1. Design and development

2. Variants
    Air Force  Navy 

3. Specifications
    C-121A (L-749A)  R7V-1/C-121J (L-1049B) 

4. See also

5. References
    Notes  Bibliography 

6. External links

The Lockheed C-121 Constellation is a military transport version of the Lockheed Constellation. A total of 332 aircraft were constructed for both the United States Air Force and United States Navy for various purposes. Numerous airborne early warning versions were also constructed. The C-121 later saw service with smaller civilian operators until 1993.

Design and development

Lockheed's first attempt at a military version of the Constellation airliner had been unsuccessful. This was largely due to the problems encountered by the Wright R-3350 engines that powered the aircraft. After the war, the few military Constellations built (designated C-69) were retrofitted by Lockheed for use in the post-war airline industry as the L-049.

In 1947, Lockheed unveiled a more economical Constellation. The L-749 as it was known, had extra fuel capacity and a more economical version of the R-3350. However, Lockheed had lost 1200 workers that same year. By 1948, production of the L-749 was at a near halt. It was then that the United States Air Force (USAF) signed a contract with Lockheed for ten L-749A aircraft designated the C-121A. The United States Navy (USN) had also placed an order for two AWACS versions of the L-749A designated the PO-1W (later WV-1). The first L-749A variants off the production line were for the US military.

The C-121A versions differed from the L-749 only through having a reinforced floor to handle cargo, and a large aft loading door. Although originally intended for cargo transport duties, they were usually fitted out with 44-seat passenger transport interiors. The aircraft also consisted of a five-man crew with four relief crew members on standby. All C-121As were assigned to the Atlantic division of the Military Air Transport Service (MATS). The aircraft would later see service in the Berlin Airlift. Dwight Eisenhower and General Douglas MacArthur both used the C-121A as their personal VIP transports. In 1950, six of the C-121A Constellations were modified as VIP transports and redesignated VC-121A. The last C-121As were retired in 1968.

In August 1950, the USN ordered eleven passenger/cargo convertible versions of Lockheed's stretched L-1049B Super Constellation (which it had already ordered as the WV-2 AWACS platform). These aircraft, originally designated R7O, were delivered before the WV-2 aircraft due to the R7O being more simple to produce. The R7O (now R7V-1) first flew in 1952. The R7V-1 was able to be quickly converted between a passenger transport for 97-107 individuals or a cargo carrying transport in two hours. The Navy reduced the number of available seats to fit room for life rafts on overseas flights. 73 stretchers could also be used for medical evacuation flights. The R7V-1s saw service over the Atlantic and Pacific in squadrons VR-1 (the oldest transport squadron in the Navy), VR-7 and VR-8. Two modified R7V-1 aircraft were used on Antarctic supply missions while conducting tests and observations at the same time. One crashed on landing in 1970 and remains at the spot to the present day; the other was retired in 1971. In 1962, 32 of the 50 R7V-1 aircraft in Naval service were transferred to the Air Force, being re-designated the C-121G. The remaining 18 in Naval service were redesignated C-121J. One C-121J was later used by the Blue Angels until it was replaced by a Lockheed C-130 Hercules in 1971.

The USAF had also ordered 33 L-1049F Super Constellations in 1951, designated the C-121C. Unlike its Naval equivalent, the C-121C featured square cabin windows instead of round ones. Otherwise, the C-121C resembled the USN R7V-1 aircraft. The C-121C also featured a reinforced structure to handle turboprop engines if necessary. Other features of the C-121C included an Auxiliary Power Unit Turbo-compound R-3350s and the ability to carry 75 passengers, 72 fully equipped troops, or 47 stretchers. The seats could be stored under the floor of the aircraft when needed for cargo use. The first flight of a C-121C was in 1955. Deliveries began in August 1955, with aircraft being assigned to the MATS Atlantic division. The aircraft were later in service with the Air National Guard (ANG) and were retired in 1973. Four were later refitted as VC-121C VIP aircraft, six as EC-121S TV and radio broadcast relay systems, two became EC-121C Microwave Airborne Radio Communications (MARCOM) systems and one was converted to a DC-121C observation aircraft.

