Douglas DC-6 C-118A Liftmaster

The C-118A Liftmaster is the designation of the DC-6As built for the United States Air Force: 101 aircraft, with the same two cargo doors and strengthened floor as the civil freighter. The Air Force and the Navy renewed their interest in the DC-6 during the Korean War and together ordered 167 C-118/R6D aircraft, many of which later found their way to civil airlines.

Two service derivatives came out of the C-118A: the VC-118A, converted as staff transports, and — from the other side of the family — the C-118B, which is simply the Navy's R6D-1 redesignated when the American military nomenclatures were unified. The VC-118B are, likewise, redesignated R6D-1Z aircraft.

The Liftmaster name actually started with the civil DC-6A, but it was the military aircraft that made it stick, just as the C-54 Skymaster had earlier popularised the DC-4's name.