Eighteenth Air Force is a Numbered Air Force in Air Mobility Command (AMC). It serves as the warfighting component of AMC. To accomplish this role, Eighteenth Air Force absorbed the units previously assigned to both Fifteenth Air Force and Twenty-First Air Force, AMC's Tanker/Airlift Control Centre, and two new Expeditionary Mobility Task Forces (EMTFs). The Eighteenth Air Force commander is also the Commander, Task Force 294 (TF 294), which provides aerial refueling to aircraft assigned to the United States Strategic Command (USSTRATCOM) in time of war. TF 294 includes air refueling units from the 18 AF, the Air National Guard, and the Air Force Reserve Command. The United States Air Force created the Eighteenth Air Force to serve as an intermediate echelon of command for extensive troop carrier operations within Tactical Air Command in March 1951. Later, the Eighteenth AF received other combat units in addition to troop carrier wings. On January 1, 1958 Eighteenth Air Force was deactivated and Twelfth Air Force absorbed all of its resources. On October 1, 2003 Eighteenth Air Force was reactivated at Scott Air Force Base.