4.2 The Enlisted Force Structure & Tiers

Key Takeaways

  • The enlisted force structure has three tiers: junior enlisted (AB through SrA), noncommissioned officer (SSgt and TSgt), and senior noncommissioned officer (MSgt, SMSgt, and CMSgt).
  • The 5-skill level is typically earned as an Airman First Class and the 7-skill level as a Staff Sergeant.
  • PME gates are sequential: Senior Airmen must complete Airman Leadership School before assuming SSgt, TSgt must complete the NCO Academy before assuming MSgt, and MSgt must complete the SNCO Academy before assuming SMSgt.
  • Official terms of address differ by grade — a Staff Sergeant may be addressed as 'Staff Sergeant' or 'Sergeant,' a Senior Master Sergeant as 'Senior Master Sergeant,' 'Senior,' or 'Sergeant,' and a Chief Master Sergeant as 'Chief Master Sergeant' or 'Chief.'
  • Junior enlisted Airmen progress through the Airmanship Continuum of 100 (Basic Military Training), 200 (Technical Training), and 300 (First-Term Airmen Center).
Last updated: August 2026

Why the Structure Exists

AFH 1 states the purpose: "To best leverage our resources, we must have a consistent, well-defined set of expectations, standards, and growth opportunities for all Airmen, regardless of rank or specialty." The enlisted force structure provides "the framework to best meet mission requirements while developing foundational and occupational competencies."

It is comprised of three distinct and separate tiers, each correlating to increased levels of education, training, and experience, which build increasing levels of proficiency, leadership, and managerial responsibilities.

Tier 1 — Junior Enlisted

Ranks: Airman Basic, Airman, Airman First Class, Senior Airman.

Initial enlisted accessions enter here and are introduced to the foundational competencies. The tier focuses on adapting to the military, being part of the profession of arms, achieving occupational proficiency, and learning to be productive members of the USAF. Junior enlisted Airmen progress through the Airmanship Continuum of 100 (Basic Military Training), 200 (Technical Training), and 300 (First-Term Airmen Center) — three numbers with three named venues, a classic matching item.

GradeAbbrev.Official term of addressAFH 1 expectations
Airman BasicAB"Airman Basic" or "Airman"Adapting to the military profession, acquiring knowledge of standards, customs, and courtesies; close supervision
AirmanAmn"Airman"Understands and conforms to military standards; begins to show proficiency at basic tasks; requires significant supervision
Airman First ClassA1C"Airman First Class" or "Airman"Fully complies with USAF standards; becoming an effective team member; typically earns the 5-skill level at this grade; continued supervision essential
Senior AirmanSrA"Senior Airman" or "Airman"Performs as skilled technician and trainer; begins developing supervisory and leadership skills; must complete Airman Leadership School before assuming the grade of Staff Sergeant

Tier 2 — Noncommissioned Officer (NCO)

Ranks: Staff Sergeant and Technical Sergeant. Just two grades — an item offering "SSgt through MSgt" for the NCO tier is wrong.

NCOs "continue occupational growth and become expert technicians while developing as leaders, supervisors, managers, and mentors in the profession of arms." They ensure they and their subordinates stay trained, qualified, and ready to deploy and operate at home station and in an expeditionary environment, and pursue professional development including the developmental special duty selection process and PME.

GradeAbbrev.Official term of addressAFH 1 expectations
Staff SergeantSSgt"Staff Sergeant" or "Sergeant"Skilled technician with supervisory and training responsibilities; typically earns the 7-skill level at this rank; ensures proper use of resources under their control
Technical SergeantTSgt"Technical Sergeant," "Tech Sergeant," or "Sergeant"Often the unit's technical expert; must complete the NCO Academy before assuming the grade of Master Sergeant

Note that Technical Sergeant is the only grade with three authorized forms of address, because "Tech Sergeant" is expressly listed.

Tier 3 — Senior Noncommissioned Officer (SNCO)

Ranks: Master Sergeant, Senior Master Sergeant, Chief Master Sergeant.

SNCOs "serve as leaders in the profession of arms," and advise, supervise, mentor, and develop junior enlisted Airmen and NCOs. They participate in decision-making on technical, operational, and organizational issues, and may attend sister service or international SNCO courses.

GradeAbbrev.Official term of addressAFH 1 expectations
Master SergeantMSgt"Master Sergeant" or "Sergeant"Technical expert transitioning from first-line supervisor to leader of operational competence; should consider broadening through the developmental special duty process; must complete the SNCO Academy before assuming the grade of Senior Master Sergeant
Senior Master SergeantSMSgt"Senior Master Sergeant," "Senior," or "Sergeant"Experienced, operational leader, skilled at merging team talents, skills, and resources with other organizations
Chief Master SergeantCMSgt"Chief Master Sergeant" or "Chief"Substantial operational and occupational experience; strategic leadership positions with tremendous influence; mentors junior enlisted and influences the professional development of company grade officers

Chief Leadership Course rule: all newly selected RegAF chiefs will attend the Chief Leadership Course; newly selected Reserve Component chiefs attend either the Chief Leadership Course or their Chief Orientation Course.

The Two Ladders You Must Not Confuse

The PFE routinely mixes the skill-level ladder with the PME ladder because both appear in this one section.

MilestoneGrade at which it typically occurs
5-skill level (Journeyman)Airman First Class
7-skill level (Craftsman)Staff Sergeant
Airman Leadership SchoolRequired of Senior Airman before assuming SSgt
NCO AcademyRequired of TSgt before assuming MSgt
SNCO AcademyRequired of MSgt before assuming SMSgt
Chief Leadership CourseNewly selected CMSgt

Notice the pattern in the PME gates: each is completed in the grade immediately below the one being assumed, and each sits at the top of its tier — ALS at the top of the junior enlisted tier, NCOA at the top of the NCO tier, SNCOA in the middle of the SNCO tier, CLC at the top.

A Note on Address Traps

Three grades may be addressed as "Airman" (AB, Amn, A1C, SrA — four grades, all of the junior enlisted tier). Three grades may be addressed as "Sergeant" (SSgt, TSgt, MSgt, SMSgt — note that Chief Master Sergeant is not addressed as "Sergeant"). Only the Chief Master Sergeant is addressed as "Chief." Items in this area typically offer a plausible-sounding but unauthorized form such as "Master" for MSgt or "Staff" for SSgt.

Test Your Knowledge

At which grade does AFH 1 state the 7-skill level is typically earned, and which PME course must be completed before assuming that grade?

A
B
C
D
Test Your Knowledge

Which grade has three authorized official terms of address listed in AFH 1?

A
B
C
D
Test Your Knowledge

A Master Sergeant is described in AFH 1 as transitioning between which two roles?

A
B
C
D