Just thought of this. You have to know this to get through BMT: The USAF Organizational Structure.

1 Headquarters United States Air Force
2 Direct Reporting Unit
3 Field Operating Agency
4 Separate Operating Agency
5 Major Command
6 Numbered Air Force
7 Operational Command
8 Air Division
9 Wing
10 Group
11 Squadron
12 Flight
13 Reserve components and auxiliary
When I was in all we had to know were the ones in red text. It was easy to remember with this pneumonic:
How.......HQ USAF
Many......Major Command
New.......Numbered Air Force
Airmen....Air Division
Will........Wing
Get........Group
Sore.......Squadron
Feet.......Flight (The Flight is the smallest element in the Air Force, but can actually have 100 people in it. Typically, Security Forces units are broken down into Flights [sort of like "shifts" or teams] and have alphabetic designations such as Alpha Flight, Beta Flight, Charlie Flight...)

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