Objectives  In the structural design of composite wing-in-ground (WIG) craft, there is no standard way to evaluate the strength and stability of the structure. In this paper, the calculation methods for the structural strength and stability of the composite sandwich main float and wing of composite WIG craft are studied.

  Methods  The theoretical methods for evaluating the structural design load of the main float and wing structure along with the corresponding strength criteria for sandwich panel are particularly discussed, as well as methods and criteria for the general and local stability of the sandwich panel. The overall longitudinal bending strength of the main float, structural strength of the composite sandwich wing, and their general and local stability are predicted and analyzed using the proposed method.

  Results  The results show that the proposed method can be used for the strength and stability analysis of the main float and wing of composite WIG craft, and the composite WIG design scheme in the calculation example meets the structural strength and stability requirements, which is then verified by a real ship test.

  Conclusions  This method can provide references for the design and structural analysis of composite WIG craft.