Hi George, what you did wrong is calculate the total area of the
antenna. The wind pressure is maximum when it is perpendicular to a
surface and minimum when the wind is in line with a surface or wire. You
have to do two calculations, one with the wind in line with the boom and
figure out which surfaces are perpendicular to the wind and add up the
surface area and one set of calculations with the wind perpendicular to
the boom and do the same. The higher of the two numbers is the max wind
load on the tower. One thigh you have to remember is that most crank up
towers are only rated for max wind load at 50 mph and when the wind
speed starts climbing the tower becomes very difficult to pull down
especially if it does not have a pull down cable. The is why you see
most crank ups sitting the the collapsed position and when you want to
use it you have to crank it up. A real pain but the nature of the beast.
73 Steve VE3TU
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