21C7 Aberdeen Commonwealth entered traffic in June 1942 liveried in Wartime Black, despite having been built in Malachite Green. Named at a ceremony on 30 July, 1942, 21C7 took part in smoke clearance trials during 1944 prior to receiving the standard deflectors during May 1947. Malachite Green was restored to 21C7 in July 1947, but less than three years later Aberdeen Commonwealth had received the experimental BR Steam Blue.