Air New Zealand flight 101 sent out an emergency call mid-air when it was 45 minutes out from its destination on Wednesday.
The flight from Auckland bound for Sydney International Airport sent out the emergency alert at 10:08am (NZ time).
According to an Air New Zealand spokesperson, a passenger experienced a medical emergency, triggering the alert.
For privacy reasons, details of the medical emergency could not be shared, the spokesperson said.
The flight was predicted to land half an hour later than originally scheduled due to the alert but ended up landing 11 minutes earlier than anticipated.