CF6 turbofan at the KLM engine shop

The General Electric TF39 and CF6 are a family of high-bypass turbofan engines. A turbofan is a type of Jet engine, similar to a Turbojet. It essentially consists of a Ducted fan with a smaller diameter turbojet engine Originally developed as the TF39 to power the C-5 Galaxy, they were the first high-power high-bypass jet engines available, and went on to power a wide variety of civilian airliners. WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout Their primary competition is the Rolls-Royce RB211, and derivatives of both engine designs power almost every widebody airliner currently flying. The Rolls-Royce RB211 is a family of high-bypass Turbofan engines made by Rolls-Royce plc and capable of generating 37400 to 60600 pounds-force (166 The basic engine core also forms the basis for the LM2500, LM5000 and LM6000 marine and power generation turboshafts. The General Electric LM2500 industrial and marine Turboshaft Gas turbine is a derivative of GE Aircraft Engines ' CF6-6 aircraft engine The General Electric LM6000 is a Turboshaft Gas turbine. The LM6000 is derived from the CF6-80C2 Aircraft Turbofan A turboshaft engine is a form of Gas turbine which is optimized to produce Shaft power, rather than Jet thrust. GE-Aviation intends to replace the CF6 family with the GEnx, which are expected to enter service in 2008. GE Aviation, a subsidiary of General Electric, is headquartered in Evendale Ohio (a Cincinnati suburb WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout This is a list of Aviation -related events from 2008: Events January January 2 – Asian Spirit Flight

History

GE CF6 high-bypass turbofan

The United States Air Force opened the "CX-X Program" in 1964, intending to produce a next-generation strategic airlifter. A cargo aircraft (also known as freighters or freight aircraft) is an Fixed-wing aircraft designed or converted for the carriage of goods rather Of the several airframe and engine proposals returned for consideration, in 1965 Lockheed's aircraft design and General Electric's engine design were selected for the new design.

The high-bypass turbofan was a huge leap in engine performance, offering high thrust of 43,000 pounds, while improving fuel efficiency by about 25%. ^[1] The TF39 had an 8-to-1 bypass ratio, 25-to-1 compressor pressure ratio, a 2,500 °F (1,370 °C) turbine temperature made possible by advanced forced-air cooling. The first engine went for testing in 1965. Between 1968 and 1971, 463 TF39-1 and -1A engines were produced and delivered to power the C-5A fleet.

The engine was then offered for civilian use as the CF6, and quickly found interest in two designs being offered for a recent Eastern Airlines contract, the Lockheed L-1011 and McDonnell Douglas DC-10. Eastern Air Lines was a major United States Airline that existed from the late 1920s until 1991 WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout Although the L-1011 would eventually select the RB211, thus creating the CF6's greatest competitor, the DC-10 stuck with the CF6 and made it a success in this market as well when it started flying in 1971. It was also selected for versions of the Boeing 747, which was a development of Boeing's unsuccessful entry for the CX-X. WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout Since then the CF6 has powered versions of the Airbus A300, 310 and 330, Boeing 767, and McDonnell Douglas MD-11. WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout ^[2]

Variants

TF39

The TF39 is a revolutionary 1960s engine rated from 41,000 to 43,000 lb_f (191 to 205 kN) of thrust. The 1960s decade refers to the years from the beginning of 1960 to the end of 1969 This article deals with the unit of force For the unit of mass see Pound (mass. The newton (symbol N) is the SI derived unit of Force, named after Isaac Newton in recognition of his work on Classical It employed a great deal of then-new technological features such as:

• 1½ stage fan blades (unique to TF39).
• 8:1 bypass ratio. Description Jet engines are generally able to create considerably more energy than they can use in moving air through the engine core
• Variable stator vanes.
• Turbines equipped with advanced cooling.
• Fuel efficiency better than any engines available at the time.
• Cascade-type thrust reversers. Thrust reversal, also called reverse thrust, is the temporary diversion of an Aircraft engine 's exhaust or changing of propeller pitch so that the thrust produced

Mechanically, the TF39 is rather unusual for a high bypass ratio turbofan; the single stage snubbered^[a] fan rotor has a set of inlet guide vanes for the outer bypass section and the core booster stage is located in front of the fan rotor, rather than behind. The following sectional view shows the fan arrangement of the TF39 (http://www.aircraftenginedesign.com/pictures/TF39.gif). Note the very long gas generator used in this pioneering design.

