The Government-chartered flight bringing stranded Kiwis home from Wuhan has just lifted off from China according to flight radar.
Air New Zealand flight 1942 departed the city at the centre of the deadly coronavirus outbreak at 1.46am (6.46am New Zealand time) - 2 hours and 46 minutes late.
The Boeing 777-200 flight has 312 seats but there are just 198 passengers on board, excluding crew, according to Air New Zealand.
At a press conference on Tuesday authorities said there were 263 people registered for the flight - it's not clear why the other registered people did not board.
The passengers were to be assessed by a St John doctor and two paramedics to decide whether they were fit enough to travel out of Wuhan.
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Authorities have said anyone suspected of having the virus will not be allowed on the flight.
The death toll from the virus stands at 427, with more than 20,000 people confirmed to have contracted the virus globally.
The majority of Air New Zealand's passengers were expected to be New Zealand citizens or permanent residents, but 50 Australians were also expected to join the flight, with the remainder from the Pacific Islands.
That includes 19 students from Papua New Guinea, who will be quarantined in New Zealand.
Precise numbers would not be known until the flight boarded in Wuhan, authorities said yesterday.
Air New Zealand's chief operational integrity and standards officer Captain David Morgan said the delay to today's flight was to be expected, given that the airline was not familiar with Wuhan Tianhe International Airport.
Turnaround took 4 hours and 20 minutes but they had contingency plans for five hours due to the complexity of working out of an unfamiliar airport as well as complex screening processes due to the special nature of the flight.
NZ1942 was part of a cluster of flights from other countries evacuating their passengers, Morgan said.
With a flight time of just over 11 hours, NZ1942 is expected to arrive at Auckland International Airport at 6.15pm, after which New Zealanders would be taken to a quarantine centre in Whangaparaoa, north of Auckland.
Australian Minister of Health Greg Hunt said it was likely the Australians would be greeted by officers from that country's Border Force and the Department of Foreign Affairs and Trade and would be taken to Christmas Island.
"The advice I have is that if they are to come to Australia, if they're not housed in New Zealand, then ... we'll be supporting them on Christmas Island," he said.
The first group of Australians evacuated from Wuhan arrived on Christmas Island overnight on Monday.
The flight to Auckland was being operated by 20 Air New Zealand employees, all of them volunteers. They include five pilots, 11 cabin crew and medical and engineering staff.
Morgan said infection control measures were in place on the flight.
These included minimal interaction between passengers and crew, who would be wearing personal protection gear. Pilots would not come into contact with passengers.