MUROC ARMY AIRFIELD, Calif -- Control of Muroc Army Air Field passed from the Fourth Air Force to the Air Technical Service Command. This effectively combined the Muroc Army Air Field, South Base with Muroc Flight Test Base, North Base. At the same time, the 421st Army Air Forces Base Unit redesignated as the 4144th Army Air Force Base Unit. Colonel Warren E. Maxwell assumed command of the combined facility.
The US Army Air Forces, in addition to its combat units and flying units, also had non-flying units and organizations which used several types of designations during the period of the Army Air Forces, June, 1941 into September, 1947. In addition, the Army Air Forces restructured its domestic and continental structure during early spring 1944, this resulted in a base unit structure. The base units centralized the command of the support functions at a location and created a communication and organizational relations among flying and non-flying elements. It established a logistics basis for air operations. This restructuring resulted from a February 1944 Army Air Forces Headquarters order that units at each installation to be consolidated into Army Air Forces base units. The base unit structure in turn was replaced by base Wing structure in which commanders controlled both facilities and organizations. This arrangement soon lead to the Wing structure used today by the USAF that eliminated the Group level.
Base unit numbering in 1944 -1945 World War II era followed a structure based on the Army Air Force Organization. This structure included allocations for Headquarters, the continental numbered air forces; the major commands; and other non-flying organizations. Because the Air Transport Command had overseas bases. the Air Transport Command structure includes designations for worldwide base units, outside the continental United States in addition to domestic bases. In the base unit numbering, the number of digits and the leading numerals had structural significance. Thus a two digit number reflected certain types of organizations; and similarly, three and four digit numbers represented other organizational structures.