Australian climber Terry Harch's rescue was 'touch and go'

Rescuer's say without him waving, an Australian soldier trapped on a mountain for nearly a week may have been missed.

Australian climber Terry Harch (centre) has been rescued from a New Zealand mountain. Source: Supplied

An Australian soldier rescued from a New Zealand mountain after nearly a week in the cold may have never been spotted had he not waved to a passing helicopter, his rescuers say.

Lieutenant Terry Harch was airlifted from Mount Aspiring in the South Island and to a hospital on Friday evening as helicopter pilots capitalised on a small gap in harsh weather that had been stalling rescue efforts for days.

Dunedin Hospital said it was unable to provide details of Lt Harch's condition on Saturday due to a family request for privacy, but he was earlier reported to have had mild frostbite on his hands, and been dehydrated and exhausted when found.

Rescuers at the time described him as being in good spirits and communicative and said it was "extraordinary" Lt Harch was standing and waving when he was first spotted on Thursday night.

Cliff rescue team leader Davie Robinson told the Otago Daily Times that gesture may have saved the climber.

"Without that we probably wouldn't have found him that evening, because it was getting dark," he said.

A team of four with supplies spent a night with Lt Harch and hoped on Friday for a window in the weather.

"He had a tough night," Mr Robinson told the paper.

"Our main job was to reheat Terry and prevent further injury ... There wasn't much we could do for that pain at that point."

Lt Harch used his military training and mountaineering skills to dig himself shelter in the snow and survive days of freezing temperatures, strong winds and heavy snow until help reached his beacon, rescuers say.

An experienced climber, he had previously scaled Mount Cook for charity.

Arriving at the national park last Friday, he is thought to have left his heavier gear behind to make a quick ascent - not unusual practice - before being caught out by the weather.

More than 30 people have died around the popular national park surrounding Mount Aspiring in the past decade, with mountain safety groups frequently warning of the risks posed by New Zealand's rugged landscapes in winter.