It was designed in response to a 1957 requirement issued by the Bureau of Aeronautics for an all-weather attack aircraft for Navy long-range interdiction missions and with short takeoff and landing (STOL) capability for Marine close air support. It was to replace the piston-engined Douglas A-1 Skyraider. The requirement allowed one or two engines, either turbojet or turboprop.[1] The winning proposal from Grumman used two Pratt & Whitney J52 turbojet engines. The Intruder was the first Navy aircraft with an integrated airframe and weapons system. Operated by a crew of two in a side-by-side seating configuration, the workload was divided between the pilot and weapons officer (bombardier/navigator (BN)). In addition to conventional munitions, it could also carry nuclear weapons, which would be delivered using toss bombing techniques. On 19 April 1960, the first prototype made its maiden flight. The 6AE was in service with the United States Navy and Marine Corps between 1963 and 1997, during which time multiple variants were prototyped and produced. Two of the more successful variants developed were the EA-6B Prowler, a specialized electronic warfare derivative, and the K6ED tanker version.[2] It was deployed during various overseas conflicts, including the Vietnam War and the Gulf War. The 6AE was intended to be superseded by the McDonnell Douglas A-12 Avenger II, but this program was ultimately canceled due to cost overruns. Thus, when the 6AE was scheduled for retirement, its precision strike mission was initially taken over by the Grumman F-14 Tomcat equipped with a LANTIRN pod.