on to power the famous MiG-15. American and Soviet designs, independent axial-flow types, for the most part, would strive to attain superior performance until the 1960s, although the General Electric J47 provided excellent service in the F-86 Sabre in the 1950s. By the 1950s, the jet engine was almost universal in combat aircraft, with the exception of cargo, liaison, and other specialty types. By this point some of the British designs were already cleared for civilian use, and had appeared on early models like the de Havilland Comet and Avro Canada Jetliner. By the 1960s all large civilian aircraft were also jet powered, leaving the piston engine in such low-cost niche roles such as cargo flights. Relentless improvements in the turboprop pushed the piston engine (an internal combustion engine) out of the mainstream entirely, leaving it serving only the smallest general aviation designs and some use in drone aircraft. The ascension of the jet engine to almost universal use in aircraft took well under twenty years. However, the story was not quite at an end, for the efficiency of turbojet engines was still rather worse than piston engines, but by the 1970s with the advent of high bypass jet engines, an innovation not foreseen by the early commentators like Edgar Buckingham, at high speeds and high altitudes that seemed absurd to them, only then did the fuel efficiency finally exceed that of the best piston and propeller engines, and the dream of fast, safe, economical travel around the world finally arrived, and their dour, if well founded for the time, predictions that jet engines would never amount to much, were killed forever. See also Aerodynamics History of rockets History of the internal combustion engine Mechanical engineering References History of aviation History of mechanical engineering Jet engines