The Army has just finished its 10th winter in Afghanistan, a country in which mountainous terrain often means that the only practical method of providing indirect fire support is the mortar. In addition to being easily portable, emplaced, and fired, mortars can be fired with high-arcing trajectories that are invaluable during assaults on insurgents in the mountains. The mortar’s only drawback is its relative lack of accuracy, but that has now changed.
As DOD’s premier test center for artillery and mortars, U.S. Army Yuma Proving Ground (YPG), AZ, is at the forefront in developing guided artillery and mortar projectiles. The technology has evolved to such a degree that it is now in advanced mortar testing with the Accelerated Precision Mortar Initiative (APMI). The program was accelerated, with the competition phase completed in 2010 and acceptance testing concluded early this year. The weapon was fielded in March.
“This will give maneuver commanders, for the very first time, a precision-guided mortar to use at their discretion,” said LTC Norman Hilton, Product Manager Guided Precision Munitions and Mortar Systems. “It gives us the ability to pinpoint precision fire and engage the enemy in situations that cannot be done now. Having an indirect fire weapon with the range and accuracy of this round is a valuable capability.”
[quote align=”left”]It gives us the ability to pinpoint precision fire and engage the enemy in situations that cannot be done now. Having an indirect fire weapon with the range and accuracy of this round is a valuable capability.[/quote]Hard-to-traverse mountain terrain and a rapidly moving enemy are good candidates for the mortar as a weapon of choice. Though well-suited for firing at steep angles, conventional mortars lack the degree of accuracy that allows forces to use them in populated areas or simultaneous to an infantry attack, a fact that APMI hopes to improve.
“A typical mortar can land anywhere within 100 meters of a target,” said Arturo Anaya, Test Officer at YPG’s Munitions and Weapons Division. “The goal is to get this guided round within 10 meters of the target, circular error probable.”
A Recent Test
The test’s objective is to hit a target more than 2½ miles downrange. The gun position is hosting about a dozen additional testers and observers from Program Executive Office Ammunition and Alliant Techsystems Inc., the manufacturer of the guided round. While a typical mortar test is observed with one radar tracker and one high-speed camera, the APMI firing uses two radar trackers and three high-speed cameras at the gun, as well as two high-speed cameras and a television camera at the impact site. The round is tracked in mid-flight by telemetry and a Kineto Tracking Mount, a massive optical tracking system.
Before firing, testers enter the coordinates of the firing and target locations into the Global Positioning System on the 120mm projectile. To eliminate any chance of a catastrophic injury to personnel, a lanyard is attached to a three-sided plate into which the projectile’s muzzle fits. The plate allows the projectile to be suspended over the bipod-braced tube without falling, and is pulled free by the lanyard when all personnel are behind the reinforced concrete bombproof structure.
[quote align=”left”]A typical mortar can land anywhere within 100 meters of a target. The goal is to get this guided round within 10 meters of the target, circular error probable.[/quote]More to Come
The successful test for accuracy is far from the only one to which the guided projectile was subjected before being fielded to troops. There were safety tests that measured the round’s ability to endure the expected logistical and tactical transportation, storage, and handling environments, such as being moved over rough terrain, as well as various tests that simulated accidental drops from a transport vehicle or while the projectile is being dropped into a mortar tube. All of these tests were performed to demonstrate performance, safety, and reliability.
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- MARK SCHAUER is a Public Affairs Specialist at YPG. He holds a B.A. in history from Northern Arizona University where he is also pursuing an M.A. in English.
