Like many other aircraft built during the 1940ís, the Douglas DC-6 was intended for military service yet found its way into airliner service. The DC-6 was Douglasí next step in the evolution of their DC line of aircraft after the widely popular DC-4.
One issue that the military had with the DC-4 was that it was not pressurized. In 1944 the U.S. Army Air Corps issued a request for an expanded and pressurized version of the C-54 Skymaster with improved engines. Douglas went to the drawing board and eventually presented the DC-6. Named the C-118 Liftmaster in the U.S. Air Force, the DC-6 was built as a pressurized, four piston-powered engine-driven transport plane. The DC-6 took its first flight on February 15, 1946 and was everything the Air Force wanted. Unfortunately, by the time Douglas had created the aircraft, the war was winding down to an end and the Air Force no longer wanted the DC-6. Douglas didnít worry though. The DC-6 was easily converted from a military craft into a civilian transport and was introduced to airlines in March of 1947.