Time-optimal impact angle control for vertical plane engagements

As a part of trajectory modulation to increase terminal effectiveness, impact angle control is required in the terminal phase of tactical missile systems. Moreover, the missile systems are allowed to have only low altitude and minimum flight time to reduce the probability of detection by sensors of missile defense systems and thus to increase survivability. In this paper, a simple numerical solution for a time-optimal control law is suggested in the case of constrained missile maneuverability and impact angle for a first-order-lag autopilot. The numerical solution utilizes an analytic solution of a simplified problem with a zero-lag autopilot assumption to determine optimal switching instants. Performance of the proposed control law is tested by a simulation study.