Abstract:A predictive guidance method based on linear gravity difference model is proposed for the midcourse guidance of an airborne kinetic energy interceptor, which has the characteristics of negligible aerodynamic force and the inability to accurately calculate gravity deviation in real time. The gravity deviation between the interceptor and the target is approximated by a linear model. The thrust vector of the interceptor is adjusted and the gravity deviation is eliminated. On this basis, the delay ignition strategy is adopted to make the interceptor boost stage of interceptor better correct the deviation between the prediction model and the actual situation. The simulation results show that the miss distance of the whole midcourse guidance can be limited to a smaller value, thus providing a good initial condition for the terminal guidance.