The Phalanx CIWS will be installed on Australia's newest Air Warfare Destroyer, the Brisbane, which is under construction.
"The Phalanx CIWS includes a fast-reaction 20mm Gatling gun that will provide the destroyers with a line of defense against anti-ship missiles, littoral or close-to-shore warfare threats and aircraft at short range," said Rod Equid, chief executive officer of Australia's AWD alliance said.
"The AWD Phalanx CIWS, the Mk15 Block 1B, is integrated into the Aegis Weapon System and is an updated version of the equipment already in use by the Royal Australian Navy on the Adelaide class guided-missile frigates."
The AWD alliance, which is procuring three U.S.-made Phalanx systems through Raytheon Australia is made up of the government's Defense Materiel Organization, shipbuilder ASC and Raytheon Australia, the mission systems integrator.
The Phalanx Mk15 Block 1B can fire as many as 4,500 rounds a minute and includes search-and-track radars with an integrated electro-optic sensor.
Raytheon delivered the first of three systems -- for the Hobart -- in last year and the final system is under construction.
"These Phalanx systems will give the Royal Australian Navy the most advanced ship self-defense capability available worldwide," said Rick Nelson, vice president of Raytheon Missile Systems' Naval and Area Mission Defense product line. "Thanks to recent engineering changes, we have improved the system's reliability, added capability and greatly improved the sailor-to-machine interface in order to defeat extended-range air and surface threats."