After military service, some C-121s and R7V-1s were used by civilian operators as cargo aircraft. The last operators were small Dominican Republic cargo airlines that operated to Miami with surplus military Constellations bought from Davis-Monthan Air Force Base. The operations stopped in 1993 after the Federal Aviation Administration (FAA) banned these operators from flying into the United States due to safety concerns. Two former C-121Cs fly today with the Historical Aircraft Restoration Society of Australia and the Super Constellation Flyers Association of Switzerland.^[1][2]

Variants

Air Force

C-121A

Initial variant, based on the civil L-749 Constellation. Nine built.

VC-121A

Six C-121A transports converted to VIP use. Originally designated PC-121A.

VC-121B

Similar to the VC-121A, but with the cargo door replaced by a smaller passenger door. One built.

C-121C

Initial variant based on the L-1049 Super Constellation. 33 built.

VC-121C

VIP conversion of four C-121C aircraft.

VC-121E

Ordered by the United States Navy as a R7V-1 but modified before delivery as a presidential transport for the United States Air Force.

//Lockheed L-1249 Super Constellation">YC-121F

Two former United States Navy R7V-2s with Pratt & Whitney T34 turboprop engines transferred to the United States Air Force. Designated L-1249A by Lockheed.^[3]

C-121G

Redesignation of 32 R7V-1 transports transferred from the USN to the Air Force.

TC-121G

Three C-121Gs converted to AWACS crew trainers.

VC-121G

One C-121G converted to a VIP transport.

Navy

R7V-1

Initial Navy version based on the L-1049. 50 built. Originally designated R7O.

R7V-1P

One R7V-1 modified for Antarctic service.

//Lockheed L-1249 Super Constellation">R7V-2

Two transport aircraft similar to the YC-121F. Also designated L-1249A. Two built.

C-121J

18 remaining R7V-1s redesignated.

TC-121J

Electronic testbed. One converted.

NC-121J

Four C-121J aircraft converted to television broadcasting aircraft for use in Vietnam. Project Jenny ( Blue Eagles ) VXN-8

VC-121J

Four C-121J aircraft converted for VIP use. One operated with the Blue Angels.

Specifications

C-121A (L-749A)

|ref=Lockheed Constellation:From Excalibur to Starliner.^[5]

|crew=5
|capacity=44 Passengers (Passenger configuration)
|payload main=
|payload alt=
|payload more=
|length main= 95 ft 2 in
|length alt= 29.007 m
|span main= 123 ft
|span alt= 37.49 m
|height main= 22 ft 5 in
|height alt= 6.8326 m
|area main= 1,650 sq ft
|area alt= 153.29 sq m
|airfoil=
|aspect ratio=
|empty weight main= 61,325 lbs
|empty weight alt= 27,816.6 kg
|loaded weight main=
|loaded weight alt=
|useful load main=
|useful load alt=
|max takeoff weight main= 107,000 lbs
|max takeoff weight alt= 48,534.4 kg
|more general=

|engine (jet)=
|type of jet=
|number of jets=
|thrust main=
|thrust alt=
|thrust original=
|afterburning thrust main=
|afterburning thrust alt=
|engine (prop)= Wright R-3350-75
|type of prop=radial engines
|number of props=4
|power main= 2,500 bhp
|power alt= 1,866 kW
|power original=
|propeller or rotor?=propeller
|propellers=4
|number of propellers per engine=1
|propeller diameter main=
|propeller diameter alt=

|max speed main= 334 mph
|max speed alt= 537.52 km/h
|max speed more=
|cruise speed main= 324 mph
|cruise speed alt= 521.43 km/h
|cruise speed more=
|stall speed main=
|stall speed alt=
|stall speed more=
|never exceed speed main=
|never exceed speed alt=
|range main=
|range alt=
|range more=
|combat radius main=
|combat radius alt=
|combat radius more=
|ferry range main=
|ferry range alt=
|ferry range more=
|endurance=
|ceiling main= 24,442 ft
|ceiling alt= 7,450 m
|ceiling more=
|climb rate main=
|climb rate alt=
|climb rate more=
|sink rate main=
|sink rate alt=
|sink rate more=
|loading main=
|loading alt=
|thrust/weight=
|power/mass main=
|power/mass alt=
|more performance=

|armament=
|guns=
|bombs=
|rockets=
|missiles=
|hardpoints=
|hardpoint capacity=
|hardpoint rockets=
|hardpoint missiles=
|hardpoint bombs=
|hardpoint other=
|avionics=
}}

