6 of 6 people found the following review helpful
A Partial Explanation,
This review is from: Hans Von Ohain: Elegance in Flight (General Publication) (Hardcover)
Hans von Ohain, shares with Frank Whittle, the credit for independently developing the first viable jet engine. As von Ohain is quoted as saying (pp. 35-36) -
"If I would have looked through the literature on the gas turbine, including the patents, I would have found that there was really nothing new, and my enthusiasm would have been dampened. The turbojet was therefore not a complete novelty. Since I was not familiar with its past history, it was a novelty for me. It helped me not to know what already had been done.
"The Frenchman Guillaume, as I learned much, much later, obtained a patent (international) in 1921, long before anybody else. (It was) on the axial flow compressor, a combustor, and on the turbine to drive the compressor and an exhaust nozzle very much like that of Lorin's ramjet invention of 1913. (He had) already invented the axial flow turbojet engine! Good that I didn't know!"
Here, however, von Ohain was being too modest. As Edward Constant wrote in Genesis N + 1: The origins of the Turbo-Jet revolution
"One myth first needs debunking. The word "invention" appears rarely here; "patent" even more rarely. The turbo-jet was "created." As mentioned, reaction propulsion devices were discussed -as early as the seventeenth century, and numerous devices were patented during the First World War. Indeed, in 1921, a Frenchman named Charles Guillaume patented a complete axial-flow turbo-jet in very nearly its modern form. There was one small difference": Guillaume's patent drawings, in addition to showing the expected compressor, combustion chamber, and turbine, also show, protruding from the front of the engine, a very large manual starting crank. One wonders how aeronautical engineers would have streamlined that. Guillaume's concept, in short, although of the same configuration as a turbo-jet, could not have been further from the valid scientific assumptions that made the turbo-jet a practical possibility. To say that he "invented" the turbojet in any meaningful sense is absurd. Such is true of most antique patents of modern devices. Legalistic quibbling over "invention," "patenting," and "priority" has no relevance here. What matters is actual creation of the turbo-jet and the revolution it ignited."
Once again, quoting Constant-
"Only two men held uncompromisingly to the turbo-jet: Frank Whittle in England and Hans von Ohain in Germany. One other man, Herbert Wagner, also in Germany, initiated an inquiry that led less directly to the turbo-jet, while ... Helmut Schelp, also arrived at the turbo-jet conclusion and promoted a government sponsored turbo-jet program. Finally, a turbo-prop project in England initiated by A. A. Griffith evolved fairly early into a turbo-jet. Those five men created the turbo-jet, were the provocateurs of the turbo-jet revolution. They used prior technology; certain preconditions were perhaps requisite to their work. But theirs personally was the turbo-jet."
There is no doubt that von Ohain had a brilliant and fertile mind as did Whittle. Whittle, of lower middle class background, was trained as an RAF mechanic, became and engineer and them studied the basic sciences. In contrast, von Ohain's family was of the Prussian military aristocracy. His PhD was in physics and learned engineering on the job as described in pp. 58-59
"In a book of cartoons and doggerel poetry made up as a joke by his coworkers in these early months with Heinkel, von Ohain is cited in the ... ABC with this couplet:
"P- "Pabst is ein Erfindermann
doch er niGht konstruieren kann.
"Pabst is an inventor
But he can't build anything.
"Von Ohain said:
"When I worked with the brothers Gunter, I really converted myself completely to what you may call a self-made engineer. I sat down and studied engineering very, very intensively. I knew fluid mechanics very well from Prandtl's lectures. I knew a little bit about stress analysis, so when Prandtl recommended that I get very familiar with stress problems it wasn't difficult for me to apply this knowledge to design of the turbojet. I think that after two years I could cope and compete with any mechanical engineer with respect to engineering design. I think I became a very good engineer."
Von Ohain, in contrast to Whittle found himself excellent academic mentors one of which, arranged for von Ohain to meet Ernst Heinkel who became von Ohain's employer and funder until 1945. This arrangement ensured that von Ohain's work could move ahead rapidly while Whittle languished lacking money, staff, decent facilities or any real sign of interest from the British authorities. One serious lack, they both faced, was of proper component test facilities.
Whittle's decision that the gas turbine was the way of the future, and his conceptual design work date from 1929 while that of von Ohain began in the fall of 1933. Neither had any knowledge of the other's work. Due mainly to Heinkel's support they were neck and neck by 1937 and had built up a substantial lead by 1939. As Constant wrote-
"Heinkel hired von Ohain, then only 24, and Max Hahn, and set them up in a small shop at the Heinkel works.... Work began in April 1936, just a month after Whittle began work, and the von Ohain engine was first run in March, 1937, the same month the Whittle engine was first run.... Von Ohain's, choice of hydrogen as an experimental fuel largely accounted for the nearly two-year development lead he had built up by late 1939."
According to the book (p. 59), the brilliant decision by von Ohain to use hydrogen was due to his strong scientific background.
"In view of the political climate, his tenuous position in the corporation and, most of all, the great impatience of Heinkel, von Ohain could not first develop a well-functioning combustor and then begin an engine design. From previous experience ... it was clear that a poorly functioning combustor could result in a nonfunctioning engine. This could mean the end of the turbojet project. He changed to a two-fold approach. In phase one he would quickly build a simple jet engine of minimum risk using gaseous hydrogen as fuel in order to demonstrate the jet principle in a convincing and impressive manner. Von Ohain was convinced that he could win time to systematically complete a combustor for gasoline if the hydrogen engine was successful.... Von Ohain said that his knowledge of physics brought him to the decision to use hydrogen to run the demonstration engine .... Hydrogen had known properties of high diffusion and flame velocity, plus a wide fuel-air concentration range over which combustion was possible. Von Ohain designed a hydrogen combustor that he was sure would function well and not need time-consuming pretests...."
The character of von Ohain, as portrayed in this book, is of a man possessing humility, honesty and a good sense of humor who had little difficulty winning people's cooperation and loyalty and could delegate effectively. From Whittle's autobiography, I got the impression of a man perpetually tense, humorless, with a gift for alienating people and a micromanager.
There are three areas in which the book is weak
1. Why, for all his brilliance, did the German government decide to produce the Jumo and BMW jet engines in preference to the von Ohain engines?
2. How could such a moral and intelligent man build jet engines for the evil Nazi regime? and,
3. The literary quality of the writing is mediocre, almost naive.
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Initial post: Nov 21, 2007 7:34:11 AM PST
Bryan E. Leed says:
"The literary quality of the writing is mediocre, almost naive." is a bit harsh of an observation, but the book was written with the full cooperation and influence of Hans von Ohain's widow, so it is understandable that this book will not dwell upon the unfortunate oppression that the Nazi regime had upon all of the citizens, and scientists, which they could exercise complete control over, under penalty of death. von Ohain did not promote the Nazi party, but rather immigrated to the USA as soon as it was possible.
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