Air Division (United States)
In the United States Air Force, a division was an intermediate level of command, subordinate to a numbered air force, controlling one or more wings. It also controlled squadrons without associated same-function wings, i.e., 17th Defense Systems Evaluation Squadron had no associated wing, but its function was part of the 24th Air Division.
Source: Wikipedia — Air Division (United States) (CC BY-SA 4.0)