Thank you all for the information. I knew I could find good"stuff" out
there.
The wind generator (not an antenna) I was planning has limited
information available as to loads. ie. No Flat Plate or FPE numbers.
The only statement is that the tower must take a 200 pound lateral
thrust and not deflect more than six inches with winds of 200 mph. The
Trylon T-200 tower specs. for my maximum wind speed area (from the
chart at their web site),
shows that the T-200 will take a 42 pound lateral thrust at winds of 85
mph.
If 120 mph winds cause the wind generator to exert 200 pounds of
lateral thrust, what speed of the wind will yield the 42 pound maximum
lateral thrust that the tower will hold? Please show your work.

fcrumpler,
Figured as a simple ratio, about 25-30 mph. No idea if
that's accurate...
'Doc

Dear "fcrumpler" no call, no location:

Theoretically, the force produced by moving air impacting on a flat
plate is proportionally to the square of the air's velocity. However, in
the real world where one should appropriately deal with wind gusts and
variability of materials, things are not so simple. Safety factors should
be used. Accommodation for the significant vibration to be caused by your
proposed "wind generator" must be made.

Numbers supplied by some vendors involve no safety factors.

You need to retain a Professional Engineer licensed in your state or
province who is experienced with vertical wind structures. This is
certainly the case if the proposed structure is able to damage other
property or endanger living things.

It is not safe for you to scale the numbers that you have. Too little
information. Too much risk.
Mac N8TT
--
J. Mc Laughlin; Michigan U.S.A.
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