The M109 is an American-made self-propelled 155 mm howitzer, first introduced in the early 1960s. It was upgraded a number of times to today’s M109A6 Paladin
According to information published by the United States army on August 29, 2022, the U.S. Army Futures Command continues its modernization efforts with long-range precision fires, its cross-functional teams along with U.S. Army Yuma Proving Ground are working to develop new capabilities to increase the rate of fire of the Extended Range Cannon Artillery or ERCA.
The ERCA system’s development emerged as a formal research effort – known as an “STO” for Science and Technology Objective – following a 2013 study that assessed next-generation artillery. According to Lee, the main takeaway from the onset of the effort was that significantly increased range coupled with increased rates of fire was technologically within reach, and it would be a “game changer” for cannon artillery.
The ERCA (Extended Range Cannon Artillery) is considered the signature effort within the U.S. Army’s top Modernization Priority, Long Range Precision Fires. The Long Range Precision Fires Cross Functional Team has set plans in motion for a two-phased capability improvement by first providing the Soldier a self-propelled howitzer with increased range and lethality, and then providing an increase to rate-of-fire.
The ERCA effort rose to prominence in November 2018 when an earlier variant of the ERCA system fired the XM1113 Rocket Assisted Projectiles to just beyond 70 kilometers at Yuma Proving Ground. They were the farthest-reaching shots ever made by U.S. Army howitzers at the time, and more than double the reach of currently fielded Army artillery systems.
In November 2018, an earlier variant of the ERCA, the XM1299 howitzer, fired projectiles out to 72 kilometers at Yuma, the farthest-reaching shots ever made by U.S. Army howitzers, and more than double the reach of currently fielded Army artillery systems.
The ERCA armaments are fitted on an M109A7 “Paladin” tracked armored chassis to form the self-propelled ERCA system with an optimized cab and full-capacity autoloader. The M109A7 SPH Paladin 155mm Self-propelled howitzer is an upgraded version of the M109A6 Paladin. It is armed with a 39-caliber 155mm M284 cannon, which is fitted with an M182A1 gun mount and has a range of 24 km using unassisted rounds or 30 km using assisted rounds.
Along with the autoloader, prominent elements of the ERCA program include the XM1113 Rocket Assist Projectile and XM659 Stub Charge, which have been formally transitioned and are now managed by Project Manager Combat Ammunition Systems (PM CAS). There are also several versions of the “Supercharge” in various stages of development to support an increased range capability.
The cannon features a sliding block breech built to withstand the immense pressure of the supercharge and a cannon tube made with new alloys formed to a 30-foot length, which enables a projectile’s velocity to continue increasing inside the cannon tube before exiting.