L-749

L-749 Constellation
A Trans World Airlines L-749A at London's Heathrow Airport. Note the "Speedpak" under fuselage freight container.
Role	Airliner
National origin	United States
Manufacturer	Lockheed
Designer	Clarence "Kelly" Johnson
First flight	March 14, 1947
Introduction	April 18, 1947
Retired	1993
Primary users	Trans World Airlines Air France KLM Eastern Air Lines
Produced	1947 - 1951
Number built	119
Developed from	Lockheed L-649 Constellation
Variants	Lockheed C-121 Constellation Lockheed PO-1W/WV-1 Constellation

The Lockheed L-749 Constellation was the first Lockheed Constellation to regularly cross the Atlantic Ocean non-stop. Although similar in appearance to the L-649 before it, the L-749 had a larger fuel capacity, strengthened landing gear, and eventually weather radar.

In early 1947, the Lockheed Aircraft Corporation unveiled the L-749, a derivative of its L-649 Constellation with fuel tanks to increase its range by 1,000 miles (1,600 km). Due to the increased weight, the landing gear and tires had to be strengthened. Jet stacks were also introduced, increasing speed by 15 miles per hour (24 km/h). These jet stacks increased the noise, requiring more insulation. As with the L-649, ten different layouts of the internal cabin were possible. Airlines originally attracted to the L-649 changed their orders to the L-749. The L-749 was to become the standard version of the regular Constellation.

The L-749 first flew on March 14, 1947, and received certification that same month. The first L-749 was delivered to Air France on April 18, 1947. Pan American World Airways received its first L-749 in June, and L-749 service began the same month on their "Round The World" service. The L-749 also entered service with various other airlines, including Trans World Airlines (TWA), KLM, Cubana de Aviación, Línea Aeropostal Venezolana and Avianca.

In March 1947, 1,200 jobs were lost at Lockheed, bringing production of the aircraft to a near stand-still. A large order from the United States Air Force for 10 L-749As, designated C-121 Constellation, saved the Constellation program from cancellation. The United States Navy followed in, ordering two L-749As as PO-1Ws (later WV-1s). The first L-749A off the production lines were destined for the military.

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Wikipedia