Pilot survives chopper plunge

An Arrowtown pilot had to swim for safety when his helicopter plunged into the sea near the mouth of Milford Sound this week.

Mark Cotton said his training kicked in and he had managed to slow the $750,000 Hughes 500 helicopter's descent by auto-rotation, an emergency manoeuvre which keeps the blade spinning despite loss of engine power.

After extracting himself unhurt from the helicopter, which subsequently sank, about 4.45pm on Wednesday, he then swam about 20m to safety at the edge of the coast.

The Otago Daily Times reported the emergency happened when Mr Cotton was returning to his Haast base after a 90-minute, relatively low-altitude survey of wild deer, carried out on behalf of his company, Snowline Safaris.

His machine's emergency radio beacon did not activate on impact and he spent about two and a-half hours sitting on a rock before he attracted the attention of the crew of a Milford Sound-based crayfish boat heading back into the sound.

He said he had advised the Civil Aviation Authority about the accident and had already had discussions with CAA staff.

Mr Cotton said he would go back to the site to see if his helicopter was retrievable, but he had no idea how deep the water was.

- NZPA