One of the men suffered a suspected broken leg, and the other was thought to have dislocated his elbow and possibly broken some ribs.
"They were pretty happy to see us,'' Mr Johns said.
One of the men is thought to have been at least partially buried underneath snow and was dug out by his companion.
Taranaki Community Rescue Helicopter pilot Sam Richmond said he could see the path the avalanche had followed as he hovered above the mountain.
"It's a bit like the footage you see off TV; it went a good 400m down the mountain, in between a couple of ridges.
"The valley itself was fairly narrow - about 40m - which probably would have concentrated the force of the avalanche. Because of the size of the valley it wouldn't have been easy to escape.''
Mr Richmond said the two men could count themselves lucky.
"I would think anyone who gets caught in an avalanche is probably lucky to get out alive. Certainly, if you get buried then you can't breathe, and if you can't dig yourself out then you're in trouble. If you smack a rock with the wrong part of your body then that would hurt.
"It looked like they were pretty well prepared - they had all the gear, including a survival blanket, which is what we noticed first, glinting in the sun, so we were able to determine their position pretty quickly.''
Flying at such a high altitude had tested the helicopter's capabilities, but conditions had otherwise been kind.
"The engines have got less air to mix with the fuel so they put out less power and also the air's less dense so there's less for the blades to bite in to so control is less firm, it sort of wallows around a little bit, Mr Richmond said.
"We were probably quite lucky in that it was a beautiful days and it was reasonably benign in terms of wind and turbulence.''
After paramedics had been lowered to the men and secured them, a Taupo Youthtown Rescue Helicopter arrived with a winch and lifted them to safety.
They were taken to Taranaki Base Hospital for treatment.
Rescue co-ordinator Sergeant Andrew Ross said avalanches had not been expected this time of year as there was not that much snow on the mountain.
The men may have triggered it by standing on loose snow, but this could not be confirmed.
"They're probably pretty lucky,'' he said.
Taranaki Alpine Cliff Rescue member Jeremy Beckers said it was not a part of mountain one would want to fall down.
"We've certainly picked up a few bodies at the bottom of that slope over the years.''
