General Electric CF6 on the Boeing 747
The General Electric CF6 spanned the 747 from 1975 to the -400ER, rolling out on KLM’s 747-200M in 1975. Versions include the CF6-50, the 10-percent-derated CF6-45 for ANA 747SRs, and the CF6-80C2 on -300s and most -400s.
General Electric’s high-bypass CF6 gave airlines their first alternative to the JT9D and stayed on the 747 for four decades, from the -200 to the -400ER.
| Key facts | |
|---|---|
| Applications | 747-200, -200B, -200M, -200F, 747SR, -300, -400, -400ER; also E-4A and VC-25A |
| Key versions | CF6-50 (51,000–54,000 lbf); CF6-45A2 46,500 lbf (747SR); CF6-80C2B1 56,700 lbf (-300); B1F 57,900 lbf (-400); B5F 62,100 lbf (-400ER) |
| Bypass / fan | CF6-50 4.26:1, 86.4 in fan; CF6-80C2 5.15–5.31:1, 93.0 in fan |
| First customer | KLM — first CF6-powered 747 (747-200M), ordered October 1975 |
The first GE-powered 747 was a 747-200, not a 747-100 — the -100 was JT9D-exclusive. The USAF’s selection of the CF6-50 for the E-4A 747 in 1972 helped clear the way, and KLM’s October 1975 order for a CF6-powered 747-200M Combi brought the engine to the commercial fleet. JAL and Korean Air followed.
GE tailored engines for specific 747 customers: the CF6-45A2, a 10-percent-derated CF6-50 built only for ANA’s high-cycle 747SR domestic operations, and the heavier CF6-50E for the 747-200 and 747-200F.
The CF6-80C2 was the decisive version, powering the 747-300 and then most 747-400s (the B1F at 57,900 lbf) plus the 747-400ER (B5F at 62,100 lbf). It became the most-flown widebody engine in history, with more than 300 million hours, and remains the benchmark the 747-8’s GEnx was measured against.
Sources
- General Electric CF6 article — Wikipedia
- Boeing 747 operational history — Wikipedia
- CF6-80C2 data sheet — GE Aerospace
- 747-400 Airplane Characteristics for Airport Planning — Boeing
Sources
Facts on this page are checked against the primary and institutional references below.
- General Electric CF6 article — Wikipedia
- Boeing 747 operational history — Wikipedia
- CF6-80C2 data sheet — GE Aerospace
- 747-400 Airplane Characteristics for Airport Planning — Boeing
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