Originally Posted by Stalins ugly Brother
However, taking into consideration your point in space at the time of the said failure I would be very hesitant to leave the airspace of a major port and fly eight hours because I can. I would still return or divert to the most suitable airport for the pax/crew/company/ and me. If that's eight hours so be it, but if it's two hours guess where I'm going?
Modern aircraft are a flying computer networks. The airlines engineering control on the ground can see the different systems, they can see the engine parameters. They have a good idea of what has happened as quick as the pilots do.
With the fuel load onboard they could go a long way on 3 engines. The aircraft would have been well above the maximum landing weight, so unless they were on fire, it will be some time before they could have landed. Landing or doing a missed approach on 3 engines at maximum landing weight does not have the same buffers compared to a lighter fuel load.
If they went to Singapore, they could have all the passenger handling aspects done during the 8 hour flight, and possibly an engine on its way to meet the aircraft from DXB. Good luck quickly getting hotel rooms for everyone late at night in Sydney.
Flying for 8+ hours on 3 engines in a quad would happen worldwide several times a year. You may recall a case where BA had a compressor stall leaving LAX, and went onto Manchester on 3 engines. the FAA controller filed a complaint as he saw flames coming from the aircraft, it was his opinion they should have landed.