Jim,
In hurricane winds, Andrew or not, a lowered and secured tower has to be
less of a threat to damage than one extended to full height. The wind load
is reduced, torque factors reduced, lever factor reduced, and there's far
less for it to damage falling from 10 foot eave height than from 60 ft
extended. If it fell from that height my neighbors homes would be at risk!
At the tilted over eave height level my entire tower presents a much smaller
wind load than a 60 foot long by 10 foot high mobile home and I'd venture to
say that excepting the mobile homes frame, there's a lot more strength in
the triangular structure of my tower than anywhere within the walls of those
mobile homes that wound up adorning the avocado trees.
Regarding the safety of a crank up tilt-over -- how can you substantiate
your opinion that a crankup/tiltover is LESS safe as far as servicing ? I
don't have to deal with potential for collapse because it's NEVER climbed
while extended, in fact -- it's never climbed! Why climb? That's what the
point of my argument was --- the crankup tiltover can be lowered to ground
level for any servicing. I replace any coax, any tower cabling, and
adjustments, any routine maintainance from the safety of ground level. You
want to know what the greatest danger from my crankup tiltover is ?? Bird
Droppings! I'd go back and reread my original post again with careful
attention to the adjectives -- "tremendously reduces" and "much safer", I'm
not claiming a panacea here, just common sense. Working at ground level is
safer than climbing aloft and a retracted, tilted over and secured tower is
not going to be the same risk as a fully extended tower guyed or not, in big
winds. How hard is that?
Bill
----- Original Message -----
From: "Jim White, K4OJ" <k4oj@tampabay.rr.com>
To: "Bill Otten" <res0958z@verizon.net>; <towertalk@contesting.com>
Sent: Friday, March 15, 2002 1:27 am
Subject: Re: [Towertalk] CRANK UP TOWERS - Not a panacea
> I think your fooling yourself...
>
> Having seen what Andrew did - NOTHING - no matter how low it is is any
less
> likely to become airborne!
>
> I saw the sides of mobile homes wrapped around avocado trees....they were
> low to the ground!
>
> If a hurricane is going to come it is going to come and it is going to
level
> anything it wants to, period.
>
> I feel that you are simply kidding yourself thinking that a lowered
antenna
> is safer. It is far less safer as far as servicing - it is far less safer
> as far as potential for collapse...
>
> A properly installed fixed tower is like a building - at the top of our
135
> footer (Rohn 55) it is rock solid - as if you are at the ground level. I
> swear you could park a car on it...I suspect the fears of tall fixed
towers
> are those of guys who prefer not to climb and not the feelings of those
who
> it, especially those who do it for a living...lets hear from some of the
> tower pros logged onto this reflector...
>
> If it gives you a warm fuzzy to think lowering your antenna is better -
> great - but I would be interested to hear the professional response on
this
> as far as which type of tower they would rather work on....I think it will
> be the fixed one where there is less to go wrong.
>
> 73,
>
> Jim, K4OJ
>
> ----- Original Message -----
> From: "Bill Otten" <res0958z@verizon.net>
> To: <towertalk@contesting.com>
> Sent: Thursday, March 14, 2002 11:56 AM
> Subject: Re: [Towertalk] CRANK UP TOWERS
>
>
> > Yes! One of the benefits to having the crank-up /tilt-over tower IS the
> > capability of removing it from harm's way during severe weather. Being a
> > Florida resident (besides being a resident in the Lightning capital of
the
> > USA -- we just lost the world title to Rwanda!) we occasionally get a
> major
> > storm. Anyone who thought their tower might survive -- guyed or
otherwise
> > during Hurricane Andrew got his hurricane party started a bit too early.
> > Common sense would suggest that if homes, railcars, yachts, buildings,
> > trees, and just about everything else was in danger -- towers might be
> > also?? Having the crank down/tiltover tower tremendously reduces the
risk
> > to calamity too -- again, simple common sense. Tilted over, my tower
sits
> > lower than the eave of my home and once tilted is supported by the base
> > fixture and the support fixture some 25 feet away. Undeniably, it's MUCH
> > safer that way in severe winds than extended to it's full 60' height
with
> 12
> > sq. ft. of antenna!
> >
> > Bill KC9CS
> >
> > ----- Original Message -----
> > From: "Paul Christensen" <w9ac@arrl.net>
> > To: <towertalk@contesting.com>
> > Sent: Thursday, March 14, 2002 12:30 pm
> > Subject: Re: [Towertalk] CRANK UP TOWERS
> >
> >
> > > > I got to disagree with you on this one K4RV...
> > > >
> > > > No way is having a crank down and or tiltover better - I would go
with
> > the
> > > > guyed tower over and over again - ESPECIALLY AFTER SEEING WHAT
ANDREW
> > DID!
> > >
> > > Isn't a major point in owning a crank-up tower that the operator
> > completely or at least partially nests the tower when not actively
> > > operating?
> > >
> > > -Paul, W9AC
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