ORIGINAL: DBCherry
True, many giant scale planes use foam for wings, and some use foam for major portions of the fuselage too (not the aerobatic stuff).
But for that matter, most Pattern type airplanes use foam wings too, so the materials are still fairly standard.
Dennis-
I found out they used foam because I have someone at my field that I asked why you didn't see the ribs coming out of the wing....so I asked the guy and he said that the stuff that they do, they use the foam, since that is "a little stonger than the balsa for the aerobatics they do"....and they make the covering look so good where you don't see any ribs or inperfections...because if they use the foam....they usually sheet the wing and that will give you the nice flat smooth finish that most people see when they see a giant scale plane......