The squadron deployed to the front lines of the New Guinea Campaign during July 1942. Its advance party left Townsville for its new base at Milne Bay early in the month, and the fighters departed on 19 July. No. 76 Squadron flew its first combat mission on 22 July when its new commanding officer, Squadron Leader Peter Turnbull, led a force of six Kittyhawks from Port Moresby to attack Japanese positions near Gona. No. 75 Squadron also arrived at Milne Bay on 31 July. Conditions at Milne Bay were extremely difficult as the squadron's airfield was not finished, living and maintenance facilities were almost non-existent and high rainfall meant that any aircraft which ran off the runways and taxiways became bogged in mud. No. 76 Squadron aircraft intercepted Japanese raids on Milne Bay on 4 and 11 August.