'Intense investigation': Air traffic control outage to be scrutinised

An air traffic control IT systems outage to the oceanic area affected flights in New Zealand and Australia yesterday, including this Brisbane-bound flight from Wellington, on which passengers were told the Oceania airspace was closed. Photo: Flight Radar

An air traffic control systems disruption which affected trans-Tasman flights was highly unusual and will be the subject of a full review, an independent aviation commentator says.

The IT systems outage on Saturday night forced some flights into a holding pattern, while others had to divert or were held on the ground.

Airways New Zealand said the outage affected its main oceanic area's air traffic control system from 4.30pm Saturday, impacting flights in New Zealand and Australia. Air traffic control operations were switched to a back-up system during the outage, before the main system was restored and normal operations were back up by 5.30pm Saturday.

Five flights were held in the air for about 40 minutes during the outage. Three of those were then diverted back to New Zealand and two were able to carry on to their destination.

Airways has yet to provide any details about the cause.

Aviation commentator Irene King, a former Aviation NZ chief executive, said Airways' management of the Oceanic air traffic control system was typically very robust and the glitch was highly unusual.

"They'll be doing a pretty intense investigation as to what went wrong and why. This team are extraordinarily practised, and that's part of the assurance that they provide to the airlines and to the travelling public."

King said she was not aware of any cases like this happening before in the airspace managed by airways.