Two Auckland climbers who died after becoming stranded near the summit of Mt Taranaki in freezing conditions on Labour weekend last year died of hypothermia, a coroner has ruled.

Rescuers spent two days trying to reach Nicole Sutton, 29, and Hiroki Ogawa, 31, with one group coming within 150m of the couple, but "horrific" weather conditions forced them back.

When search teams finally reached them on the third day up the mountain, on Monday, October 28, 2013, Dr Ogawa was already dead. Ms Sutton died two hours later, in the arms of rescuers.

Today Coroner Chris Devonport released his findings into their deaths, saying there were "many lessons to be learned".


"In general they include to plan according to weather forecasts; to monitor changing weather conditions; to have a plan including when to be off the mountain; to be prepared to have to stay for longer than anticipated in weather more adverse than anticipated," Mr Devonport said.

However, he also highlighted a number of other recommendations and comments in relation to the search and rescue operation, including bringing a search team from the Ruapehu Alpine Rescue Organisation (Raro) to New Plymouth by helicopter. The team was instead forced to drive the four-hour journey, following lengthy discussions about transportation.

It was estimated this set the search and rescue operation back by 12 hours.

The issue had been a point of contention for the Sutton and Ogawa families at the inquest in October.

"I consider that an appropriate action at 10am on Sunday, October 27, 2013 was for the [RNZAF] Iroquois to commence transporting Raro members from National Park, as this was the time the Raro members commenced departing by vehicle," he said.

"Had that occurred, valuable hours may have been saved in reaching Dr Ogawa and Ms Sutton. Whether that would have resulted in a different outcome is unknown."

The Sutton family said they did not want to comment on the finding.