Air New Zealand has thanked transtasman travellers for their patience after the mixed response to charter planes filling in for Dreamliners that need engine maintenance and repairs.

Chief executive Christopher Luxon also defended the airline's handling of the Rolls-Royce engine problems which led to one being shut down after suffering damage from turbine blades soon after take-off to Japan late last year.

Luxon said the aircraft also suffered ''superficial, not structural'' damage but at no time was passenger safety compromised.

''At no point were any of our passengers at risk - there is a system that has multiple layers,'' he told the Business Herald after releasing the airline's six-month result.


''We're taking very aggressive, very assertive action to make sure we get those engines sorted.''

There was an accelerated maintenance programme underway, with engines being flown to Singapore for checks and, where necessary, turbine blades replaced.

The issue has hit the worldwide Dreamliner fleet powered by Rolls-Royce engines — about 300 planes — and Luxon said his airline's maintenance and engineering expertise had helped it work through it better than others.

Because of disruption among its 11-strong Boeing 787-9 Dreamliner fleet, Air New Zealand contracted Portuguese charter operator Hi Fly to operate two aircraft - one between Auckland and Perth and the other between Auckland and Sydney.

While flights had to be cancelled and there were delays in the days after two Dreamliner engine incidents on successive days in early December, the schedule had recovered.

''We managed to keep our network working - we appreciate the Hi Fly product may not be the same as Air New Zealand, but having said that our customers have been extremely grateful that they've been able to get from A to B over the Christmas period.''

An Air New Zealand Boeing 787 Dreamliner at Auckland Airport. Photo / Grant Bradley
An Air New Zealand Boeing 787 Dreamliner at Auckland Airport. Photo / Grant Bradley

When the Hi Fly planes were first brought in it was thought they would be here just for the holiday period, but they could be here until mid-April.

''I'm pleased and thankful to the public because our choice, like any airline around the world, would be to cancel lots of flights - we didn't want to do that,'' Luxon said.


Read more Inside Air NZ's Portuguese charter planes

The airline had been hit with a high number of events beyond its control in the six-month period to December 31 and since.

This included the Refining NZ pipeline crisis, the Dreamliner engine issues and, since the start of this year, extreme weather.

The airline had studied weather records for the past 20 years which showed one or two big weather events capable of throwing the network into chaos.

''What we've had in the last 45 days is four big weather events that make flying in this country incredibly difficult to do. It's building a culture and resilience within it so our people are thinking about those events and make that the new normal.''

The airline made an early call to curtail operations from some airports as weather from ex-cyclone Gita hit on Tuesday, giving customers certainty, said Luxon.

In the six-month period the airline posted a 7.4 per cent fall in first-half pre-tax profit as rising fuel prices offset record-high passenger revenue.

Luxon said the fuel price was $73 million higher than in the corresponding period a year ago.

Disruption following the pipeline outage had cost the airline about $5m and while not ''super material'' it was looking ways to recoup that.

Pre-tax earnings fell to $323 million to December 31 from $349m in the same period a year earlier. The prior period also included a $22m gain related to the divestment of Virgin Australia, it said.

Net profit in the first half fell 9.4 per cent to $232m or from $256m in the prior period. Operating revenue was $2.7 billion, up 5.6 per cent. The result was driven by operating revenue growth of 5.6 per cent, with robust demand across all markets and particularly strong growth in the short-haul network. Passenger revenue reached an all-time record for an interim result, at $2.3b.

The airline declared a fully imputed interim dividend of 11 cents per share which will be paid on March 16 to investors on record as of the close of business on March 9.

Its shares were trading up 13 per cent at $3.10 in late morning trading.