A speed flier rescued in the pitch black after crashing into a canyon at Temple Basin says he knows how lucky he was to get out with only scratches and a sprained thumb. 

American engineering student AJ Dayvie, 25, was pulled off the side of a mountain in the early hours of Monday morning after a 12-hour rescue effort.

Dayvie had already done one speed fly - much like paragliding on skis - from the top of the moutain to the huts about midday on Sunday, and it had gone off without a hitch.

With his friends deciding to head back to Christchurch after a weekend of skiing about 4.30pm, Dayvie decided to do a final speed fly down the mountain, saying he would meet them at the carpark.

He knew there was a risk, but it was still light, the air temperature on the moutain was yet to drop and the flight would last only a few minutes.

But as he flew down into the valley below the huts, he lost sight of power and tow cables running up the side of the valley, which he had planned to fly under.

When he saw them again, they were right in his path less than 20 metres away.

Dayvie took evasive action, attempting to do a series of steep turns to lose height quickly and get below the cables.

Picking up speed, he started to lose control.

"I thought, well this is it. I'm about to be seriously injured."

On the last turn he slammed into snowy scrub on the side of the mountain, he guesses at 15-20kmh.

Briefly knocked unconscious, he awoke disorientated and confused.

"I was in a very bad spot, very steep," he said.

Pumped with adrenalin, he gathered up his gear and started hiking up the mountain in his ski boots.

"In my mind I was thinking, I've got to get out of here," he said.

"The sun was going down, people would be looking for me. I was in a spot where you couldn't see the road ... where no-one would find me, at least for a very long time."

About 50 metres up, he reached a plateau and could go no further as the 150 metres of cliff up to the huts was too steep.

"I went into 'sit tight' mode. I had enough room to pace and keep warm and used my wing [parachute] as a sleeping bag."

His friends waiting at the car park raised the alarm. Some hiked up the valley until they were in shouting distance.

A rescue helicopter was sent in from Greymouth, arriving about 9pm.

In the dark, Dayvie used his lighter to set fire to a bush to try to show them where he was. 

Unable to winch him up due to the cables, a volunteer Cliff Rescue crew from Christchurch was called in.

Another rescuer from Arthurs Pass got to Dayvie about 12.30am on the second attempt to get down from the huts.

"It was absolutely fantastic to have some company at that point," Dayvie said.

Cliff Rescue arrived a few hours later - one of the crew abseiling down with coffee and a sandwich.

After setting up a pulley system at the top of the cliff, the crew at the top winched Dayvie out.  

He said it was slow going, taking about an hour to reach the top.

"It felt great to get out."

He was airlifted to Arthurs Pass, arriving about 4.30am - 12 hours after he first took off - then on to Greymouth Hospital.

Given the all clear, his friends drove him back to Christchurch on Monday.

Dayvie said he felt "really lucky'', and was thankful for the efforts of rescuers.

If he had hit the cables, he would have been unlikely to survive. If his parachute had hit the power lines the arcing could have caused his parachute to catch fire and he would have "dropped like a stone" down the valley.

"I feel really lucky. It could have been a lot worse that it turned out to be," he said.

Cliff Rescue volunteer Jason Tweedie said the calm clear weather and full moon made the rescue a lot smoother than it could have been.

Dayvie said if he could go back to the moment he took off, he would never have flown.

However, his brush with death had not put him off the sport. He had done about 100 flights before and had "close calls, but nothing like this."

"When you get into these extreme sports, you always realise there are some risks involved," he said.

"If I knew the visibility was going to be poor in the valley, I wouldn't have flown. The wires were smaller than I expected and were hard to see. That was the main problem."

- © Fairfax NZ News