Douglas DC-6

DC-6
Douglas DC-6B of Swiss airline Balair in 1976
Role Airliner/transport aircraft
Manufacturer Douglas Aircraft Company
First flight February 15, 1946
Introduced March 1947
Status 49 fully active
Primary users United States Air Force
United States Navy
Produced 1946-1959
Number built >700
Developed from Douglas DC-4
Variants Douglas DC-7

The Douglas DC-6 is a piston-powered airliner and transport aircraft built by the Douglas Aircraft Company from 1946 to 1958. Originally intended as a military transport near the end of World War II, it was reworked after the war to compete with the Lockheed Constellation in the long-range commercial transport market. More than 700 were built and many still fly today in cargo, military and wildfire control roles.

The DC-6 was known as the C-118 Liftmaster in United States Air Force service and as the R6D in United States Navy service prior to 1962 after which all U.S. Navy variants were also designated as the C-118.

Contents

Design and development

The United States Army Air Forces commissioned the DC-6 project as the XC-112 in 1944. The Air Force wanted an expanded, pressurized version of the popular C-54 Skymaster transport with improved engines. By the time the XC-112 flew the war was over and the USAAF had rescinded its requirement.

Douglas converted its prototype into a civil transport (redesignated YC-112A, having significant differences from subsequent production DC-6 aircraft) and delivered the first production DC-6 in March 1947. However, a series of mysterious in-flight fires (including the fatal crash of United Airlines Flight 608) grounded the DC-6 fleet later that year. The cause was found to be a fuel vent located adjacent to the cabin cooling turbine intake. All DC-6s in service were modified to correct the problem, and the fleet was flying again after just four months on the ground.

Operational history

Passengers deplaning an SAS DC-6. Note the upper row of windows, indicating this was built as the optional sleeper variant of the original length DC-6

Pan Am used DC-6B aircraft to inaugurate its first trans-Atlantic tourist class flights, starting in 1952.

Douglas designed four basic variants of the DC-6: the "basic DC-6," and the longer fuselage, higher-gross-weight, longer range versions—the "DC-6A" with large cargo doors forward and aft of the wing on the port (left hand side) with a cargo floor, the "DC-6B" designed for passenger work, had passenger doors only and a lighter floor and the "DC-6C" a "convertible" aircraft built with the 2 cargo doors, but fitted with removable passenger seats. The DC-6B, originally powered by Pratt & Whitney R-2800-CB-16 engines with Hamilton Standard 43E60 constant speed reversing propellers, was regarded as the ultimate piston-engine airliner from the standpoint of ruggedness, reliability, economical operation and handling qualities. The military version, essentially similar to the DC-6A, was the USAF C-118 Liftmaster, and the USN R6D which used the more powerful R-2800-CB-17 engines. The more powerful engine was later used on the commercial DC-6B to accommodate international flights. The Navy version (in the late 1950s and early 1960s) had Curtiss Electric constant-speed reversing propellers.

The USAF and USN renewed their interest in the DC-6 during the Korean War, and ordered a total of 167 C-118/R6D aircraft, some of which later found their way into civilian service. Harry Truman's first presidential aircraft was an Air Force VC-118 called "The Independence".

Total production of the DC-6 Series was 702 including military versions.

In the 1960s, two DC-6s were used as transmitter platforms for educational television, based at Purdue University, in a program called MPATI (Midwest Program for Airborne Television Instruction).[1]

Many older DC-6 aircraft were replaced in airline passenger service by the Douglas DC-7, but the simpler, more economical engines in the DC-6 has meant that this type has out-lived the more sophisticated DC-7. DC-6/7s surviving into the Jet Age were replaced in front line service by Boeing 707 and Douglas DC-8 aircraft.

2006 marked the 60th anniversary since the introduction of the DC-6.

Variants

UAL DC-6 at Stapleton Airport, Denver, in September 1966
Pan Am DC-6B at London Heathrow in September 1954 on a tourist flight
XC-112
United States military designation of an improved version of the C-54 (DC-4); became the prototype DC-6. Eventually designated YC-112A, pressurized, P&W R-2800-83AM3 engines
DC-6
Initial production variant.
DC-6A
Freighter variant; fuselage slightly lengthened from DC-6 ; fitted with cargo door.
DC-6B
All-passenger variant of DC-6A, without cargo door.
DC-6C
Convertible cargo/passenger variant.
VC-118
One DC-6 bought as a presidential transport with special 25 seat interior and 12 beds.
C-118A
Designation of DC-6As for the United States Air Force, 101 built.
VC-118A
C-118As converted as staff transports.
C-118B
R6D-1s re-designated.
VC-118B
R6D-1Zs re-designated.
R6D-1
United States Navy designation for the DC-6A, 65 built.
R6D-1Z
Four R6D-1s converted as staff transports.

Operators

G-APSA in British Eagle scheme
G-APSA displaying at Hamburg
The Red Bull DC-6B landing at Salzburg
Current operators of the DC-6
Today, most DC-6s have gone, with only a few left flying. Several of these are based in Europe and the United Kingdom. A few other DC-6s are still in operation for small carriers in South America.

Civil operators

 Brazil
 Greece
 Namibia
 Netherlands
 New Zealand
 United Kingdom
 United States

Military operators

 Argentina
 Belgium
 Bolivia
 Brazil
 Chile
 Republic of China (Taiwan)
 Colombia
 Ecuador
 El Salvador
 France
 Germany
 Guatemala
 Honduras
 Italy
 South Korea
 Mexico
 New Zealand
 Peru
 Portugal
 Republic of China
 United States
 South Vietnam
 Yugoslavia
 Zambia

Notable incidents and accidents

Survivors

Harry Truman's C-118, The Independence
Douglas DC-6B

Several DC-6s are preserved in museums.

Specifications (DC-6B)

Data from Airliners.net[5]

General characteristics

Performance

Note of interest is that the diagram here depicts the sleeper version...note the very small windows above the standard ones. These allowed passengers in their Pullman style bunks to see outside!

See also

Comparable aircraft

Related lists

References

Notes
  1. Purdue University
  2. The Six
  3. "Marcella Mariani" imdb.com. Retrieved: January 22, 2010.
  4. United States Air Force Museum 1975, p. 43.
  5. The Douglas DC-6 Retrieved: March 20, 2006.
Bibliography
  • Pearcy, Arthur. Douglas Propliners: DC-1–DC-7. Shrewsbury, UK: Airlife Publishing, 1995. ISBN 1-85310-261-X.
  • United States Air Force Museum. Wright-Patterson AFB, Ohio; Air Force Museum Foundation , 1975.
  • Whittle, John A. The Douglas DC-6 and DC-7 Series. Tonbridge, Kent, UK: Air Britain (Historians) Ltd., 1971. No ISBN.
  • Yenne, Bill. McDonnell Douglas: A Tale of Two Giants. Greenwich, Connecticut: Bison Books, 1985. ISBN 0-517-44287-6.

External links