The M109A7 Self-Propelled Howitzer has arrived at the Ordnance School

By Levione StoneFebruary 26, 2021

Students inspect the Paladin Electrical Servo Amplifier (PESA) high voltage compartment of the M109A7 for damaged cables as part of the 91P Self-Propelled Artillery Systems Maintainer course at the U.S. Army Ordnance School, Fort Lee, Virginia. This exercise familiarizes students with the complex cable system and the safety parameters required when servicing high voltage components.
1 / 2 Show Caption + Hide Caption – Students inspect the Paladin Electrical Servo Amplifier (PESA) high voltage compartment of the M109A7 for damaged cables as part of the 91P Self-Propelled Artillery Systems Maintainer course at the U.S. Army Ordnance School, Fort Lee, Virginia. This exercise familiarizes students with the complex cable system and the safety parameters required when servicing high voltage components. (Photo Credit: Sgt. 1st Class Christopher M. Robbins) VIEW ORIGINAL
The M992A3 Carrier Ammunition Tracked (CAT) in the maintenance bay at the U.S. Army Ordnance School, Fort Lee, Virginia.
2 / 2 Show Caption + Hide Caption – The M992A3 Carrier Ammunition Tracked (CAT) in the maintenance bay at the U.S. Army Ordnance School, Fort Lee, Virginia. (Photo Credit: Sgt. 1st Class Christopher M. Robbins) VIEW ORIGINAL

FORT LEE, Va. - The M109A7 has arrived at the United States Army Ordnance School (USAOS) as part of the Army-wide fielding. The USAOS received its first two sets of M109A7s and M992A3s after many production delays and scheduling conflicts.

“We are excited to include both the M109A7 and the M992A3 in our program of instruction,” said Joseph W. Kirby, the USAOS Director of Training. “Our entry level 91Ps [Self-Propelled Artillery Systems Maintainers] are now training on advanced on-board electrical systems that will increase lethality on the battlefield.”

According to the original equipment manufacturer (OEM), the Paladin M109A7 Self-Propelled Howitzer (SPH) and M992A3 Carrier Ammunition Tracked (CAT) is the latest in the M109 family of vehicles, which serve as the primary indirect fire support system for Armored Brigade Combat Teams (ABCT).

The OEM states that the Paladin M109A7 uses the existing main armament and cab structure of M109A6 but replaces the vehicle’s chassis components - including the engine, transmission, final drives, suspension and track - with modern components common to the M2/M3 Bradley Infantry Fighting Vehicle. The commonality with ABCT systems offsets sustainability costs while improving chassis structure and M109A7 survivability.

The M109 SPH has been in the Army’s inventory for over 55 years, and this is the most significant modification to date. As expected with the integration of new systems, there is a steep learning curve. This is especially true when it comes to the Army’s most complex combat systems.

The Ordnance School, in collaboration with the Fires Center of Excellence and maneuver battalions currently using M109A7, has identified a variety of solutions to enhance the training of Self-Propelled Artillery Systems Maintainers (91P).

By leveraging 20 hours of existing time within the program of instruction (POI) and focusing on critical readiness drivers, A7 tasks were incorporated into the curriculum the first quarter of fiscal year 2021.

On October 5, 2020, the Ordnance School started training high voltage awareness, vehicle overview and driver's station familiarization elements as part of the M109A7 POI.

The M109A7 is the first ABCT vehicle built with a 70kW high voltage system, which replaces the hydraulic cab drive system and enhances electronic ammunition handling and air-conditioning.

To maintain high voltage systems, the Self-Propelled Artillery Systems Maintainer will now receive high voltage awareness training and must achieve both Level I (operator) and Level II (maintainer) standards to graduate.

Students will also learn about the major upgrades to the driver’s compartment with a focus on the enhanced diagnostic capability. The onboard diagnostics and health management system allows the maintainer to collect real-time data from connected subsystems.

When the vehicle is started, the automated test system performs self-diagnostics to determine operational status. From the driver’s station, students can check the software version and maintenance tasks with access to the onboard Interactive Electronic Technical Manuals (IETM).

As the M109A7 continues through fielding, the Ordnance School will progressively increase the amount of time students train on the platform. The 91P course and critical task list will continue to undergo major changes based on feedback from operational units. The changes to the training environment will save units valuable resources such as time, manpower and money.

The modernized M109A7 is here.