Douglas C-118 Liftmaster airplane model. The Douglas DC-6 is an aircraft built by the Douglas Aircraft Company from 1946 to 1959. Originally intended as a military transport near the end of World War II, it was reworked after the war to compete with the Lockheed Constellation in the long-range piston transport market. More than 700 were built, and many still fly today in cargo, military, and wildfire control roles.
The DC-6 was known as the C-118 Liftmaster in United States Air Force service, and as the R6D in United States Navy service.