A possible sighting of William Kerry Blair's boat has drawn a blank, police say.
Search co-ordinator Sergeant Bill Talbot, of Blenheim, said the sighting on Monday was not Mr Blair's boat.
Mr Blair has not been heard from since he left Erie Bay, in Tory Channel in the Marlborough Sounds, in a 9-metre boat about 4pm on Saturday.
His boat was last seen near Cape Jackson about 5.30pm.
Yesterday police said they were no closer to establishing Mr Blair's destination. Weather and sea conditions had been good, and Mr Blair was considered a capable seaman.
He had enough fuel to navigate the entire New Zealand coastline and police had no indication he wanted to be found.
Yesterday, Mr Blair's family sent out a private plane to search, the second aerial search the family had organised.
The first flight was funded by Mr Blair's neighbour and yesterday's flight was funded by donations from people nationwide, son-in-law Keith Foster said.
The family started a profile on Wednesday on givealittle.co.nz website and by 5pm yesterday had raised $5762. This was enough to send the plane up for a couple of hours. Mr Foster said Mr Blair had everything going for him, with new grandchildren and a loving family.
The family were concerned police were not doing everything they could to find him. "They [police] are using so many resources trying to figure out why he might have left and not enough has been spent trying to find him."
Mr Talbot said police did not search aerially yesterday because they did not know where to look. "Initially this was a search and rescue; it is now moving into a missing person operation."
A signal from Mr Blair's cellphone was picked up off the West Coast side of Farewell Spit on Sunday afternoon, he said. The boat is equipped with a marine radio and a locator beacon.
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