Graham Garnett, 66, was meant to return on 30 December. Photo: Supplied / NZ Police
Despite five helicopters aiding in the search for an overdue tramper in the Kahurangi National Park, there is still no sign of him.
Graham Garnett, 66, went tramping in the Baton area of the park and was expected back on 30 December.
He did not return and was reported missing.
Sergeant Jonny Evans of police search and rescue said an Airforce NH90 helicopter was one of the helicopters used.
"Two specialist canyon teams searched the steep terrain with specialised equipment and a field team also scoured the search area.
"There is still no sign of Graham and the search will continue tomorrow."
Radar technology that was being used to search for Garnett has long been used on ski-fields, but is now increasingly also used for other searches, the Mountain Safety Council said.
Mike Daisley, chief executive officer of the Mountain Safety Council, said the radar picked up on people with the specific Recco strips in their gear. The system had long been used in ski fields and alpine environments, particularly to find people caught in an avalanche, he said.
"Within New Zealand, using it in a wider land based [search], that's a fairly new thing.
"That's mainly based on the different types of clothing and equipment manufacturers now putting this in more general items, rather than just in very specialist alpine clothing."
Daisley said the radar would easily pick up the gear with the specific RECCO strips, but could also pick up other metal.
"Small parts of backpacks have often got little pieces of aluminium and other metals, or even in your rain hood of your rain jacket, and they may be detected. That's why police are asking other people to stay out of the area."
Evans said police wanted to hear from anyone in the area from 26 December - particularly around Flanagan's Hut - who had yet to speak to them.
"Any sightings or information can be reported at 105.police.govt.nz, clicking 'update report', or by calling 105.
"Please use the reference number P064981672."
Drone used in second search
Another search is underway near Lake Ōhau in the Mackenzie Basin for 20-year-old Connor Purvis, who has not been seen since he went to climb Mt Huxley on Tuesday last week.
Connor Purvis. Photo: Supplied / NZ Police
Police said they would be deploying a drone to assist search efforts, as long as weather conditions held.
Daisley said drone use was also increasingly common by LandSAR and police in searches.
"Overseas they have been used for some time, but as drone technology has become a bit more approachable in price and the range of this equipment has increased, it is growing in its use."
Drones could be easier to deploy than a small plane or helicopter, but still had limited range and were much more impacted by the weather conditions, he said.
Daisley said the main bit of advice for people heading out on tramps, particularly for those doing longer trips, was to take some form of emergency communication device and not just rely on cell phone technology.
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