Many years ago we had a bad ice storm here in the Carolinas and the local tv
towers were standing until the sun came out and melted the ice on one side
of the tower. Several of the tower which were around 2000 feet collapsed.
http://www.oldradio.com/archives/warstories/WRAL.htm
Mark N1UK
----- Original Message -----
From: "K0DAN" <k0dan@comcast.net>
To: "Dan Bookwalter" <N8DCJ@YAHOO.COM>; <TowerTalk@contesting.com>
Sent: Tuesday, 01 February, 2011 2:01 PM
Subject: Re: [TowerTalk] TX-472 and Ice
> Depends on a lot of variables. It's not just the ice, but wind loading
> upon
> the steel + ice + coax + rotor + whatever other forces are acting on the
> tower. And of course, did the installation meet mfgr specs (how are they
> rated for wind/ice loading), what's the soil like, are the tower footings
> intact, etc., etc. The answers to these questions are often educated
> guesses.
>
> About 7-8 years ago we had an amazing ice storm, I had over 1/2" radial
> ice
> on everything, and the storm hit before I could lower the tower (TriEx
> LM470). Once the ice was on we then got 30-40 MPH winds. It survived (so
> did
> the antennas!), but I was biting my nails the whole time. It took 3 days
> before the sun came out, and slowly it all melted and amazingly the
> antenna
> spring back to original shape.
>
> Since that nail-biter, I always try to play cautious and lower "my
> investment" when inclement weather is forecast.
>
> Last night, as the storm approached I went to lower the tower...there was
> already a thin layer of ice on everything. Started the motor and the fuse
> blew (usually indicates too big a mechanical load or water intrusion in
> the
> motor relay or starter caps). This summer I did major preventative
> maintenance, including replacing the motor caps/relay so I didn't think it
> was them. Replaced the fuse and motored the tower UP a little. Fuse didn't
> blow this time and then I was able to break a little of the ice free, then
> motor DOWN about 3-4 feet, then motor UP, then DOWN, etc. This eventually
> broke all the ice free (much of it fell on me) and I was able to get the
> whole structure down. Usually a full retraction takes about 6 minutes,
> last
> night it took 20 minutes what with all the UP/DOWN. It's amazing how
> strong
> a thin layer of ice is on all the cables and steel surfaces!
>
> I was lucky...so were you!!!
>
> Looking out the window now it looks like Siberia. I don't expect to do
> much
> operating the next few days!
>
> 73
>
> Dan
> K0DAN
> ----- Original Message -----
> From: "Dan Bookwalter" <n8dcj@yahoo.com>
> To: <TowerTalk@contesting.com>
> Sent: Tuesday, February 01, 2011 7:45 AM
> Subject: [TowerTalk] TX-472 and Ice
>
>
>>I went out this morning to crank the tower down for the pending Ice storm
>>,
>>the
>> problem is that the top section is stuck , i got lucky i was cranking
>> away
>> and
>> looked up and saw about 10-12 feet of cable hanging out the side of the
>> tower ,
>> which scared me to death , i quickly cranked it back up before the top
>> section
>> broke loose , my question is with nothing on top of the tower except a
>> wire
>> antenna , will the tower handle up to a 1/2 inch of ice when it is
>> extended to
>> about 60-65 feet ? i don't think we are supposed to get any major wind
>> just
>> sleet and ice.
>>
>> thoughts.....
>>
>> Dan N8DCJ
>>
>>
>>
>>
>> _______________________________________________
>>
>>
>>
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