AN INTERIM report into the grounding and sinking of HMNZS Manawanui has attributed the loss to human error.
A dedicated Court of Inquiry, the findings of its interim report released today (29 November), found the crew had not turned off the ship’s autopilot.
Royal New Zealand Navy ship Manawanui ran aground off Samoa on 5 October 2024 while conducting survey operations. It sank the following day after a series of catastrophic fires. All 75 people on board were rescued.
The findings detail how the ship’s crew had attempted a routine turn to starboard within the survey area. They then attempted to turn off the initial 340-degree course towards an easterly course, but the ship did not respond as intended.
Manawanui left the approved survey area, and the crew conducted further actions they believe should have stopped the ship.
But the ship did not slow or stop. Instead, it started to accelerate towards the reef, grounding for the first time around 18:17 at a speed of more than 10 knots. It then travelled about 635 metres before becoming stranded, grounding multiple times along the way.
Full control of Manawanui’s propulsion system was not regained until 10 minutes later, at 18:27, when the ship’s autopilot was disengaged.
“The direct cause of the grounding has been determined as a series of human errors which meant the ship’s autopilot was not disengaged when it should have been,” RNZN Chief of Navy Rear Admiral Garin Golding said.
Rear Admiral Golding established the Court of Inquiry to investigate the circumstances of the incident.
“The crew did not realise Manawanui remained in autopilot and, as a consequence, mistakenly believed its failure to respond to direction changes was the result of a thruster control failure,” he said.
“Having mistakenly assessed a thruster control failure, standard procedures should have prompted ship’s crew to check that the ship was under manual control rather than in autopilot. This check did not occur.
“Remaining in autopilot resulted in the ship maintaining a course toward land, until grounding and eventually stranding.”
Further details are still being worked out as part of the wider Court of Inquiry process, which is due to conclude in the first quarter of 2025.
Those details should determine why the autopilot incident happened and “what would come next in terms of lessons learned”, according to Rear Admiral Golding.
He said because human error was identified as the cause, a separate disciplinary process would be necessary once the Court of Inquiry had concluded.
As well as the primary cause, there were also a number of identified contributing factors leading to the ship’s grounding, which will be considered in more detail during phase two of the Court of Inquiry.
“To provide some immediate assurance, we have conducted a series of audits in the fleet and looked to implement initial lessons identified from the interim report around training, risk management, and improving relevant orders, instructions and procedures,” Rear Admiral Golding said.
He assured the public of New Zealand the navy would learn from the situation.
“In this situation, we thankfully did not lose any lives, but lives have been affected nonetheless, and we continue to support and work closely with those who were onboard Manawanui on that day.”
Rear Admiral Golding said he was grateful for the support from the Transport Accident Investigation Committee, the Royal Australian Navy and Royal New Zealand Air Force for their support in the investigation. The New Zealand Defence Force also thanked Samoa for its support.
