GMARS: The future of high-mobility rocket artillery in Europe

One of the key weapon systems used by both sides during the war in Ukraine is the artillery rocket system. The American M142 HIMARS launchers used by Ukrainians have gained particular fame. These truck-mounted container launchers can hold six GMLRS rockets or one ATACMS rocket. This number can sometimes be insufficient, which is why the German company Rheinmetall and Lockheed developed the GMARS concept—a rocket launcher with double the firepower of the classic HIMARS.

Germany currently uses similar systems designated as MARS II (Mittleres Artillerieraketensystem II). This is a version of the American M270 MLRS rocket system intended for Germany. The launcher is mounted on a tracked chassis and entered service at the turn of the 1980s and 1990s. According to estimates, about 40 launchers of this type remain in service, with several dozen more in storage. These are systems proven in combat and mobile, but they are aging and need successors. The GMARS is intended to be the solution.

The main difference from the MARS II is the use of a wheeled chassis based on the high-mobility MAN RMMV HX2 8×8 truck. Compared to the M142 HIMARS, the main difference is the use of a double launch container (as in MARS II), doubling the number of rockets that can be fired. Thus, it combines the firepower of MARS II with the mobility of HIMARS, enhanced with the latest types of ammunition and technological solutions.

The launcher is 10 metres long, 2.4 metres wide, and 4 metres high in the proposed configuration. The vehicle's unladen weight is 31,100 kilograms, and its combat weight is 42,200 kilograms. On a paved road, the truck can accelerate to 100 kilometres per hour, and its range is 700 kilometres. Thus, the launcher features high tactical mobility, and the 8×8 system offers significant off-road capabilities, though not as high as that of a tracked carrier.

A significant advantage of the GMARS is its ability to quickly open fire and then change position to avoid becoming a target for counter-battery fire. Taking a position to open fire does not require deploying any side supports. It only requires stopping the vehicle and raising the launcher. Loading ammunition is also fast, as it involves removing empty containers with a crane and loading full ones. The crew consists of two people, and the entire operation is conducted from inside the cabin.

The launcher is compatible with all types of launch containers and ammunition used in MLRS and HIMARS systems. Furthermore, in the future, it can be integrated with missiles currently in development and with 122 mm rockets produced to Eastern standards.

The M31 GMLRS-U (Unitary) rocket has an 89-kilogram high-explosive warhead. It is guided by an inertial navigation system corrected by GPS. If the GPS signal is jammed, its accuracy decreases but remains very high, within a range of several dozen metres. The rocket’s fuse operates in two modes: contact and delayed.

The M30A1 GMLRS-AW (Alternative Warhead) rocket is armed with a 89-kilogram fragmentation warhead. It uses the same guidance system as the M31 rocket. Upon detonation, the warhead splits into 176,000 preformed fragments in the form of tungsten balls with diameters of 3.3 millimetres and 5.6 millimetres. Additionally, an extra projectile at the front of the warhead fills the gap created during the warhead's fragmentation. The rocket has a proximity fuse that triggers detonation 10 metres above the target, ensuring the maximum number of tungsten balls hit the designated area.

The M57 ATACMS ballistic missile has a range of 300 kilometres and is equipped with a 221-kilogram high-explosive warhead WDU-18/B. The warhead is triggered by either a contact or proximity fuse. The missile is intended to destroy stationary point targets or small group targets while minimizing collateral damage. These can include command posts, logistics centres, warehouses, ground-to-ground and anti-aircraft rocket launchers, or radar stations. Like the previous rocket, it is guided inertially with GPS correction.

The second type of ballistic missile is the Precision Strike Missile (PrSM). It has a smaller diameter than the ATACMS, allowing two missiles of this type to fit in a single container. The PrSM has a range of about 500 kilometres. Besides GPS guidance, the PrSM will also use a self-guiding head in the terminal phase, enabling it to hit moving targets such as vehicles or warships. This is just the beginning of new capabilities implemented in PrSM in subsequent development stages. The next version of PrSM is expected to receive a multi-band radar and an infrared-guided head, and its range will be extended to 1,000 kilometres.

If such a version is eventually developed, there is also a plan to enable the launch of JASSM-ER cruise missiles from these launchers. This would require adding a starter motor to the missile, allowing it to accelerate to the required speed and gain the appropriate altitude. This is currently only a concept but is being considered by the U.S. Congressional Budget Office, among others. Funds for this project's development have yet to be determined.

GMARS is the only wheeled chassis launcher capable of carrying two MLRS/HIMARS family launch containers. The companies involved in the project hope that it will attract interest from Germany and other European users of the M270 system, including the Netherlands, the United Kingdom, and Italy.