Ohain, Hans Joachim Pabst von

▪ 1999

      German aeronautical engineer (b. Dec. 14, 1911, Dessau, Ger.—d. March 13, 1998, Melbourne, Fla.), designed the HeS3b, the turbojet engine that powered the experimental first jet aircraft, the He178, on its historic maiden flight on Aug. 27, 1939, near the German port city of Rostock. Ohain conceived his theory of jet propulsion in 1933 while pursuing a doctorate in physics at the University of Göttingen. After graduating in 1935, he was recommended by the university to the German aircraft manufacturer Ernst Heinkel. Ohain joined Heinkel's firm in 1936, and by September 1937 he had built a factory-tested demonstration engine. Shortly afterward, Ohain directed the construction of the HeS3b, the first fully operational centrifugal-flow turbojet engine. Although the development of this technology did not pique the interest of the German High Command during World War II, it revolutionized postwar transportation and defense. After the war Ohain was recruited by the U.S. Air Force, and he became the chief scientist at Wright Patterson Air Force Base in Dayton, Ohio. After retiring in 1979, he served as a consultant to the University of Dayton Research Institute. Ohain, however, was not credited with being the first to invent the jet engine. Great Britain's Sir Frank Whittle registered a patent for the turbojet engine in 1930, though he did not perform a flight test until 1941. In 1991 Ohain (along with Whittle) was honoured by the U.S. National Academy of Engineering with the Charles Stark Draper Prize as a pioneer of the jet age.

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▪ German designer

born Dec. 14, 1911, Dessau, Ger.

died March 13, 1998, Melbourne, Fla., U.S.

      German designer of the first operational jet engine.

      After obtaining his doctorate at the University of Göttingen, he became a junior assistant to Hugo von Pohl, director of the Physical Institute there. When the German aircraft builder Ernst Heinkel asked the university for assistance in design, Pohl recommended Ohain, who joined Heinkel's manufacturing firm in 1936. Ohain's experiments, carried out in secret at Heinkel's factory, resulted in a bench test by 1937 and a fully operational jet aircraft, the He 178, by 1939. This plane made the world's first jet-powered aircraft flight on Aug. 27, 1939. Ohain's centrifugal-flow turbojet engine, the HeS 3B, performed perfectly, though the landing gear of the plane failed to retract, preventing the test pilot from accelerating to planned speed.

      Ohain continued his work, developing an improved engine, the HeS 8A, which was first flown on April 2, 1941. Ohain's engine design, which used a centrifugal compressor, was inherently less efficient than one using an axial-flow compressor, and it was a turbojet of this type, designed by Anselm Franz, that powered the Me 262, the world's first operational jet fighter aircraft. Ohain's engines, by comparison, saw little use in World War II. After the war Ohain resettled in the United States, where he worked on jet aircraft for the U.S. Air Force.

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