
Mar 11, 2004, 01:05 AM  

OK, let's try again...
Look at the weights and wing areas of your other planes. Figure out the square inches, divide by 144 to get the number of square feet. Then figure out the ounce pers square foot. You should get some idea of how much weight a square foot will hold up. Heaveier weights per square foot of wing area will fly faster than lower weights. Find the one you like and pick that as your target loading. Figures for park flyers are perhaps 6 oz/sq foot for the sake of argument. Now weigh the motor, gear, batteries, and take a guess at the airframe weight. Add that all up. Using this weight, figure out how many square feet (or square inches) you will need to keep that wing loading. Once you have the area your plane needs you can divide that in half (for your biplane). Pick an aspect ratio (like 6:1 is common). Area = span X chord (and span = 6 X chord for 6:1 AR) therefore, Area = ( AR times 'X')('X'), or Area = X squared times AR X squared = Area / AR If each wings area is 100 sq inches, then X squared = 100 / 6, or X squared = ~16, and X = 4 Your wing would then be 4" chord, and 24" span... It's just algebra... 
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