It is amazing how close fuel burn is for both frames. My question is in regards to the assumed 30t payload.
Where is this assumption coming from? Second, is it certain both frames have the legs to fly the mission at 30t?
And btw....thanks for the information. It is very interesting.
I fully expect the GE engine to have even lower TSFC. It has variable turbine cooling, more precise turbine clearance control, and a rediculous number of cooling looks on the engine. All of that stuff adds weight and cost to the engine, all benefits long haul fuel burn.
The competition is still too close to call. Just a data point.
Yes, we have a few data points based on models that have some error with assumptions on starting figures that have some flex based on engines that change over time whilst flying through windy conditions during different periods of the year with differing loads. That doesn’t even factor in the cost of the plane the navigation fees, the maintenance, the crew, the ground support systems and training and even then it’s for just one route and realistically QF have to make this work on a network level and even integrate with other carriers. An aircraft could easily burn more fuel to carry lower payload and be a mor expensive aircraft to buy but still be a better option to select for QF.
Still, Top trumps is fun!
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Thanks very much for doing this modelling work Fred. One of the few things that make this forum worth visiting regularly is when someone tries to rise above the rhetoric and understand what is actually going on by developing and then evolving a model. Thanks.
Understandably there is a huge focus on SYD-LHR as it is the "holy grail" of ULH flights.
My understanding is that Project Sunrise is about ULH non-stops to all sorts of destinations, not just SYD-LHR - it's actually a principle, not a sector
We seem to be missing a fundamental then in what might be the biggest single factor swaying the decision - which frame is best suited to the balance of those ULH routes, of which SYD-LHR is the longest.
Would you be able to develop your model to show what happens as the range reduces in, say 1 hour, or 500nm increments?
Or if it is simpler, by 2 x 1000nm/2hour steps
Stepping outside the model for a bit, I tend to agree with those who suggest that the Project Sunrise platform will be part of a package of orders.
In this case my opinion is that this will go to the A350XWB.
1. There is little barrier to entry inasmuch as the performance difference does not look to be great over the whole operating window - QF say that both contenders do the job.
2. QF probably hold cancellation charges from the A380's that can be carried over to the A350
3. The A350 is almost certainly way cheaper to procure - it is a) a smaller, lighter frame, and b) will roll off a production line delivering 10-12 frames per month across a whole family, not the 4-5 per month predicted for the 777X. That will bring the same economy of scale advantage to the A350 that the 787 enjoys
Both of those differentiators focus on acquisition cost, and we all know that over the whole lifecycle, that is not a great part of the total cost of ownership (TCO).
However, in my view a myopic focus on the TCO ignores the significance of captial cost as an enabler, for financing, cashflow etc. There is an "NPV" component to capital cost IMO that makes it much more significant than the raw TCO figures suggest.
Put simply, the solution needs to be affordable from the outset.
I think it will be close. And I have no issue with being shown to be wrong - those were just my thoughts.
Both contenders will be amazing aircraft.
For me the A350 will be the more amazing for its ability to cross a "vacuum" in which it is unable to perform mid-range missions, but can then demonstrably undertake missions that are much more challenging. I know of no other frame that exhibits this characteristic