Update: Thursday 24 February
New Zealand Air Traffic Control organisation Airways NZ has contacted Australian Business Traveller with information regarding New Zealand's air traffic control centre at Christchurch on 22 February.
A spokeswoman confirmed that "Christchurch Tower remained operational throughout", correcting information that had come direct from Christchurch Airport representatives after Tuesday's earthquake.
The airport was not authorised by Airways NZ to speak for the structure of the tower, the spokeswoman said.
Airways NZ confirmed that the Christchurch radar centre (which controls most NZ air traffic) was out of operation for approximately 90 minutes.
Operations were transferred to Auckland and pilots took the standard step "to take control of their own situation and speak/communicate directly with each other to maintain safe separation", according to the spokeswoman.
Christchurch Airport says its air traffic control tower swayed vigorously in this morning's earthquake, but did not sustain damage.
"Our air traffic control tower is unbelievable - it's designed to withstand category eight or nine earthquakes," said Monique Oomen, Christchurch Airport spokesperson.
"Its foundations go down one and a half stories into the ground. It will sway in an earthquake but not fall over," she said.
"In fact, the air traffic controllers are still up there -- they've chosen not to leave."
"We've just cleared the runways for medical flights and medical evacuations -- Christchurch Hospital has been evacuated so there are a lot of emergency flights that need to go out."
"At this stage the airport is closed for all commercial flights until further notice. There is minor damage to the terminal, but the airport is very likely to reopen tomorrow. We had a category seven earthquake recently and we were open again nine hours later."
Airways NZ (New Zealand's air traffic control organisation) could not be reached for comment, with its phone lines playing a recorded messages saying their offices were unattended.
Read more comprehensive coverage of the aftermath of the Christchurch earthquake, plus authoritative advice for travellers in the area and overseas.
- Christchurch airport is open for some international flights, plus arrangements are in place for Australians who have lost passports.
- Many extra flights and special fares have been arranged by Air New Zealand.
- We spoke to the Australian High Commission and DFAT to get advice for Australians in Christchurch who need consular assistance.
- Airlines have waived change fees for many tickets to and from Christchurch: full details and how to get the fees waived.