A-6 Intruder: Meet the World's First All-Weather Attack Warplane
Initially, the A-6 Intruder was meant to directly replace the Douglas A-1 Skyraider – but the A-1 managed to stay in service a little longer, overlapping with the A-6 for ten years until 1973 – at which point the World War II-designed A-1 was a dinosaur.
Source: nationalinterest.org