CF6-6

An FAA cutaway diagram of the CF6-6 engine

The CF6-6 was a development of the military TF39. The Federal Aviation Administration ( FAA) is an agency of the United States Department of Transportation with authority to regulate and oversee all aspects of It was first utilized on the McDonnell Douglas DC-10-10. McDonnell Douglas was a major American Aerospace manufacturer and Defense contractor, producing a number of famous commercial and military aircraft

This initial version of the CF6 comprises a single stage fan, with one core booster stage, driven by a 5-stage LP (low pressure) turbine, supercharging a 16-stage HP (high pressure) axial compressor driven by a 2-stage HP turbine; the combustor is annular and exhaust separate jets. Axial compressors are rotating aerofoil based compressors in which the working fluid principally flows parallel to the axis of rotation A combustor is a component or area of a Gas turbine, Ramjet or Pulsejet The 86. 4 in (2. 19 m) diameter fan generates an airflow of 1300 lb/s (590 kg/s), resulting in a relatively high bypass ratio of 5. 72. The overall pressure ratio of the compression system is 24. In Aeronautical engineering, the term overall pressure ratio is defined as the ratio of the Stagnation pressure as measured at the front and rear of the compressor 3. At maximum take-off weight, the engine develops a static thrust of 40,000 lb_f (178 kN).

A complete disintegration of a CF6-6 fan assembly resulted in the loss of cabin pressurization of National Airlines Flight 27 over New Mexico, USA in 1973. Cabin pressurization is the active pumping of compressed Air into an Aircraft cabin when flying at altitude to maintain a safe and comfortable environment for crew This article describes an accident to National Airlines Flight 27 in 1973 New Mexico ( is a state located in the southwestern region of the United States of America. The United States of America —commonly referred to as the This is a list of Aviation -related events from 1973: Events Icelandair established ^[3] The failure of a CF6-6 resulted in the Sioux City, Iowa USA crash of United Airlines Flight 232 in 1989. Sioux City (ˌsuːˈsɪti is a city located in northwest Iowa in the United States. United Airlines Flight 232 was a scheduled flight operated by United Airlines between Denver and Philadelphia via Chicago. This is a list of Aviation -related events from 1989: Events January January 4 - US Navy F-14 Tomcats

CF6-50

The CF6-50 series are high-bypass turbofan engines rated between 46,000 and 54,000 lb_f (205 to 240 kN) of thrust. The CF6-50 was developed into the LM2500 industrial and marine turboshaft engines. A turboshaft engine is a form of Gas turbine which is optimized to produce Shaft power, rather than Jet thrust. It was launched in 1969 to power the long range McDonnell Douglas DC-10-30, and was derived from the earlier CF6-6. This is a list of Aviation -related events from 1969: Events The Canadian Snowbirds Aerobatic team is formed

Because a significant increase in thrust and therefore core power was required not long after the -6 had entered service, General Electric could not increase (HP) turbine rotor inlet temperature significantly, so they took the very expensive decision to reconfigure the CF6 core to increase its basic size. They achieved this by removing two stages from the rear of the HP compressor (even leaving an empty air passage, where the blades and vanes had once been located). two extra booster stages were added to the IP (intermediate pressure) compressor, which increased the overall pressure ratio to 29. 3. Although the 86. 4 in (2. 19 m) diameter fan was retained, the airflow was raised to 1450 lb/s (660 kg/s), yielding a static thrust of 51,000 lb_f (227 kN). The increase in core size and overall pressure ratio, significantly raised the core flow, resulting in a decrease in bypass ratio to 4. 26.

In late 1969, the CF6-50 was selected to power the then new Airbus A300. Airbus SAS (ˈɛərbʌs in English, Airbus2ogg|/ɛʁbys/]] in French, and /ˈɛːɐbʊs/ in German) is an aircraft manufacturing WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout Air France became the launch customer for the A300 by ordering six aircraft in 1971. Air France (formally Société Air France) is one of the world's largest Airlines Air France is based in Paris, France, and is a subsidiary of This is a list of Aviation -related events from 1971: Events January January 6 - the United States Marine Corps In 1975, KLM was the first airline to order the Boeing 747 powered by the CF6-50. This is a list of Aviation -related events from 1975: Events January A specially modified McDonnell Douglas F-15 Eagle KLM Royal Dutch Airlines ( Dutch: Koninklijke Luchtvaart Maatschappij, literally Royal Aviation Company; usual English translation Boeing Commercial Airplanes is a unit of The Boeing Company, based in Renton, Washington consisting of the Seattle -based former Boeing WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout This led further developments to the CF6 family such as the CF6-80.

CF6-80

The CF6-80 series are high-bypass turbofan engines with a thrust range of 48,000 to 75,000 lb_f (214 to 334 kN). It is an advanced development of the earlier successful CF6-50 series engine, but despite superficial resemblance, it is a completely new engine with no interchangeable parts. Although the HP compressor still has 14 stages, GE did take the opportunity to tidy-up the design, by removing the empty air passage at compressor exit.

Following a series of high-pressure turbine failures,^{[4] [5] [6]} some which resulted in 767s being written off,^{[7] [8] [9]} the FAA has issued an airworthiness directive mandating inspections for over 600 engines. The Federal Aviation Administration ( FAA) is an agency of the United States Department of Transportation with authority to regulate and oversee all aspects of The NTSB feels this number should be increased to include all -80 series engines with more than 3000 cycles since new or since last inspection. The National Transportation Safety Board (NTSB is an independent U ^[10]

The -80 series is divided into three distinct models.

