The Wanaka Stakeholders Group, representing about 3,000 people, says it will file judicial review proceedings in the coming days.
The group sent letters this morning to Queenstown-Lakes district Mayor Jim Boult, local councillors and the directors of Queenstown Airport Corporation Ltd (QAC).
Wanaka Stakeholders Group chair, Michael Ross, said that the group was "disappointed to be forced into the position to take this step".
Mr Ross said that the group had been asking both the council and QAC for details relating to Wanaka Airport for "many months", and that it had been stonewalled.
"Nobody wants to take legal action like this," said Mr Ross, "but we now have no choice".
"The Upper Clutha community is deeply frustrated with the lack of transparency, absence of proper community consultation and wafer thin information provided by our local council and the QAC. We are deeply concerned at what they appear to be planning, and they are just not listening to what the community is saying."
Mr Ross also pointed out that judicial review is a costly exercise for everyone.
"We are now having to raise funds from the community to take legal action against the council - the very organisation which is meant to be working for us, not against us. The irony of this should not be lost on they mayor or his team."
Mr Ross declined to discuss the details of the group's legal case, which will be filed within "the next few days".
The letter said the review request would contend that in "effectively handing over ownership and/or control of existing Wanaka airport to QAC by a 100 year "lease" . . . . following the so-called "consultation"," the council acted in breach of the Local Government Act, meaning any contracts entered into were unlawful, making any related decisions around such agreements judicially reviewable.
