General Electric CF6

The General Electric CF6, US military designations F103 and F138, is a family of high-bypass turbofan engines produced by GE Aviation. The CF6, based on the TF39, the first high-thrust, high-bypass jet engine, has been used in a wide variety of airliners, but has been superseded by the GEnx in newer airliners.

The CF6 core has been used for the LM2500, LM5000, and LM6000 industrial and marine gas turbines.

After developing the TF39 for the C-5 Galaxy in the late 1960s, GE offered a higher thrust variant for civilian use, the CF6. GE proposed the CF6 to Eastern Airlines, for the Lockheed L-1011 and the McDonnell Douglas DC-10. Lockheed used the Rolls-Royce RB211 as its exclusive engine, but the CF6 was chosen for the DC-10, and entered service in 1971. It was also selected for versions of the Boeing 747, and then for the Airbus A300, A310 and A330, Boeing 767, Lockheed C-5M Galaxy, and McDonnell Douglas MD-11.

By 2018, GE had delivered more than 8,300 CF6s: 480 -6s, 2,200 -50s, 4,400 -80C2s, more than 730 -80E; and 3,000 LM6000 industrial and marine derivatives. The in-service fleet included 3,400 engines, generating over 600 shop visits per year.

The CF6-6 was first used on the McDonnell Douglas DC-10-10.

It has a single-stage fan with one core booster stage driven by a 5-stage LP (low pressure) turbine, and a 16-stage HP (high pressure) axial compressor driven by a 2-stage HP turbine; the combustor is annular; separate exhaust nozzles are used for the fan and core airflows. The 86.4-in (2.19-m) diameter fan generates an airflow of 1,300 lb/s (590 kg/s), resulting in a bypass ratio of 5.72. The overall pressure ratio is 24.3. The engine develops a maximum static take-off thrust of 41,500 lb (185.05 kN).

The CF6-32 was to be a lower-thrust derivative of the CF6-6 for the Boeing 757. In 1981, GE stopped work on this engine so no longer competed with Pratt & Whitney and Rolls-Royce on this aircraft.

The CF6-50 series are rated between 51,000 and 54,000 lb (227.41 to 240.79 kN, or '25 tons') of thrust. It was launched in 1969 to power the long range McDonnell Douglas DC-10-30, and was derived from the earlier CF6-6.