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35-482: The AL-21 is closely similar in technology to the General Electric J79 first flown in 1955, which was the first engine for supersonic flight, using a variable stator. It is generally described as being in the "third generation" of Soviet gas turbine engines which are characterized by high thrust-to-weight ratios and the use of turbine air cooling. The AL-21 entered service in the early 1960s. Later designed

70-607: A chance meeting with W. Langhorne Bond of the China National Aviation Corporation (CNAC). The company arranged for Neumann to enter China without a passport. He flew to Kunming , capital of the remote Yunnan province, and there he contacted the Chinese Air Force. He worked as an auto mechanic until the Pearl Harbor attack , when he accepted an offer from Colonel Claire Lee Chennault , who had established

105-413: A compressor with a wide speed-range of operation". An experimental 12-stage compressor was built with the inlet guide vanes and first four rows of stator blades adjustable to lower the air incidence angles while running at low speed. It was very effective in overcoming the stall and surge. However, a simpler mechanical-design solution (variable inlet guide vanes and bleed) had already been shown to work with

140-623: A disadvantage in combat aircraft making them vulnerable to visual detection. Later models were redesigned to be "smokeless". The turboshaft counterpart to the J79 is the General Electric LM1500, used for land and marine applications. Many J79-derived engines have found uses as gas turbine power generators in remote locations, in applications such as powering pipelines. The J79 has two commercial derivatives: CJ805 -3 (a non-afterburning engine, fitted with thrust reverser and sound suppressor), and

175-628: A journey of many thousands of miles on poor roads by Jeep , Neumann, Clarice and their dog Mr. Chips arrived in Tel Aviv during the first Arab-Israeli war and were able to travel conventionally to New York City . In March 1948, Neumann began work as a test engineer for the General Electric Aircraft Gas Turbine Division, located in Lynn, Massachusetts . There he drove many innovations in jet engine design, which included promoting

210-566: A new supersonic bomber, which became the Convair B-58 Hustler . The two other engines offered by GE, an advanced version of the existing J73 and a much larger design, known as the J77, were both cancelled. The first prototype of the production version, XJ-79, ran on 8 June 1954. The first flight of the engine was on 20 May 1955 with the engine installed in a General Electric J47 -powered North American B-45C Tornado ( serial 48-009 ) . In flight

245-495: A single Sud Aviation Caravelle intended to demonstrate to the U.S. market the benefits of a bypass engine over the existing Rolls-Royce Avon turbojet. In 1959 the gas generator of the J79 was developed as a stationary 10MW-class (13,000 bhp) free-turbine turboshaft engine for naval power, power generation, and industrial use, called the LM1500 . Its first application was in the research hydrofoil USS  Plainview . By

280-539: The AL-21F3 , it was used in the Sukhoi Su-17 , Sukhoi Su-24 , Ground-attack variant Mikoyan-Gurevich MiG-23 , and Sukhoi T-10 ( Sukhoi Su-27 prototype). Related lists General Electric J79 The General Electric J79 is an axial-flow turbojet engine built for use in a variety of fighter and bomber aircraft and a supersonic cruise missile . The J79 was produced by General Electric Aircraft Engines in

315-781: The CJ805 -23 (with a free-wheeling aft fan and thrust reverser) fitted to the Convair CV-880 and the Convair CV-990 respectively. J79 engines may be started using compressed air directly on the engine turbine blades or by using a turbine starter attached to the accessory gearbox. The gas used in this starter is either compressed air or from a solid propellant cartridge. Data from Jane's All The World's Aircraft, J79 - Turbine Engines: A Closer Look Related development Comparable engines Related lists Gerhard Neumann Gerhard Neumann (October 8, 1917 – November 2, 1997)

350-636: The F-111 and F-14 , and newer generation turbofans with the Pratt & Whitney F100 used in the F-15 Eagle which give better cruise fuel efficiency by-passing air around the core of the engine. For their part in designing the J79, Gerhard Neumann and Neil Burgess of General Electric Aircraft Engines were jointly awarded the Collier Trophy in 1958, also sharing the honor with Clarence Johnson (Lockheed F-104) and

385-585: The United Kingdom declared war on Germany, and all Germans in Hong Kong were rounded up and interned in La Salle College , Kowloon, a Christian Brothers High School for boys. Neumann was interned in the school together with some 100 Germans for several months. The British in Hong Kong considered any German citizen a potential fifth column and revoked his passport. No embassy would talk to him. Neumann had

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420-486: The Aircraft Gas Turbine Division lead, C.W. 'Jim' LaPierre, formed two teams to do design studies for an engine that could run for extended periods at Mach 2.0 while still giving good fuel economy while cruising at Mach 0.9. Neumann led a team using a variable stator configuration, while Chapman Walker led a parallel effort using two-spools. After a years study the engine with variable stators was chosen as it

