The Skywarrior is one of only two U.S. Navy attack aircraft intended as a strategic bomber to enter full-scale service, the other being its predecessor, the North American AJ Savage. The carrier-based supersonic North American A-5 Vigilante was also originally designed for strategic nuclear strike missions and initially, very briefly, supplanted the A-3 in that role beginning in the early 1960s. A modified derivative of the Skywarrior, the B-66 Destroyer, served in the United States Air Force, where it was operated as a tactical bomber, electronic warfare aircraft, and aerial reconnaissance platform up until its withdrawal during the 1970s.