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Jet Planes and World War II
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The Development of Jet Engines During The War
Before World War II, in 1939, jet engines primarily existed in labs. The end of the war, however, illustrated that jet engines, with their great power and compactness, were at the forefront of aviation development.
A young German physicist, Hans von Ohain, worked for Ernst Heinkel, specializing in advanced engines, to develop the world's first jet plane, the experimental Heinkel He 178. It first flew on August 27, 1939.
Building on this advancement, German engine designer Anselm Franz developed an engine suitable for use in a jet fighter. This airplane, the Me 262, was built by Messerschmitt. Though the only jet fighter to fly in combat during World War II, the Me 262 spent a significant amount of time on the ground due to its high consumption of fuel. It was often described as a sitting duck for Allied attacks. Meanwhile, in England, Frank Whittle invented a jet engine completely on his own. The British thus developed a successful engine for another early jet fighterthe Gloster Meteor. Britain used it for homeland defense but, due to lack of speed, it was not used to combat over Germany.
The British shared Whittle's technology with the U.S., allowing General Electric (GE) to build jet engines for America's first jet fighter, the Bell XP-59. The British continued to develop new jet engines from Whittle's designs, with Rolls-Royce initiating work on the Nene engine during 1944. The company sold Nenes to the Sovietsa Soviet version of the engine, in fact, powered the MiG-15 jet fighter that later fought U.S. fighters and bombers during the Korean War.
The 1945 surrender of Germany revealed substantial wartime discoveries and inventions. General Electric and Pratt & Whitney, another American engine-builder, added German lessons to those of Whittle and other British designers. Early jet engines, such as those of the Me 262, gulped fuel rapidly. Thus, an initial challenge was posed: to build an engine that could provide high thrust with less fuel consumption.
Pratt & Whitney resolved this dilemma in 1948 by combining two engines into one. The engine included two compressors; each rotated independently, the inner one giving high compression for good performance. Each compressor drew power from its own turbine; hence there were two turbines, one behind the other. This approach led to the J-57 engine. Commercial airlinersthe Boeing 707, the Douglas DC-8flew with it. One of the prominent postwar engines, it entered service with the U.S. Air Force in 1953.
The Man Behind The Engine
Hans von Ohain
Hans von Ohain of Germany was the designer of the first operational jet engine, though credit for the invention of the jet engine went to Great Britain's Frank Whittle. Whittle, who registered a patent for the turbojet engine in 1930, received that recognition but did not perform a flight test until 1941. Ohain was born December 14, 1911, in Dessau, Germany. While pursuing doctorate work at the University of Gottingen, he forumulated his theory of jet propulsion in 1933. After receiving his degree in 1935, he became a junior assistant to Robert Wichard Pohl, director of the university's Physical Institute.
Granted a patent for his turbojet engine in 1936, Ohain joined the Heinkel Company in Rostock, Germany. By 1937 he had built a factory-tested demonstration engine and, by 1939, a fully operational jet aircraft, the He 178. Soon after, Ohain directed the construction of the He S.3B, the first fully operational centrifugal-flow turbojet engine. This engine was installed in the He 178 airplane, which made the world's first jet-powered aircraft flight on August 27, 1939. Ohain developed an improved engine, the He S.8A, which was first flown on April 2, 1941. This engine design, however, was less efficient than one designed by Anselm Franz, which powered the Me 262, the first operational jet fighter aircraft.
Ohain came to the United States in 1947 and became a research scientist at Wright-Patterson Air Force Base,the Aerospace Research Laboratories, Wright's Aero Propulsion Laboratory, and the University of Dayton Research Institute.
During his 32 years of U.S. government service, Ohain published more than 30 technical papers and registered 19 U.S. patents. In 1991 Ohain was honored by the U.S. National Academy of Engineering with the Charles Stark Draper Prize as a pioneer of the jet age. Ohain died on March 13, 1998, at his home in Melbourne, Florida.
The Heinkel He 178 was the world's first jet plane.
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16-03-2004
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