Sigma 155mm Howitzer.

The SIGMA Mobile Tactical Cannon, or MTC, is the U.S. configuration of the SIGMA family of 155mm self-propelled howitzers developed by Elbit Systems. Elbit America is offering the system to the U.S. Army under the Self-Propelled Howitzer Modernization program. The SIGMA MTC is intended to support U.S. Army maneuver formations. Its mobility, operating range, and firepower are configured to support a Stryker Brigade Combat Team, an Infantry Brigade Combat Team, or to operate in a general support artillery role.

The U.S. SIGMA proposal began to be presented publicly in 2023. In November 2023, Elbit America was already describing SIGMA as its Next Generation Howitzer for the "Army of 2030 and beyond." At the time, the system was presented as a response to the challenges faced by towed artillery units in maintaining continuous fire support for Infantry and Stryker Brigade Combat Teams during rapid movements and large-scale combat operations. Elbit America published a dedicated presentation of the system on December 12, 2023, based on an article originally published in the Field Artillery Journal on November 21, 2023.

The U.S. program entered a new phase in 2024 with the launch of demonstrations for the Self-Propelled Howitzer Modernization, or SPH-M, program. On October 14, 2024, the U.S. Army announced the selection of Elbit Systems USA as one of five companies contracted to provide systems for performance demonstrations, alongside American Rheinmetall Vehicles, BAE Bofors, Hanwha Defense USA, and General Dynamics Land Systems. This approach followed the termination of the Extended Range Cannon Artillery rapid prototyping effort, with the U.S. Army shifting toward the evaluation of mature industrial solutions available in the United States and abroad. Initial SPH-M demonstrations were scheduled to begin in November 2024.

Elbit America subsequently presented SIGMA to the U.S. public at the AUSA 2024 Annual Meeting, where the system was displayed as a candidate for the U.S. Army's future self-propelled artillery requirements. The company continued demonstrations and testing of the system under the U.S. program during 2025 and 2026.

In March 2026, Elbit America displayed the SIGMA Mobile Tactical Cannon at the AUSA Global Force Symposium in Huntsville, Alabama, marking the transition from the Next Generation Howitzer concept to a physically integrated U.S. configuration presented as a candidate for the SPH-M program. On June 2, 2026, Elbit America and Anduril Industries announced a strategic cooperation agreement to jointly offer the SIGMA MTC to the U.S. Army. Elbit America is responsible for integration and production of the land system, while Anduril contributes capabilities in C5ISR, battle management, and autonomy software.

The SIGMA MTC is produced in North Charleston, South Carolina. Production is supported by a U.S.-based industrial and supply chain. Elbit America documentation states that the system is currently in production in the United States. SIGMA is related to the ROEM developed by Elbit Systems for the Israel Defense Forces. ROEM is the Israeli configuration of this artillery family, while the SIGMA MTC is adapted to U.S. requirements. Both systems use an architecture based on a 155mm/52-caliber gun, a 10x10 wheeled platform, an uncrewed turret, and a high level of automation.

The SIGMA MTC uses an automated turret that allows a three-soldier crew to conduct firing operations from inside the armored cabin. The system automates projectile handling, loading, and gun operation. Its automated magazine carries 40 projectiles. SIGMA uses an architecture in which gun laying, ammunition handling, fuze setting, loading, and firing operations are automated. General SIGMA documentation states that a reduced crew can conduct the complete fire mission from a protected cabin.

The system carries up to 40 projectiles in automated magazines. This capacity supports sustained fire missions while limiting the need for the crew to handle ammunition manually. The SIGMA MTC provides 360° firing capability without requiring the vehicle to be repositioned. This allows targets in different directions to be engaged without changing the orientation of the chassis. SIGMA documentation also identifies rapid transition into and out of firing positions as a means of reducing exposure to counter-battery fire.

The system can conduct Multiple Rounds Simultaneous Impact (MRSI) missions, allowing several projectiles fired sequentially on different trajectories to reach the same target at approximately the same time. Multiple SIGMA systems can also be connected through wired or wireless communications and controlled from a centralized command post. The SIGMA MTC is designed for shoot-and-scoot operations. Its automation and wheeled platform reduce the time required to enter a firing position, conduct a fire mission, and move to another location, limiting exposure to detection and counter-battery systems.