For a few years, I've offered this little set of RC parts, free, from my 3D Catalog page. (Scroll down to the bottom, at http://www.nextcraft.com/3d_catalog_000.html
There you'll find a free download of these parts, in DXF format:
Fixed landing gear, with wheel pants, generic 2-stroke engine, generic 4-stroke engine with tuned exhaust, fuel system with tubing, servos, plug-in type wing attachment hardware, 2-blade prop and spinner, Klett-style tailwheel assembly, etc.. This might help some of you visualize your models quickly, if you don't want to make those parts.