Four 747-200 series aircraft were re-engined from the P&W JT9D series to the General Electric CF6-50E(2) series.
- L/N 202 (msn 20682), the first USAF's airborne command post, switched from JT9D-7A to CF6-50E engines during the E-4A/E-4B upgrade process
- L/N 204 (msn 20683), the second USAF's airborne command post, switched from JT9D-7A to CF6-50E engines during the E-4A/E-4B upgrade process
- L/N 245 (msn 20887), a 747-228F, is one of two commercial engine conversions. Atlas Air had it switched in 1999 from JT9D-7J to CF6-50E2 engines, for optimising the Atlas 747 freighter fleet on one engine type.
- L/N 253 (msn 21048), a 747-212B(SF) was the other Atlas conversion.
The certification of the re-engine Service Bulletin (SB) from the P&W JT9D-7 to the GE CF6-50E engine was (partly)paid by the USAF and Boeing (and for the first time performed at the 747-100 prototype. RA001 was only several months during 1973 powered by the GE CF6-50 engine series, after GE/747 certification was finished it was reverted back to PW power
Atlas Air used the same SB and used the CF6 pylons and derated CF6-45A2* engines from secondhand ex, ANA 747SR-81 aircraft, purchased for spare parts in 1999 (N8078H, N8078Q, and N8078M) for fleet standarization to GE CF6-50E2
* CF6-45A2 engine : Same as CF6-50E2 except for reduced ratings specified at increased flat rating ambient temperature.
See also :
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