[1][2] The lack of uniform insignia for airman basic is the reason for the nickname "slick-sleeve"; all other enlisted Air Force ranks wear stripes and chevrons on their uniform sleeves.
On April 24, 1952, Air Force Regulation 39-36 was published, changing the name of the lowest enlisted U.S. Air Force rank to "basic airman"—whose holders still bore no insignia—immediately below the new "airman third class".
[5] On February 5, 1959, the new Air Force regulation governing the titles of enlisted ranks was released; the only change being direction that the title for E-1 was changed from "basic airman" to "airman basic".
[5] Under normal circumstances, airmen basic are eligible for promotion to airman (E-2) after six months' time in grade (TIG).
However, individuals enlisting for six years are promoted from AB to airman first class (A1C) upon completion of either technical training (or 20 weeks thereof) or the indoctrination course for combat control or pararescue.