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 ```Gentlemen: Can Someone verify my wind loading calculations for my quad? I think I must be doing something wrong. 3 elements on 15M and 20M with 4 elements on 10M. Boom is 3 inch at 18 ft long. Calculations: Spreaders are 1.5 inches Dia X 312 inches long (26 ft;tip to tip)= 468 square inches each 468 X 2 for each large element = 936 square inches. 936 x 3 elements is 2808 square inches. 10 meter dedicated element spreader is .75 dia X 144 (12 ft;tip to tip) = 108 inches square 108 X 2 for the total 10M element is 216 square inches. 2808 + 216 for all spreaders is 3024 square inches. Boom: 3 inches dia X 216 (18 feet long) = Boom 648 square inces. Mast 2 inches X 96 (8 fee)t = Mast 192 square inches Mast Plate 6 X 10 = Plate 60 square inches. Wire = .1" Dia X 5904 (492 feet (3band) = Wire 590 square inches. Adding all this up = 3024 +648 + 192 + 60 + 590 = 4514 square inches! Since a square foot is 144 square inces (12 X 12), I divided 4514 by 144 to get a total of 31 square feet. If I mutiply by .66 for the round surfaces, I now get 20.7 square feet. Does this seem heavy? The quad weighs about 75 lbs and is on top of a 51 foot tri-ex crank-up tower. What about the rotor? about 1 square foot? Cables? I would have "thrown a number of" 10 feet st the beast, but now that seems crazy also. Most quad manufacturers list this type of arrangemaent at 9 to 10 square feet. Who's right? Any Ideas??? I have been keeping the tower cranked down at 40 feet during 25 MPH+ wind. When I get nervous, I drop it to 30 feet. AT 35 feet and 45MPH a few weeks ago, I had no problems (except HAM-4 brake slipping), but I'm not sure if it would have survived if at full height! Thanks George AB2KC ```