http://en.wikipedia.org/wiki/Barkley...nd_development

I'm not sure I understand correctly the description of the wing
structure. I suppose that there are "spars" with an X cross section
that run spanwise through the wing and are attached to the skin at all
four ends. A cut through the wing would show lots of large hexagons
(between Xes) and small triangles (inside Xes). Does anyone have more
info on this?

Oliver