The ATACMS (Army TACtical Missile System) is a US short-range ballistic missile system, and is the only ωєαρσи of this type still operational in the US military. It is also designated M39 by the US Army, and its DoD designation is MGM-140. This ωєαρσи complements the US military’s rocket artillery systems, effectively closing the gap between artillery systems used by ground forces, and the aircraft and cruise missiles used by air and naval forces.

In fact, it is not entirely accurate to classify the ATACMS as a “ballistic missile”, as this classification implies that the projectile flies on a ballistic trajectory. While the ATACMS does assume a ballistic arc to its target, it also performs a series of rapid and sudden turns and course corrections on the way to its aimpoint. This is a deliberate function of the ATACMS, as this seemingly erratic flight behavior makes it exceptionally difficult to track or intercept. This class of ωєαρσи is thus widely referred to as a “quasi-ballistic missile”, though the US Army has also referred to the ATACMS as a “maneuvering missile”.

This ωєαρσи is not unique in being a quasi-ballistic missile, however. Numerous other ballistic missiles have similar capabilities, including the DF-21S (CSS-5), Hades, OTR-23 Oka (SS-23 Spider), LORA, and Dhanush. The OTR-21 Tochka (SS-21 Scarab) was the first ωєαρσи of this type to achieve operational service.

The requirement for what would become the ATACMS was identified in 1980, and the program was established in 1982 as the JTACMS (Joint Tactical Missile System), when the DoD merged two similar programs of the US Army and US Air Force. Shortly after the request for proposals was issued to industry in 1985, the USAF withdrew from JTACMS; it thus became an Army project, and was thus re-named ATACMS. The LTV Aerospace company won the bid, and was awarded a contract in May of 1986 to develop and manufacture the ATACMS system. The first flight of the XMGM-140A missile was achieved in 1988, with low-rate initial production initiated later that year. After additional testing and refinements, the ATACMS officially entered active service with the US Army in January of 1991. Production of the ATACMS changed hands twice, and as of 2015, it is a Lockheed Martin product.

The ATACMS had entered service just in time as well, as the US Army was on the verge of ωαя with Iraq. During Operation Desert Storm, a total of 32 were launched in combat. This ωєαρσи was used much more extensively in Operation Iraqi Freedom, during which more than 450 were launched in anger. To date, more than 560 ATACMS’ have been launched in combat.

There is no dedicated launch platform for the ATACMS. It is instead launched from either the M270 MLRS or the M142 HIMARS, from which the more familiar 6-cell 227 mm rocket launcher is replaced with a single launch tube for the missile. The MLRS can carry a single ATACMS and 6 227 mm rockets, or two ATACMS missiles, while the HIMARS’ launcher only has enough space for either a 6-cell 227 mm rocket launcher or a single ATACMS. See the pages on the MLRS and the HIMARS for more details.

The original MGM-140A model of the ATACMS employs INS guidance, while subsequent models also utilize GPS to improve their accuracy. These guidance systems reportedly give the ATACMS a CEP (Circular Error Probable) of between 10 m and 50 m, depending on the model and the circumstances of the fire mission. The total accuracy of the ATACMS is much more difficult to judge, however, as CEP only measures the tightest grouping of half the rounds fired in testing, and doesn’t factor-in the location of the aimpoint, the location of the target, nor the entire area across which the rounds impact. This is nonetheless of little concern with the variants carrying submunition warheads, and frontline combat reports suggest the MGM-168A is quite accurate.

Three different types of warheads are used on the operational models of the ATACMS. The MGM-140A contains 950 M74 APAM (Anti-Personnel Anti-Material) submunitions, which are scattered in mid-air during the final stretch of the missile’s terminal phase. Depending on how far from the target the missile is set to release its submunitions, they can potentially saturate an area of up to 33 000 m2, with each submunition having a casualty radius of 15 m. The MGM-140B disperses the same M74 submunitions, but carries roughly one-quarter as many. The MGM-168A carries a large unitary warhead designed to greatly increase damage to point targets, while minimizing collateral damage. All three of these warheads are most effective when employed against soft targets.

All ATACMS models are propelled by a solid fuel rocket motor, with the effective range varying between the three operational models. The shortest-range model is the original MGM-140A, with an effective range of 128 km. The reduction of the warhead’s weight in the MGM-140B has resulted in an improved range of 165 km, while the newer MGM-168A has a range of 300 km.

The ATACMS has never employed an NBC warhead, which is likely why this ωєαρσи’s development was permissible under the 1987 Intermediate-Range Nuclear Forces treaty (or INF treaty). Similarly, concerns that this missile might otherwise violate the MCTR (Missile Technology Control Regime) treaty has resulted in the longest-range variant being limited to 300 km.

Production of the ATACMS ceased in 2007, by which time 3 700 were completed, and has thus far not resumed. However, development is still ongoing, with emphasis on improving accuracy and submunition reliability. A successor is planned by the US Army, but as of 2015, no solid details have emerged.

According to the Federation of American Scientists, a single round costs approximately $820 000. This ωєαρσи’s known operators are Bahrain, Greece, South Korea, Taiwan, the United Arab Emirates, and USA.