General Electric CF6
The General Electric CF6 series is a widely used jet engine in the medium thrust class from the US manufacturer General Electric . The original model TF39 was the first turbofan engine with a high bypass ratio .
The CF6 is based on the military model TF39 . This is the first engine design from General Electric that enabled a high bypass ratio of up to 8: 1 and thus significantly reduced fuel consumption compared to older models. Ultimately, a total of 463 units of the TF39 in the versions TF39-1 and -1A were produced between 1968 and 1971 and delivered to operate the C-5A fleet.
The engine to be redesigned was to be used with the new generation of wide-body aircraft that were to serve high-frequency medium-haul routes. The models initially considered for this were the McDonnell Douglas DC-10 and the Lockheed L-1011 . Competitors from General Electric (GE), Rolls-Royce and Pratt & Whitney also applied to equip these models with their respective engine designs. The two main operators of the DC-10 (Series 10) in the USA, United Airlines and American Airlines , decided after tests in the spring of 1968 for the model CF6-6 from GE, which at the time had a thrust of around 190 kN .
The second model, the Lockheed L-1011, on the other hand, was awarded to Rolls-Royce , who equipped this aircraft with their RB211 . The market was thus divided. The Lockheeds were exclusively equipped with RB211 during their entire time in service; For future aircraft types a distribution battle broke out between the CF6 and the RB211, which basically continues to this day.
The routes to be mastered became longer and the aircraft heavier, so both more powerful and more fuel-efficient engines were needed. This led to the development of the CF6-50 version in 1969, which could be offered with a thrust range of 205 to 240 kN and which was used on the long-range version of the DC-10 baptized "Series 30".
A new arena for the competition for the initial equipment was the tender for a model from a completely new manufacturer: The Airbus company , a pan-European consortium, developed its first aircraft, the Airbus A300 . The current CF6-50 version won the tender from the first customer Air France , and GE was allowed to equip the prototype of the A300 and the six following models for Air France in 1971. This decision opened up a very large market for the CF6. Rolls-Royce had no luck with the A300 when the British government withdrew from the Airbus project (it did not rejoin until 1979), and so the newly emerging market, which from 1982 also included the A310 , was between the CF6-80C2A (214 –222 kN) and the Pratt & Whitney models .
An originally unfortunate decision by GE not to participate in the tender for the Boeing 747 was later compensated for by a clever strategy. In 1973 , when the US Air Force bid for a new airborne guidance system, the Boeing E-4 based on the B747 , the CF6 found its way into Boeing's top model. The increasing cost pressure due to rising oil prices ( oil crisis 1973) forced many airlines to pay attention to more interoperability. Those airlines that operated the DC-10 and A300 in their fleets were now able to order their B747s with CF6 engines and were thus able to save maintenance costs.
In competition with the new Airbus models, Boeing developed the 767 model for medium- haul routes with high passenger volumes. GE responded and constructed the CF6-80C2B1, which was also available for order for the B767 from the start. With this aircraft type, all three major manufacturers came together, everyone was able to secure a market share here. In addition to the CF6-80C2B1, the Boeing 767 also flies with the RB211-524 from Rolls-Royce and the PW4062 from Pratt & Whitney . The same applied to the B747-400, which could also be ordered with the three previously mentioned engine types. In addition, GE has launched various versions of the CF6-80C2, such as the CF6-80C2B7F, where the "F" in the nomenclature stands for FADEC .
The CF6 has been continuously developed, which can also be determined from an almost unmanageable number of sub-versions (e.g. CF6-80E1A4). The latest version has been certified for the Airbus A330 , which has been in service for Air France since 2002. As a successor to the CF6, General Electric has been developing the GEnx since 2004, which first went into service on the Boeing 747-8 .
The CF6 series is still a great success today. The engine has been in service since 1969, has been sold to over 200 customers with more than 2,400 commercial aircraft and to date has completed more flight hours than any other wide-body aircraft engine.
