The Multiple Launch Rocket System (MLRS), formerly known as the General Support Rocket System (GSRS), is an armored, self-propelled, tracked vehicle mounted, rocket artillery system providing mobile tactical and long range artillery rocket support for ground forces.

MLRS consists of two major, mechanical units and an integrated Fire Control System (FCS.) A stretched-out chassis variation of the Bradley Infantry Fighting vehicle, powered by a turbine engine, forms the M993 Carrier Vehicle. The vehicle is mounted with an M269 Launcher Loader Module (LLM.) The LLM carries a standard payload of two 'pods' containing six rockets each. The FCS is operated from inside an armored, negatively pressurized, three man cab. The FCS uses known elevation and heading information while automatically correcting for launcher cant angles and ambient temperature to obtain correct elevations for launching rockets and missiles. The two units, the M993 Carrier Vehicle and the M269 Launcher Loader Module, combined with the automated Fire Control System, form the M270 Self-Propelled Launcher Loader or M270 SPLL.

The M270 MLRS is powered by a turbine engine pushing the rocket launcher to cross country speeds in excess of 40 mph and a navigational range of 300 miles. This engine is the same turbine behind the monstrous M1A1 Abrams Main Battle Tank and is powerful enough to literally pull a person’s blood through their skin. The MLRS is also capable of navigating 60 degrees of slope and climbing one meter high obstructions. An MLRS SPLL carrying a combat load of 12 M26 rockets weighs in at approximately 53,000 pounds or 26.5 tons.

A three person crew operates the MLRS: A Driver, Gunner and Track Chief. Soldiers are trained, tested and certified to perform the duties associated with all three positions. The soldier’s cross training in MLRS is crucial, because the weapon system is designed in a manner making it possible for any single crewmember to successfully load, launch and re-deploy the MLRS system, maintaining survivability in a combat environment.

MLRS is a versatile weapons platform capable of launching a wide variety of conventional warhead packages, together referred to as the MLRS Family of Munitions (MFOM.) Warhead assemblies range from 'dumb,' unguided packages to more advanced 'smart,' guided warheads able to directly engage enemy targets. The anchor of the MLRS Family of Munitions (MFOM) is the M26 Rocket. Rockets come pre-loaded in a pod structure holding six rockets each, also known as 'six packs.' The M270 MLRS holds two pods (12 rockets) and can fire ripples of one to twelve rockets, at up to twelve different targets, in less than 60 seconds. Each M26 rocket is 13 feet long with a range exceeding 30 kilometers.

An M26 warhead contains 644 grenade sized, high explosive, shape charge munitions. As a rocket nears a target, the warhead splits in an air-burst event, ejecting sub-munitions in a pattern to attain maximum saturation and coverage of a target area. The M26 warhead is designed to be most effective against troop concentrations, supply depots, unarmored or lightly armored vehicles and enemy weapons emplacements, particularly enemy field artillery.

While rockets streak towards their target(s), MLRS crews re-deploy the launcher before enemy forces can determine a launcher's firing position. This rapid redeployment virtually eliminates enemy, counter-battery fire as a viable threat: A battlefield survivability philosophy known as the “Shoot and Scoot” method.

At any given time, there are more than 60,000 rocket pods, containing various varieties of the MLRS Family of Munitions, positioned in many places around the globe for rapid access by U.S. Field Artillery forces and the timely delivery of those munitions on their respective targets. Some of those positions include, but are not limited to: The United States, Germany, Italy, Kuwait, Korea, Several Prepositioned Supply Ships and other storage areas.

The MLRS also launches the much larger ATACMS (Army Tactical Missile System) missile. The M269 Launcher Loader Module (LLM) on the MLRS platform can carry two pods, each containing one ATACMS missile. ATACMS missiles have a range exceeding 100 kilometers (62 miles) and can carry a much larger warhead package. The MLRS can also launch the Tacit Rainbow, a ground launched, cruise missile package specifically designed for use against enemy radars.

MLRS was first fired in combat during Operation Desert Storm. The MLRS weapon system's initial trial took place on the evening of February 13, 1991 in the geographical area known as Wadi al Batin, just west of the Saudi Arabia, Iraq, Kuwaiti tri-border area. The historical fire mission was carried out by 'A' Battery 21st Field Artillery, MLRS (A/21) of the famous 1st Calvary Division. A/21 positioned all 10 of their launchers along a 3-kilometer stretch and fired more than 100 M26 rockets onto several targets in less than 60 seconds.

During the course of the Persian Gulf War, A/21 FA, MLRS fired 550 rockets, the second most for a single MLRS Battery. The most MLRS rockets fired by a single MLRS Battery was achieved by 'A' Battery, 1st Battalion, 158th Field Artillery (MLRS), Oklahoma Army National Guard. The 1/158 FA battery fired 699 total rockets during pre-invasion raids and the ground war. Together, U.S. Army MLRS units fired more than 17,000 rockets and 32 ATACMS missiles against Iraqi howitzer and rocket battalions, air defense artillery (ADA) battalions, command and control facilities and logistics facilities. MLRS proved to be extremely effective and very dependable throughout the Persian Gulf War. The enormous success of MLRS in combat was succinctly characterized by VII Corps Commander, LTG Fred Franks, when asked about the devastating weapon system; Franks stated, "MLRS is gangbusters."

British forces also fired the MLRS in combat for the first time during Operation Desert Storm. According to LTC Peter Williams, Commander of Britain's 39th Royal Artillery Regiment in Saudi Arabia, "MLRS is the decisive battle winner. We call ourselves the Grid Square Removal System because the rockets from each launcher can take out a square kilometer of the map." Perhaps the most telling nick-name given to MLRS during the Gulf War, was coined by the Iraqi troops who had to endure long hours of bombardment by coalition MLRS units. Captured Iraqi soldiers referred to the grenades dispersed by the MLRS as "Steel Rain." The deadly downpour helped blast a significant, psychological hole in Iraqi defensive positions in Kuwait. This crushing, psychological defeat translated into 1,000's of Iraqi soldiers surrendering, rather than endure further punishment from the desert storm's "Steel Rain."