A jet aircraft is an aircraft propelled by jet engines. Jet aircraft fly much faster than propeller-powered aircrafts and at higher altitudes -- as high as 10,000 to 15,000 meters (about 33,000 to 49,000 ft). At these altitudes, jet engines achieve maximum efficiency over long distances. The engines in propeller powered aircraft achieve their maximum efficiency at much lower altitudes. Jet aircraft can move faster than sound.
Henri Coandă, a Romanian Engineer, was the first to build a jet plane in 1910 - the Coanda-1910. Later on, two engineers, Frank Whittle in the United Kingdom and Hans von Ohain in Germany, developed the concept independently during the late 1930s, although credit for the first turbojet is given to Whittle.[citation needed] The concept had already been discussed as early as August 1928 by Frank Whittle at Flying School, Wittering, but Hans von Ohain also wrote in February 1936 to Ernst Heinkel, telling him of the design and its possibilities. However, it can be argued that A. A. Griffith, who published a paper in July 1926 on compressors and turbines, which he had been studying at the RAE, also deserves priority credit,perhaps more than either Frank Whittle or Hans von Ohain
Henri Coandă, a Romanian Engineer, was the first to build a jet plane in 1910 - the Coanda-1910. Later on, two engineers, Frank Whittle in the United Kingdom and Hans von Ohain in Germany, developed the concept independently during the late 1930s, although credit for the first turbojet is given to Whittle.[citation needed] The concept had already been discussed as early as August 1928 by Frank Whittle at Flying School, Wittering, but Hans von Ohain also wrote in February 1936 to Ernst Heinkel, telling him of the design and its possibilities. However, it can be argued that A. A. Griffith, who published a paper in July 1926 on compressors and turbines, which he had been studying at the RAE, also deserves priority credit,perhaps more than either Frank Whittle or Hans von Ohain
Modern jet aircraft
Modern airliners cruise at speeds of 0.75 to 0.85 Mach, or 75% to 85% of the speed of sound (420 to 580 mph/ 680-900 km/h). The speed of sound predominantly depends on air temperature (hardly at all on pressure), so the Mach number for the speed of a jet also varies with atmospheric conditions. NASA and the US Federal Aviation Administration have been promoting Very Light Jets: small general aviation aircraft seating 4 to 8 passengers
Other jets
Most people use the term 'jet aircraft' to denote gas turbine based airbreathing jet engines, but rockets and scramjets are both also propelled by jets.
The fastest airbreathing jet aircraft is the unmanned X-43 scramjet at around Mach 9-10. The fastest manned (rocket) aircraft is the X-15 at Mach 6.85.
The Space Shuttle, while far faster than the X-43 or X-15, is not regarded as a jet aircraft during ascent, nor during reentry and landing (as it is unpowered during this phase of operation
Most people use the term 'jet aircraft' to denote gas turbine based airbreathing jet engines, but rockets and scramjets are both also propelled by jets.
The fastest airbreathing jet aircraft is the unmanned X-43 scramjet at around Mach 9-10. The fastest manned (rocket) aircraft is the X-15 at Mach 6.85.
The Space Shuttle, while far faster than the X-43 or X-15, is not regarded as a jet aircraft during ascent, nor during reentry and landing (as it is unpowered during this phase of operation
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