Mark I plan to follow your method for skinning the outer wing panels - i.e. to have a true composite sandwich between the spars and fully bonded to both spars. In my case, the same deal for the D box (as you did with your centre section LE).
I was surprised to note that you have no intermediate ribs between the spars in the outer section. You have gone to great lengths to ensure a sound bond between the spars and both inner and outer layer of the wing skins, in particular the top skin - you are obviously comfortable that this arrangement will transfer all the flight loads for and aft to the respective spars without the need for any columns other than the ribs at the root and tip. The three 2" poly U ribs (as per the plans) will have a significant contribution in their compressive capacity (when some clown sits on the wing) but you have addressed that via a pretty robust sandwich skin. Question in my mind is how much these 3 ribs contribute in their tensile capacity. With some 60 sq" each (2 x 30) there is a total of 180 sq inches additional support area (compr and tensl) from these 3 ribs. I have not thought this through yet, but I will probably face the (3) ribs with a glass skin that develops into a flange and look for a good bond with the skin - at least on the top. 8 ounce cloth with resin - total 1lb per square meter - the weight penalty will be negligible - maybe 2lbs. I expect you have thought about this - hopefully you have a moment to comment. Steve J
