Why 777-300ER has GE engines?But 200 and 300 have RR?
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The GE9X which will power the 777X family, will not be a a higher thrust engine than the -110/5 powering the -200LR and 300ER.
The MTOW for the 777-9X will be 344,000kg versus the 351,000kg on the -300ER
The thrust of the GE9X will be 102k versus the 115k on the -115B
The MTOW for the 777-9X will be 344,000kg versus the 351,000kg on the -300ER
The thrust of the GE9X will be 102k versus the 115k on the -115B
Last edited by B-HKD; 13th Sep 2013 at 22:22.
That's a weight saving per aircraft for RR of 2 metric tons (5.5 tons wet?); that's a lot of fuel/payload. GE must have offered the juiciest deal imaginable to sell that to Emirates; two extra tons (about 1% [2.5% wet?] of the aircraft's maximum fuel load) hauled all over the world throughout the service life of an aircraft is a large amount of cash.
Their geared fan is interesting; to my mind it would allow them to design for optimum LP and HP shaft speeds (just like RR can for their IP and HP shafts), and choose the ideal fan speed by picking a gear ratio (just like RR do with their LP shaft).
Which reminds me, weather permitting, tomorrow should see the first flight of the CSeries.
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√Interesting, but you left out an important part - what's the relative fuel burn between the two engines? Even a 1% fuel burn advantage is huge money over the life of an airplane (especially a long-haul like the A380). Unfortunately both the engine companies and the airframe manufactures consider fuel burn numbers to be proprietary, so unless you're a legitimate potential buyer they tend to be pretty tight lipped. So while I have knowledge about relative fuel burn numbers on some Boeing models, I can't repeat them - and I obviously know little about brand A fuel burn numbers.
To drag a 777-300ER from say SIN/HKG to LHR with around 50t payload the fuel burn will be around 100t so that 1% saving equates to 1200 litres just on a single flight.
But compare that to a 747-400 which needs closer to 135t (for similar loads) or even a A380 which gets towards 150t (for closer to 55t payload although the mix is more pax and less freight)