von Ohain Hans @·AIRCRAFTUBE

  • Hans von Ohain Hans von Ohain
    Hans von Ohain
  • von Ohain and Ernst Heinkel<br>celebrate the first jet flight von Ohain and Ernst Heinkel<br>celebrate the first jet flight
    von Ohain and Ernst Heinkel
    celebrate the first jet flight
  • Hans von Ohain and the Heinkel HeS 3A Hans von Ohain and the Heinkel HeS 3A
    Hans von Ohain and the Heinkel HeS 3A
  • At age 25 At age 25
    At age 25
  • The Heinkel He 280 V2 The Heinkel He 280 V2
    The Heinkel He 280 V2
  • Frank Whittle<br>and<br>Hans von Ohain Frank Whittle<br>and<br>Hans von Ohain
    Frank Whittle
    and
    Hans von Ohain
  • Hans Joachim Pabst von Ohain Hans Joachim Pabst von Ohain
    Hans Joachim Pabst von Ohain
  • The Heinkel He 178 The Heinkel He 178
    The Heinkel He 178
  • The HeS 3 turbojet engine (replica) The HeS 3 turbojet engine (replica)
    The HeS 3 turbojet engine (replica)
  • The Heinkel He S-8A The Heinkel He S-8A
    The Heinkel He S-8A

Hans von Ohain

Dessau (Germany) 14 December 1911 – † Melbourne (Florida) 13 March 1998

Hans Joachim Pabst von Ohain was a German physicist, the designer of the first operational jet engine. His first design ran in March 1937, and it was one of his engines that powered the world's first flyable all-jet aircraft, the prototype of the Heinkel He 178 (He 178 V1) in late August 1939. In spite of these early successes, other German designs quickly eclipsed Ohain's, and none of his engine designs entered widespread production or operational use.

Ohain started to develop his first turbojet engine designs independently during the same period that Frank Whittle was working on his own similar designs in Britain, and their turbojet designs are said by some to be an example of simultaneous invention. However, Frank Whittle was already working on his design in the late 1920s and openly patented the design in 1930, a full seven years before Ohain's design ran. Ohain's first jet engine, the Heinkel HeS 1, ran successfully in April 1937, the same month that Whittle's first engine, the Power Jets WU First Model, also ran successfully. Ohain's jet engine was the first to fly operationally within the Heinkel He 178 aircraft in 1939, which was followed by Whittle's engine with-in the Gloster E.28/39 in 1941. Operational jet fighter aircraft from both Germany and Britain entered operational use virtually simultaneously in July, 1944. After the war the two men met and became friends.

Early life and jet development

Born in Dessau, Germany, Ohain graduated PhD in Physics and Aerodynamics from the University of Göttingen, then one of the major centers for aeronautical research, having attended lectures by Ludwig Prandtl. In 1933, while still a student, he conceived what he called "an engine that did not require a propeller."

After receiving his degree in 1935, Ohain became the junior assistant of Robert Wichard Pohl, then director of the Physical Institute of the University. In 1936, while working for Pohl, Ohain registered a patent on his version of a jet engine, Process and Apparatus for Producing Airstreams for Propelling Airplanes. Unlike Frank Whittle's Power Jets WU design, Ohain's used a centrifugal compressor and turbine placed very close together, back to back, with the flame cans wrapped around the outside of the assembly.

While working at the University, Ohain often took his sports car to be serviced at a local garage, Bartles and Becker. Here he met an automotive mechanic, Max Hahn, and eventually arranged for him to build a model of his design for around 1,000 Reichsmark. The completed model was even larger in diameter than Whittle's fully working engine of 1937, although much shorter along its thrust axis. Ohain took the model to the University for testing but ran into serious problems with combustion stability. Often the fuel would not burn inside the flame cans and would be blown through the turbine, sending flames shooting out in the airstream and overheating the electric motor powering the compressor.

Heinkel

In February 1936, Pohl wrote to Ernst Heinkel, telling him about Ohain's design and its possibilities. Heinkel arranged a meeting between his engineers and Ohain, during which he argued that the current "garage engine" would never work, but that the concept upon which it was based was sound. The engineers were convinced, and in April Ohain and Hahn began working for Heinkel at the Marienehe airfield outside Rostock, in Warnemünde.

A study of the model's airflow resulted in several improvements over a two-month period. Encouraged by these findings, Ohain produced a new prototype that would run on hydrogen gas supplied by an external pressurised source. The resulting Heinkel-Strahltriebwerk 1 (HeS 1), German for Heinkel Jet Engine 1, was built by hand-picking some of the best machinists in the company, much to the chagrin of the shop-floor supervisors. Hahn, meanwhile, worked on the combustion problem, an area in which he had some experience.

