Based
on the success of the Douglas DC-4/C-54, the U.S. Army Air Force
requested Douglas to develop a larger capacity aircraft. The
prototype XC-112 first flew on 15 February 1946, too late for
participation in the war.
Douglas developed this design for postwar airline
service as the DC-6 making its initial flight with American
Airlines in June 1946.
Civil DC-6s were built alongside 166 aircraft for
the U.S Air Force and Navy designated the C-118 and R6D
Liftmaster respectively. One C-118 was given a VIP
interior for President Truman and designated the VC-118 The
Independence. Other VC-118s also served as Air Force One.
A total of 704 civil and military DC-6s were
built.