He believed the men had taken a wrong turn on their way down the mountain and had not seen the 15-metre drop until it was too late, though one man was able to stop before he reached the cliff edge.
Four of the men tumbled over the drop then slid on ice about 200 metres to the Mangaehuehu Glacier below, which sits at an altitude of more than 2000 metres.
The alarm was raised by alpine rescue staff and several rescue helicopters responded.
A 22-year-old man from Clevedon, in Auckland's south-east, was airlifted to Middlemore Hospital with serious spinal injuries, while two others were flown to Rotorua Hospital, one suffering a head injury.
A fourth man was uninjured after the dramatic fall.
Mr Every said the Greenlea Rescue Helicopter was unable to land on the steep slope, so "hover-loaded" the three injured skiers and snowboarders one at a time before flying them to the Turoa Medical Centre in three separate trips.
The 22-year-old was later picked up by the Lowe Corporation Rescue Helicopter and delivered to Middlemore Hospital about 5pm. He was conscious at the time.
The two others were transported to Rotorua.
Mr Every said he believed the group was initially made up of about five Auckland men aged between 20 and 40, who were forced to turn back from their hike to the summit amid deteriorating visibility.
One of the men who slid over the cliff was uninjured, one had "a few knocks to his head" and another was "walking wounded", Mr Every said.
"They slid an awfully long way - a couple of hundred metres - before they stopped.
"They were well and truly outside of the ski area boundary but the ski patrollers did a bloody marvellous job of getting to them and helping co-ordinate the recovery."
Mt Ruapehu Ski Areas customer relations manager Annah Dowsett could not comment on the latest incident because it happened outside the skifield boundary of the.
"When you leave the ski area boundary there are very very clear signs. You have to go under a rope to get out," she said.
Other Ruapehu accidents
• A 25-year-old male climber suffered serious head injuries after he slid 300 metres in an area known as Grand Gully in July. He was part of a group of climbers who were climbing the Pinnacle Ridge, Whakapapa. He was airlifted to Waikato Hospital by the Westpac Rescue Helicopter.
• A 23-year-old female from the same climbing party became stuck on the top of the Pinnacles and was unable to continue. She was retrieved by Taupo's Greenlea Rescue Helicopter.
• A novice skier tumbled 35 metres into the crater of Mt Ruapehu after he attempted to ski inside it after a few runs down Turoa Skifield in August. The man was tired, exhausted and cold after the fall and said he would have died had two skiers not come to his rescue.
- additional reporting: Lincoln Tan, Anna Leask
