The deal, which includes airborne electronics and ground support equipment, is for three AQS-24A airborne mine hunting systems and marks the culmination of a 2011 deal that will allow some components to be made in Japan.
"These additional contracts further strengthen our relationship with the JMSDF," said Tom Jones, vice president of Northrop Grumman's Undersea Systems business unit.
The AQS-24As to be supplied are primarily towed from the MH-53E helicopter but have been adapted for aircraft flown by Japan.
The AQS-24A system's high-resolution side-scan sonar detects, localizes and classifies bottom and moored mines in real time. It also features a laser line scanner. Both can be used simultaneously.
"The AQS-24A allows for simultaneous operation of the sonar and laser, which significantly improves area coverage rate, shortens the mine clearance timeline and alleviates unnecessary maintenance cycles," Northrop Grumman said. "Advanced navigation controls and processing provide highly accurate target positioning."
The monetary value of the order was not disclosed.