CF6-80A

The CF6-80A, which has a thrust rating of 48,000 to 50,000 lb_f (214 to 222 kN), powered two twinjets, the Boeing 767 and Airbus A310. WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout The GE-powered 767 entered airline service in 1982, and the GE powered A310 in early 1983. This is a list of Aviation -related events from 1982: Events January January 8 - the Airbus A300 is certified This is a list of Aviation -related events from 1983: Events January January 1 - Eastern Air Lines ' first revenue It is rated for ETOPS operations.

For the CF6-80A/A1, the fan diameter remains at 86. 4 in (2. 19 m), with an airflow of 1435 lb/s (651 kg/s). Overall pressure ratio is 28. 0, with a bypass ratio of 4. 66. Static thrust is 48,000 lb_f (214 kN). The basic mechanical configuration is the same as the -50 series.

CF6-80C2

A Delta Air Lines Boeing 767-400ER with CF6-80C2 engines

The CF6-80C2, which entered revenue service in October 1985, has a thrust rating of 52,500 to 63,500 lb_f (234 to 282 kN). Delta Air Lines Inc ( is a United States Airline based and headquartered in Atlanta, Georgia. WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout This is a list of Aviation -related events from 1985: Events Ryanair founded initially as a full-service carrier It has a reputation of good fuel economy in its thrust class. The CF6-80C2 is certified with 16 different thrust ratings. This versatile engine has the most widespread use of any large turbofan engine.

For the CF6-80C2-A1, the fan diameter is increased to 93 in (2. 36 m), with an airflow of 1750 lb/s (790 kg/s). Overall pressure ratio is 30. 4, with a bypass ratio of 5. 15. Static thrust is 59,000 lb_f (263 kN). An extra stage is added to the HP compressor, and a 5th to the LP turbine.

The CF6-80C2 is currently certified on eleven wide-body aircraft models including the Boeing 747 and McDonnell Douglas MD-11. wide-body aircraft is a large Airliner with twin aisles and typically a fuselage diameter of 5 to 6 metres (16 to 20 ft WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout The CF6-80C2 is also certified for ETOPS-180 for the A300, A310, Boeing 767 aircraft and the U.S. Air Force's C-5M Super Galaxy. WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout

CF6-80E1

The CF6-80E1 is specifically designed for the Airbus A330, with thrust rating of 67,500 to 72,000 lb_f (300 to 334 kN). WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout For the CF6-80E1A2, the fan diameter is increased to 96 in (2. 44 m), with an airflow of 873,6 kg/s 1925 lb/s (875 kg/s). Overall pressure ratio is 32. 6, with a bypass ratio of 5. 3.

Other variants

The industrial and marine development of the CF6-80C2, the LM6000 Series, has found wide use including fast ferry and high speed cargo ship applications, as well as in power generation. The General Electric LM6000 is a Turboshaft Gas turbine. The LM6000 is derived from the CF6-80C2 Aircraft Turbofan Unlike the LM2500 and LM5000, it is capable of cold (compressor) end drive allowing for an axial exhaust which aids power output and efficiency. The LM6000 actually uses the LP compressor section from the CF6-50.

CF6-32

The CF6-32 was intended to be a stripped-down version of the CF6-80 for the Boeing 757. WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout It was never launched due to lack of interest from airlines.

Applications

• TF39
  • Lockheed C-5A/B/C Galaxy
• CF6-6
  • McDonnell Douglas DC-10-10
• CF6-50
  • McDonnell Douglas DC-10-30
  • Boeing 747-200/-300
  • Airbus A300
  • McDonnell Douglas KC-10 Extender
  • Boeing E-4B NAOC
• CF6-80
  • Boeing 747-400/-400ER
  • Boeing VC-25 (Air Force One), the only CF6-80 application on 747-200s
  • Boeing 767
    • Boeing E-10 MC2A
    • Boeing E-767 AWACS
    • Boeing KC-767
  • Lockheed C-5M Galaxy
  • McDonnell Douglas MD-11
  • McDonnell Douglas MD-12 (Never built)
  • Airbus A300
  • Airbus A310
  • Airbus A330
  • Kawasaki C-X

References

Notes

External links

• GE CF6 website
• Volvo Aero CF6-80 webpage subcontractor
• NTSB Safety Recommendation on GE CF-6 engines of December 12 2000 PDF 262 KB
• Stammen, Ken. "Engine failures cause GE overhaul", The Cincinnati Post, 2001-01-03. The Cincinnati Post is a discontinued afternoon daily newspaper that was published in Cincinnati Ohio. Year 2001 ( MMI) was a Common year starting on Monday according to the Gregorian calendar. Events 1431 - Joan of Arc is handed over to the Bishop Pierre Cauchon. Archived from the original on 2007-08-22. Year 2007 ( MMVII) was a Common year starting on Monday of the Gregorian calendar in the 21st century. Events 392 - Arbogast has Eugenius elected Western Roman Emperor.