An Air New Zealand flight from Auckland to Buenos Aires has spent less than two hours in the air before returning to Auckland International Airport.
The Boeing 787-9 Dreamliner left the airport at 8.33pm and was due to arrive in Argentina at about 7am Thursday, NZ time.
But flight trackers show it did a U-turn shortly after takeoff, before spending some time over the Pacific Ocean and then returning to touch down at the airport around 10pm.
An Air New Zealand spokeswoman said the flight had returned as a precaution due to "a possible engineering issue".
"The aircraft, which was less than an hour into its journey, circled for a short time to reduce fuel weight before landing without incident at around 9.50pm."
Passengers have been booked to travel on an alternative service tomorrow, she said.