Three crew members aboard a helicopter that crashed off the New Zealand coast while on their way to a medical evacuation from a fishing boat have been found alive on a remote island.

“We are elated to hear they are safe, this is the best news, it is like 10 Christmases have come at once,” said Lloyd Matheson, the operations manager of the helicopter company the crew work for.

Rescue Coordination Centre duty manager Kevin Banaghan said the trio was found on Tuesday in their survival suits walking on a beach on uninhabited Auckland Island, some 500 kilometres south-west of Invercargill, where they flew from.

Mr Banaghan said the outcome was great news – although he did not yet have all the details about what had happened.

Missing helicopter crew found safe and well on the NE side of Auckland Island (500km south of NZ) wearing their cold water immersion suits. Radio contact was lost at 7.37pm Monday evening. The map shows search areas and flight paths.https://t.co/49vuh6y2uS pic.twitter.com/EHO3dAQpXu

— Maritime New Zealand (Nō te rere moana Aotearoa) (@MaritimeNZ) April 23, 2019

The New Zealand Herald named the three men as pilot Andrew Hefford, winch operator Lester Stevens, and paramedic John Lambeth. All are staff of Southern Lakes Helicopters.

Mr Matheson told the paper he was supposed to be on board the rescue flight, but had swapped places with Mr Stevens at the last minute.

The final contact with the Southern Lakes Helicopter was at 7.37pm local time on Monday. It dropped from radar soon after.

A New Zealand Air Force P-3 Orion plane searched unsuccessfully for the helicopter overnight, before a fishing boat found a side door on Tuesday.

The rescue teams  included Sir Richard Hayes, Southern Lakes Helicopter’s chief executive and chief pilot.

-with AAP