Structural design of high aspect ratio composite material wing

Based on the structural characteristics of high aspect ratio wing, the sandwich, multi-spar structure and an innovative mixed structure are designed and compared. The experimental investigation is made for the compressive strengths after low speed impact of stitched and non-stitched laminates. The compressive test is conducted for three forms of honeycomb sandwich laminates. The experimental result indicates that stitching can enhance the compressive strength after low speed impact and the buckling load of the composite laminate. The finite element analysis method is adopted to compare the mixed structure with the other two structures. The calculation implies that the innovative mixed structure possesses obvious effect of decreasing weight, and that it can meet the requirement of the ratio of the torsional stiffness to bending stiffness.