R7V-1/C-121J (L-1049B)

|ref=Lockheed Constellation:From Excalibur to Starliner.^[6]

|crew=4
|capacity=97-107 Passengers (Passenger configuration)
|payload main=
|payload alt=
|payload more=
|length main= 116 ft 2 in
|length alt= 35.408 m
|span main= 123 ft
|span alt= 37.49 m
|height main= 24 ft 9 in
|height alt= 7.5438 m
|area main= 1,650 sq ft
|area alt= 153.29 sq m
|airfoil=
|aspect ratio=
|empty weight main= 72,815 lbs
|empty weight alt= 33,028.3 kg
|loaded weight main=
|loaded weight alt=
|useful load main=
|useful load alt=
|max takeoff weight main= 145,000 lb
|max takeoff weight alt= 65,770.9 kg
|more general=

|engine (jet)=
|type of jet=
|number of jets=
|thrust main=
|thrust alt=
|thrust original=
|afterburning thrust main=
|afterburning thrust alt=
|engine (prop)= Wright R-3350-34
|type of prop=radial engines
|number of props=4
|power main= 3250 bhp
|power alt= 2,240 kW
|power original=
|propeller or rotor?=propeller
|propellers=4
|number of propellers per engine=1
|propeller diameter main=
|propeller diameter alt=

|max speed main= 368 mph at 20,000 ft
|max speed alt= 592.24 km/h at 6.096 km
|max speed more=
|cruise speed main= 259 mph at 10,000 ft
|cruise speed alt= 416.82 km/h at 3.048 km
|cruise speed more=
|stall speed main=
|stall speed alt=
|stall speed more=
|never exceed speed main=
|never exceed speed alt=
|range main=
|range alt=
|range more=
|combat radius main=
|combat radius alt=
|combat radius more=
|ferry range main=
|ferry range alt=
|ferry range more=
|endurance=
|ceiling main= 24,442 ft
|ceiling alt= 7,449 m
|ceiling more=
|climb rate main=
|climb rate alt=
|climb rate more=
|sink rate main=
|sink rate alt=
|sink rate more=
|loading main=
|loading alt=
|thrust/weight=
|power/mass main=
|power/mass alt=
|more performance=

|armament=
|guns=
|bombs=
|rockets=
|missiles=
|hardpoints=
|hardpoint capacity=
|hardpoint rockets=
|hardpoint missiles=
|hardpoint bombs=
|hardpoint other=
|avionics=
}}

See also

• Lockheed C-69 Constellation
• Lockheed Constellation
• Lockheed EC-121 Warning Star
• Lockheed L-049 Constellation
• Lockheed L-649 Constellation
• Lockheed L-749 Constellation
• Lockheed L-1049 Super Constellation
• Lockheed L-1249 Super Constellation (R7V-2/YC-121F)
• Lockheed L-1649 Starliner

• Boeing 377 Stratocruiser
• Boeing C-97 Stratofreighter
• Boeing KC-97 Stratofreighter
• Bristol Britannia
• Canadair CC-109 Cosmopolitan
• Convair C-131 Samaritan
• Douglas C-54 Skymaster
• Douglas DC-6/C-118 Liftmaster
• Douglas DC-7
• Ilyushin Il-18

• List of Lockheed aircraft
• List of Lockheed Constellation operators
• Lockheed Constellation variants

References

Notes

Bibliography

• Breffort, Dominique. Lockheed Constellation: from Excalibur to Starliner Civilian and Military Variants. Paris: Histoire and Collecions, 2006. Print. {{ISBN|2-915239-62-2}}.
• Winchester, Jim. Lockheed Constellation (Classic Airliners). St Paul, MN:MBI Publishing 2001. {{ISBN|0-7603-1198-6}}.

External links

• Lockheed Constellation Survivors - A website that explains information and whereabouts of surviving Constellations of all variants, including the Super Constellation.

• Donald L. Bren
• Donald L. Bryant Jr.
• Donald L. Bryant, Jr.
• Donald L. Conner House
• Donald L. Cunningham
• Donald Leach (physicist)
• Donald Leach (Scottish physicist)
• Donald Lee (cricketer)
• Donald Lee Leshnock
• Donald Leshnock
• Donald Leslie Gemmell
• Donald Lewis Shaw
• Donald L. Heflin
• Donald Li
• Donald Liao
• Donald Liddle
• Donald Liebenberg
• Donald Limon, KCB
• Donald Limon KCB
• Donald Lindsay Mathieson
• Donald Lloyd-Jones
• Donald L. Morton
• Donald L. Munro
• Donald Locher
• Donald Loftus Page