I own a set of Dragon plans and construction manual and there are a couple of things that I wonder about. The first is this, except for the tailboom is there really a point to the carbon roving that is incorporated into the airframe ostensibly for structural reinforcement?
The roving can not possibly develop anywhere near its theoretical strength, mainly because it's impossible to keep all of the fibers straight and under consistent tension. Would not omitting all of the roving and making the sparcaps of solid or laminated Spruce result in a structure that is just as strong at very close to the same weight? The carbon roving in the flaperon ribs and trailing edge seems a bit gimmicky also. The flaperons already seem sufficiently robust in construction without the carbon. Lastly is the control parts that made of carbon like the torque tube, etc. Is this really needed? Why not aluminum? The ULF-1 uses no carbon, is it weaker than the Dragon? The Dragon's design seems quite normal for a wooden sailplane of its weight except for the roving. Any thoughts?
The roving can not possibly develop anywhere near its theoretical strength, mainly because it's impossible to keep all of the fibers straight and under consistent tension. Would not omitting all of the roving and making the sparcaps of solid or laminated Spruce result in a structure that is just as strong at very close to the same weight? The carbon roving in the flaperon ribs and trailing edge seems a bit gimmicky also. The flaperons already seem sufficiently robust in construction without the carbon. Lastly is the control parts that made of carbon like the torque tube, etc. Is this really needed? Why not aluminum? The ULF-1 uses no carbon, is it weaker than the Dragon? The Dragon's design seems quite normal for a wooden sailplane of its weight except for the roving. Any thoughts?
