What is the difference between a master sergeant, senior master sergeant, and chief master sergeant in the United States Air Force (USAF)? - Quora
Appendix I: Acronyms and Abbreviations | Strengthening U.S. Air Force Human Capital Management: A Flight Plan for 2020-2030 | The National Academies Press
![United States Military Rank Structure for the Air Force, Army, Marines, Navy, National Guard and Coast Guard Insignia - Military Rank United States Military Rank Structure for the Air Force, Army, Marines, Navy, National Guard and Coast Guard Insignia - Military Rank](https://www.aviationexplorer.com/PAY_GRADE_NCO_INSIGNIA.jpg)