The engine was extremely simple, made largely of sheet metal. Construction started late in the summer of 1936 and was completed in March 1937. Two weeks later the engine was running on hydrogen, but the high temperature exhaust led to considerable "burning" of the metal. The tests were otherwise successful, and in September the combustors were replaced and the engine was run on gasoline for the first time. Ohain had at last, albeit five months after Frank Whittle, working in parallel in England, run a self-contained turbojet. Running on gasoline proved to clog up the combustors, so Hahn designed a new version based on his soldering torch, which proved to work much better. Although the engine was never intended to be a flight-quality design, it proved beyond a doubt that the basic concept was workable, and Ohain had at last caught up with Whittle. With vastly more funding and industry support, Ohain would soon overtake Whittle and forge ahead.

While work on the HeS 1 continued, the Pohl-Ohain team had already moved on to the design of a flight-quality engine, the HeS 3. The major differences were the use of machined compressor and turbine stages, replacing the bent and folded sheet metal, and a re-arrangement of the layout to reduce the cross-sectional area of the engine as a whole by placing the flame cans in an extended gap between the compressor and turbine. The original design proved to have a turbine area that was simply too small to work efficiently, and increasing the size of the turbine meant the flame cans would no longer fit into the gap correctly.

A new design, the HeS 3b was proposed, which moved the flame cans out of the gap and modified their shape to allow the widest part of the cans to lie in front of the compressor's outer rim. In the HES 3b, compressed air was piped forward to the combustion chambers, and from there the hot air flowed rearward into the turbine inlet. While not as small as the original HeS 3 design, the 3b was nevertheless fairly compact. The 3b first ran in July 1939 (some references say in May), and was air-tested under the Heinkel He 118 dive bomber prototype. The original 3b engine soon burned out, but a second one was nearing completion at about the same time as a new test airframe, the Heinkel He 178, which first flew on 27 August 1939, the first jet-powered aircraft to fly by test pilot Erich Warsitz.

Work started immediately on larger versions, first the HeS 6 which was simply a larger HeS 3b, and then on a new design known as the HeS 8 which once again re-arranged the overall layout. The 8 separated the compressor and turbine, connecting them with a long shaft, placing a single annular combustion chamber between them, replacing the individual flame cans. It was intended to install the engine on the Heinkel He 280 fighter, but the airframe development progressed much more smoothly than the engine, and had to be used in gliding tests while work on the engine continued. A flight-quality HeS 8 was installed in late March 1941, followed by the first flight on 2 April. Three days later the aircraft was demonstrated for a party of Nazi and RLM officials, all of whom were impressed. Full development funds soon followed.

By this point there were a number of turbojet developments taking place in Germany. Heinkel was so impressed by the concept that he arranged the transfer to the project of Adolph Müller from Junkers, who was developing an axial compressor-powered design, renamed as the Heinkel HeS 30. Müller left Junkers after they purchased the Junkers Motoren company, who had their own project under way, which by this time was known as the Junkers Jumo 004. Meanwhile, BMW was making good progress with its own design, the BMW 003.

By early 1942 the HeS 8, officially the 109-001 (HeS 001), was still not progressing well. Meanwhile, Müller's HeS 30, officially the 109-006 (HeS 006), was developing much more quickly. Both engines were still some time from being ready for production, however, while the 003 and 004 appeared to be ready to go. In early 1942 the director of jet development at the RLM, Helmut Schelp, refused further funding for both designs, and ordered Heinkel to work on a new "pet project" of his own, eventually becoming the Heinkel HeS 011. Although this was the first of Schelp's "Class II" engines to start working well, production had still not started when the war ended. Work continued on the HeS 8 for some time, but it was eventually abandoned in the spring of 1943.

It has long been claimed that Ohain was unaware of Whittle's work. While in a very strict sense this may be true - (in that he was unaware of Whittle's experiments at Lutterworth where the RAF engineer ran the world's first jet engine in March 1937), nevertheless Ohain had thoroughly studied Whittle's various patents for gas turbine engines, as is normal professional practice for any academic working in a similar field, prior to filing his own patent which was registered in 1935, some five years after Whittle's. In his biography, Ohain frankly critiqued Whittle's design:

"When I saw Whittle's patent I was almost convinced that it had something to do with boundary layer suction combinations. It had a two-flow, dual entrance flow radial flow compressor that looked monstrous from an engine point of view. Its flow reversal looked to us to be an undesirable thing, but it turned out that it wasn't so bad after all though it gave some minor instability problems ... Our patent claims had to be narrowed in comparison to Whittle's because Whittle showed certain things." He then somewhat understandably justified their knowledge of Whittle's work by saying "We felt that it looked like a patent of an idea" "We thought that it was not seriously being worked on."

