Wellington Airport is going to the Supreme Court over its plan to extend the runway.
The airport is asking the Supreme Court to clarify the regulatory requirements around the length of safety areas, which must be between 90 and 240 metres.
The airport wants to add 355m to the south end of the runway, including a safety area of 90m at the end.
The Court of Appeal recently overturned a Civil Aviation Authority decision to approve the 90m runway safety area, saying it could instead take up more of the planned extension or contain an arresting system.
Wellington Airport chief executive Steve Sanderson said it was "vital Wellington Airport has certainty and clarity over how the regulatory requirements relating to aviation safety are applied".
At the same time, the airport would ask the Environment Court to adjourn its resource consent hearings for the extension until the Supreme Court had heard, and ruled on, the appeal.
Pilots' association unhappy with further legal action
The New Zealand Airline Pilots' Association (NZALPA), which sought the judicial review, said it was disappointed more ratepayer money would be used to fight the ruling.
"NZALPA's pilots and air traffic controllers are very disappointed that [Wellington International Airport] is now intending to spend even more on what is effectively a Wellington ratepayer-funded fight against a decision directing a safety review," said its president, Tim Robinson.
"This could instead be spent on an appropriate safety mechanism that our members, the travelling public and the wider reputation of Wellington as a safe tourism destination would benefit from.
"Seeking leave to table an appeal in the Supreme Court serves no one's interests except to demonstrate a 'win at all costs' mentality," Mr Robinson said.
"Our board will now consider our legal options keeping in mind that we are a union and do not have the resources, including those owned by the capital's ratepayers, of an international airport at our disposal."
In its request to the Environment Court, the airport's lawyers said the airport was still committed to the runway extension.
The lawyers, Francis Cooke QC and Amanda Dewar, said there were "a number of possible outcomes from the appeal proceedings".
They said that could mean changing the resource consent application for an even longer runway extension, devoting more of the extension to the safety area or abandoning it altogether.
A pre-hearing conference is being held at the Environment Court on Thursday to discuss the airport's request.
Civil Aviation Authority spokesperson Mike Richards said it would be monitoring the proceedings closely, and had no further comment while the legal process was under way.