Wellington Airport has signed a Memorandum of Understanding with a giant Chinese construction firm to work as a partner on the proposed extension to its runway.

Photo: WIAL

The airport stressed in a statement that this is not a final process: the matter still needs to win resource consent at the Environment Court.

There would also need to be what it calls a robust competitive tender to win the contract to do the work.

The statement does not mention two other hiccups: the need to win enough money to pay for the work and the need to win a court case brought by the Airline Pilots Association on safety grounds.

The statement adds a second Memorandum of Understanding that aims to promote Wellington as a destination for Chinese travellers.

It was applauded by Matt Clarke, Wellington Airport chief commercial officer, who called it a significant opportunity for the capital.

"We recognise the huge potential of the Chinese visitor market and have been working for several years on expanding our networks in mainland China and building relationships to promote Wellington as a destination.

"The signing of the Memorandums is a significant symbolic step."

But the airport runway extension remains a major hurdle, with or without an MOU.

A ruling from the Supreme Court on the Airline Pilots Association case is not expected until next year.

The court case rests on the provision of 90m at the end of the runway as a safety area - the legal minimum.

The majority of accidents happen on take-off and landing, and safety areas minimise the danger of missing the runway.

Wellington Airport asked the Civil Aviation Authority (CAA) if it could stick with the 90m minimum if it got permission to lengthen the runway, and won, but this was overturned later in court.

The Airline Pilots' Association argues the safety area must extend to 240m if practicable.

The cost of the extension is also a problem: $330 million.

It would also need to win resource consent and several local residents have sworn to fight against that.