rohn suggests.  I am certain that my towers would not be up otherwise.  Same
with the antennas.  The cost and time effort of "overdoing" is a fraction of
the initial project cost and time involved.  It is a no-brainer that will
make your health much safer and your enjoyment of the hobby much more

Fortunately we have not had any hurricanes since I have been living here, so
I can't tell you how everything will stand up to many hours of 100+ mph
winds, but I do know, that there would be no chance without all the extra
work that was done when I installed everything, including 2 - 3 cu yds. of
concrete in each anchor hole and 5 cu yds of concrete in one of the tower


Bob KQ2M

> > If my feeble memory serves me, I'm in an 80 Mph zone. In the past year
> > alone, we have had two occasions of officially recorded straight-line
> blasts
> > of over 90 mph (recorded at the airport about 4 miles east of me). The
> last
> > one took down a dozen or so very large trees around my place, and ripped
> out
> > about 100 feet of split rail fence. So charts be damned, I built my
> recently
> > erected guyed R45 to Rohn's 110 mph specs. Total added cost to get from
> > to 110, as far as I can figure, is about $75 worth of extra concrete,
> > extra sweat in digging larger anchor holes, and an added $100 or so more
> to
> > buy 4130N mast material vice something a little more bendable.  I'd go
> > the overkill on the wind speed rating, and give up a little tower height
> to
> > do it if necessary. You'll sleep better at night, I promise.
> > 73, Jerry W5KP

List Sponsored by AN Wireless:  AN Wireless handles Rohn tower systems,
Trylon Titan towers, coax, hardline and more. Also check out our self
supporting towers up to 100 feet for under $1500!!

FAQ on WWW:     
Administrative requests:

<Prev in Thread] Current Thread [Next in Thread>