They do pay off for large congested airports with limited landing slots (e.g. Beijing between Guangzhou, which is the only 380 I’ve flown on). But this isn’t as much of a problem as we thought it would be 20 years ago. Incidentally, this used to be why Japan flew so many 747s on domestic routes.
Right, but in order for that to work you need to be able to consistently fill the planes to capacity. That's not as easy as it sounds. There's a limited number of routes where it makes sense, so that means you don't really have an economy of scale opportunity.
Yes, for sure. It makes sense on a few routes in china ATM but as airport infrastructure and high speed rail are built out, airbus is surely in trouble (same reason japan no longer uses any 747s domestically, and Boeing has basically relegated the 747 to a freighter, albeit a very successful one).
Funny thing is that the 747 was originally designed as an airframe that could convert to a freighter. That's why the cockpit is in a bubble above the main cylinder of the fuselage--to get out of the way of the cargo.
Back then, the conventional wisdom was that eventually all passenger travel would be supersonic. Boeing put their best folks on the SST project, and the 747 was a stopgap afterthought.
Turned out that fuel efficiency was way more important than speed.
The problem is that the A380 creates so much wake turbulence that the next aircraft has to take off a bit later, negating some (but not all) of the advantage!
That depends on whether you have enough A380s out of the airport you don't need to worry about wake separation so much (I imagine, despite never being there, that Dubai is like that at certain times of day!).