1 Optimized A380-800 economic analyses:
Well I gave it a shot with Piano-X. Below is a reworked table.
Wing: -8.5T (-15% wing area).
Wingbox: nil (by far the most weight saving is in the wing (wing, engines, fuel, so there is not much bending relief).
Total OEW: -19.2T (I rounded it up to 20T, I reckon 800kg saving in fuel and hydraulics systems is reasonable).
Weight per passenger and luggage: 105kgOther assumptions:
engines tech level kept the same. No SFC change was used in this calculation for the initial model, so no “they gave us outdated engines” bullshit has gone into the equation.Caveats
1 I did not account for the expensive weight saving measures Airbus took to get the 800 lighter. I don’t know how much weight was saved and how much it cost, so left it as is. That means that in reality an optimized 800 would’ve realistically have been a bit heavier than the calculated values here, but also significantly cheaper. So the expensive real life weight savings are also in this model. Obviously it would’ve been slightly cheaper anyway, as it’s 20T lighter, so material cost will be lower.
2 MLW and MZFW are estimates and are important to determine a realistic payload. If these estimates are too low, then the plane needs to get heavier to carry the required payload. Expert review of the used values is very welcome, to improve the fidelity of the model. Overall I think the fuel saving could potentially reduce to a minimum of around 15% compared to the 19% calculated in the model.
Induced and parasitic drag factors used in the piano-x model are listed below the table.
The 569T MTOW variant of the original A380 is used, because that's what available in Piano-X.Original A380-800 vs. a more optimized 500T design and follow on models:2 CASM improvement sufficient to have an impact on A380 sales and the overall market?
To come back to the question asked in post#89
Could a competitive A380, with viable next generations have been built with that generation engines within a 80m box?
To answer that question two main sub questions have to be asked:
1 At what CASM does the revenue potential of such an A380 start to outweigh the yield dilution and frequency drawback vs. a smaller twin?
2 What CASM could’ve been achievable for the A380 given the 80m span limitation and that (engine) generation technology?
So to first answer the second question. Based on the Piano-X calculation the fuel saving could’ve been as much as 19% accompanied with the a CASM reduction of 10%. To then follow on with the first question, I think this CASM reduction would be significant enough to more effectively offset the yield and frequency disadvantage of the A380. Lower cost per seat, means more profit per seat and more seats profitably filled. Making more follow on sales and a broader customer base more likely.
This would most likely also have meant there would have been a business case for a NEO model. The A380 was not competitive enough compared to the 77W. Logically the A380NEO design studies Airbus did proved that an A380NEO based on an unoptimized 800 was also not going to be competitive against a 777x or A350 either. Now having optimized 800, with a 10% CASM reduction, means that the airplane to base a possible NEO on would’ve been much more competitive by itself. So the business case for a stretched NEO model would significantly improve as well. The Piano-X seems to indicate this as well with a calculated 18-21% CASM improvement over the original A380-800.
I feel in the more recent posts in this thread the difference between the market success of the real life A380-800 and the potential success of an more optimized 800, has again started to blur again. Using the lack of success of the A380 as is, as an argument to state that VLA can't be viable against the twins. The above analyses tries to bring back more nuance to that discussion. Based on the above calculation I reckon a oversee-ably sized, yet profitable niche for a well executed double decker and follow on models was there, had it been better optimized for the size on offer instead of for the rather bizarre market projections Airbus had at the time.
Any expert feedback on the numbers used in the calculation are very welcome to rerun the calculation and add credibility and usefulness to the analyses.