You've just finished your latest creation and now you're at the field showing it off. As you talk to your interested flying buddies while you try getting up the nerve for the maiden flight, there are many questions from everyone around... How much does it weigh? What engine are you using? What size prop? And of course... what's the wing area?

Well, if you built it from a kit or from plans, the wing area was there printed in black and white, so you recite it from memory. If you designed it or changed some existing design, you'll have to calculate the new area. Calculating wing area is not as difficult as some people think. Most wings are a series of rectangles and triangles.

These areas are fairly simple to find, for example, the area of a rectangle is simply its length times it width, (Area = L x W). The area of a triangle is one half the base times its height, (Area = 1/2 B x H).

If you should have a wing that is straight on either the leading or trailing edge and tapered on the opposite edge, simply break it down into a series of triangles and rectangles. This calculation process is very simple and shouldn't present any problems for any modeler.

But what do you do for finding the area of elliptical and semi-elliptical wings? If you should be presented with this problem, there is a relatively painless method of finding the answer. If you were to use a true ellipse as in figure 1, a very close approximation of its area would be as follows:

Area = (pi) x (L x W) x 1/4 where (pi) = 3.14.
L = the length at the major axis and W = the length at the minor axis.

However, most aircraft do not use true ellipses for wing shape. You'll usually see a modified form of an ellipse. Have no fear, it's not as difficult as it seems. You simply break up this shape into various geometric shapes that are easy to deal with.

See Figure 2. As you can see, you'll have six different areas to calculate. These areas are as follows:

	Area I = 2/3 (A-F) x H 
	Area II = 1/2 (B-F) x (A-B) 
	Area III = (B-C) x (B-F) 
	Area IV = 1/2 (E-C) x (C-D) 
	Area V = 2/3 (E-D) x 1 
	Area Vl = 1/2 (r x (S-)F-E) plus (E-F) x J 

After all the numbers are in, simply add them up and multiply by 2 for the total area. Now if you should have a wing that uses a straight or tapered leading or trailing edge there will be a few less areas for you to calculate. Although the above described method is not exact, it is a very close approximation and will be quite sufficient for your uses.

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