Police today confirmed the Civil Aviation Authority is investigating the cause of a 2004 helicopter crash in Fiordland.
Inspector Olaf Jensen said the victims' remains would be formally identified through a forensic process but this could take weeks.
The authority was investigating the cause of the crash and police referred the matter to the coroner, he said.
Police yesterday confirmed the Hughes 500 helicopter wreckage found near the head of Humboldt Creek on Wednesday was that of the aircraft missing for almost nine years.
The helicopter had been carrying the pilot, Campbell Montgomerie, 27, of Waikato, and his passenger, Hannah Rose Timings, 28, of Gloucestershire, England.
The pair have yet to be formally identified. It will be done through DNA.
The families of a helicopter pilot and passenger missing for almost eight years are grieving again after the discovery of helicopter wreckage in Fiordland.
The accident unfolded after the pair flew from Queenstown bound for Milford on January 2, 2004, but set down near the Howden Hut on the Routeburn track in bad weather.
After taking off from the helipad at the hut, they were not seen again. They were declared dead at an inquest in Te Anau in August 2004.
Yesterday morning, seven police search-and-rescue specialists and two personnel from an Alpine Cliff Rescue team were flown by helicopter to the foot of three sheer rockfaces, at an altitude of 1340 metres, just above where the first traces of the wreckage were found.
Parts of the helicopter were seen among rocks and scrub just above the snowline, and showed the extent of the accident impact.
Extensively damaged sections of the helicopter, barely visible yesterday from the air because of their similar colour to the scrub and rocks, as well as intermittent cloud, were scattered throughout the rugged terrain.
The surrounding terrain was so difficult that the two alpine cliff rescue team members were unable to be seen easily from the helicopter without high-visibility gear, after they were taken to the site.
The wreckage was spotted about 4pm on Wednesday by Queenstown-based helicopter pilot Brendan Hiatt.
Hiatt said he was on his way back to Queenstown after picking up two American couples who had been on a cruise around Milford Sound, when he saw something below.
"I just spotted something glinting that just didn't look quite right among the snow, so I said 'We'll just take a look'.
"It's happened before, where you see a glinting rock or something that you go in closer for a look at.
"We got close and it was pretty evident what it was."
The helicopter got within about 20m of the wreckage. Those on board could see a section of the tail and a rotor blade, he said.
"It was destroyed. It's been a very, very violent impact," he said.
The remote location was likely the reason why the helicopter had not been found.
"The lower part of the valley is pretty bushy so the access in there would be pretty difficult.
"That's probably why nobody's come across it before.
"There's plenty of them [missing aircraft] around, though, so you're always looking, I guess."
Civil Aviation Authority spokesman Mike Richards said yesterday that two police disaster victim identification officers had been at the site all day yesterday photographing and taking video of the scene.
The images would be passed on to the authority for review to see if there were any obvious indicators of equipment or mechanical failure which might result in a key safety lesson.
However, it looked like the wreckage was the subject of a fire and that, coupled with sustained exposure to extreme weather conditions since 2004, would make it difficult to assess, he said.
- Fairfax Media
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