The General Electric J79 is an

axial-flow An axial compressor is a gas compressor that can continuously pressurize gases. It is a rotating, airfoil-based compressor in which the gas or working fluid principally flows parallel to the axis of rotation, or axially. This differs from other ...

turbojet The turbojet is an airbreathing jet engine which is typically used in aircraft. It consists of a gas turbine with a propelling nozzle. The gas turbine has an air inlet which includes inlet guide vanes, a compressor, a combustion chamber, a ...

engine built for use in a variety of fighter and

bomber aircraft A bomber is a military combat aircraft designed to attack ground and naval targets by dropping air-to-ground weaponry (such as bombs), launching torpedoes, or deploying air-launched cruise missiles. The first use of bombs dropped from an air ...

and a supersonic

cruise missile A cruise missile is a guided missile used against terrestrial or naval targets that remains in the atmosphere and flies the major portion of its flight path at approximately constant speed. Cruise missiles are designed to deliver a large warh ...

. The J79 was produced by

General Electric Aircraft Engines A general officer is an officer of high rank in the armies, and in some nations' air forces, space forces, and marines or naval infantry. In some usages the term "general officer" refers to a rank above colonel."general, adj. and n.". OED On ...

in the United States, and under license by several other companies worldwide. Among its major uses was the

F-104 Starfighter The Lockheed F-104 Starfighter is an American single-engine, supersonic air superiority fighter which was extensively deployed as a fighter-bomber during the Cold War. Created as a day fighter by Lockheed as one of the " Century Series" of ...

B-58 Hustler The Convair B-58 Hustler, designed and produced by American aircraft manufacturer Convair, was the first operational bomber capable of Mach 2 flight. The B-58 was developed during the 1950s for the United States Air Force (USAF) Strategic Air ...

F-4 Phantom II The McDonnell Douglas F-4 Phantom II is an American tandem two-seat, twin-engine, all-weather, long-range supersonic jet interceptor and fighter-bomber originally developed by McDonnell Aircraft for the United States Navy.Swanborough and ...

A-5 Vigilante The North American A-5 Vigilante was an American carrier-based supersonic bomber designed and built by North American Aviation (NAA) for the United States Navy. Prior to 1962 unification of Navy and Air Force designations, it was designated t ...

and

IAI Kfir , abbreviated , is a Japanese martial art that emphasizes being aware and capable of quickly drawing the sword and responding to sudden attacks.Christensen, Karen and Allen Guttmann et.al (2001) ''International Encyclopedia of Women and Sport ...

. A commercial version, designated the CJ805, powered the

Convair 880 The Convair 880 is an American narrow-body jet airliner produced by the Convair division of General Dynamics. It was designed to compete with the Boeing 707 and Douglas DC-8 by being smaller but faster, a niche that failed to create demand. Wh ...

, while an aft-turbofan derivative, the CJ805-23, powered the

Convair 990 The Convair 990 Coronado is an American narrow-body four-engined jet airliner produced between 1961 and 1963 by the Convair division of American company General Dynamics. It was a stretched version of its earlier Convair 880 produced in respo ...

airliner An airliner is a type of aircraft for transporting passengers and air cargo. Such aircraft are most often operated by airlines. Although the definition of an airliner can vary from country to country, an airliner is typically defined as an ai ...

s and a single

Sud Aviation Caravelle The Sud Aviation SE 210 Caravelle is a French jet airliner produced by Sud Aviation. It was developed by SNCASE in the early 1950s and made its maiden flight on 27 May 1955. It included some de Havilland designs and components developed f ...

intended to demonstrate to the U.S. market the benefits of a bypass engine over the existing Avon turbojet. In 1959 the gas generator of the J79 was developed as a stationary 10MW-class () free-turbine turboshaft engine for naval power, power generation, and industrial use, called the LM1500. Its first application was in the research

hydrofoil A hydrofoil is a lifting surface, or foil, that operates in water. They are similar in appearance and purpose to aerofoils used by aeroplanes. Boats that use hydrofoil technology are also simply termed hydrofoils. As a hydrofoil craft gains s ...

