Northrop delivers sonar upgrade kits to U.S. Navy
September 22, 2016 at 13:40 PM EDT
Richard Tomkins ANNAPOLIS, Md., Sept. 22 (UPI) -- The first of three lots of mine-hunting AQS-24B sonar upgrade kits have been delivered by Northrop Grumman to the U.S. Navy's Naval Surface Warfare Center.