Test Methods for Short-range Lethality Evaluation of Full-scale Hypersonic Kinetic-energy Missiles

Lethality evaluation tests of anti-armor missile systems require flight-test of tactical missiles against threat targets under highly controlled impact conditions. Variables such as terminal dive angle, impact velocity, missile orientation at impact, hit-point on the target, and shot-line through the target all must be carefully controlled and documented to properly evaluate and analyze the damage caused and extrapolate this data to other impact conditions. Development missile systems have difficulty achieving control of the impact conditions at early stages in the program due to immature or nonexistent missile guidance technologies and hardware. Lethality data is traditionally generated through a combination of subsystem testing and predictive analysis. This approach has proven acceptable for traditional antiarmor missile systems, but fails to capture the damage mechanisms or damage levels produced by hypervelocity kinetic energy missiles. The high velocity requirements of kinetic-energy missiles prevent the use of test facilities and test methods traditionally utilized in the development of anti-armor missiles and analytical tools do not fully capture target damage effects, therefore combining subsystem test data with predictive analyses is not an option. Kinetic energy missiles require significant range to achieve full velocity where efficient penetration is achieved. However, these missiles will be tactically utilized in engagements at much shorter ranges. The missile will be accelerating at impact in these short-range scenarios, therefore the rocket motor is thrusting and contains unburned propellant, the quantity decreasing as engagement range increases. This ever-changing missile configuration adds to the difficulty in conducting shortrange impact tests since each engagement range requires a different missile configuration to properly represent tactical conditions. This paper will present and discuss two methods of conducting impact tests and generating lethality data for development of kinetic energy missile systems for a variety of missile mass properties, targets, and impact velocities. The first method to be discussed utilizes a highspeed sled track. This method employs large rocket motors to accelerate a multi-stage sled-train to the desired velocity. The missile simulant is separated from the sledtrack and flies a short distance to the target while the other sled hardware is diverted below the target to prevent additional target damage. This method requires conducting flyout tests to determine the flight dynamics of each different velocity or missile configuration. This method has been proven to yield hit-point accuracies tighter than has been demonstrated with tactical guided missiles and can be tailored to accommodate large or small missiles. The second method to be discussed involves utilizing high-tension ropes to guide the missile to the desired hit-point. This method has recently been developed at Redstone Arsenal, AL and provides a costeffective alternative that can be adapted to a wide variety of engagement ranges and impact angles with minimal hardware alteration. This method employs multiple highstrength high-tension ropes stretched between a tower at the launch point and the target. The missile simulant “rides” the ropes, propelled by a rocket motor, to impact at the desired hit-point on the target. Velocity and unburned propellant at impact are controlled by flight distance. The ropes are terminated either on the surface of the target (armor targets) or extend through the face of the target (wall targets) to control both the hit-point and impact orientation with respect to the target. The trajectory is tightly controlled by the tension in the ropes, which also allows for more accurate in-flight data collection. The missile size that can be tested with this method is currently limited to smaller (less than 100 pounds at launch) systems, but future development may address this scenario if need justifies. Report Documentation Page Form Approved