The Boeing ACAPS data and tables appear to match quite closely as to what QF achieve on the LHR-PER route as well as posts showing actual data from other airlines. The typical amount of fuel on board on landing for a 787 variant appears to be ~5t so there is no reason to assume that there would be anything special done for the sunrise routes and therefore no additional assumptions or reductions justified in the calculating of the capability.
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I will allow others to pass their own judgement on weather there is technical merit to your posts.
The payload range validated the "rough calibration" of the model. Entering into the details at this stage is useless.
The chart given by Boeing below indicates that the 777-9 can carry 426 passengers at 225 lb per passengers over 7,285 nm.Obviously the picture given by Boeing includes all the required stuff to fly with those passengers
Below is payload chart with the point stated in the above. The estimated OEW, that is only the result
of calibration relative to the information is stated in the payload range diagram. Obviously this payload range diagram is using the typical well known reserve fuel policy that is way too conservative for this kind of distances.
The estimated OEW (which is merely a result of matching 426 pax over 7,285 nm) happens to be around 407,300 lbs. It is the OEW (including catering waste water precharge, crew, unuseable fuel, documentation etc.) to carry 426 passengers.
The red point represents the number given by Boeing's picture, again I insist that the estimated OEW includes everything that is required to carry those passengers over 7,285 nm. And the estimated OEW is a result of the estimation,
not a "bottom up" calculation. I also insist that the numbers given by Boeing certainly uses the usual industry standard contingency fuel with 5% of trip fuel and an alternate distance of 200 nm.
A more realistic fuel reserve of 7.4 tonnes or 16,353 lb
, as indicated by the calculator picture below, allows to carry more than 200 passengers over 9,600 nm.
That's so simple to understand. You do not need more to evaluate its capability at this stage.
As for the 15% efficiency improvement, it is based on the fact GE initially announced that GE9X would be 12% better than GE90-115B from SFC perspective.
Later on they reduced the ambition to only 10% SFC improvement relative to the GE90-115B. From the wing geometry of the 777-9 we can deduce easily that the aspect ratio has increased by a significant amount. The estimated L/D (or aerodynamic finesse or Lift over Drag) improvement would be around 6 to 7%. However a credit for only 5% was used. So, using Breguet Leduc formula one can deduce the SAR (Specific Air Range) Improvement to be about 15%.
So yes, the 777-9 can carry more than 200 passengers over 9,600 nm equivalent still air distance.
The most agressive assumptions could give around 260 passengers over 9,600 nm
, but it would include some weight optimization.
So you didn't notice the fuel reserve in the example was as little as 16,353 lb or only 7.4 tonnes
All the above being said, there is absolutely no doubt Qantas will order some A330neo or A350 at one point as a kind of compensation for the cancellation of 8 A380. It would be consistent with the recent Emirates' A350 orders.