Development

Evolution of the variable stator compressor

By 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 was very inefficient and prone to stall at low speeds. In 1944 the

National Advisory Committee for Aeronautics The National Advisory Committee for Aeronautics (NACA) was a United States federal agency founded on March 3, 1915, to undertake, promote, and institutionalize aeronautical research. On October 1, 1958, the agency was dissolved and its assets ...

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 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 The Rolls-Royce Avon was the first axial flow jet engine designed and produced by Rolls-Royce. Introduced in 1950, the engine went on to become one of their most successful post-World War II engine designs. It was used in a wide variety of ...

compressor, with design pressure ratio of 6.3:1 in 1949. In 1947

Geoff Wilde Geoffrey Light Wilde (21 May 1917 – 18 August 2007) was a British engineer employed by Rolls-Royce Limited. Early life Geoffrey Light Wilde was born in Warwickshire. He was first educated in France, where his father Alfred was working. His f ...

, a Rolls-Royce compressor designer, had applied for a patent "Axial flow compressor regulation" "to provide 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 the required design pressure ratio so variable stators were not used in a Rolls-Royce engine until the 1980s (V2500). By 1950

General Electric General Electric Company (GE) is an American multinational conglomerate founded in 1892, and incorporated in New York state and headquartered in Boston. The company operated in sectors including healthcare, aviation, power, renewable ene ...

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 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

team led by

Gerhard Neumann Gerhard Neumann (October 8, 1917 – November 2, 1997) was an American aviation engineer and executive for General Electric's aircraft engine division (which today is called GE Aviation). Born and raised in Germany, he went to China shortly be ...

, at that time in charge of engine development testing, was given funding to build a test compressor with variable stators. In addition, 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 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.

General

GE won the Air Force contract for a new engine with approximately 14,000 pounds thrust, with afterburning, to power a new supersonic bomber, which became the

Convair B-58 Hustler The Convair B-58 Hustler, designed and produced by American aircraft manufacturer Convair, was the first operational bomber capable of Mach 2 flight. The B-58 was developed during the 1950s for the United States Air Force (USAF) Strategic Air ...

. 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

J47 The General Electric J47 turbojet (GE company designation TG-190) was developed by General Electric from its earlier J35. It first flew in May 1948. The J47 was the first axial-flow turbojet approved for commercial use in the United States. I ...

-powered B-45C ''(48-009)''. In flight 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 The Douglas F4D Skyray (later redesignated F-6 Skyray) is an American carrier-based fighter/ interceptor built by the Douglas Aircraft Company. Although it was in service for a relatively short time (1956–1964) and never entered combat, it w ...

, with the J79 in place of its original Westinghouse J40 engine as part of the General Electric development and qualification program. The YF-104 was the next airplane to fly with the J79 followed by a re-engined

Grumman F11F Tiger The Grumman F11F/F-11 Tiger is a supersonic, single-seat carrier-based United States Navy fighter aircraft in operation during the 1950s and 1960s. Originally designated the F11F Tiger in April 1955 under the pre-1962 Navy designation system, i ...

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

and

SSM-N-9 Regulus II The SSM-N-9 Regulus II cruise missile is a supersonic guided missile armed with a nuclear warhead, intended for launching from surface ships and submarines of the U.S. Navy (USN).Koch, Charles A"Regulus II cruise missile".''Regulus II Cruise Missi ...

supersonic cruise missile. It was produced for more than 30 years. Over 17,000 J79s were built in the US, and under license in Belgium, Canada, Germany, Israel, Italy, and Japan. A downgraded version of the

F-16 Fighting Falcon The General Dynamics F-16 Fighting Falcon is a single-engine multirole fighter aircraft originally developed by General Dynamics for the United States Air Force (USAF). Designed as an air superiority day fighter, it evolved into a successf ...

