May have been a fuel/fuel reserve issue
Edit
https://www.stuff.co.nz/travel/travel-troubles/119044720/qantas-a380-makes-unscheduled-visit-to-auckland-airport-after-medical-emergency
A Qantas A380 made an unscheduled visit to New Zealand on Saturday after a passenger on board suffered a medical emergency.
A Qantas spokesperson said flight QF8 from Dallas-Fort Worth to Sydney was originally diverted to Nadi, Fiji, following a medical emergency on board.
Due to crew duty limits, after the unscheduled stop in Nadi the aircraft was not able to reach Australia so the pilots flew to Auckland International Airport where Qantas had more options to accommodate customers on another flight, the spokesperson said.
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