Wind tunnel test and modeling analysis of cable-covers induced rolling aerodynamics on a tailless missile

In order to reduce structural weight, costs and improve system reliability, the rolling control system of advanced missile is always simplified or eliminated. At the same time, the surface of missiles is generally arranged with protrusions such as cable covers, hooks. These protrusions could produce small rolling aerodynamic moment under certain flow angles, which could induces missiles departing from predetermined trajectory, even leads to mission failure. Therefore, the rolling aerodynamic moment from protrusions should be measured and evaluated accurately before flight test. In this paper, the test technology of continuous rolling of gas bearing to measure small rolling moment is used to complete wind tunnel tests of a tailless missile. The slenderness ratio of this missile is nearly 9, and with cable covers installed on all three boost sections. Based on experiment data and aerodynamic modeling technology, a mathematical model of variation of rolling aerodynamic moment is established. Based on this mathematical model, parameter identification method is used to identify rolling aerodynamic moment coefficient induced by different cable covers from rolling angular velocity measured in different wind tunnel tests. The results indicate that the rolling aerodynamic moment induced by cable covers of secondary boost section, which are circumferential 180 ° symmetrically distributed, is most significant and ten times higher than others. Meanwhile, the maximum value appears at transonic tests. The rolling aerodynamic moment induced by cable covers of the first boost section, which are circumferential 90 °uniformly distributed, is relatively small, and its effect on motion of missile can be ignored.