The Skyraider was designed during World War II to meet United States Navy requirements for a carrier-based, single-seat, long-range, high performance dive/torpedo bomber that remained in service into the jet age. It was operated by the United States Navy, the United States Marine Corps, and the United States Air Force. It also saw service with the British Royal Navy, the French Air Force, the Republic of Vietnam Air Force and others. It remained in U.S. service until the early 1970s. The AD-6 was an improved AD-4B with improved low-level bombing equipment.