Now that we have finished with the basic calculations, we have determined our best shot at a low cost, practical airframe was to support the balsa with glass and later kevlar composites. Our plan is to use 4 layers of 2oz glass for the fuselage. That should give us more than enough structure for 3g in a 20# aircraft.
We are trying to make a new version of the rail system for the engines. That will make it easier to package and ship. Our goal is to be under 80oz for the airframe and under ten pounds for the aircraft without instrumentation. Which is great, to get more than five pounds of usable payload.