In a message dated 8/27/02 2:37:44 PM Pacific Daylight Time, k5uj@hotmail.com
writes:
> The local newspaper's wx section yesterday had a writeup about Hurricane
> Andrew since this was the 10th anniv. of its landfall. It stated that it
> sustained winds of 165 mph with gusts of over 175 mph., when it hit Fla.
> just south of Miami. As a ham I naturally thought first of the Miami area
> commercial towers (was pretty sure ham antennas all blew down) and
wondered
> if they were built down there to make it through something like that?
Are
> commercial towers for tv and radio etc. built for something like that down
> there or does everyone keep their fingers crossed and stay out of the way
> downwind of the towers and get the heck out of town? I can't imagine
> building a tall tower that could survive an extended blast of cat. 5
> hurricane. Just wondering.
Winds of that force are unbelievable. Sometimes the towers stay up but
the antennas blow off and become lethal weapons (like just about anything
else flying thru the air at the time).
I just talked to a guy in Broward County and he said that the county
building code there now calls for 140 MPH windspeed compliance. It's not
difficult to design towers to meet that kind of wind pressure but you can bet
that the towers will be expensive.
You might be able to get a small big Trylon to meet that criteria and
probably the AN Towers too. The problem is that the wind pressure isn't
linear so pressures go up real fast.
Cheers,
Steve K7LXC
TOWER TECH
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