The aeroelastic divergence characteristics of unguided slender rocket-vehicles have been performed from the general equations of motion. The elastic deformation of a rocket-vehicle subject to aerodynamic and inertial loadings is determined using the finite element method on the assumption that the center of deformation is fixed. The effect of joint rotations on the elastic deformation is included in this analysis. The divergence deformation pattern is assumed to be the first bending vibration mode. Aerodynamic forces are obtained for the selected four types of rocket-vehicles from the available references. The equations of motion for the lift and pitching moment are derived and Laplace domain stability analysis is carried out, which gives divergence dynamic pressure. The present method gives quite accurate results on the divergence dynamic pressure of slender rocket-vehicles.
