The problem is not really how big the aircraft can be but more a case of how will the airport infrastructure cope? And then you have the human aspect. The weakest, most frail and unreliable things on an aircraft are passengers. Keep piling them on and after a while your HyperJumbo will be diverting all over the place because the buggers in the back keep popping their clogs. And then you have the marketing problem. Just how many people want to go from A to B? I am convinced that we are approaching saturation on some routes yet capacity keeps increasing. How long before the bloodbath? Do we need yet more capacity?
PM