Design and Development of a Morphing-FinHybridRocket-Powered Loitering Interceptor for Surface-to-AirMissile

Abstract- The increasing prevalence of agile and low-signature aerial threats, such as Unmanned Aerial Vehicles (UAVs), necessitates the development of advanced and flexible air defense systems. Conventional Surface-to-Air Missiles (SAMs) are often limited by short engagement times, while existing loitering munitions lack the high-energy performance required for certain intercept scenarios. This paper presents the conceptual design and critical analysis of a novel loitering interceptor that synergistically integrates a throttleable hybrid rocket propulsion system with a mission-adaptive airframe featuring morphing fins. The methodology involves the theoretical design of a GOX/HTPB-based hybrid motor capable of operating in both high-thrust boost (50 N) and low-thrust loiter (5 N) modes. Computational Fluid Dynamics (CFD) is used to evaluate the aerodynamic performance of the missile in both stowed and deployed fin configurations, confirming the aerodynamic feasibility of a low- speed loiter phase. This paper extends the conceptual design by conducting a critical analysis of the key technical challenges, including propulsion control and stability, aero-structural dynamics, and the formidable guidance and control problem presented by the morphing transition. Keywords: Loitering Munition, Hybrid Rocket, Morphing Aerodynamics, Surface-to-Air Missile, UAV, Guidance and Control, Aero-structural Dynamics.