The vexed subject of air traffic over wilderness areas is high on the agenda at next week's meeting of the West Coast Tai Poutini Conservation Board.
The board has posed a number of questions to DOC, asking it to clarify its policies and management of tourism flights.
It was hoping for some answers at next week's meeting.
However, chairman Dr Keith Morfett said answers would not be forthcoming this time around.
"Naturally we're disappointed but it is a complex issue and DOC is still working on its response."
DOC had always taken a permissive stance to aircraft flying in and around the glaciers because of the importance of the industry to tourism.
The board was comfortable with that, Dr Morfett said.
"But there've been a lot of complaints from trampers and climbers about helicopters and planes flying over so-called quiet areas, like the Adams Wilderness Area, and the country back of Hokitika."
Air traffic had also increased over the Paparoa National Park which was established as a quiet park, but had become a lot noisier since its management plan was reviewed by DOC in 2016, Dr Morfett said.
"There's a widespread perception among recreational user groups in our parks and wilderness areas that tourism air traffic is out of control, and we are hoping for some clarity from DOC on what is and isn't being permitted."
DOC now expected to have its responses to the board's concerns ready for its February meeting, Dr Morfett said.
The board meets at 9am on Wednesday 27 November at St John in Greymouth, with a public forum scheduled for 1pm.