Thursday, October 1, 2009

The Lockheed Constellation (Connie)

The Lockheed Constellation (Connie) was a four engine (each with 18 pistons of Radial design, the Wright R-3350) propeller-driven airliner built by Lockheed between 1943 and 1958 at its Burbank, California, USA, facility. A total of 856 aircraft were produced in four models, all distinguished by a triple-tail design and dolphin-shaped fuselage. The Constellation was used as a civilian airliner and as a U.S. military air transport plane, seeing service in the Berlin Airlift. It was the presidential aircraft for U.S. President Dwight D. Eisenhower.
Constellation

Super Constellation

C-69 / C-121



A Qantas Empire Airways L-749 Constellation.
Role
Airliner
Manufacturer
Lockheed
First flight
January 9, 1943
Introduced
1943 with USAAF

1945 with TWA
Retired
1967, airline service

1978, military
Primary users
Trans World Airlines

United States Army Air Forces
Produced
1943–1958
Number built
856
Variants
EC-121 Warning Star

Initial design studies

Since 1937, Lockheed had been working on the L-044 Excalibur, a four-engine pressurized airliner. In 1939, Trans World Airlines, at the encouragement of major stockholder Howard Hughes, requested a 40-passenger transcontinental airliner with 3,500 mi (5,630 km) range[1] - well beyond the capabilities of the Excalibur design. TWA's requirements led to the L-049 Constellation, designed by Lockheed engineers including Kelly Johnson and Hall Hibbard.[2] Willis Hawkins, another Lockheed engineer, maintains that the Excalibur program was purely a cover for the Constellation.

   Development of the Constellation

The Constellation's wing design was close to that of the P-38 Lightning, differing mostly in scale.  The distinctive triple tail kept the aircraft's overall height low enough to fit in existing hangars,  while new features included hydraulically-boosted controls and a thermal de-icing system used on wing and tail leading edges.[ The plane had a top speed of over 340 mph (547 km/h), a cruise speed of 300 mph (483 km/h), and a service ceiling of 24,000 ft (7,315 m).

According to Anthony Sampson in Empires of the Sky, the intricate design may have been undertaken by Lockheed, but the concept, shape, capabilities, appearance and ethos of the Constellation were driven by Hughes' intercession during the design process.

With the onset of World War II, the TWA aircraft entering production were converted to an order for C-69 Constellation military transport aircraft, with 202 aircraft intended for the United States Army Air Forces (USAAF). The first prototype (civil registration NX25600) flew on January 9, 1943, a simple ferry hop from Burbank to Muroc Field for testing.[1] Eddie Allen, on loan from Boeing, flew left seat, with Lockheed's own Milo Burcham as copilot. Rudy Thoren and Kelly Johnson were also on board.

Lockheed proposed model L-249, which was to be a long range bomber. It received the military designation XB-30 but the aircraft was not developed. A plan for a very long-range troop transport, the C-69B, was canceled. A single C-69C, a 43-seat VIP transport, was built in 1945 at the Lockheed-Burbank plant.

The C-69 was mostly used as a high-speed, long-distance troop transport during the war.  22 C-69s were completed before the end of hostilities, and not all of those entered military service. The USAAF cancelled the remainder of the order in 1945.

After World War II, the Constellation soon came into its own as a popular, fast, civilian airliner. Aircraft already in production for the USAAF as C-69 transports were finished as civilian airliners, with TWA receiving the first on 1 October 1945. The first transatlantic proving flight departed Washington, DC on December 3, 1945, arriving in Paris on December 4, via Gander and Shannon.

Trans World Airlines opened post-war commercial intercontinental air service on February 6, 1946, with a New York-Paris flight in a Constellation. On June 17, 1947, Pan American World Airways opened the first ever regularly-scheduled around-the-world service with their L749 Clipper America. The famous flight Pan Am 101 operated for over 40 years.

As the first pressurized airliner in widespread use, the Constellation helped to usher in affordable and comfortable air travel. Operators of Constellations included TWA, Eastern Air Lines, Pan American World Airways, Air France, BOAC, KLM, Qantas, Lufthansa, Iberia Airlines, Panair do Brasil, TAP Portugal, Trans-Canada Airlines (later renamed Air Canada), Aer Lingus and VARIG.

Initial difficulties

The Constellation airliner had three accidents in the first ten months of service, temporarily curtailing its career as a passenger airliner. On June 18, 1946, the engine of a Pan American aircraft caught fire and fell off. The flight crew made an emergency landing with no loss of life. However, on July 11, a Transcontinental and Western Air aircraft fell victim to an in-flight fire, crashing in a field and taking the lives of five of the six on board The accidents prompted the suspension of the Constellation's airworthiness certificate until Lockheed could modify the design. This was dramatized in the motion picture The Aviator (2004) during the scene where Howard Hughes (played by Leonardo DiCaprio) surveys numerous grounded TWA Constellations.

The Constellation proved prone to engine failures (due to her R3350s), earning the nickname "World's Finest Trimotor" in some circles.

Records

Sleek and powerful, Constellations set a number of records. On April 17, 1944, the second production L049, piloted by Howard Hughes and TWA president Jack Frye, flew from Burbank, California to Washington, D.C. in 6 hours and 57 minutes (c. 2,300 mi/3,701 km at an average 330.9 mph/532.5 km/h). On the return trip, the aircraft stopped at Wright Field to give Orville Wright his last flight, more than 40 years after his historic first flight. He commented that the Constellation's wingspan was longer than the distance of his first flight.

On September 29, 1957, a L1649A Starliner flew from Los Angeles to London in 18 hours and 32 minutes (approximately 5,420 mi/8,723 km at 292.4 mph/470.6 km/h). The L1649A holds the record for the longest-duration non-stop passenger flight — during TWA's inaugural London to San Francisco flight on October 1-2 1957, the aircraft stayed aloft for 23 hours and 19 minutes (approximately 5,350 mi/8,610 km at 229.4 mph/369.2 km/h)

Obsolescence

The advent of jet airliners, with the de Havilland Comet, Boeing 707, Douglas DC-8 and Convair 880, rendered the piston-engined Constellation obsolete. The first routes lost to jets were the long overseas routes, but Constellations continued to fly domestic routes. The last scheduled passenger flight of a four-engined piston-engined airliner in the United States was made by a TWA L749 on May 11, 1967 from Philadelphia to Kansas City, MO. However, Constellations remained in freight service for years to come, and were the mainstay of Eastern Airlines' shuttle service between New York, Washington, and Boston until 1968.

One of the reasons for the elegant appearance of the aircraft was the fuselage shape - a continuously variable profile with no two bulkheads the same shape. Unfortunately, this construction is very expensive and was replaced by the mostly tube-shape of modern airliners. The tube is more resistant to pressurization changes and cheaper to build.

With the shutdown of Constellation production, Lockheed elected not to develop a first-generation jetliner, instead sticking to its lucrative military business and production of the modest turboprop-powered Lockheed L-188 Electra airliner. Lockheed would not build a large civil passenger aircraft again until its L-1011 Tristar debuted in 1972. While a technological marvel, the L-1011 was a commercial failure, and Lockheed left the commercial airliner business permanently in 1983.

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