This paper presents an approach for optimizing practical commercial-scale aircraft wings using sandwich composites in a preliminary design stage. The approach uses lamination parameters as design variables in a continuous optimization step. Structural constraints for classic composite laminate design such as material failure and buckling, and for sandwich design such as crimping, wrinkling, dimpling, and core shear failure are accounted for using industrial-standard and empirical methods driven by finite element analyses. As an application case, optimization studies are performed at a skin panel level on the open-source Common Research Model wing. Optimization trends show areas of the wingbox where sandwich composites offer superior structu...