HEDI

American anti-ballistic missile. Two stage vehicle consisting of 1 x X-265 + 1 x X-271

The U.S. Army's HEDI (High Endoatmospheric Defense Interceptor) was an SDI (Strategic Defense Initiative) program for a lower-tier ballistic missile defense, a complement to the ERIS (Exoatmospheric Reentry Interceptor Subsystem) upper-tier system. Technology for an endoatmospheric hit-to-kill missile interceptor was tested by KITE (Kinetic Kill Vehicle Integrated Technology Experiment) test vehicles as part of the HEDI program. KITE was a rail-launched two-stage test vehicle using surplus Sprint ABM motors (Hercules X-265 and a Hercules X-271). A KKV (Kinetic Kill Vehicle) fitted with an infrared seeker, was protected under a shroud during the initial high-speed 200G acceleration through the lower atmosphere.

KITE-1 on 26 January 1990 was followed by the failed KITE-2 on 23 September 1991 and the final KITE-2A on 26 August 1992. The operational HEDI program had been cancelled in 1992, but the KITE flights tested various system components like seeker, guidance and control systems. No actual intercepts were attempted.

Historical Essay © Andreas Parsch

McDonnell-Douglas HEDI

The U.S. Army's HEDI (High Endoatmospheric Defense Interceptor) was an SDI (Strategic Defense Initiative) program for a lower-tier ballistic missile defense. As such it was to complement to ERIS (Exoatmospheric Reentry Interceptor Subsystem) upper-tier system.

No true HEDI missiles were built, but technology for an endoatmospheric hit-to-kill missile interceptor was tested by KITE (Kinetic Kill Vehicle Integrated Technology Experiment) test vehicles as part of the HEDI program. KITE was a rail-launched missile based on the older Sprint nuclear-armed ABM (Anti-Ballistic Missile). It was a two-stage solid-fueled rocket, powered by a Hercules X-265 and a Hercules X-271 motor. The KKV (Kinetic Kill Vehicle) was fitted with an infrared seeker, which was protected behind a shroud during the initial high-speed flight through the lower atmosphere. The KITE achieved an acceleration of over 200 G immediately after launch.

The first KITE test flight ("KITE-1") on 26 January 1990 was followed by a failed launch ("KITE-2") on 23 September 1991 and the second and last flight ("KITE-2A") on 26 August 1992. The operational HEDI program had been cancelled in 1992, but the KITE flights tested various system components like seeker, guidance and control systems. However, no actual intercepts were attempted.

Specifications

I have no data about the exact physical characteristics of the KITE test vehicle or the planned HEDI operational missile.

Main Sources

[1] Army Strategic Defense Command memorandum about "KITE-2A" test, 26 August 1992
[2] Gunter Krebs: Gunter's Space Page