Douglas DC-6

Douglas DC-6
source
Name	Douglas DC-6
Caption	A DC-6B of Western Airlines in 1966
Type	Airliner and transport aircraft
National origin	United States
Manufacturer	Douglas Aircraft Company
First flight	15 February 1946
Introduction	March 1947 with American Airlines
Status	In limited service
Primary user	United States Air Force
Number built	704
Developed from	Douglas DC-4
Developed into	Douglas DC-7

Douglas DC-6. The Douglas DC-6 is a piston-engine airliner and cargo aircraft built by the Douglas Aircraft Company from 1946 to 1958. Originally conceived as a military transport for the United States Army Air Forces at the end of World War II, it was redeveloped for the commercial market to compete with the Lockheed Constellation. Known for its reliability, pressurization, and long range, it became a mainstay for major airlines and military operators worldwide for decades.

Development and design

The development of the aircraft was initiated in 1944 under the designation **XC-112**, intended as a pressurized and more powerful development of the C-54 Skymaster for the United States Army Air Forces. The end of World War II led to the cancellation of the military order, prompting Douglas Aircraft Company to redesign it as a commercial airliner. Key design features included a fully pressurized cabin, allowing for more comfortable flight above weather, and four powerful Pratt & Whitney R-2800 Double Wasp radial engines. The design competed directly with the Lockheed Constellation and was seen as a more robust and maintainable alternative, incorporating lessons from wartime operations of the DC-4. The prototype, designated **DC-6**, first flew from Santa Monica, California in early 1946.

Operational history

The aircraft entered commercial service with American Airlines on its New York to Chicago route in 1947. Its introduction was temporarily marred by a series of in-flight fires, leading to a grounding by the Civil Aeronautics Board until the cause—a fuel vent line near the cabin heater—was identified and rectified. Once returned to service, it proved exceptionally successful, being adopted by major carriers like United Airlines, Pan American World Airways, and Braniff International Airways. It served as a primary transcontinental and transoceanic airliner throughout the 1950s, significantly reducing travel times. Many were also acquired by the United States Air Force as the **C-118 Liftmaster** and by the United States Navy as the **R6D**, serving as a VIP transport, including the famous presidential aircraft "*Independence*" used by Harry S. Truman. Its ruggedness led to a very long service life in cargo and firefighting roles.

Variants

The primary variants included the initial **DC-6** with accommodation for 50 to 68 passengers. The **DC-6A** was a dedicated "liftmaster" cargo model with a strengthened floor, a large forward cargo door, and increased fuel capacity. The **DC-6B** was the definitive passenger version, optimized for longer ranges and typically seating up to 102 passengers in a high-density configuration, with the cargo door omitted. Military versions included the **USAF C-118A** and the **USN R6D-1**, which were essentially DC-6A models. A single **VC-118** was configured as the presidential transport. The **DC-6C** was a convertible cargo-passenger model.

Operators

Major civil operators spanned the globe and included American Airlines, United Airlines, Pan American World Airways, Braniff International Airways, Northwest Orient Airlines, Sabena, and Scandinavian Airlines System. The United States Air Force and United States Navy were the largest military operators. Many were also flown by Air America during the Vietnam War. The aircraft's longevity saw it later used by numerous charter and cargo operators, such as Evergreen International Airlines, well into the 21st century.

Accidents and incidents

The type was involved in several notable accidents. The 1947 grounding was precipitated by a fatal crash of a United Airlines flight near Bryce Canyon, Utah. In 1951, a Cubana de Aviación flight crashed into the Atlantic Ocean after takeoff from Bermuda. A 1963 crash of a Northwest Orient Airlines flight into the Pacific Ocean near Annette Island in Alaska resulted in significant loss of life. Other incidents included a 1960 Capital Airlines crash in Charlottesville, Virginia, and a 1972 Aeroflot crash at Moscow's Sheremetyevo International Airport.

Specifications (DC-6B)

* **Crew:** 3–4 * **Capacity:** 54–102 passengers * **Length:** 105 ft 7 in (32.18 m) * **Wingspan:** 117 ft 6 in (35.81 m) * **Height:** 28 ft 5 in (8.66 m) * **Empty weight:** 55,357 lb (25,110 kg) * **Max takeoff weight:** 107,200 lb (48,600 kg) * **Powerplant:** 4 × Pratt & Whitney R-2800 Double Wasp 18-cylinder air-cooled radial piston engines, 2,500 hp (1,900 kW) each * **Maximum speed:** 358 mph (576 km/h, 311 kn) * **Cruise speed:** 315 mph (507 km/h, 274 kn) * **Range:** 3,983 mi (6,410 km, 3,461 nmi) * **Service ceiling:** 25,000 ft (7,600 m)

Aircraft on display

Several aircraft are preserved in museums. Examples include a former United States Air Force **VC-118** (serial 53-3242) at the National Museum of the United States Air Force at Wright-Patterson Air Force Base in Ohio. A DC-6B formerly operated by Scandinavian Airlines System is displayed at the Danmarks Flymuseum in Stenlille, Denmark. The Museum of Flight in Seattle has a DC-6B cockpit section. A former United States Forest Service firefighting tanker is on display at the Airline History Museum in Kansas City, Missouri.

Category:Aircraft first flown in 1946 Category:United States airliners 1940–1949