No. 78 Wing was formed on 24 November 1943 at Townsville, Queensland, under the command of Wing Commander (later Group Captain) W.D. Brookes. Along with No. 77 Wing, it came under the control of No. 10 Operational Group, a mobile strike force supporting the Allied armies as they advanced in the South West Pacific theatre. No. 78 Wing's flying units were originally to have consisted of No. 80 Squadron, operating P-40 Kittyhawk fighters, and Nos. 452 and 457 Squadrons, operating Spitfires. The Spitfire squadrons could not be released from duty in the North-Western Area as planned, and Nos. 75 and 78 Squadrons took their place, making the formation an all-Kittyhawk force. No. 78 Wing flew combat air patrols and ground-attack missions during Operations Reckless and Persecution, the assault on Hollandia and Aitape, New Guinea, in April 1944. By the middle of the year, the wing's flying hours in New Guinea were consistently higher than those of its counterparts in the US Fifth Air Force.