As Europe and Asia became embroiled in war in the late 1930s, Army Air Force and airline representatives began to plan an air transportation system in the event America became involved in a global war. On 29 May 1941, the Air Corps created the Ferry Command to fly aircraft from U.S. factories to Canada and to Atlantic ports for delivery to Great Britain. When the Japanese attacked on Pearl Harbor on 7 December 1941, the Ferry Command had already delivered over 1300 aircraft to Britain

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On 20 June 1942, The Ferry Command became the Air Transport Command (ATC) with world-wide responsibility for ferrying aircraft; transporting personnel, materiel, and mail; and for maintaining air route facilities.
When the Flying Tigers were disbanded in July 1942, the ATC absorbed their air transport system, China National Airline Corporation.

The ATC used many different types of aircraft including the B-17 Fortress and the B-24 Liberator; its workhorses were the Douglass C-47 Gooney Bird, C-54 Skymaster, and the Curtiss C-46 Commando.

On 1 June, 1948, the newly created United States Air Force formed the Military Air Transport Service (MATS) which absorbed both Air Transport Command and the Naval Air Transport Service.

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