Post-WWII

In 1947, Ohain was brought to the United States by Operation Paperclip and went to work for the United States Air Force at Wright-Patterson Air Force Base. In 1956 he was made the Director of the Air Force Aeronautical Research Laboratory and by 1975 he was the Chief Scientist of the Aero Propulsion Laboratory there.

During his work at Wright-Patterson, Ohain continued his own personal work on various topics. In the early 1960s he did a fair amount of work on the design of gas core reactor rockets which would retain the nuclear fuel while allowing the working mass to be used as exhaust. The engineering needed for this role was also used for a variety of other "down to earth" purposes, including centrifuges and pumps. Ohain would later use the basic mass-flow techniques of these designs to create a fascinating jet engine with no moving parts, in which the airflow through the engine created a stable vortex that acted as the compressor and turbine.

This interest in mass-flow led Ohain to research magnetohydrodynamics (MHD) for power generation, noting that the hot gases from a coal-fired plant could be used to extract power from their speed when exiting the combustion chamber, remaining hot enough to then power a conventional steam turbine. Thus an MHD generator could extract further power from the coal, and lead to greater efficiencies. Unfortunately this design has proven difficult to build due to a lack of proper materials, namely high-temperature non-magnetic materials that are also able to withstand the chemically active exhaust. Ohain also investigated other power related concepts.

He also invented the idea of the "jet wing", in which air from the compressor of a jet engine is bled off to large "augmented" vents in the wings to provide lift for VTOL aircraft. A small amount of high-pressure air is blown into a venturi, which in turn sucks a much larger volume of air along with it, thus leading to "thrust augmentation". The concept was used in the Rockwell XFV-12 experimental aircraft, although the market interest in VTOL aircraft was short-lived. He participated in several other patents.

Ohain was the influence in shifting the mind of Paul Bevilaqua, one of his students at WP-AFB, from math to engineering, which later enabled Bevilaqua to invent the Rolls-Royce LiftSystem for the JSF F35B STOVL: "in school I learned how to move the pieces, and Hans taught me how to play chess". Ohain also showed Bevilaqua "what those TS-diagrams actually mean".

During his career, Ohain won many engineering and management awards, including (among others) the American Institute of Aeronautics and Astronautics (AIAA) Goddard Astronautics Award, the United States Air Force Exceptional Civilian Service Award, Systems Command Award for Exceptional Civilian Service, the Eugene M. Zuckert Management Award, the Air Force Special Achievement Award, and just before he retired, the Citation of Honor. In 1984–85, Ohain served as the Charles A. Lindbergh Chair in Aerospace History, a competitive senior fellowship at the National Air and Space Museum. In 1991 Ohain and Whittle were jointly awarded the Charles Stark Draper Prize for their work on turbojet engines. Ohain was elected a member of the U.S. National Academy of Engineering (NAE).

Awards

e retired from Wright-Patterson in 1979 and took up an associate professor position at the nearby University of Dayton. Ohain was awarded the Ludwig-Prandtl-Ring from the Deutsche Gesellschaft für Luft- und Raumfahrt (German Society for Aeronautics and Astronautics) for "outstanding contribution in the field of aerospace engineering" in 1992.

Death

Ohain later moved to Melbourne, Florida, with his wife Hanny, where he died in 1998, aged 86. He was survived by four children.

— — — = = — — —

This text is available under the Creative Commons Attribution-ShareAlike License
Source : Article Hans von Ohain of Wikipedia ( authors )
Hans Joachim Pabst von Ohain : Your comments on this subject
Powered by Disqus
Top
Legal Credits FAQ Help Site Map

Terms of use for the services available on this site

By using this Website, Users agree to the following terms of use and rules :

Definitions

  • Webmaster : Head Administrator with all authority over the management and development of the Website.
  • Administrator : Anyone that was given by the Webmaster full or partial access to the Website's structure or with moderation rights on messages posted by Users.
  • User or Visitor : Any person visiting the Website pages.
  • Website : The following provisions apply to a single Website accessible via the www.aircraftube.com, www.aircraftube.org, www.aircraftube.net and www.all-aircraft.com. URL's
  • Service : All free informations and tools contained on the Website.
  • Comments : All text written by users on Blogs and comment pages available on the Website.
  • Media : All media available on or through the Website. One must distinguish the local media (photos, curves, drawings) and the external media (videos) which the Website refers.

