An electical engineer from Sydney, Taplin enlisted in the Australian Army Engineers in 1914. Transferring to the Australian Flying Corps, he was posted to Palestine in 1917, serving with 67 Squadron as a reconnaissance pilot. In July 1918, he joined 4 Squadron in France as a Sopwith Camel pilot. Nine days after he scored his first victory, Taplin was very nearly killed in a flying accident on 26 July 1918. That day, his bomb ladened Camel crashed during take off and he was blown clear, unhurt. On 5 September 1918, Taplin's flight of four Camels was overwhelmed and shot down by Fokker D.VIIs of Jasta 26 and 27. Badly wounded, he scored his final victory and was the only Allied pilot to survive the dogfight. Shot down by Christian Mesch, Taplin was captured and remained a prisoner until the end of the war.