The flight returned to Auckland about 9.30am this morning, Hundman said.
Shortly after 11.30am this morning, Hundman was sent a text from Air NZ saying: "As you were advised onboard, the aircraft operating your flight did not have regulatory approval to land in China and was required to return to Auckland."
An Air NZ spokeswoman told the Herald: "NZ289 Auckland to Shanghai returned to Auckland around four and a half to five hours into its journey after it was discovered a technicality meant the particular aircraft operating this service did not have Chinese regulatory authority to land in China.
"Customers will be accommodated for the day at hotels or at the airport's Strata Lounge before they depart for Shanghai on a special service at 11pm this evening.
"We know customers will be deeply disappointed and frustrated by this situation and we are very sorry for the disruption to their travel plans."
Hundman said he was "stunned if Air NZ had allowed a plane full of passengers to take off without being quite sure they would be able to land it in Shanghai".
The Air NZ spokeswoman says, "It is normal process to get a flight plan cleared by local authorities prior to departure and this was done on this occasion and was approved by Chinese Authorities. Unfortunately, it was discovered during the flight that this particular aircraft did not, in fact, have the necessary permit to land."
Meagre compensation
Reparations offered so far had been meagre, Hundman said.
"We were given hotel vouchers for the Crowne Plaza, $30 of meal vouchers for use at the airport, and taxi vouchers."
There had been no compensation offered for time lost or hassle, he said.
Hundman was allowed out of the airport to rest at the Plaza because he had a visa. Those who did not had to camp out at the Strata Lounge - the so-called "second class" option.
He said passengers were woken up by the pilot with the turnaround announcement four or five hours into the flight. He was one of a handful travelling business class, so could only gauge the reaction of a handful of passengers around him, but says all were shocked.
Hundman tweeted as the flight returned to Auckland:
The incident comes just days after an Auckland-Queenstown flight was forced to turn around, and claims passengers were "losing their minds" amid poor communication and a five-hour delay.
More details of that flight emerged today.