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 The Pratt & Whitney TF30 (company designation JTF10A) is a military low-bypass turbofan engine originally designed by Pratt & Whitney for the subsonic F6D Missileer fleet defense fighter, but this project was cancelled. It was later adapted with ...

used in the

F-111 The General Dynamics F-111 Aardvark is a retired supersonic, medium-range, multirole combat aircraft. Production variants of the F-111 had roles that included ground attack (e.g. interdiction), strategic bombing (including nuclear weapons ca ...

and F-14, and newer generation

turbofan The turbofan or fanjet is a type of airbreathing jet engine that is widely used in aircraft engine, aircraft propulsion. The word "turbofan" is a portmanteau of "turbine" and "fan": the ''turbo'' portion refers to a gas turbine engine which ac ...

s with the

Pratt & Whitney F100 The Pratt & Whitney F100 (company designation JTF22) is an afterburning turbofan engine manufactured by Pratt & Whitney that powers the F-15 Eagle and F-16 Fighting Falcon. Development In 1967, the United States Navy and United States Air Forc ...

used in the

F-15 Eagle The McDonnell Douglas F-15 Eagle is an American Twinjet, twin-engine, all-weather Air combat manoeuvring#Tactics, tactical fighter aircraft designed by McDonnell Douglas (now part of Boeing). Following reviews of proposals, the United States ...

which give better cruise

fuel efficiency Fuel efficiency is a form of thermal efficiency, meaning the ratio of effort to result of a process that converts chemical potential energy contained in a carrier (fuel) into kinetic energy or work. Overall fuel efficiency may vary per device ...

by-passing air around the core of the engine. For their part in designing the J79,

and Neil Burgess of General Electric Aircraft Engines were jointly awarded the

Collier Trophy The Robert J. Collier Trophy is an annual aviation award administered by the U.S. National Aeronautic Association (NAA), presented to those who have made "the greatest achievement in aeronautics or astronautics in America, with respect to ...

in 1958, also sharing the honor with

Clarence Johnson Clarence Leonard "Kelly" Johnson (February 27, 1910 – December 21, 1990) was an American aeronautical and systems engineer. He is recognized for his contributions to a series of important aircraft designs, most notably the Lockheed U-2 an ...

(Lockheed F-104) and the US Air Force (Flight Records).

Design

The compressor blades and vanes are made of 403

stainless steel Stainless steel is an alloy of iron that is resistant to rusting and corrosion. It contains at least 11% chromium and may contain elements such as carbon, other nonmetals and metals to obtain other desired properties. Stainless steel's r ...

, 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 The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research. NASA was established in 1958, succeedin ...

operated F-104B Starfighter, ''N819NA'', being named ''Howling Howland''.Bashow 1986, p. 16. Early engines also produced noticeable quantities of smoke, especially at mid-throttle/cruise settings, a disadvantage in combat aircraft making them vulnerable to visual detection. Later models were redesigned to be "smokeless". The

turboshaft A turboshaft engine is a form of gas turbine that is optimized to produce shaftpower rather than jet thrust. In concept, turboshaft engines are very similar to turbojets, with additional turbine expansion to extract heat energy from the exhaust ...

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 the CJ805-23 (with a free-wheeling aft fan and thrust reverser) fitted to the

Convair CV-880 The Convair 880 is an American narrow-body jet airliner produced by the Convair division of General Dynamics. It was designed to compete with the Boeing 707 and Douglas DC-8 by being smaller but faster, a niche that failed to create demand. When ...

and the

Convair CV-990 The Convair 990 Coronado is an American narrow-body four-engined jet airliner produced between 1961 and 1963 by the Convair division of American company General Dynamics. It was a stretched version of its earlier Convair 880 produced in respon ...

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.

Variants

;XJ79-GE-1 :Prototype. First ground static test run on 8 June 1954 produced with afterburner. ;YJ79-GE-1 :Flight test engines were designated YJ79-GE-1. ;J79-GE-2 :Powered the

McDonnell F-4H-1 Phantom The McDonnell Douglas F-4 Phantom II is an American tandem two-seat, twin-engine, all-weather, long-range supersonic jet interceptor and fighter-bomber originally developed by McDonnell Aircraft for the United States Navy.Swanborough and Bowe ...

