United States Air Force enlisted rank insignia

The chart below represents the current enlisted rank insignia of the United States Air Force.

While all Air Force military personnel are referred to as Airmen, it can specifically refer to the pay grades of E-1 through E-4 which are below the level of non-commissioned officers (NCOs). Above the pay grade of E-4 (E-5 through E-9) all ranks fall into the category of NCO and are further subdivided into NCOs (E-5 & E-6) and Senior NCOs (E-7 through E-9); the term Junior NCO is sometimes used to refer to staff sergeants and technical sergeants (E-5 & E-6).

The Air Force is the only one of the five branches of the United States military where NCO status is now only achieved at the grade of E-5. Formally, the grade of Sergeant was obtained after a time as a Senior Airman and successful completion of the Air Force NCO School. In all other branches NCO status can be achieved at the grade of E-4 (a Corporal in the Army and Marine Corps, Petty Officer Third Class in the Navy and Coast Guard). However, E-4s in the Army with the rank of Specialist are not NCOs. The Air Force mirrored the Army from 1976 to 2 May 1991 with an E-4 being either a Senior Airman wearing three stripes without a star or a Sergeant (informally referred to as "Buck Sergeant") which was noted by the presence of the central star and considered an NCO. Despite not being an NCO, a Senior Airman who has completed Airman Leadership School can be a supervisor.

Although the Air Force became an independent service with the National Security Act of 1947, it retained the Army Air Force rank structure and corresponding insignia of years past. This rank structure provided for seven enlisted ranks: Private, Private First Class, Corporal/Technician Fifth Grade, Sergeant/Technician Fourth Grade, Staff Sergeant/Technician Third Grade, Technical Sergeant and Master Sergeant/First Sergeant. Additionally, Air Force personnel were still referred to as soldiers. During the Second World War, many USAAF NCOs wore the Army Air Corps branch insignia of the winged propeller underneath their chevrons.

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