America's artillery dilemma: Searching for a modern successor
The most powerful army in the world lacks modern artillery. The United States still relies on the M109 self-propelled howitzers, which were developed over 60 years ago. Despite efforts spanning more than a quarter of a century, the Pentagon has yet to identify a successor, and work on future artillery systems is still ongoing. What is known about these systems?
The importance of artillery on the modern battlefield cannot be overstated — it accounts for 60-70% of casualties in both personnel and equipment. Its destructive potential surpasses that of aviation, mines, or combined losses from direct combat.
Therefore, the Pentagon has been striving for years to achieve significant modernisation and introduce generational artillery changes within the American military. Although these attempts have been ongoing for over 25 years, they have yet to yield tangible results.
The M109 howitzers were introduced into service in the 1960s and have been modernised over subsequent decades. The most significant upgrade, which greatly enhanced the capabilities of this weapon, was the development of the M109A6 Paladin variant in the 1980s. The Paladin, produced in a quantity of 950 units, was introduced into service in the late 20th century and has become a cornerstone of American tube artillery.
The Crusader Programme
In parallel with the modernisation of existing artillery, the United States began work on futuristic combat systems — tanks, infantry fighting vehicles, and self-propelled artillery. The dissolution of the USSR led to the abandonment of some of these plans, but the awareness that American artillery was ageing meant that the Crusader programme was not discarded.
It was a very ambitious programme to build the artillery of the future, originally planning to use liquid propellant instead of a powder charge. Ultimately, the XM2001 Crusader took a somewhat more traditional form — a 155mm calibre gun mounted on a tracked chassis, sharing the drivetrain with the Abrams tank.
Thanks to the use of an autoloader, the crew consisted of only three people, and the new system's firing range reached 25 miles (approximately 40 kilometres) — comparable with the leading artillery systems of those years. Ultimately, the Crusader programme was cancelled, and the army was advised to purchase the German PzH2000 or further modernise the Paladin. The latter was ultimately modernised to the currently used M109A7 variant.
The ERCA Programme
Based on this variant, the next developmental programme — ERCA — aimed to create new-generation artillery. The beginnings were very promising: the towed, ultra-light M777 howitzer, using new propellant and new rounds, doubled its firing range from 19 miles (around 30 kilometres) to 37 miles (almost 60 kilometres). A similar effect was planned for self-propelled artillery.
Within the ERCA programme, a series of successful tests were conducted — the experimental XM1299 howitzer, with a barrel length increased from 39 to 58 calibres (from about 6 metres to nearly 9 metres), fired over a distance of 43 miles (roughly 70 kilometres), a range that — with further progress — was intended to increase even to 62 miles (around 100 kilometres).
This was achievable thanks to the use of new propellant, improved combustion control, and the development of projectiles with additional propulsion. When combined with a longer barrel, allowing for a higher muzzle velocity, this provided a significant increase in firing range, although it also caused new issues, such as faster barrel wear.
Successful trials were also conducted with innovative projectiles like the XM1155-SC with rocket propulsion and a Raytheon-developed ramjet-powered projectile, which hit a target over 62 miles (about 100 kilometres) away during a test. Despite promising results, the ERCA programme was cancelled due to budget constraints.
The SPH-M Programme
However, the Pentagon has not given up on modernising its artillery. For this purpose, the SPH-M (Self-Propelled Howitzer Modernisation) programme was announced. Five leading manufacturers were invited: American Rheinmetall Vehicles, BAE Bofors, Hanwha Defense USA, General Dynamics Land Systems, and Elbit Systems USA.
Participants are to present their own solutions — not only complete artillery systems but also components that the United States could potentially assemble into their own future artillery system, bypassing the stage of prolonged trials and the "teething problems" of developing new weapons.
This is not only about the chassis but particularly the turret with its armaments, an extension of the British AS90 turret system. This has been withdrawn from service in the UK this year.
