The Grumman A-6 Intruder was designed as the replacement of the A-1 Skyraider.It's the first all-weather attack aircraft of the US Navy.The aircraft were called as the A2F before 1962 and got the new name,the A-6 Intruder,in service.The outstanding all-weather capability soon made the A-6 the main strike force of the Navy and Marines,and devoted into the Vietnam War. The A-6A were equipped with the DIANE system,which the most advanced navigation / targeting system at that time.But the problems of the reliability were solved after few years.There are 480 A-6As were built and 47of them were upgrade to other type.