The Army Air Forces Air Transport Command

Over the course of World War II the United States Army Air Forces built up what amounted to the largest airline in the world. Through the Air Transport Command and the Naval Air Transport Service, the American military operated a global network of air routes that dwarfed any prewar commercial carrier.

At its height the organization employed tens of thousands of pilots flying many thousands of transport aircraft over routes that spanned every continent and ocean, logging tens of millions of miles. The mainstays of the fleet were rugged workhorses such as the Douglas C-47 Skytrain and the larger four-engine Douglas C-54 Skymaster.

This vast logistics operation, which included the famous airlift over the Himalayan "Hump" to supply China, proved that cargo and personnel could be moved reliably by air on a worldwide scale. The experience, aircraft, and trained crews it produced laid the foundation for the explosive growth of postwar commercial aviation.