The CF6 essentially shares the market with two competitors. The Rolls-Royce RB211 is just as successful as the CF6. It is used competitively on Boeing 767-300 and 747-400. Above all, the Boeing 757 , which has not been produced since 2005 , was a great success for the Rolls-Royce RB211-535. Around 600 models of this type are currently flying with the Rolls-Royce engines mentioned, which are also considered to be extremely reliable. With newer aircraft types, such as the Airbus A330 , Rolls-Royce is currently and will be a competitor to the CF6 with the models of the Trent 700 series .
The second competitor is Pratt & Whitney, who initially offered their Pratt & Whitney JT9D in competition with the CF6, for example for the first A310 models. This manufacturer later developed the PW4000 series. It has been further developed in a similar way to the GE CF6 series. Today it has a similarly wide range of applications, which includes the types A300-600, A310-300, A330, B747-400, B767-200, B767-300ER, B777 and the MD-11.
- CF6-6: approx. 191 kN
- CF6-50: 205–240 kN (long-haul version for A300, DC10 and B747)
- CF6-80: 214-310 kN (completely revised version)
- CF6-80A: 214-222 kN
- CF6-80C2: 234–282 kN (larger fan diameter, improved compressor and optimized high-pressure turbine)
- CF6-80E1: 293-310 kN (again enlarged fan, higher compression)
Common aircraft types
- McDonnell Douglas DC-10 (CF6-6 or CF6-50)
- McDonnell Douglas MD-11 (CF6-80C2D1F)
Airbus A300 (CF6-50; early models)
- Airbus A300-600 (CF6-80C2)
- Airbus A300-600 ST (CF6-80C2A8; Beluga)
Airbus A310 (CF6-80C2)
- Airbus A310-304 (CF6-80C2A2)
- Airbus A310-308 (CF6-80C2A8)
Airbus A330-200 (CF6-80E1)
- Airbus A330-300 (CF6-80E1, CF6-80E1A4B)
Boeing 767 (CF6-80A; early models)
- Boeing 767-200 (CF6-80C2B4F)
- Boeing 767-300 (CF6-80C2B4F)
- Boeing 767-400ER (CF6-80C2B8F)
Boeing 747 (CF6-45A2, CF6-50E2; early models)
- Boeing 747-300 (CF6-80C2B1)
- Boeing 747-400 (CF6-80C2B1F, early models)
- Boeing 747-400 (CF6-80C2B5F, CF6-80C2B8F)
- Lockheed C5M (CF6-80C2L1F)
The CF6 is also used on the military versions of the above. civil aircraft, such as E-4, KC-10, B767 tankers, B767 AWACS, A310 MRTT and A330 multirole tankers. Outside of aviation, it is used in the LM2500, LM5000 and LM6000 series as a stationary gas turbine as a drive for ferries, frigates , fast cargo ships or electrical generators.
|Type of compressor||Axial fan|
|Type of turbine||Axially|
|Type of combustion chambers||Annular combustion chamber|
|Number of fan levels||1|
|Number of low pressure compressor stages||1||3||4th||4th|
|Number of high pressure compressor stages||16||14th|
|Number of high pressure turbine stages||2|
|Number of low pressure turbine stages||5||4th||5|
|Number of waves||2|
|Engine length||4775 mm||4648 mm||4267 mm||4278 mm|
|Engine diameter||2667 mm||2667 mm||2692 mm||2899 mm|
|Dry weight||4080 kg||4104 kg||4472 kg||5092 kg|
|thrust||185 kN||224-240 kN||233-282 kN||282-305 kN|
|Bypass ratio||5.92: 1||4.4: 1||5.31: 1||5.1: 1|
|Compression ratio||25: 1||30: 1||32: 1||35: 1|
|Air flow||approx. 600 kg / s||approx. 780 kg / s|
|Fuel consumption||approx. 2.3 kg / s||approx. 2.7 kg / s|
- Manufacturer information on the CF6 series
- Type Certificate of the CF6-80E1 series - EASA-TCDS-E.007 (PDF; 214 kB) accessed on June 6, 2015