America's outdated artillery: Challenges in finding successors
The most powerful army in the world faces a significant issue: its reliance on outdated artillery. The United States continues to use the M109 self-propelled howitzers, developed over 60 years ago. Despite efforts lasting over a quarter of a century, the Pentagon has not identified a suitable successor, and work on future artillery systems continues. What do we know about these efforts?
The importance of artillery on the modern battlefield can't be overstated—it accounts for 60% to 70% of casualties in both personnel and equipment. Its destructive potential surpasses that of aviation, landmines, or direct combat losses combined.
The Pentagon has been attempting a significant modernization of its artillery for years, aiming for generational changes in its military technology. Yet, despite efforts spanning over 25 years, no concrete results have been achieved.
Originally introduced in the 1960s, the M109 howitzers have undergone numerous updates over the decades. The most impactful change was the development of the M109A6 Paladin variant in the 1980s. With 950 units produced, the Paladin entered service in the 1990s and has become the cornerstone of American towed artillery.
The Crusader program
Alongside modernizing existing artillery, the U.S. also began developing futuristic combat systems, including tanks, infantry fighting vehicles, and self-propelled artillery. The dissolution of the USSR led to many of these plans being shelved, but aging artillery remained a concern, keeping the Crusader program alive.
This ambitious program aimed to create the artillery of the future, initially planning to use liquid propellants instead of conventional powder charges. Ultimately, the XM2001 Crusader featured a 155mm caliber gun on a tracked chassis, sharing its drivetrain with the Abrams tank.
The autoloader allowed the crew to be reduced to just three members, and the firing range was extended to 40 km (25 miles), competitive with top artillery systems of the time. Despite these advances, the Crusader program was canceled, and the U.S. Army was advised to either procure the German PzH2000 or continue upgrading the Paladin, which led to the current M109A7 variant.
The ERCA program
Building on this variant, the ERCA developmental program aimed to create next-generation artillery. Its start was promising: the towed, ultra-light M777 howitzer used new propellants and rounds to double its range from 30 km (19 miles) to 60 km (37 miles). A similar upgrade was intended for self-propelled artillery.
In the ERCA program, a series of successful tests were conducted. The experimental XM1299 howitzer, with a barrel extended from 39 to 58 calibres (about 6 metres to nearly 9 metres), achieved a firing range of 70 km (43 miles). With further progress, the range was expected to reach 100 km (62 miles).
This improvement was achieved through advanced propellants, improved combustion control, and projectiles with additional propulsion. The extended barrel allowed for higher muzzle velocity, significantly boosting the firing range but also introducing challenges like accelerated barrel wear.
Tests were also successful with innovative projectiles like the XM1155-SC, which featured rocket propulsion, and a Raytheon-developed ramjet-powered projectile, achieving targets over 100 km (62 miles) away in tests. Despite promising outcomes, budget cuts caused the ERCA program to be cancelled.
The SPH-M program
The Pentagon remains committed to modernizing its artillery. The SPH-M (Self-Propelled Howitzer Modernization) program has been announced. Five leading manufacturers were invited: American Rheinmetall Vehicles, BAE Bofors, Hanwha Defense USA, General Dynamics Land Systems, and Elbit Systems USA.
Participants are expected to present their own solutions—whether complete artillery systems or components that could allow the U.S. to assemble its own future artillery system, avoiding lengthy trials and the developmental challenges of new weapons.
