The M109A6 Paladin
is the current (as of 2003) modern self-propelled howitzer
in use by the armed forces of the United States
. A 'self-propelled howitzer
' is (as opposed to a towed howitzer) essentially a large artillery cannon mounted on an armored vehicle chassis
. Although it may superficially resemble an overgunned tank
, it is a quite different machine which performs a quite different job.
Artillery has been a specialty of the United States since before World War I. It embodies several trends of the U.S. way of war - namely:
- Fight with materiel rather than manpower whenever possible
- Fight from a distance whenever possible
- Fight as lethally as possible
does all three. In 1979
, a requirement was issued for a comprehensive series of upgrades to the U.S. Army self-propelled gun, the M109. The M109 was designed in the 1950s in response to the needs of the Cold War
Central Front and the Korean Conflict; while it did perform the bare necessities of being self-mobile and minimally protected, there were no allowances in its design for modern computers, communication, environmental protection, or navigation systems. The Paladin
upgrade (designated the A6 model of the M109) set out to fix all that.
The A6 was built from 'reprocessed' M109 units; i.e. older guns were stripped down and major systems salvaged. The original design was little more than a tracked, motorized chassis with a 155mm howitzer mounted atop it. The gun and driving position were enclosed in light armor to protect the crew from small-arms fire, counterbattery shrapnel, and machine guns.
The A6 added a host of improvements. Notably, the gun was spruced up in the hope that it would be better able to survive a 'modern' battlefield. Major systems upgrades included:
...and numerous other, smaller improvements. As of 1999, there were 824 Paladin
s delivered to the U.S. Army
and U.S. Army National Guard
The GPS/LORAN systems allow the Paladin to accurately determine its own position - the first step to being able to accurately aim and fire a ballistic weapon such as the M284 155mm cannon it carries. In addition, the digital communications links allow fire mission orders to be transmitted directly to the automatic fire control and navigation systems. In essence, this means that fire missions can be sent straight to the computer, which can simultaneously instruct the driver where to position the vehicle for an unobstructed fire path, and when the vehicle has been halted, the fire control system automatically unlocks the cannon from travel stowage, slews and raises the barrel to the appropriate deflection and angle, and indicates its readiness to fire. The crew inside the Paladin can fire the first round within 60 seconds of halting the vehicle, and can fire 4 rounds per minute following that up to ranges of approximately 30 kilometers.
Equally important, as soon as the fire mission is complete, the gun can be ready for displace within 15 seconds. This allows fire missions to be completed and the gun to move to avoid any potential return fire, increasing survivability.
There have been proposed follow-on systems to the Paladin, such as the XM2001 SPH Crusader Future Artillery System (don't you love the oh-so-descriptive name?) but the Paladin looks to be relatively secure in its job. More exotic systems such as modular artillery charges, laser ignitors, liquid propellant and automatic resupply vehicles (all part of the now-defunct Crusader follow-on) will have to wait until the Paladin offers a more pressing reason to build an entirely new system.
Paladins are usually deployed in a battery of four guns. While remaining in proximity to each other to ensure that they can concentrate their fire, the guns do not travel together, which complicates the task of anyone trying to shoot back at them. They are serviced and accompanied by several M992 FAASV (Field Artillery Ammunition Servicing Vehicles), which are essentially M109 chassis without cannons. Instead, the turret is modified to store 93 155mm rounds and 99 charges of propellant, and this ammunition is delivered to the M109A6 guns by backing the FAASV up to the gun vehicles and passing ammunition across using either a crane or conveyor.
Some specs, courtesy of the Federation of American Scientists, the U.S. Army and the various manufacturers:
- Length: 9.6 meters approx. with armament (cannon)
- Width: 3.1 meters
- Height: 3 meters (with cannon in travel position)
- Ground Clearance: 18 inches
- Weight: 62,000 lbs (32 tons)
- Max. Speed: 35 MPH
- Cruising range: 186 miles
- Fuel Capacity: 133 gallons
- Crew: Four, including driver
- NBC Protection: Overpressure air conditioning
- Fragment protection: Kevlar spall shielding nets
- Ammunition: 155mm shells, stored in rear of turret bustle with blow-out paneling
- Armament: M284 155mm cannon and M2 50-caliber machine gun mounted at commander's hatch
One of Jane's Fighting Nodes!