The Douglas DC-6 was one of the first airplanes to fly a regularly scheduled around-the-world route. With its higher performance, increased accommodation, greater payload and pressurized cabin, it was a natural evolution of the DC-4.

Although the DC-6 had the same wingspan as the DC-4, its engines helped it fly 90 mph (145 kph) faster than the DC-4, carry 3,000 pounds (1350 kilograms) more payload and fly 850 miles (1368 kilometers) farther. The DC-6 could maintain the cabin pressure of 5,000 feet (1524 kilometers) while flying at 20,000 feet (6096 meters).

The larger, all-cargo DC-6A first flew Sept. 29, 1949; the larger capacity DC-6B, which could seat up 102 people, first flew Feb. 10, 1951.