General Electric · Case study
General Electric CF6
The engine that took GE from the military into the heart of the widebody market. Derived from the TF39 that powered the C-5 Galaxy, the CF6 spent five decades under the wings of nearly every long-haul twin and tri-jet.
Architecture
The CF6 is a two-spool high-bypass turbofan whose lineage runs back to the TF39, the first large high-bypass engine, built for the C-5 military transport. A single large fan on the low-pressure spool feeds the bypass duct; a high-pressure compressor, annular combustor and air-cooled high-pressure turbine make up the core.
Across the -6, -50, -80A, -80C2 and -80E1 variants the family grew its fan, raised its pressure ratio and climbed in thrust, but the basic two-spool widebody layout stayed constant — a textbook example of stretching one sound architecture across a generation of aircraft.
The cycle
By widebody standards the CF6 ran a moderate, robust cycle: a bypass ratio in the four-to-five range and an overall pressure ratio near thirty. That balance favoured durability and predictable maintenance over chasing the last percentage point of fuel burn, which suited the long-haul operators that flew it hardest.
Successive variants lifted the core pressure ratio and turbine temperature as materials improved, keeping the engine competitive long after its 1971 debut.
Engineering significance
The CF6 established General Electric as a first-rank supplier of large commercial engines and seeded the core technology GE would carry into the CFM56 and, later, the GE90. Its long production run and broad airframe coverage made it one of the most widely flown widebody engines ever built.
Applications
Boeing 747 · 767 · Airbus A300 / A310 / A330 · McDonnell Douglas DC-10 / MD-11
Explore a representative turbofan cycle for this engine class in the interactive console.
Open the simulator →All figures are public-estimated and approximate, given for a representative variant; exact values vary by sub-model and rating. PropulsionLab is an educational project and is not affiliated with any engine manufacturer. Engine names are the trademarks of their respective owners.