The 439th Airlift Wing is an active United States Air Force Reserve unit. It is assigned to the Air Force Reserve Command, Fourth Air Force, and is based at Westover Air Reserve Base, Massachusetts.

The Air Force Reserve Command (AFRC) is a major command (MAJCOM) of the United States Air Force, with its headquarters at Robins Air Force Base, Georgia. It is the federal Air Reserve Component (ARC) of the U.S. Air Force, consisting of commissioned officers and enlisted airmen. Together, the Air Force Reserve and the Air National Guard constitute the Air Force element of the reserve components of the United States Armed Forces. AFRC also plays an integral role in the day-to-day Air Force mission and is not strictly a force held in reserve for possible war or contingency operations. AFRC also supports the United States Space Force through the 310th Space Wing, pending the creation of a space reserve component.