Thread: PRB-1 and CCNR's
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Old March 25th 07, 03:48 AM posted to rec.radio.amateur.moderated
Phil Kane Phil Kane is offline
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First recorded activity by RadioBanter: Jan 2007
Posts: 300
Default PRB-1 and CC&R's
On Wed, 21 Mar 2007 21:16:00 EDT, wrote:

Depends on the size of the lot. On a lot that's , say, 100
feet wide, you can't put up a tower more than 50 feet high
and have its "fall circle" not go over the property line.

As we all (should) know, towers rarely, if ever, fail in "stick fall"
mode where the fall zone radius is equal to the tower height. The
usual fall mode is a buckling collapse along the length of the tower
resulting in a fall radius of about 10-15% of the tower height.

There was a study made of commercial tower failures several decades
ago that showed this, and I've seen this first hand in some of the
broadcast and comm towers affected by the 1989 Loma Prieta earthquake
in the San Francisco area.

Whether the local building official is sharp enough to know this is an
exercise left to the applicant....!
--

73 de K2ASP - Phil Kane

From a Clearing in the Silicon Forest
Beaverton (Washington County) Oregon

e-mail: k2asp [at] arrl [dot] net

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