455-684: The Chinese Air Force with Madame Chiang Kai-shek , to work in support of that Air Force. As the war with Japan progressed, the Chinese Air Force became the American Volunteer Group (AVG), nicknamed the " Flying Tigers ." Neumann was part of the Headquarters Squadron as a Propeller Specialist. While with the Flying Tigers, Neumann was nicknamed "Herman the German". When the AVG was replaced by

490-901: The Communist People's Liberation Army was taking over China. The Neumanns had no choice but to attempt to return to the United States. They chose an unusual route. Instead of flying or sailing across the Pacific, Clarice suggested that they drive over the Asian continent towards North Africa. Thus began their incredible and quite dangerous journey to the Mediterranean Sea, via Siam (now Thailand), Burma, India, Afghanistan, Iraq, and Palestine. Most border crossings were dangerous, because by 1948 most countries in Asia were undergoing political turmoil. Finally, after

525-493: The J79 was lowered from the bomb bay into the airstream for testing. The first flight after the 50-hour qualification test, required for a new engine that is the sole source of thrust for a flying testbed, was on 8 December 1955, powering the second pre-production Douglas F4D Skyray , with the J79 in place of its original Westinghouse J40 engine as part of the General Electric development and qualification program. The YF-104

560-568: The U.S. Army Air Forces, Neumann was inducted into the USAAF in July 1942 although he was not yet a U.S. citizen. He helped the effort against the Japanese in many important ways. He led dangerous supply convoys, performed all types of mechanical repairs on P-40 aircraft, translated to and from Chinese, assembled a working enemy Zero fighter from crash parts to assess its flight characteristics (the other such Zero

595-636: The US Air Force (Flight Records). The compressor blades and vanes are made of 403 stainless steel , except for the -3B and -7A variants, which have A286 vanes at stages 7 through 17. The compressor rotor is made of Lapelloy, B5F5 and titanium. The J79 makes a particular howling sound at certain throttle settings. This strange feature led to the NASA operated F-104B Starfighter, N819NA , being named Howling Howland . Early engines also produced noticeable quantities of smoke, especially at mid-throttle/cruise settings,

630-585: The US, and under license in Belgium, Canada, Germany, Israel, Italy, and Japan. A downgraded version of the General Dynamics F-16 Fighting Falcon with a J79 was proposed as a low-cost fighter for export, and though a prototype aircraft was flown, it found no customers. The J79 was replaced by the late 1960s in new fighter designs by afterburning turbofans such as the Pratt & Whitney TF30 used in

665-571: The United States, and under license by several other companies worldwide. Among its major uses was the Lockheed F-104 Starfighter , Convair B-58 Hustler , McDonnell Douglas F-4 Phantom II , North American A-5 Vigilante and IAI Kfir . A commercial version, designated the CJ805 , powered the Convair 880 , while an aft-turbofan derivative, the CJ805-23, powered the Convair 990 airliners and

700-437: The best way of designing the compressor for the high required pressure ratio of 12:1. This pressure ratio was needed to achieve the supersonic performance, subsonic cruise performance and low weight necessary for future supersonic aircraft. In 1951, a General Electric team led by Gerhard Neumann , at that time in charge of engine development testing, was given funding to build a test compressor with variable stators. In addition,

735-519: The college, he learned to construct and pilot a one-person glider. His experience as an engine mechanic, aircraft designer, and practical engineer proved very useful in his career. The winds of war were growing in Nazi Germany , and alliances were murky and shifting. In late 1938, Neumann saw a bulletin board posting at Mittweida saying that Chinese Generalissimo Chiang Kai-shek needed engineers in his fight against Japanese invaders . Engineers who got

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770-512: The design speed. Departures of velocity from the design condition are most noticeable in the first stages at low rpm and become more so as the design pressure ratio is increased leading to blade stall and compressor surging as happened with the Rolls-Royce Avon compressor, with design pressure ratio of 6.3:1 in 1949. In 1947 Geoff Wilde , a Rolls-Royce compressor designer, had applied for a patent "Axial flow compressor regulation" "to provide

805-540: The jobs would receive deferment from conscription into the German army. Neumann decided to leave his family and embark on a long journey to the British colony of Hong Kong in May 1939. But upon arriving in Hong Kong, he found that the company for which he was to work had disappeared. Fortunately, his skills as an auto mechanic were in great demand. A few months later, on 1 September 1939, Germany invaded Poland . On 3 September,

