A Master Sergeant is the seventh enlisted rank in the United States Air Force, just above
Technical Sergeant and below
Senior Master Sergeant. It is abbreviated as "MSgt." Advancement to Master Sergeant is one of the most significant promotions within the enlisted Air Force. At the rank of Master Sergeant, the airman enters the senior noncommissioned tier and his or her duties begin to focus on leadership and management rather than technical performance. Per Air Force Instruction 36-2118, MSgts typically serve as flight chiefs (analogous to platoon sergeants in the US Army) and section chiefs (leaders of duty sections within a squadron).
It is also the lowest rank in the Air Force that one can hold in order to attain the special duty position of
Master Sergeant / First Sergeant. These First Sergeants (pay grades E-7 to E-9) are referred to officially as "First Sergeant" (regardless of their pay grade), and unofficially as "First Shirt" or simply the "Shirt".
