It's not. Running costs of a large airplane (which you need for SF-Singapore) are very expensive, especially if you're gonna run them semi-empty. Then come all the taxes and airport fees you have to pay to the airports and countries. Fly crews, repair crews, repair warehouse with some high failure components etc.
They're going to Shanghai, not Singapore. Big difference in distance. And 50 seats requires a much smaller jet than 300, see business jets.
Maintenance and spares are easily outsourced to an airline. Passenger airlines do this regularly for smaller destinations. All of the major airlines even outsource their heavy maintenance to some degree.
United Technical Operations is the maintenance, repair and overhaul division of United Airlines. We bring over 85 years of MRO experience, employee talent and operational integrity to our customers.
www.unitedtechops.com
A big thing now is manufacturer support contracts ("power by the hour") where parts and major maintenance are their problem.
Taxes may be lower because of the inherent difference in taxation. Ticketed flights are taxed as a percent of airfare, non-ticket flights pay a tax on fuel.
The class of airplane needed along with operational and "parked" costs might surprise you.
Long-haul planes have much lower utilization than short haul since you can't push in extra flights, when their flights are 13 hours long, and you want the times aligned to minimize jet lag.
DaimlerChrysler ran a daily all-business A319 between Detroit and Stuttgart, back when the company existed.
Would require a BBJ in at least a 773. Or an ACJ in at least a 333. Far too much capacity.
No, narrowbodies are perfectly fine. SFO-PVG is 5300 NM, A319CJ does 6,000 NM, albeit with lower payloads. A319neo and A321XLR is now an option.
Another option is to simply make a tech stop, see BA1.
