C54

The C-54 Skymaster is the United States military designation for the DC-4 civilian airliner that was adapted for wartime and postwar transport roles. Built by Douglas Aircraft Corporation, the C-54 is a four-engine, piston-powered transport aircraft with a conventional tail and tricycle landing gear. It first entered service with the United States Army Air Forces in 1942 and remained in service with various air forces through the 1950s, often operated by air transport commands.

In its service career, the C-54 played a crucial role during and after World War II. It was a key asset in the Berlin Airlift of 1948-49, delivering food, fuel, and medical supplies to West Berlin. It also served in cargo, troop, and medical-evacuation roles across Europe, the Pacific, and other theaters, supporting both military operations and civilian relief efforts. The aircraft spawned several variants, including C-54A, C-54B, and C-54D, and the United States Navy designated the type as R5D-1. Civil operators inherited many aircraft, keeping them in service into the early jet era.

The C-54 was gradually superseded by larger transports such as the C-124 Globemaster II and later by jet-powered airlift aircraft. It is notable for expanding allied airlift capability during and after World War II. The designation C-54 may also appear in other contexts, but in aviation it most commonly refers to the Skymaster family.