N4KG responses inserted below.
On Sun, 30 Dec 2001 Dick Flanagan <dick@libelle.com> writes:
>
> At 11:47 PM -0500 12/30/01, "Stephanie WX3K" <wx3k@ptd.net> wrote:
> >
> > Is there any thoughts on what direction a large HF beam should be
> pointed during a very windy day......Winds in excess of 30 MPH ???
> >
> > Directly into the wind ?
>
> It depends. :)
>
> What are you worried about?
>
> Are you worried about pushing over your tower? Calculate the
> position of =least= wind loading. For a large multi-element yagi,
> probably perpendicular to the wind.
Generally, there is less projected area perpendicular
to the boom than perpendicular to the elements. N4KG
>
> Are you worried about your rotor/mast slipping/weathervaning?
> Calculate the position of most =balanced= wind load, probably
> directly into the wind.
Since most antennas are mounted on the SIDE of the
mast, this offset represents considerable torque on
the mast / rotor when the elements are perpendicular
to the wind. If the boom is symmetrical to the mast,
the least torque may occur with the boom perpendicular
to the wind. N4KG
>
> Are you worried about bending/breaking antenna elements?
> Put those element into the wind.
>
> Like I said, it depends.
>
> I think I have pretty average concerns where I worry more about my
> rotor/mast slipping than I do about mechanical failures (either the
> tower or antennas), so I aim my antennas into the wind. Your milage
> (and concerns) may vary.
>
> 73, Dick
> --
> Dick Flanagan W6OLD CFII Minden, Nevada
> Visit http://www.cvrc.net/
>
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