840-474: The late 1940s, jet engine design had progressed to the point where further progress was limited by the performance of its compressor, in particular the pressure ratio of the compressor had to be increased to reduce the engine fuel consumption. However, the useful operating range of the compressor was limited at that time and centered around its design condition which is at a high compressor speed for take-off or cruise. If designed for high efficiency at high speeds it

875-430: The required design pressure ratio so variable stators were not used in a Rolls-Royce engine until the 1980s ( IAE V2500 ). By 1950 General Electric was focussing on supersonic engines with variable stators as a result of design studies which compared them with dual-rotor types. Based on their past experience at that time, and estimation of the development effort required to prove new technologies, variable stators promised

910-554: The variable stator compressor for the J79 jet engine which enabled aircraft such as the F-104 to reach speeds of Mach 2 ; The development team (Neumann, Neil Burgess, and Clarence L. Johnson of Lockheed) were awarded the Collier Trophy for 1958. As a Vice President at General Electric, he piloted various jet fighters during the 1960s to personally understand how engines behaved in flight and what pilots required from them. A major success for GE

945-472: The war, he was finally permitted to work for Douglas Aircraft Research. In late 1946, Chennault offered Neumann an engineering position with Chinese National Relief and Rehabilitation Airline, a new airline Chennault was forming using war-surplus C-46 transports. Neumann accepted, and on their way to China he and Clarice were married. In the year that followed, the Chinese Civil War was raging and

980-567: Was a German-American aviation engineer and executive for General Electric 's aircraft engine division (which today is called GE Aerospace ). Born and raised in Germany, he went to China shortly before World War II where he became an aircraft mechanic for the United States Army Air Forces . He was naturalised as an American citizen by an Act of Congress, and went on to a career in the aerospace manufacturing industry. Neumann

1015-576: Was born in Frankfurt (Oder) in the Prussian Province of Brandenburg . His parents Siegfried and Frieda were non-practicing Jewish Germans . As a teenager, Neumann apprenticed under a master auto mechanic, surnamed Schroth, who followed the traditional Prussian lifestyle of "First the work, then the pleasure." In 1935, Neumann entered the well-regarded technical college Ingenieurschule Mittweida and earned very high grades. With other students from

1050-554: Was his guiding the design and development of the huge high-bypass turbofan jet engines (or simply called "fanjets") that now power the largest commercial and military cargo aircraft. These include the TF39 , CF6 , and (in 50/50 collaboration with SNECMA ) the CFM56 . Neumann retired from GE on January 1, 1980, after 32 years of service. He remained active in retirement, until he developed leukemia and died on November 2, 1997. In 1987, Neumann

1085-792: Was inducted into the National Aviation Hall of Fame in Dayton, Ohio. The Gerhard Neumann Museum in Niederalteich , Bavaria , honors his contributions to aviation. The Massachusetts Institute of Technology Aeronautics and Astronautic Department's Neumann Hangar facility in Cambridge, Massachusetts, is named in his honor. His autobiography "Herman the German: Just Lucky I Guess" chronicles his life. GE Aerospace, located in Evendale, Ohio,

Lyulka AL-21 - Misplaced Pages Continue

1120-613: Was lighter, simpler and had a smaller diameter. A demonstrator engine with variable stators, the GOL-1590, predecessor to the J79 was built. At the same time a new engine, the X-24A, was designed for a supersonic aircraft and selected by the Air Force. Development of the new engine was supported by running the GOL-1590 demonstrator engine. GE won the Air Force contract for a new engine with approximately 14,000 pounds thrust, with afterburning, to power

1155-630: Was the Akutan Zero ), and even directed bombing attacks from the ground while disguised as a Chinese coolie . Eventually Neumann was dispatched to Washington, D.C. to brief William Donovan, head of the OSS, where he met his future wife Clarice. Yet for all of Neumann's heroism in China, as a German he was still considered an enemy alien . It took an act of the United States Congress to correct this. After

1190-593: Was the next airplane to fly with the J79 followed by a re-engined Grumman F11F Tiger in a Navy-sponsored program to gain experience with the engine before the first flight of the F4H (F-4). The J79 was used on the F-104 Starfighter, B-58 Hustler, F-4 Phantom II, A-5 Vigilante, IAI Kfir aircraft and the SSM-N-9 Regulus II supersonic cruise missile. It was produced for more than 30 years. Over 17,000 J79s were built in

1225-502: Was very inefficient and prone to stall at low speeds. In 1944 the National Advisory Committee for Aeronautics had tested a theory for "Extending the useful operating range of axial-flow compressors by use of adjustable stator blades" by running an eight-stage axial compressor with pressure ratio 3.42:1 and adjustable blade angles. Considerable improvement in efficiencies were obtained at compressor speeds appreciably below

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