The Patriot PAC-3 is an entirely new missile, derived from the ERINT interceptor, which is intended to counter theater-class ballistic missile threats using hit-to-kill intercept. The PAC-3 missile is fired from the same launcher as earlier versions of Patriot, although eight of the smaller PAC-3 missiles are carried in each firing unit, versus four each of the earlier versions. Six battalions are planned for deployment beginning in late 1999.
The Navy Area Defense enhancement to the AEGIS/Standard Missile air defense system provides a tactical missile defense capability comparable to that provided by PAC-3. The modified Standard Missile 2 Block IV missiles will be deployed on Ticonderoga-class cruisers and Arleigh Burke-class destroyers equipped with the powerful AEGIS air and missile defense radar. A limited operational capability will is planned for 1999 and an initial operational capability is planned for 2001.
Medium Extended Air Defense System (MEADS), formerly known as CorpSAM, is an international effort to develop a replacement for the widely deployed HAWK anti-aircraft system. This highly mobile system, to be deployed with forward deployed and maneuvering ground forces, is intended to provide omni-directional coverage against the full range of air-breathing threats [both aircraft and cruise missiles]. The United States, Germany, and Italy are partners in MEADS, following a decision in early 1995 by France to withdraw from the program.
These programs are relatively modest in cost, have limited technical risk, and are intended to counter existing threats from ballistic missile with ranges of hundreds of kilometers. Other more ambitious programs pose greater challenges in countering potential future emerging theater threats.
The Army's Theater High Altitude Area Defense [THAAD] is intended to provide extended coverage, engaging incoming missile at ranges of up to several hundred kilometers, versus the tens of kilometers provided by the previously discussed systems. This hit-to-kill interceptor could thus provide multiple engagement opportunities against missiles with ranges of hundreds of kilometers, and enhanced capabilities against future threats from missiles which might have ranges of thousands of kilometers. THAAD missiles are intended to actually collide with the target ballistic missile, rather than destroying it by exploding nearby, as fragmentation warheads do. Final guidance to the target is provided by an infrared seeker on the kill vehicle. The interception of a hostile ballistic missile is intended to occur outside the earth's atmosphere, or high in the atmosphere. The range of the THAAD system is to be approximately 200 km horizontally and 150 km vertically. In order to provide an emergency capability to counter a small number of missiles, plans call for fielding about 40 THAAD missiles and associated radars by 1999. Each THAAD battery would include 9 launchers and 150 missiles.
Based on AEGIS-equipped ships, the Navy's Theater Wide long-range interceptor system will provide wide area coverage against a wide range of threats, including ascent phase intercepts where the ship's mobility permits such engagements.