Three helicopters with monsoon buckets are fighting a blaze in Cardrona in Otago.
Fire and Emergency says the fire is burning near the access road to the snow farm.
The choppers were called in when firefighting crews from Wanaka and Luggate found the terrain too difficult to get to the flames.
Around 150 hectares of vegetation has been destroyed and Fire and Emergency expects it will take another hour to bring the final five hectares under control.