Abstract: The rigid/elastic coupling dynamic equations were utilized based on quasi-steady hypotheses to obtain the nonlinear static aeroelastic equations in this paper. Combined with nonplanar vortex lattice methods and nonlinear FEM, iterative methods were adopted to simulate the nonlinear static aeroelastic response. A wind tunnel test was implemented to reveal the nonlinear trends of loads and structural deformations. The linear static aeroelastic analysis cannot consider the structural geometry and non-planar effect when the deformation is large. Therefore, there are some differences compared with wind tunnel test and nonlinear analysis. For very flexible aircraft, the nonlinear static aeroelastic analysis is significant for accurate aerodynamic evaluation.