The 787-9 seats more than the a330
I was looking at 2 real world airlines using the same seats, this is what I could find. Do you have examples that contradicts this?
Don't get your point, look again. You seem to validate my assumptions and calculations.
I used seats across, cabin lenght and same galley, lavatory rates for all aircraft. Often 787-9 are used for longer flights, on average increasing the number of premium seats, classes, reducing seatcounts.
As mentioned in my post I compared 2 airlines that seem to use the same layout and seats. This is EY and VS and when comparing their A333 and 789. It seems to me VS uses the same seats in J and while the layout is different in that some seats are forward facing and others face backward for EY, it is the same 1-2-1 layout in J as in the A330. If anything you would think the seats in the 789 saves space as it was introduced later and I don't know of many airlines that would willingly reduce seats in their aircraft by giving passengers more space. It is all about fitting in more seats in the space they have and making it seem like they are not taking away from passengers.
In fact the VS layout has more W seats and less Y seats and still the A330 has more seats in total. For Etihad, while they do not have the A330 in their fleet their layout as per seatguru confirms that the A330 seemingly in a similar layout with similar seats do not have a 20 seat disadvantage as you seem to have. In fact the seatguru layout seems to have more seats than the EY website for the 789 in Y, just a handful mind you. The A330 is not listed on the EY website any longer but I have found a A333 layout they had as per their website.
I know seatguru is not 100% accurate, that is why I linked to the airlines websites to confirm if they are accurate. As mentioned the Etihad layout has less seats for the 789 than seatguru but not that much. The EY 78X on seatguru is not accurate at all, with almost 30 seats difference in Y. But for reference as per seatguru has the following capacities for these aircraft as they seem to be accurate, even with a slight difference between the EY layout for the 789 (3 or 4 seat less).
EY A333 - 231 seats in 3 classes including F (8F and 32 J)
EY 789 - 231 seats in 3 classes including F (8F and 28J)
VS A333 - 264 seats in 3 classes but no F (31J and 48W)
VS 789 - 258 seats in 3 classes but no F (31J and 35W)
As per numbers above the premium heavy 789 is not reflected either, as the A333 has more premium seats than the 789 but doesn't seat less. But again this is not a criticism of your sheet or numbers, just an observation of real world layouts.Etihad A330-300 3 ClassEtihad 787-9 3 ClassVirgin Atlantic A330Virgin Atlantic 787
Becareful when comparing the A333 and B789 seat counts at a lot of these airlines. In a lot of cases the 2 aircraft aren't using the same type of seats and a bigger impact is that you will typically see the 789 in a 4 abreast configuration in J while the A333 is in a 6 abreast configuration.
I have been careful to avoid making comparisons that uses different layout or seats. Both EY and VS seems to use the same seats in F, J, W and Y so it seems a fair comparison. It is only 2 airlines though, but still food for thought I would think. I think it does go against what we automatically assume, that the 789 is bigger than the A339 because it can seat one extra per row in Y when using similar layouts.
All my observations are just that, observations. I am more than happy to be corrected if this is not the case.