Douglas A4D-1 Skyhawk, U.S. Navy. Designed by Ed Heinemann as a compact, lightweight carrier-based attack jet, the Skyhawk (later re-designated A-4) entered fleet service in 1956 and went on to serve for decades in Navy and Marine Corps squadrons. This early production aircraft, shown in bare-metal finish during a test or evaluation flight, reflects the aircraft's original A4D-1 designation prior to the 1962 tri-service redesignation system. Project: 218475