A Delta DC-4 flew the world's first nonstop scheduled flight between Chicago and Miami on November 1, 1946.
Eastern Airlines met Delta's challenge on the Chicago-Miami run with pressurized Lockheed Constellations, allowing smoother flights avoiding more bad weather, to counter Delta's unpressurized DC-4s. In 1948, Delta put the pressurized DC-6 into service.
"For the first time that we had on the airline, an airplane that we didn't have to worry about fuel. We always had enough fuel on that DC-4 to go 2,000 miles, and somewhere in the United States, the weather was satisfactory for a let down within 2000 miles. So fuel was no problem…The DC-4 was very dependable airplane, had very dependable engines, had adequate anti-icing." Fritz Schwaemmle, hired as a Delta pilot in 1934.
The DC-4 had a simple autopilot system that provided altitude and directional hold.
The DC-4 was Delta's first aircraft that was not a "tail-dragger." Because the cabin was level when the DC-4 was on the ground, it was easier to board and exit than earlier Delta aircraft.
Chief Engineer J. F. Nycum designed the galley for Delta's DC-4 aircraft, which were reconverted military C-54B Skymasters. Douglas Aircraft Company made Delta's galley the standard for all DC-4s coming off its modification line.