Coning motion and restrain of large fineness ratio unguided spinning rocket stabilized with tail fin

Through analysis the process of coning motion of large fineness ratio unguided spinning rocket stabilized with tail fin, indicated that the induced out-of-plane force and out-of plane moment of spinning is the reason of coning motion. The out-of-plane force and out-of-plane moment is mostly the Magnus force and Magnus moment at small angles of attack. The wind tunnel test were conducted to study the spinning characteristics of different rocket configurations with positive-fixed wrap-around fin, negative-fixed wrap-around fin and flat fin respectively. From the test results, we find that the usually used positive-fixed and positive-spin wrap-around fin would promote the coning motion of the rocket, but the negative-fixed and negative-spin wrap-around fin could decrease the coning motion of the rocket. So it is an effective measure to restrain the coning motion of large fineness ratio unguided spinning rocket stabilized with tail fin that adopting negative-fixed and negative-spin wrap-around fin.