PATUXENT RIVER NAS, Md. - Aerial target experts at Orbital Sciences Corp. in Chandler, Ariz., are building additional supersonic target drones for the U.S. Navy and allies to help surface warship crews practice how to detect and defeat incoming supersonic anti-ship missiles.Officials of the Naval Air Systems Command at Patuxent River Naval Air Station, Md., announced a $52.9 million contract to Orbital on Monday to build 18 GQM-163A lot 12 full-rate-production Coyote supersonic sea skimming target base vehicles for the U.S. Navy and governments of Japan and Israel. The French navy also operates the GQM-163A.