Air New Zealand is cancelling some long-haul flights over the coming weeks and delaying others after two incidents involving engines on its Dreamliners.
A flight to Japan returned to Auckland shortly after takeoff on Tuesday after the pilot shut down one of the plane's engines as a precaution.
There was also an issue on a flight to Buenos Aires on Wednesday and that also turned back.
Air NZ says engine maker Rolls-Royce has advised that some of the Trent 1000 engines in the airline's Boeing 787-9 fleet require maintenance sooner than previously indicated.
"Rolls-Royce does not have any replacement engines available while this maintenance work is undertaken which means some schedule changes are unavoidable," it said.
"In addition to these changes, Air New Zealand is focused on securing replacement aircraft capacity."
Passengers affected would be contacted with new travel information, while Air NZ would update any schedule changes on its website.
Planned schedule changes until Sunday:
NZ175 - Auckland-Perth, cancelled
NZ178 - Perth-Auckland, cancelled
NZ31 - Buenos Aires-Auckland, delayed 8 hours 55 minutes
NZ282 - Auckland-Singapore, delayed 35 minutes
NZ289 - Auckland-Shanghai, delayed 5 hours 40 minutes
NZ97 - Auckland-Osaka, cancelled
NZ98 - Osaka-Auckland, cancelled
NZ175 - Auckland-Perth, delayed 3 hours 30 minutes
NZ162 - Perth-Christchurch, delayed 7 hours 35 minutes
NZ161- Christchurch-Perth, delayed 4 hours 50 minutes
NZ289 - Auckland-Shanghai, delayed 7 hours, 30 minutes
NZ288 - Shanghai-Auckland, delayed 1 hour 45 minutes
NZ61 - Auckland-Rarotonga-Sydney, delayed 1 hour 30 minutes
NZ30 - Auckland-Buenos Aires, delayed 5 hours 35 minutes
NZ289 - Auckland-Shanghai, delayed 7 hours 30 minutes
NZ288 - Shanghai-Auckland, delayed 3 hours
NZ28 - Auckland-Houston, cancelled
NZ29 - Houston-Auckland, cancelled
NZ289 - Auckland-Shanghai, delayed 1 hour 16 minutes