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30-698: The YJ93 started life as the General Electric J79-X275, an enlarged version of the General Electric J79 turbojet with "275" meaning Mach 2.75, the engine's target operating speed. This design evolved into the X279 when Mach 3 cruise became a requirement, and ultimately became the YJ93. The engine used a special high-temperature JP-6 fuel. The six YJ93 engines in the XB-70 Valkyrie were capable of producing

60-413: 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

90-623: 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

120-566: 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

150-663: A supersonic cruise missile . The J79 was produced by General Electric Aircraft Engines in 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,

180-509: A thrust to weight ratio of 5:1 allowing for a speed of 2,000 mph (3,200 km/h) (approximately Mach 3) at an altitude of 70,000 feet (21,000 m). The first engine went on test in September 1958 and featured advanced technology achievements such as electrolytically drilling longitudinal air cooling holes in the turbine blades. The XF-108 interceptor was cancelled outright, and the B-70 project

210-764: Is a two-shaft high-bypass turbofan engine built by International Aero Engines (IAE) which powers the Airbus A320 family , the McDonnell Douglas MD-90 , and the Embraer C-390 Millennium . The engine's name is a combination of the Roman numeral V, symbolizing the five original members of the International Aero Engines consortium, which was formed in 1983 to produce the V2500 engine. The 2500 represents

240-606: 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 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

270-425: The Airbus A320 than the competing CFM56-5A; however, initial reliability issues, coupled with insufficient thrust for the larger A321, prompted the development of the improved V2500-A5 variant. It first entered service with Cyprus Airways . A fourth booster stage was introduced into the engine basic configuration to increase core flow. This, together with a minor fan diameter and airflow increase, helped to increase

300-682: 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 IAE V2500 The IAE V2500

330-636: 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

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360-517: The LM1500 . Its first application was in the research hydrofoil USS  Plainview . 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

390-511: The -A5 configuration, as well as two variants with significant increase in thrust, thus expanding the thrust range from 23,500 lbf to 33,000 lbf: On October 10, 2005, IAE announced the launch of the V2500Select—later called V2500SelectOne—with a sale to IndiGo Airlines to power 100 A320 series aircraft. The V2500SelectOne is a combination performance improvement package and aftermarket agreement. In February 2009, Pratt & Whitney upgraded

420-582: The 25,000- pound-force (110 kN) produced by the original engine model, the V2500-A1. FAA type certification for the V2500 was granted in 1988. The maintenance, repair, and operations market for the V2500 is close to US$ 3 billion as of 2015. Rolls-Royce based the 10-stage HP compressor on an 8-stage run in the RB401 in the mid 1970's followed by a 9-stage run in the RJ.500 . The V.2500 would use 10 stages, with

450-486: 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

480-453: The CJ805-23, powered the Convair 990 airliners and 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

510-493: 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

540-636: 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,

570-585: 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

600-437: 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,

630-533: The configuration of the V2500-A5, but is fitted with different mounting hardware and accessory gearboxes to facilitate installation on the McDonnell Douglas MD-90 . This engine retains the configuration of the V2500-A5, but is fitted with different mounting hardware and accessory gearboxes to facilitate installation on the Embraer KC-390 . A number of de-rated, Stage 4 noise compliant engines have been produced from

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660-512: 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

690-437: The first 4 with variable stators, giving a pressure ratio of 20:1. A single-stage booster was also part of the original configuration. Serious handling problems (inability to accelerate without surging) with this arrangement resulted in a redesigned compression system. The pressure ratio was reduced to 16:1 which needed a fifth variable stage and revised blading in the rear stages. Two extra booster stages were required to restore

720-560: The maximum thrust to 33,000 lbf (147 kN) thrust, to meet the requirements of the larger Airbus A321 . Soon, Airbus offered derated versions of the V2500-A5 on the Airbus A319 and Airbus A320 , enabling the same engine hardware to be used across all Airbus A320 family aircraft, with the exception of the Airbus A318 . The vast majority of V2500s are of the A5 variety. This engine retains

750-530: The original overall pressure ratio. A fourth booster stage would be added after the initial variant entered service. Pratt & Whitney developed the combustor and the 2-stage air-cooled HP turbine, while the Japanese Aero Engine Corporation provided the LP compression system. MTU Aero Engines were responsible for the 5-stage LP turbine and Fiat Avio designed the gearbox. In 1989, its unit cost

780-430: 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

810-721: Was US$ 4.7 million. The 4,000th V2500 was delivered in August 2009 to the Brazilian flag carrier TAM and installed on the 4,000th Airbus A320 family aircraft, an A319. In early 2012, the 5,000th V2500 engine was delivered to SilkAir, and IAE achieved 100 million flying hours. Six years later, in June 2018, over 7,600 engines were delivered and the V2500 achieved 200 million flight hours on 3,100 aircraft in service. The original version, has 1 fan stage, 3 LP booster stages, 10 HPC stages, 2 HPT stages, and 5 LPT stages. This engine promised better fuel burn on

840-613: 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

870-449: Was re-oriented to a research project only. Data from Aircraft engines of the World 1966/77, Military Turbojet/Turbofan Specifications, North American XB-70A Valkyrie Related development Comparable engines 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

900-593: 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

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