What is the technical, mechanical and economic feasibility of using the Airbus A380 for short haul flights of under 4 hours in its 800 plus seat configuration? I'm talking about cost and economies of scale, frequency of repairs and service etc.
I can't say if anyone has looked at a short-haul version of the A380, but we can look to the Boeing 747-400D for comparison.
In addition to removing the wingtip extensions and winglets as described in the Wikipedia article, a friend at Boeing described to me other changes needed. Boeing beefed up the wing box due to the increased landing cycles. There were also some changes to the brakes to improve cooling as the short flights didn't provide adequate time to cool the brakes passively.
It should be noted that ANA was the only customer with 19 aircraft built. They retired the last of them 3 years ago. So it would appear that there isn't much of a market for a short haul jumbo.
Compared to several other airliners (Boeing 787), A380 is less fuel efficient. The fuel efficiency of B787 is 102 mpg per seat, compared to A380 is 74 mpg per seat. The maximum seats Emirates offer on A380 is 615. At present, Emirates does not have a B787, but B787's seating capacity is around 300, when classes are implemented.
Taking the example of people traveling between UAE (Abu Dhabi and Dubai) and Doha, there is a very high demand. A single flight of A380 is more fuel efficient than two flights of B787, when a single A380 is carrying almost twice as many passengers as B787. If there is a demand, economy is better.
When a single aircraft flies instead of two, it will also decrease congestion, at the airports, and in the airspace.
However, when A380 is used on smaller routes as opposed to longer ones, it will increase its cycles faster.
Simply comparing fuel efficiency can be flawed (noted in this answer) as different phases of a flight cost different.
Emirates also operates other smaller routes besides Doha.
Sure can. There are number of airlines on the Pacific rim areas which use 747s as puddle jumpers, making multiple short hop flights and the jet, simply because there is so much passenger travel between destinations there that an airplane like a 747 all of a sudden becomes useful for that purpose. It’s not unreasonable to think that in the near future past your demands in that region could potential he make an A380 configured for 700-800 seat cabin arrangements a feasible option here. I don’t know if structural reinforcement here would be needed as the above poster stated, primarily because the aircraft would take off with only a fraction of the fuel on board that without an intercontinental flight. 30,000 to 40,000 pounds of fuel would be useful on such routes, not the 380,000 to 400,000 pounds of fuel typically carried on a long transcontinental route.