'I thought I was going to die'

One of the heli-skiiers who survived an avalanche on a South Island mountain range thought he was going to die under the weight of the snow that had buried him.

Melbourne multi-millionaire John Castran was one of a group of three Australian men and two guides skiing in the Ragged Range, near Methven, when the avalanche happened about 1pm yesterday.

A man, believed to be a 61-year-old from New South Wales, died in the skiing accident despite being recovered from the snow only minutes after being covered.

Mr Castran realised he did not have enough oxygen to yell for help while he was pinned under 1.8 metres of snow, he told the Sydney Morning Herald.

"You choke with the snow, you can't breathe, you're suffocating and it's like being poured into plaster of Paris. The only thing I could move was my tongue, to push the snow away from in front of my mouth.

"I thought: 'I've only got a little bit of air here, I've just got to use all the air very, very carefully'. So I just shut myself down totally.

Mr Castran had been on a heli-skiing trip with his son Angus, 23, as well as the Sydney man and two guides from the tour company Alpine Guides.

"It's one of the most spectacular places you've ever seen, absolutely breathtaking country up in the ranges about 6000 to 8500 feet (2600 metres) above sea level," Mr Castran said.

The man who was killed when the avalanche hit about 1pm had said to Mr Castran: "You don't get much closer to heaven than this."

Mountain Safety Council avalanche programme manger Steve Schreiber said the heli-skiing company involved - Alpine Guides - had assessed the avalanche risk was high, but it was not unusual to take people out anyway.

"I think the way they manage the situation is to alter the degree of the terrain," he told Radio New Zealand. They had used the very simple terrain process and were using low-angled slopes.

The group would have been skiing for four of five hours before triggering the avalanche, which was about 200 metres wide, containing 100 metric tonnes of debris.

Mr Schreiber said it was "pretty remarkable" the victim had only been buried for six minutes.

"That's a very, very short time for this kind of deep burial...the reality of it was that the snow itself was very soft so they were able to dig through it very, very quickly."

Statistics showed a person buried for up to 18 minutes had a 93 per cent chance of survival.

He did not know what had caused the man to die but trauma was the primary cause for short burial.

"My understanding is that this gentleman was about 60 years of age and that they went to him very, very quickly," Mr Schreiber said.

"So I suspect that there was something else going on, maybe an underlying illness that was related to this."

After weeks of cold southerly conditions, a change to warm westerlies triggered dangerous avalanche conditions in the Canterbury area, and the council has warned skiers, snowboarders, climbers and trampers to avoid back-country travel until further notice.

- NZPA