He led the Salamaua Raid, the first offensive land action against the Japanese in World War II, on 29 June 1942, in which at least 100 Japanese soldiers were killed; the raid also captured Japanese equipment and documents. Described as a copybook action for its diligent scouting, meticulous planning and audacious, Winning, then a captain, led multi-pronged attack against a Japanese force 10 times the attackers' strength. The 2/5th returned to Australia in May 1943 for additional training, and in November Winning transferred to the 2/4th Commando Squadron as second-in-command. The unit deployed near Finschhafen, in New Guinea, for operations against the Japanese on the Huon Peninsula. After a brief trip to Australia in February 1944, he was sent to the Far Eastern Liaison Office in April; on 8 July he was promoted to major and given command of the &lt;a href="2/8th%20Commando%20Squadron%20%28Australia%29"&gt;2/8th Commando Squadron&lt;/a&gt;. They trained at Lae in New Guinea before deploying to Bougainville. The unit engaged the Japanese several times near the Jaba River and in the area north of the Buin Road. Following the war, he left the army on 26 September 1945, and was appointed a Member of the Order of the British Empire in 1947 for his services in Bougainville.