Did you know…
Why did Lockheed never have an L-1349 model?
Short answer
Because, according to Dominique Breffort's book on the aircraft, no design ever carried that designation, possibly out of superstition over a number starting with 13. In the variant list, the series jumps from the L-1249, the internal name of the R7V-2 and YC-121F, straight to the L-1449, a turboprop that never left the drawing board.

A logical numbering system
Lockheed designated the versions of its Constellation family with codes ending in 49: L-049 for the original model, L-649 and L-749 for the first improved civilian versions, and L-1049 for the stretched Super Constellation. The L-649, with R-3350-749C18BD engines and up to 81 seats, flew on October 19, 1946, and the L-749, with 23,640 liters of fuel to cross the Atlantic nonstop, on March 14, 1947. From the L-1049 onward, each new study climbed to a new hundred: the L-1149 was a proposed version of the L-1049G and the L-1049H with Allison turboprops, and L-1249A was the internal designation of the Navy's R7V-2 and the Air Force's YC-121F, while the L-1249B, a turboprop passenger version, never left the drawing board.
The gap at 13
After the L-1249 should have come the L-1349, but the Constellation variant list shows it as unidentified. Dominique Breffort, author of a book devoted to the aircraft, maintains that no design ever carried that designation, pointing to superstition as a possible explanation. The numbering continues with the L-1449, a proposed turboprop based on the L-1049G with a stretched fuselage and a new wing, and with the L-1549, an even longer version of the L-1449. Both remained projects.
The end of the saga
The family ended with the L-1649A Starliner, the production version fitted with Turbo Cyclone R-3350-988TC18EA-2 engines. It was the last major passenger development of a saga that had begun as military transport in the Second World War and that, between projects, prototypes and production versions, filled a long list of designations with one striking absence.
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