(F-4A), of afterburner thrust. ;J79-GE-2A :essentially similar to the -2 ;J79-GE-3 :Used in the YF-104A, F-104A and the

Grumman F11F-1F Super Tiger The Grumman F11F-1F Super Tiger (company designation G-98J) is a single-seat fighter aircraft originally developed for the United States Navy (USN). Based on the USN's F-11 Tiger, the F11F-1F did not proceed beyond the two F11F-1F prototypes. D ...

;J79-GE-3A :YF-104A, F-104A and F-104B. ;J79-GE-3B :F-104A and F-104B. ;J79-GE-5A :

with afterburner. ;J79-GE-5B :

with afterburner. ;J79-GE-5C J79

;J79-GE-7 :F-104C, F-104D and F-104F. ;J79-GE-7A :F-104C, F-104D and F-104F. :;J79-OEL-7 ::Licensed production GE-7 manufactured by

Orenda Engines Orenda Engines was a Canadian aircraft engine manufacturer and parts supplier. As part of the earlier Avro Canada conglomerate, which became Hawker Siddeley Canada, they produced a number of military jet engines from the 1950s through the 1970s, ...

to power the

Canadair CF-104 The Canadair CF-104 Starfighter (CF-111, CL-90) is a modified version of the Lockheed F-104 Starfighter supersonic fighter aircraft built in Canada by Canadair under licence. It was primarily used as a ground attack aircraft, despite being des ...

. ;J79-GE-8:

North American A-5 Vigilante The North American A-5 Vigilante was an American carrier-based supersonic bomber designed and built by North American Aviation (NAA) for the United States Navy. Prior to 1962 unification of Navy and Air Force designations, it was designated t ...

and F4H-1 (F-4B) with 16,950 lbf (75.4 kN) of afterburner thrust ;J79-GE-8A :Sub-variant of the -8 ;J79-GE-8B :Sub-variant of the -8 ;J79-GE-10 :F-4J, 17,900 lbf (79.379 kN) of afterburner thrust. ;J79-GE-11 : ;J79-GE-11A :German F-104G and TF-104G. Pakistani

Griffin The griffin, griffon, or gryphon ( Ancient Greek: , ''gryps''; Classical Latin: ''grȳps'' or ''grȳpus''; Late and Medieval Latin: ''gryphes'', ''grypho'' etc.; Old French: ''griffon'') is a legendary creature with the body, tail, and ...

F-104A and F-104B. 15,600 lbf (69 kN) with afterburner. Many -11 engines were licensed manufactured in

Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a Continent#Subcontinents, subcontinent of Eurasia ...

as part of the large F-104

consortium A consortium (plural: consortia) is an association of two or more individuals, companies, organizations or governments (or any combination of these entities) with the objective of participating in a common activity or pooling their resources ...

production programme,

Alfa Romeo Alfa Romeo Automobiles S.p.A. () is an Italian luxury car manufacturer and a subsidiary of Stellantis. The company was founded on 24 June 1910, in Milan, Italy. "Alfa" is an acronym of its founding name, "Anonima Lombarda Fabbrica Automobili." "A ...

Fiat Fiat Automobiles S.p.A. (, , ; originally FIAT, it, Fabbrica Italiana Automobili di Torino, lit=Italian Automobiles Factory of Turin) is an Italian automobile manufacturer, formerly part of Fiat Chrysler Automobiles, and since 2021 a subsidiar ...

and

Fabrique Nationale Fabrique Nationale Herstal (), trading as FN Herstal and often referred to as Fabrique Nationale or simply FN, is a leading firearms manufacturer based in Herstal, Belgium. It is currently the largest exporter of military small arms in Europe. ...

being the main suppliers for the project. :;J79-IHI-11A ::Licensed production GE-11A, built in

Japan Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the n ...

