Calculation of generalized aerodynamic forces, GAFs, for aeroelasticity equations with less effort than that required in the ordinal method is studied. The basic idea of our method is that any modal vectors are reconstructed with basic modal vectors by applying linear combination of them. If we prepare the GAFs for the basic modal vectors, we can easily acquire any GAFs for the structure having its modal vectors expressed by the basic modal vectors, unless the planform of the structure remains the same. In the study, our method was applied to each of rectangular and tapered wings. At the beginning of our study, the basic modal vectors were chosen with the structural modal vectors acquired from a structural model considered as the original structure to be varied with its structural characteristics. Unfortunately, only with these basic modal vectors, the accuracy of our method didn’t show high accuracy. By applying artificial structural modal vectors adding to the above mentioned basic modal vectors, both accuracies of modal vector reconstruction and GAF calculation get increased. At the conference, the outline of our method will be explained, and the results applied to the rectangular and tapered wings will be presented.