The Boeing-McDonnel-Douglas F/A-18E fighter jet has a radically opportunistic structure in terms of both engineering and manufacture. It is a hybrid of semi-monocoque construction out of steel, titanium, and aluminum- used for the fuselage and wings, and carbon-fiber construction- used for the ailerons, rear fins, and other infill pieces. Rather than using a universal structural system, this jet is based on a radical optimization of structural zones using variable depth, thickness, grid size, and material properties. Its manufacture, involving a network of every major aerospace company in the U.S., reflects this radical variability.