Ishikawajima-Harima Heavy Industries Co., Ltd , formerly known as , is a Japanese engineering corporation headquartered in Tokyo, Japan that produces and offers ships, space launch vehicles, aircraft engines, marine diesel engines, gas turbines, gas engines, railway systems, turbochargers ...

to power their similarly licensed built F-104J and F-104DJ Starfighters. :;J79-MTU-J1K ::Licensed built and improved version of the GE-11A manufactured by

MTU Aero Engines MTU Aero Engines AG is a German aircraft engine manufacturer. MTU develops, manufactures and provides service support for military and civil aircraft engines. MTU Aero Engines was formerly known as MTU München. History While the Munich-based en ...

Germany Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated betwee ...

. ;J79-GE-15 :F-4C, RF-4C, F-4D; with 17,000 lbf (75.6kN) of afterburner thrust. ;J79-GE-17 :F-4E, RF-4E, F-4EJ, F-4F, F-4G; with of afterburner thrust. ;J79-GE-19 :

Aeritalia F-104S The Aeritalia F-104S Starfighter was a licensed production Italian version of the Lockheed F-104 Starfighter, which served in the Italian Air Force, and was its mainstay from the late 1960s until the beginning of the 21st century. The F-104S als ...

; also retrofitted to F-104A's of the 319th FIS. ;J79-GE-J1E :License-built in

Israel Israel (; he, יִשְׂרָאֵל, ; ar, إِسْرَائِيل, ), officially the State of Israel ( he, מְדִינַת יִשְׂרָאֵל, label=none, translit=Medīnat Yīsrāʾēl; ), is a country in Western Asia. It is situated ...

Beit Shemesh Engines Ltd. Beit Shemesh ( he, בֵּית שֶׁמֶשׁ ) is a city located approximately west of Jerusalem in Israel's Jerusalem District, with a population of in . History Tel Beit Shemesh The small archaeological tell northeast of the modern city wa ...

(BSEL) with afterburning thrust for the

. ;J79-GE-119 :F-16/79

Applications

;Aircraft *

* General Dynamics F-16/79 *

Lockheed F-104 Starfighter The Lockheed F-104 Starfighter is an American single-engine, supersonic air superiority fighter which was extensively deployed as a fighter-bomber during the Cold War. Created as a day fighter by Lockheed as one of the "Century Series" of fi ...

McDonnell Douglas F-4 Phantom II The McDonnell Douglas F-4 Phantom II is an American tandem two-seat, twin-engine, all-weather, long-range supersonic jet interceptor and fighter-bomber originally developed by McDonnell Aircraft for the United States Navy.Swanborough and B ...

Northrop X-21 The Northrop X-21A was an experimental aircraft designed to test wings with laminar flow control. It was based on the Douglas WB-66D airframe, with the wing-mounted engines moved to the rear fuselage and making space for air compressors. The airc ...

* SSM-N-9/RGM-15 Regulus II ;Land speed record cars * Art Arfons' "Green Monster" *

Craig Breedlove Craig Breedlove (born March 23, 1937) is an American professional race car driver and a five-time world land speed record holder. He was the first person in history to reach , and , using several turbojet-powered vehicles, all named '' Spirit o ...

's "Spirit of America - Sonic 1" *

North American Eagle Project The North American Eagle Project was a jet powered car that was intended to challenge the (Mach 1.02) land speed record set by the ThrustSSC in 1997. The venture was a collaboration between Canadian and US engineers, pilots, and mechanics. In 20 ...

Specifications (J79-GE-17)

References

Notes

Bibliography

* * Pace, Steve. ''Lockheed F-104 Starfighter''. Osceola, Wisconsin: Motorbooks International, 1992. . * Bashow, David L. ''Starfighter: A Loving Retrospective of the CF-104 Era in Canadian Fighter Aviation, 1961–1986''. Stoney Creek, Ontario: Fortress Publications Inc., 1990. . * Gunston, Bill. ''Fighters of the Fifties''. Cambridge, England. Patrick Stephens Limited, 1981. . * Williams, Nick and Steve Ginter "Douglas F4D Skyray". Simi Valley, California: Ginter, 1986. .

External links

General Electric Aviation, J79 page

Animation of J79 turbojet (German language)
{{USAF system codes J79 1950s turbojet engines