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L-1011 vs. DC-10: Battle of the Wide-Body Tri-Jets

Jeffrey Syken

During WWII, U.S. airlines had demonstrated their capacity for reliable and safe service to a wary public. However, in the immediate postwar years, with an increase of 400% in airline bookings, “Air Travel for Everybody” had become a rather unpleasant experience for both John and Jane Q. Public. Though the “as the crow flies” route saved much time as compared to traditional ground travel (i.e. trains), inadequate airport facilities, inefficient processing of both passengers and baggage and the practice of “stacking” (delaying landings) all added up to the time advantages of flight being diminished exponentially. However, with improvements in technology and ground facilities, by the early 1950s, airlines were poised to become a major player in the transportation industry. Reciprocating gasoline engines were being replaced by more efficient gas turbines and the propeller was giving way to the jet, cutting travel times dramatically and allowing for smoother, higher and more comfortable flights. With the introduction of the Boeing 707 in 1958, the “Jet-Age” had commenced, making trans-Atlantic and trans-Continental flights a practical reality. With Boeing’s introduction of the 747-100 in 1969, the cost of jet travel was dramatically decreased given the plane’s greater capacity and more powerful, fuel-efficient (and quieter) “high-bypass” turbofan engines. One of the most impressive aspects of the world’s first “Jumbo” jet was its roominess, which the public found very appealing (as compared to the tube-like feeling inside first generation passenger jets such as the 707 and DC-8). There was, however, logistical problems associated with such a large aircraft. The routes it could serve were limited due to the passenger volume necessary to make it profitable and there were limited number of airports that could accommodate the 747. That got both airline and aircraft executives to thinking about a plane that could take the “Wide-Body” concept, with all its appeal, and apply it to a medium-range aircraft that could satisfy the FAA’s “60-minute” rule, which applied to four-engine aircraft (the “30-minute” rule applied to two-engine aircraft). The compromise solution to the 60-minute rule was a “Tri-Jet,” with three engines, that would satisfy the FAA’s requirement in the same way a four-engine aircraft could. The question now became where to place a third engine. For Lockheed’s L-1011 TriStar, the answer would be in the aft section of the fuselage with airflow provided by an “S-duct” (akin to the highly successful Boeing 727). For McDonnell Douglas’ DC-10, the answer would be integral with the vertical stabilizer – both would have their advantages and disadvantages. Thus, the “Era of the Airbus” began in earnest in the early 1970s with the introduction of these two wide-body tri-jets. For Lockheed, the premier U.S. defense contractor, it would be a technical coup but a financial disaster which, ultimately, motivated them to withdraw permanently from the commercial airliner market by the mid-1980s. For McDonnell Douglas, the DC-10 would have a mixed legacy, having sold more aircraft but with a dismal record of over fifty serious accidents. In the end, two engines would prove more viable than three with the coming of the energy crisis and its associated technological advances (i.e. “supercritical wing” and more fuel-efficient high-bypass turbofan jet engines).

This course includes a multiple-choice quiz at the end, which is designed to enhance the understanding of the course materials.

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