In September 1943 No. 21 Squadron was re-formed at Gawler, South Australia, and re-equipped with Vultee Vengeance dive-bombers. In November the unit moved to Lowood, Queensland, for advanced training. In January and February 1944 the squadron transferred to Nadzab in New Guinea to undertake operations. By the end of February the unit had commenced attacks on Japanese barge hide-outs on the Wagol River. Supply dumps and concentrations of troops were also attacked and the squadron took part in large air raids on the Japanese airstrips at Hansa Bay, Madang and Alexishafen in concert with Nos. 23 and 24 Squadrons.