Saving Weight
Here are some weight saving ideas:
Use a small AAAA Ni metal hydride battery (0.19 oz. per cell) total weight 0.76 ounces.
Use JR 368 digital servos @0.9 ounces each. total wt. 2.7 oz.
Use Hitech 555 receiver @ 0.3 oz. total.
Use spyder foam because it has less than half the weight of even the lightest contest balsa.
Use unidirectional carbon fiber because it has at least 7 times the strength to weight ratio of aircraft spruce.
Vacuum bag the wing and use the wing skin as the elevon hinge.
Use kevlar in laminating epoxy wing skins.
Mold the engine and pipe cowling of Kevlar cloth in laminating epoxy for the toughest, lightest and most vibration resistant structure.