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.
RAF personnel not wearing No 5 dress, such as airmen, junior officer cadets, and some non-regular officers, wear No 1 dress with the blue shirt and tie swapped for a white shirt (not Marcella) and black bow tie if mess dress is required.