The AU-1 was a variant of the F4U Corsair developed from the F4U-5, and was originally designated as the F4U-6 but was renamed to AU-1. It was designed as a dedicated ground attack aircraft, unlike all the previous Corsairs which were designed as fighters. To fit that role the engine was optimized for low-altitude flight, additional armour was fitted, and the AU-1 had increased suspended armament capacity. The United States Marine Corps utilized the AU-1 in Korea starting in 1952, saw service in the Naval reserves from 1954 to early 1956 before it was officially retired in 1957.

Introduced during Update 1.97 "Viking Fury" as a reward for the 2020 "Space Race" event, the AU-1 is like a souped-up version of the Corsair for ground attack enthusiasts. It can carry a much larger payload than the typical Corsair due to additional pylons that can be installed under the airframe and wings. The AU-1 can still be used as a fighter in opportunistic moments against the enemy if they are distracted, but the overall weight penalty from the modifications make the AU-1 poor for dogfights.