BBC News - Missing yacht Nina: 'No sign' of Australia-bound vessel 27 June 2013 Last updated at 15:14 A yacht sailing from New Zealand to Australia has gone missing, prompting fears for the seven on board. The crew, six US citizens and one Briton, have not been heard from for over three weeks. They had been journeying from Opua in the Bay of Islands to Newcastle, Australia, abroad Nina, a historic American schooner built in 1928. New Zealand's Rescue Co-ordination Centre said it held "grave concerns" for the crew but remained "hopeful." The Nina set sail on 29 May from northern New Zealand. Three US men aged 17, 28 and 58, three US women aged 18, 60 and 73, and a British man aged 35 were on board. The ship last made contact on 4 June, when it was about 370 nautical miles (685km) west of New Zealand, maritime authorities said in a statement. "Our records show that conditions at the last known position for the vessel... were very rough, with winds of 80km/h (50 mph), gusting to 110km/h (70 mph), and swells of 8m (26 ft)," Kevin Banaghan, rescue mission co-ordinator, said. The New Zealand air force had completed two extensive searches, but "no sign of the vessel has been found," he added. The Nina is made of wood and equipped with a new engine and an emergency beacon which authorities say has not been activated. Mr Banaghan said that Nina's crew had hoped to arrive in Australia by mid-June but weather conditions meant that a more realistic arrival date would be about 25 June. He said there three possibilities as to the fate of the vessel: it had lost communications and drifted off course, the crew had taken to lifeboats or there had been a catastrophic failure and the boat had sunk before anybody had time to react.