Tristars and DC-10s Enhanced Trans-Oceanic Travel Before ETOPS
After the advent of the Jet Age, large intercontinental jetliners routinely had four engines. The American Boeing B-707 and B-747, and the Douglas DC-8 designs had four; the British Vickers VC-10 had four as did the DeHavilland Comet. Even the Russian IL-62 and Canadian Avro Canada 102 designs had 4 engines. Prevailing wisdom provided four engines in case one failed over water, the aircraft could limp back on three.
The McDonnell Douglas DC-10 first flew in August,1970. It was designed as a DC-8 replacement. More powerful General Electric and Pratt & Whitney turbofans made a trijet safe, and a bit more efficient. Three main variants were built, the latter two had increased range and a modified landing gear assembly. The MD-11, its successor, retained the same three engine layout. 396 DC-10s were built.
The Lockheed L-1011 Tristar first flew in November, 1970. It was envisioned as a direct competitor to the Boeing B-747 and McDonnell Douglas DC-10. Two main versions were produced, the longer ranged L-1011-500 “Tristar 500” was a smaller, but longer ranged version.
The easiest way to spot the difference between these two jetliners is that the Tristar’s tail engine exhausts through the end of the fuselage via an “S-shaped” duct, while the DC-10’s tail engine runs completely through the vertical stabilizer.
Here’s a look at some of the airlines who utilized these two widebodies… a few airframes have been modified as aerial refuellers (60 were purposely built as USAF KC-10A Extenders too).and other special use missions. You can hover over the thumbnail for a bit more information on them.