The first production L-1049 flew on July 14 , 1951 and received certification in November 1951 . The Turbo-compound versions of the R-3350 engine were not yet available for civil use , leaving Lockheed to use a less powerful version . The aircraft entered service with Eastern Air Lines in December 1951 flying Miami to New York . Eastern would later operate the L-1049C and L-1049G . TWA 1049s began flying in 1952 ; TWA L-1049Gs flew transatlantic starting in 1955 . In 1956 a TWA L-1049 collided with a United Airlines DC-7 over the Grand Canyon , leading to the deaths of all on both aircraft
collided with a United Airlines DC-7
1956 Grand Canyon mid-air collision
Lockheed L-1049 Super Constellation