Grave concerns are held for the crew of the historic American 21m (70ft) schooner Nina missing en route from Opua in the Bay of Islands to Newcastle, Australia.
The vessel, built in 1928, left Opua on 29 May and has not been heard from since 4 June, when the vessel was about 370 nautical miles west-north-west of Cape Reinga.
There are seven people on board, six Americans (three men aged 17, 28 and 58, and three women aged 18, 60 and 73) and a British man aged 35.
The vessel is equipped with satellite phone, a spot device which allows regular tracking signals to be sent manually, and an emergency beacon. The emergency beacon has not been activated.
After concerns were raised by family and friends, the Rescue Coordination Centre New Zealand (RCCNZ) instigated a communications search on 14 June, using a range of communications methods to broadcast alerts to the vessel and others in the area.
No sign of the vessel has been reported by any other vessel in the area since 4 June.
RCCNZ search and rescue mission coordinator Kevin Banaghan said a RNZAF P3 Orion had completed two extensive searches.
On 25 June, a search area of 160,000 square nautical miles was covered, to the immediate north-north-east of New Zealand, based on the vessel being disabled and drifting.
Yesterday (26 June) a search was completed of 324,000 square nautical miles between northern New Zealand and the Australian coast, based on the vessel suffering damage but continuing to make progress towards Australia.
"Unfortunately, no sign of the vessel has been found," Mr Banaghan said. "Our records show that conditions at the last known position for the vessel, on 4 June, were very rough, with winds of 80kmh, gusting to 110kmh, and swells of up to 8m. We do hold grave concerns for the Nina and her crew but remain hopeful of a positive outcome."
RCCNZ is liaising with the Australian Maritime Safety Authority (AMSA), and will continue to review search options.