    • Purpose of this site

    The purpose of this non-commercial site is purely educational. Reflecting a passion, it is also there to preserve the memory of all those who gave their lives, their health or energy in the name of freedom, aviation safety or simply our passenger comfort.

    Copyright

    Some media may have escaped the vigilance of Administrators with regard to copyrights. If a user reports copyright infringement, he will be asked to prove that he is indeed the rights's owner for the concerned media. If so, his decision on the Administrator's next action will be respected: A total suppression of the Media on the Website, or the addition of some owner's reference. The publication of a media on the internet normally having as a goal to make it visible to many people, the Administrators expect in any case that the second option will be most often chosen.

    Pursuant to the Law on copyright and related rights, the user has the right to download and reproduce information on the Website for personal use and provided that the source is mentionned. They cannot however be used for commercial or advertising purposes.

    Using Blogs and filing comments

  • Moderator : The Administrator reserves the right to prevent the publication of comments that are not directly related to the Service without providing any explanation. Similarly, all insults, out of scope or unethical material will be banned.
  • Identification : Persons wishing to post a comment or use any form of contact are required to provide identification by the means of a valid e-mail address.
  • Responsibilities : Comments are posted on the Website under the unique responsability of their authors and the Administrators may in no case be liable for any statements or claims that the users might have issued.

    • As the comment system is hosted and maintained on servers external to the Website, the Administrators may in no circumstances be held responsible for the use that administrators of these servers or other third parties may have with those comments or filed data.

    Content Liability

    The Administrators carefully check the reliability of the sources used. They cannot, however, guarantee the accuracy of any information contained on the Website, partly because of the multiple sources from which they come.

    JavaScript and cookies - Storing information

    This Website imperatively uses JavaScript and cookies to function properly. Neither of these technologies, or other means shall in no case be used on the Website for the retention or disclosure of personal information about Visitors. Exceptions to this rule will involve storing the Users banned for inappropriate comments they might have given as well as contact information for Users wishing to subscribe to future newsletters.

    When a user accesses the Website, the corresponding servers may automatically collect certain data, such as IP address, date and time of Website access, viewed pages and the type of browser used. This information is kept only for the purpose of measuring the number of visitors to the different sections of the site and make improvements.

    Donations - Advertising

    To continue providing the Service for free, the Webmaster reserves the right to insert advertising or promotional messages on any page of the Site. In the same idea, any donations will only by used to cover the running costs of the site, such as hosting, connection fees, hardware and software necessary for the development and maintenance of the Website.

    Links and other websites

    Administrators shall in no case be liable for the non-availability of websites operated by third parties to which users would access through the Website.

    Administrators assume no liability for any content, advertising, products and/or services available on such third party websites. It is reminded that those sites are governed by their own terms of use.

    Placing a link to third party sites or authorize a third party to include a link on their website refering to this Website does not mean that the Administrators recommend in any way the products or services offered by these websites.

    Modifications

    The Webmaster reserves the right to modify at any time without notification the present terms of use as well as all content or specific functionality that the Website offers.

    The modified terms and conditions immediately apply to the using Visitor when changes come online. Visitors are invited to consult the site regularly on the most current version of the terms and conditions

    Governing Law and Jurisdiction

    These general conditions are governed by Belgian law.

    In case of dispute regarding the interpretation and/or execution of the above terms, the parties agree that the courts of the district of Nivelles, Belgium shall have exclusive jurisdiction power.

    Credits page

    Wikipedia.org

    Wikipedia is a collaboratively edited, multilingual, free Internet encyclopedia.

    Youtube

    YouTube is a video-sharing website on which users can upload, view and share videos.

    Special thanks to all Youtube quality aviation vids providers, specially (Those I forgot, please excuse me or report) :

    Airboyd
    Andys Video
    Aviation videos archives
    Bomberguy
    Classic Aviation TV
    Historical Aviation Film Unit
    Horsemoney
    Jaglavaksoldier
    Joluqa Malta
    Just Planes
    Koksy
    Classic Airliners & Vintage Pop Culture
    Memorial Flight
    Octane130
    Okrajoe
    SDASM archives
    Spottydog4477
    The Aviators TV
    Valentin Izagirre Bengoetxea
    Vexed123
    VonBerlich
    Zenos Warbirds

    Bundesarchiv

    The German Federal Archives or Bundesarchiv are the National Archives of Germany.

