This video shows an easy to build crash-proof 3D foam RC plane. The plane uses only 8 pieces of plastic laminated foam. Total cost for materials (not including electronics) was about $8. Here is list of other parts: BM2408-21 KV 1750outrunner brushless motor, GWS 10x4.7 propeller, Hitec receiver, 18 amp 7.4v brushless ESC, 7.4V 1300 mAh lipo battery, three 9g servos, 4 plastic clevis and 4 control horns, pushrods: two 14cm pushrods, one 13 cm, one 15cm. Note that many other motors, ESC, batteries, etc. will work.