 The tartan is worn by the RAF's voluntary pipes bands, although not as part of an official RAF uniform.RAF personnel without No 5 dress, such as airmen, junior officer cadets and some non-regular officers, wear No 1 dress with the blue shirt and tie replaced with a white shirt (not Marcella) and black bow tie should the need to wear mess dress arise.This dress pattern is officially designated Number 4 Dress and was previously known as "(Interim) Mess Dress".