A fresh account of White Island helicopter pilot Brian Depauw's life-saving instructions to his passengers on the crater shore reveals the group held their breath for two minutes underwater as the ash cloud hovered above.
Depauw was a pilot for Air Safaris helicopter tours, and landed his helicopter on White Island shortly before the eruption at 2.11pm on December 9 last year that killed 21 people.
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Depauw's instructions to his four German passengers to "jump into the water" at the sight of the huge plume of volcanic ash rising 3600 metres into the sky has been widely praised.
But new details of the moments following the group's jump into the Pacific Ocean have been reported in US publication Outside.
In the article published on April 15, it revels Depauw saw a dark wave of ash roll across the ocean's surface after he had jumped beneath it, with two of his passengers.
His other two passengers did not make it into the water, and suffered severe burns.
Depauw relayed his thoughts to Outside as he jumped into the ocean: "This is it. There's no surviving this."
Depauw and the two passengers who escaped unharmed said they were in complete darkness for about two minutes, at which point some light began to return.
He told the Outsider that once he surfaced, the water around him was layered with a dirty yellow dust that reeked of sulphur.
But behind the initial wave of ash, the air was beginning to clear.
After surfacing, Depauw and his passengers swam to shore, as the Phoenix cruise ship skippered by Paul Kingi raced in to the jetty where burnt tourists were now congregating.
US woman Ivy Kohn Reed, 51, from Maryland, north of Washington, DC, was one of the passengers on the island during the eruption who appeared, hands on her hips, waiting to board.
A man was also sitting down on the jetty.
Eventually it could be seen that the group's clothing was covered with ash, and people's limbs appeared blackened.
Once aboard Kingi's boat, Kelsey Waghorn was seen to be covered in ash and moving unsteadily. Jake Milbank was also coated and lying in the bows, staring up at the sky.
In a handful of trips around the island, Kingi and his crew picked up 25 passengers including Depauw and his four clients.
As the Phoenix was preparing to return to Whakatāne, Kingi switched boats to the fellow cruise ship Te Puia Whakaari to make a final sweep of the shore.
Walking into the crater, Kingi saw a figure stumble out of the ash which turned out to be Jesse Langford, 19, who had been with guide Hayden Marshall-Inman's group inside the caldera with his father Anthony, 51, mother Kristine, 45, and sister Winona, 17.
Langford had managed to stumble out of the crater but every part of him appeared burned to Kingi.
Every other member of Langford's family died on White Island.
Carefully, Kingi assisted the teenager into the dinghy he had crossed to White Island in and quickly returned him to the Te Puia Whakaari cruise ship, which raced back to Whakatāne.
At that point Kingi had got word that another cruise ship, the Peejay IV, was returning to the island after disembarking its uninjured passengers at Whakatāne.
Kingi elected to stay behind on the ash-covered volcano and continue to search.