The commando killed on Aoraki Mt Cook was the instructor of the training group and noted for his mountaineering ability, twice going close to conquering Mt Everest.
The Australian Defence Force today named him as Gary Francis, known to his friends as "Frankie". The Sydney-based Englishman fell 40m to his death down a crevasse when a pack of snow on an ice bridge collapsed under him yesterday on the Grand Plateau.
Francis, 44, a father of two, was the instructor of the group of nine other soldiers on a two-week survival training exercise on the mountain.
The former Royal Marine was known as one of the world's best mountain experts.
He was not tied to his colleagues when he fell. They retrieved him from the crevasse and attempted in vain to revive him.
Alpine Guides ski guide Ben Taylor said Francis was probing for crevasses on an ice bridge when a square metre of snow collapsed around him about 1pm yesterday.
"When I asked the guys about his experience, they told me he had more experience than the rest of the group combined," he said.
Taylor said the area was reasonably dangerous at this time of year, and he was surprised Francis was not roped to others or wearing a helmet as he probed for crevasses.
"If he was wearing a rope, he may have only fallen two metres, not 40. I wouldn't have been comfortable without a rope on."
The snow bridge was 50 centimetres to one metre thick, and gave way around the soldier into the crevasse, which was "a black hole", he said.
Francis, who was originally from Welling in South East London, previously spent 13 years in the UK Special Forces where he was a Royal Marines Commando Mountain Leader before moving to Australia with his wife in 2010.
A former commando told News Ltd the special forces trainer was “one of the world leaders in his craft”.
“He was the Yoda of climbing.”
In 2006 Francis was part of an Army expedition which aimed to become the first British climbers to reach the summit of Mount Everest via the west ridge. However, they were forced to abandon the attempt due to conditions on the mountain.
That was the second time in three years he had been within hours of the summit.
After the first attempt, he had been awarded the Royal Humane Society team bronze medal for his role in the rescue of another climber, who broke a leg and was suffering frostbite and snowblindness.
Francis was at the time on a joint Marine and Royal Navy expedition to climb the mountain 50 years after it was first conquered on May 29,1953, by Sir Edmund Hillary and Tenzing Norgay.
Francis loved all outdoor activities and regularly posted videos of his action-packed trips on YouTube.
A seven-minute video posted six months ago shows that in 2013 alone he crammed in caving, skiing, rock climbing, kitesurfing, skydiving, paragliding and dirt biking, among other activities.
Senior Constable Les Andrew, of Twizel, said Francis' wife was in Scotland when the accident occurred.
His fellow troops, who pulled him out of the deep crevasse, did not show much emotion shortly after the incident, but were helpful with investigations, he said.
Australian soldiers worked in vain to save the life of their colleague after he fell, but Taylor said he appeared to have major head trauma injures.
The Australian Defence Force said it was investigating the incident, and Francis' death had been referred to the coroner.