An Air Force Orion is searching for 29 missing fishermen after a long liner was found burnt out but with no one on board.
The boat, which had 29 Taiwanese fishermen on board, was found by a Korean fishing boat in the area of the Pacific Ocean administered by Fiji.
Royal New Zealand Air Force commodore Gavin Howse said the boat's last contact was on October 28 but the Air Force did not receive details of the missing boat until Monday.
He said a search of the boat showed the three life rafts and a rescue boat were missing and it is hoped that the 29 crew abandoned ship in the life rafts.
Mr Howse said the search team can locate missing boats in bad conditions but this mission will be a test.
He said the Orion left New Zealand yesterday and will search 54,390 square kilometres of Ocean.
"The plan is to give the aircrew three full days of searching a vast area that has been calculated by us and the RCC [Rescue Coordination Centre]," Mr Howse said.
He said the Orion would return on Saturday.