CF6-50 gas turbine engines at a maintenance facilty during overhaul.

- Image ID: B88ER1
CF6-50 gas turbine engines at a maintenance facilty during overhaul.
TONY LOCKHART / Alamy Stock Photo
Image ID: B88ER1
The General Electric CF6 is a family of high-bypass turbofan engines. A development of the first high-power high-bypass jet engine available, the TF39, the CF6 powers a wide variety of civilian airliners. The basic engine core formed the basis for the General Electric LM6000 marine and power generation turboshaft. GE Aviation intends to replace the CF6 family with the GEnx, which is expected to enter service in 2008. The CF6-50 series are high-bypass turbofan engines rated between 46,000 and 54,000 lbf (205 to 240 kN) of thrust. The CF6-50 was developed into the LM5000 industrial turboshaft engines. It was launched in 1969 to power the long range McDonnell Douglas DC-10-30, and was derived from the earlier CF6-6. 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 lbf (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. Air France became the launch customer for the A300 by ordering six aircraft in 1971. In 1975, KLM was the first airline to order the Boeing 747 powered by the CF6-50. This led further developments to the CF6 family such as the CF6-80.