Given the 35 ton OEW difference shown on that Airbus marketing slide, It is hard to believe that QF would seriously consider the 777-9. Why would anyone operate the 777-9 over the A350-1000? The 777-9 order backlog being bigger than the A350-1000 backlog must be an illusion.
The order backlog is the only objective way to measure the progress of a development of an aircraft like the A350-1000.
This is what Airbus set out to do when it launched the A350-1000
This is what they have come up with
That photo was of the A350-1000 during its early long flight as part of the flight test program this week. The aircraft departed at 94.7% MTOW. The photo shows fuel used at that point was 33.25t 4 hours into the flight, if you take 500 kg for taxi, the flight fuel would be 32.75t. Current mass 258.9 t, so TOW=GW+FU = 291.65t. 291.65/308=94.7%.
The TAS is 497 kts at FL350, a 77W taking off at the same percentage of MTOW would be at FL330 with a TAS of 488 kt. The current fuel flow is 6800 kg/hr, a 77W after 4 hrs taking off at the same percentage of MTOW would be burning 8644 kg/hr, that represents 21.3% less fuel flow. In terms of specific range, 77W 8644/488 = 17.7 kg/nm, A350-1000 6800/497= 13.7 kg/nm, that represents a 22.8% reduction.
After 4 hours of flight time a 77W taking off at the same percentage of MTOW would have burnt 41.9 t of fuel, the A350-1000 32.75 t, that also is a 21.8% reduction. However in that time the A350 would have flown about 2% further in distance. The A350-1000 at that point had 7:22 of flight time left and estimated to burn 45.7 t (65.5-19.8), average burn for the 7:22, 45.7/7:22=6.2 t/hr for the remainder of the flight. Overall total trip fuel would have been 78.45t (45.7+32.75) for 11:22 (7:22+4:00) flight time. A 77W would burn 105.9 t over that flight time. That represents 27.5 t less fuel for the sector in percentage terms a 25.9% reduction.
Q Why would anyone operate the 777-9 over the A350-1000?
A The demand over the city pairs requires and supports the larger airframe.