Developed by the U.S. Army to be fired from the M270 Multiple Launch Rocket System (MLRS) or M142 High Mobility Artillery Rocket System (HIMARS) launchers, the MGM-140 ATACMS (Army Tactical Missile System) is a short to medium-range ballistic missile. Carrying either a high explosive unitary warhead or dual-purpose cluster submunitions, it replaced the MGM-52 Lance, a missile assigned to corps level support with nuclear warheads. As Lance missiles reached the end of their storage lives, and precision-guided munitions superseded tactical nuclear weapons, a replacement was needed.
ATACMS is now in its fourth version. 32 of the "A" version were used in Operation DESERT STORM, as a long-range weapon, directly responsive to ground commanders, for attacking high-value targets such as missile sites and command posts, beyond the range of cannon artillery such as the M109 howitzer. This missile had 100mi/165km range with moderately precise inertial guidance; the guidance limitation essentially required the area effect of cluster submunitions. It ties into command and control through the Advanced Field Artillery Tactical Data System.
Precision considerably increased with the "B" model, which added GPS. With increased precision, the warhead size was reduced yet range was increased to 185mi/300km. This version went into service in 1998.
The "C" model, called ATACMS Block II, was redesignated as a long-range antitank weapon, carrying the Brilliant Anti-Tank (BAT) munition. The missile version was canceled in 2003 as large-scale tank warfare became less likely, but the BAT is continuing as a hard-target weapon to be carried by unmanned aerial vehicles.
Most recently, the "D" model was a general upgrade of the "B", still carrying cluster submunitions at even greater range. With continued guidance improvements, and the political sensitivity of cluster munitions, the "E" model introduced a 500 lb high-explosive warhead. This is essentially the same WAU-23 warhead used on the AGM-84 SLAM air-to-surface missile.
A longer-range hard-target-penetrator variant has been in design, but production continues of the B/D and E models, both in service. They continue to be fired from the M270, which has two positions for weapons canisters. The sealed canisters contain either one ATACMS, or six of the shorter-ranged unguided M26 rockets, or guided M30 cluster submunition or XM31 unitary missiles.
- Andreas Parsch, Lockheed Martin (LTV) MGM-140 ATACMS
- The Army Tactical Missile System (Army TACMS) Family of Munitions (AFOM): Tactics, Techniques and Procedures (TTP), Field Artillery School, U.S. Army, Special Text 6-60-30