An independent commission investigating the Enchanter sinking aims to identify the causes and prevent a similar tragedy happening again. Photo / Supplied
An independent commission investigating a boating tragedy off North Cape says it will examine every detail and take as much time as it needs to ensure closure for the victim's families.
Five people died and another five were plucked alive from the sea when fishing charter boat Enchanter capsized atMurimotu, off North Cape, in ferocious conditions on Sunday night.
Separate investigations by police, the Transport Accident Investigation Commission (TAIC) and Maritime NZ are already underway, each with a different objective. WorkSafe may also investigate.
The role of TAIC, an independent commission of inquiry investigating aviation, marine and rail accidents, is not to find out who's to blame, but to identify the causes and reduce the chances of similar tragedies happening again.
TAIC chief investigator Harald Hendel, from Whangārei, said yesterday's sinking of the Enchanter while it was being salvaged could complicate the investigation.
"But the investigation involves many lines of inquiry. Having the vessel would be just one of those. If the vessel is in a certain depth of water and there's still a need to get evidence, that will increase the efforts required."
TAIC staff would interview survivors as soon as possible, while their memories were still fresh, as well as look at the vessel's documentation, surveys, equipment and licences.
The interviews were voluntary, but once TAIC's purpose was explained, people were cooperative and willing to share, Hendel said.
The evidence gathered by TAIC was protected, which meant it could not be used against anyone in court.
TAIC also had a protection order on the vessel to preserve any evidence. Any salvage attempts had to be conducted in consultation with the commission.
Once the draft report was ready it was sent to everyone who had taken part, giving them a chance to comment on the findings before the final report was released publicly.
The whole process could take from six months up to three years for the most complicated international investigations.
"It really depends what the early days of evidence gathering bring. From that you identify what you're going to investigate and what depth will be involved," Hendel said.
People connected to the vessel's crew have told the Advocate they believed the tragedy occurred when a "rogue wave"' took off the top of the Enchanter's cabin, destabilising the vessel.
Hendel, however, said TAIC did not speculate or comment on potential causes until the final report was complete.
"It's about being thorough, gathering information, taking the time needed to go through the details and not making judgments at an early stage. Otherwise we wouldn't do justice to those who have passed away, or give closure to families seeking to understand what happened."
It's not the first time TAIC has investigated a boating accident near North Cape.
In April 2008, the fishing charter vessel Pursuit was grounded on rocks at Murimotu, close to where the Enchanter came to grief.
A helicopter was unable to winch the five passengers and two crew to safety because of extreme weather. No one was hurt, but the Pursuit was badly damaged.
The Whakatāne-based vessel was on its way to the Three Kings Islands.
In August 2004, the fishing vessel Iron Maiden foundered on Pandora Bank, southwest of Cape Reinga, with the loss of its two crew. The boat was on a delivery voyage from Mangōnui to Raglan.
In 1996, the fishing trawler San Manukau capsized north of Cape Karikari. One deckhand died.
After each investigation TAIC issued a number of recommendations.
In the case of the Pursuit, that included advice about anchoring in poor weather, the danger of not maintaining an anchor watch during adverse weather, and compliance with manning requirements.
Maritime NZ would not comment on its investigation into the Enchanter yesterday.