Structural Weight Comparison of a Joined Wing and a Conventional Wing

A structural weight comparison was made between a new concept wing design, called a Joined Wing, and a reference conventional wing-plus-horizontal tail (Boeing 727). The joined-wing analysis includes two cases that differ only in minimum gage skin thickness. The comparison was accomplished by constructing finite-element computer models of each wing configuration, analyzing each for optimum skin thickness, then determining the structural weight of each wing. The optimizations were based on a fully stressed design concept using a Von Mises criterion for maximum allowable stress. The joined wing was found to be lighter by 12-22%.