WASHINGTON — The US Army has awarded Orbital ATK with a $120 million contract modification to make kits that turn conventional 155mm artillery into a near-precision shell.
The kits are meant to limit civilian casualties and collateral damage, allowing the use of artillery where it would have otherwise been ill-advised — in a congested area or near friendly forces.The guidance fuzes would be fielded to the Army, the Marine Corps, Australia and Canada. Deliveries are scheduled to begin in early 2016, following low-rate initial production, which began in January.
"The goal was to try to design a fuze that would also provide guidance that would just drop into the existing inventory because the Army has millions of rounds," said Tim Jones, PGK program manager for Orbital ATK. "To build new rounds — and there are programs like that — are very expensive, more than 10 times what PGK would cost."
The PGK fuze screws into the fuze well of 155mm high-explosive artillery projectiles. It uses a GPS to determine its position relative to the target and uses small aerodynamic fins to perform in-flight course corrections along its ballistic trajectory.
"Missions were being denied because of collateral damage concerns," Jones said. "The enemy isn't always out in the open, so artillery really had to improve accuracy to stay in the fight to the level the Army wants it to be."
The accuracy of area fire weapons is based on circular error probability (CEP), the imaginary circle around a target within which a round would fall. PGK, according to the company, reduces artillery dispersion of more than 200 meters to less than 30 meters.
Once of the engineering challenges, Jones said, was to miniaturize the fuze and GPS guidance system to fit inside the fuze well, with no other modifications to the 155 rounds. Ultimately, it weighs about three pounds, while the "dumb" fuze weighs two pounds — the difference being the fins and alternator.
The kit includes a "fail-safe" option to keep a round from detonating if it does not get close enough to the target.
According to Jones, the program has performed compatibility testing for international platforms and with countries that use US rounds.
"There's a tremendous amount of overseas interest and the US Army is interested in working with allies," Jones said.
During this demonstration, PGK delivered 90 percent of rounds fired within five meters accuracy of the target positioned 27 kilometers from the gun position.
Joe Gould is senior Pentagon reporter for Defense News, covering the intersection of national security policy, politics and the defense industry.