Yesterday morning he was winched down onto the mountain, from an air force helicopter, and helped recover the bodies of Nicole Sutton, 29, and former University of Wollongong student Hiroki Ogawa, 31, who died after they spent two nights in a snow cave. The recovery operation took place in near perfect conditions.

It was "a beautiful morning up there, not a breath of wind", Johns said.

But it was a different situation when he and his team started out just after 1am on Sunday - into driving wind, horizontal sleet and rain.

Massive gusts made walking difficult, he said. They got to nearly 2200 metres. The climbers were at about 2400 metres.

"We were the next valley over, but getting close to that altitude. They had given us a rough coordinate that was pretty close."

The rescue team was getting pounded by sleet, he said.

"So one side of your face was going numb. By that stage we were so covered in ice everything was starting to freeze up. It wasn't particularly pleasant conditions."

It got so bad that just after 3.30am they made the gut-wrenching decision to turn around and go back down.

"It weighed on everyone's mind. We discussed it as a team, but our safety came first and we all agreed we were at the point it was starting to get dangerous."

The team, who were carrying 20kg packs, were hoping the two climbers had dug in and were well secured in their spot, Johns said.

"They were probably in a better position than we were when we turned around.

"We discussed digging a snow cave as well and staying up there, but we thought, 'What are we going to achieve?' We are going to be cold and wet and miserable and no good to anybody. We'd be better off coming back and regrouping and trying again."

There was a wind chill factor of -15 so it was "pretty cold".

Johns got back to the base at 6am. Teams were still assembling and the fourth team to go up made it to the climbers who were dug in just below the rim of the crater.

Normally it is possible to get right inside a snow cave and get out of the weather, he said.

"But they had just managed to dig a slot in the snow and get into it.

"Considering how hard it would have been up there - the ice gets really hard especially that high - it would have been a big effort for them to do what they did. So they did really well."

Johns spent Monday with the crew of an air force helicopter trying to get on the mountain, but it was too windy. The wind was still howling when the rescue team found the missing climbers about 7.30am Monday.

"That's why they made the decision to leave them behind and get out of there."

The search teams will be "going through a bit of victim support, especially the guys who found [the climbers]."

The police also provide support and there will be a formal debrief, he said.

"The guys don't like talking about it. But it was a big operation, especially with people getting so close and having to turn back. There are some people out there with mixed emotions - if they'd managed to get on a bit further ...

"But at the end of the day all the teams made the right decision. No searchers got lost or injured."

The search involved more than 30 volunteers and Mr Johns estimated they would have spent 2000 hours during the rescue attempt.

"The incident management team ran all the time. We don't usually do that. Often we shut down overnight, but because teams were still going up at all hours, we had to man it the whole time.

"If there were no volunteers there would be no search and rescue in New Zealand."

Taranaki police Senior Sergeant Thomas McIntyre, who was part of the incident management team, said the volunteers had given up their Labour Weekend to help.

The 20 search and rescue people from the Ruapehu Alpine Rescue Organisation had driven over from National Park.

"Without [the volunteers] we don't have a search and rescue capability. We rely on them to get the job done."

LandSAR helped with administration and was following the tracks of the climbers who walked out around noon on Sunday.

"Arec [Amateur Radio Emergency Communications] came in and operated all our search and rescue radio. And the Taranaki rescue chopper provided invaluable support."

The air force and the police were also involved in the rescue, McIntyre said.

"It was a big operation. There was a lot of people to manage and mitigate the risk to them, as well as rescue the people who are in trouble."

Fairfax NZ