We're still hopeful and we're still out there looking.''
The weather during the search had been "pretty good'', he said.
Paul Booij, Hevilift's Group Managing Director, said a specially equipped Dornier 328 fixed-wing aircraft had already been used to conduct electronic surveillance.
A helicopter with a fixed magnetometer, which disturbances in the earth's magnetic field caused by large mineral deposits, was to be used in the search today.
"An aircraft the size of a Bell 206 has enough ferrous material in it to show up and be 'seen' by one of these machines,'' Mr Booij said.
Ten years ago, Mr Annan's brother Matthew was killed in a topdressing plane crash in Australia, Central Otago Flying Club president Russell Anderson said.
He had known the family when they lived in Alexandra.
"It's cliche I know, but no parent should have to bury their children [but sometimes] it's the way the cards get stacked against them unfortunately.''
Flying ran in the family, as Mr Annan's late father, Bill, was president of the Central Otago Flying Club for more than six years. He was also made a life member of the club.
Mr Anderson said his hairs pricked up on Saturday when he heard news a New Zealander was one of those on the missing helicopter.
"I know quite a few pilots, it being an aero club, there's a lot of Alexandra lads who have gone on to be rotary wing pilots around the world.''
"Your heart goes out because of the not knowing and the waiting and the ripple effect through the whole community, both countries, Australia and New Zealand.''
Mr Annan, who lived with his partner in Australia, had been flying for about 30 years and was a very experienced pilot.
"He'll be very well respected within the organisation, the community, the flying fraternity, his wealth of experience.''