In an incredible tale of survival, three men have beaten the odds and survived a horror helicopter crash off the coast of New Zealand.

The three pilots from Southern Lakes Helicopters — who are some of the country’s most experienced rescue crew members — crashed their aircraft 450km off the coast of Invercargill on the South Island just before 8pm on Monday night.

Pilot Andrew Hefford, paramedic John Lambeth and winchman Lester Stevens swam 20 minutes in the dark, freezing water to a beach on one of the subantarctic islands, 450km south of New Zealand.

Their helicopter had crashed on descent into Enderby Island, where they planned to spend a night before performing a medical evacuation from a fishing vessel the following morning.

“The way the weather conditions were, we chose to fly to Enderby islands last night in preparation for a winch off the vessel this morning,” Lloyd Matheson from Southern Lakes Helicopters told NewsHub of the intended rescue mission.

But at around 7.57pm, the two-engine helicopter lost radio contact near Yuke Island and plunged into the ocean. In response, a search mission was launched to recover the wreckage.

In an interview with the New Zealand Herald, Sir Richard Hayes — CEO of Southern Lakes Helicopters — said the ordeal, involving a search party of helicopters and five fishing boats, was the “worst night” and “worst day” of his life.

“The whole trip to the Auckland Islands yesterday was virtually flown in silence,” he said of the mission.

That was until the moment he saw his three crewmen on a beach having miraculously survived the horror helicopter crash the night before.

“We were expecting the worst, and that turned 180 degrees and we were absolutely elated to see three orange-clad figures on the beach,” he explained.

The men were in their cold water immersion suits, typically designed to maintain a comfortable body temperature in conditions as low as -30C.

They had made it to the closest shore despite the darkness and with no lights on the island to guide their way. It was a cool 10C at the time they were believed to be in the water.

It was not known how far they swam, but they were picked up at Ranui Cove on the main island, between 2km and 3km from the helicopter wreckage.

Mr Hayes, who has over 40 years’ experience as a helicopter pilot and flown over 30,000 hours, said it was a particularly emotional operation given those involved.

“We have done hundreds of rescues over the years, but when it is close to home, it really is hard, and yesterday was the hardest,” he said.

“These are all key personnel that have worked with us for years, and the thought that we had lost them was a pretty hard pill to swallow, but it was certainly a great trip home.”

Mr Hayes said it was about a three-and-a-half hour flight from Invercargill, but they did not spend much time down there as they spotted the crew on first approach.

“On first approach we could see them on the beach. One of my crewmen spotted them,” he said, noting two of the men had been knocked when the helicopter had crashed.

“They were wet and cold, had spent a night out in the bush. A cold front came through, with wet and squally conditions. They were glad to have a cup of coffee and a bite to eat.”

Hayes said their survival came down to training and instinct.

“Lester was knocked out on impact and had no idea how he extracted himself from the aircraft, maybe it goes back to the HUET (helicopter underwater escape training) required to do any oceanic flights.

“He came to in the water, and everyone got out as the helicopter was still floating, leaving them to a 20-minute swim to the shore.

“I believe the training, any training be it flying or emergency, does kick in, and in the case of Lester and even Andrew, who was knocked out for a short period, survival instinct and training kicks in.

“It is just great to have them back home.”

— with the New Zealand Herald