The Boeing X-46 was a proposed unmanned combat air vehicle (UCAV) that was to be developed in conjunction with the United States Navy and DARPA as a naval carrier-based variant of the Boeing X-45 UCAV being developed for the U.S. Air Force. Two contracts for technology demonstrators were awarded in June 2000, to Boeing for the X-46A and to Northrop Grumman for the X-47A.