1919, Air Ministry Order 1049 replaced it with the blue-grey colour which has remained in use to this day. The khaki uniform continued to be worn until 1924 when it too was replaced by a blue-grey colour. War service dress War service dress, also known as battle dress, was introduced in 1940 as a blue/grey version of the British Army's battle dress. Initially, war service dress was only worn by air crew. However, in 1943, its use was authorised for all ranks and trades. War service dress continued to be worn after the end of World War II. It was significantly altered in 1948 and not phased out until 1976. Later changes in service dress Air force rumour later had it that the "air force blue" colour of the postwar uniform had been that of a textile produced in quantity to clothe Russian soldiers during the First World War, and not yet exported when the Russian revolution of 1917 closed that market. A visible distinction between the RAF and the other military services was that all ranks wore a starched collar and tie. Up to 1918, only Officers of the British Army and Royal Navy wore neck-ties; and Officers of all services bought their uniforms from military tailors, while other servicemen were issued clothing from government stocks. Several features of the RAF uniform distinguished officers from airmen; their cap badges were different, airmen's being all brass while officers' were gold-embroidered fabric; airmen wore the RAF eagle patch on both shoulders while officers did not; and the fabric of airmen's wool uniforms was thick and heavy, while officers' uniforms were of "smooth blue" barathea fabric. Another distinction was that while the British Army shod its men only in ankle-high boots the RAF after 1945 also issued its airmen with ordinary shoes for everyday working wear. The shoes maintained the class distinction in that only officers wore shoes with toecaps. Similarly, officers wore unlined brown leather gloves while airmen's gloves were of knitted wool. "Smooth blue" uniforms for non-commissioned personnel were introduced in the 1950s, first for Warrant Officers. By 1956 NCOs of all ranks (corporal and up) were permitted to buy "smooth blue" uniforms at their own expense. Another innovation of the period was raincoats, hitherto worn only by officers. Despite the rainy British climate, the only weather protection for airmen outdoors was either their heavy winter overcoats or the rectangular