    FAQ

    I don't see my comments any more!

    Please note that each page has it's own comment entry. So, if you enter a comment i.e. on the B-747, you will only see it on that related page.

    General comments are accessed via the "BLOG En" button.

    Comments are moderated, so please allow some delay before they appear, specially if you are outside Europe.

    Menus are developing below the page, because they are too long!

    But they remain accessible, for example by scrolling the mouse wheel, or with your finger (on the menu) on a smartphone or tablet.

    I see adds on all videos.

    Use a good free add remover software.

    The site is loading random pages at startup.

    We think it is a good way to bring back the memory of aircraft, persons or events sometimes quite forgotten.

    HELP PAGE

    Why this site?

    Discovery

    This website is dedicated to one's aeronautical passion (which I hope we share) and was realised mainly as an educationnal tool. Knowing that, you'll notice that each new visit brings random topics for the purpose of making new discoveries, some achievements or characters certainly not deserving the oblivion into which they have sometimes fallen.

    By these pages, we also want to pay tribute to all those who gave at one time or another, their lives or health in the name of freedom, aeronautical security or simply our comfort.

    Centralisation

    Internet is full of websites dedicated to aviation, but most are dedicated to subjects or periods that are very limited in space or time. The purpose of this site is to be as general as possible and thus treats all events as well as characters of all stripes and times while putting much emphasis on the most significant achievements.

    The same years saw birth of technologies like photography and cinema, thus permitting illustration of a large part of important aeronautical events from the start. Countless (and sometimes rare) media recently put online by enthousiasts finally give us access to these treasures, but the huge amount of information often makes things a little messy. A centralization effort is obviously most needed at this level.

    All persons who directly or indirectly contributed to the achievement or posting of such documents are here gratefully acknowledged.

    General

    Fluid website

    This site automatically fits the dimensions of your screen, whether you are on a desktop computer, a tablet or a smartphone.

    Bilingual website

    You can change the language by clicking on the flag in the upper left or via "Options" in the central menu. Of course, the videos remain in the language in which they were posted ...

    Browser compatibility

    The site is not optimized, or even designed to run on older browsers or those deliberately deviating from standards. You will most probably encounter display issues with Internet Explorer. In this case, it is strongly recommended installing a modern (and free!) browser that's respecting the standards, like Firefox, Opera, Chrome or Safari.

    Cookies and Javascript

    This site uses cookies and JavaScript to function properly. Please ensure that your browser is configured accordingly. Neither of these technologies, or other means shall in no case be used on the Site for the retention or disclosure of personal information about its Visitors. See the "Legal" page for more on this subject.

    Website layout

    Left menus

    Because of the lack of space on smartphones and small tablets, these menus are hidden. Everything is nevertheless accessible via the main menu option, located between the video and photo sections. This menu is placed there for compatibility reasons with some browsers, which play the videos over the menus.

    "Search" and "Latest" :
    The link "In Titles" restricts the search to the titles of different forms. Use this option if you are looking for a plane, a constructor, a pilot or a particular event that could have been treated as a subject.

    The link "In Stories" will bring you to a search in all texts (the "Story" tab) and will take more time. The search term will appear highlighted in green when opening the corresponding story.

    Would you believe, "Timeline" will show all subjects in chronological order.

    "Random" will reload the entire page with a new random topic.

    The bottom section keeps you abreast of the latest five entries. New topics are added regularly. Don't hesitate to come visit us often : add bookmark.

    Blogs and Comments central section

    Under the photos section comes the comments tabs window :

    You can enter general comments in your own language via one of the two buttons on the left (BLOG EN and BLOG FR). Note that these buttons are accessible regardless of the language to allow some participation in the other language.

    All comments are subject to moderation and will be published only if they comply with the basic rules of decorum, while remaining relevant to the purpose of this site.

    The third tab allows you to enter comments on the shown topic and is bilingual. Personal anecdotes, supplements and other information questions will take place here.

    The "Story" tab shows the explanatory texts. They are most often taken from Wikipedia, a site where we participate regularly.

    The "Data" tab is reserved for list of features and specifications.

    Right menus

    On a smartphone, the lack of space is growing and this menu is moved to the bottom of the page to give priority to videos and pictures.

    The top right icons are links to videos posted by third parties (on their own responsabilities) or by ourselves. The link below these icons will take you to the channel of the one who posted the video. Feel free to suggest other videos if you think they are of some interest (Use the BLOG button or the "Contact" link).