Court of inquiry finds "series of human errors" caused HMNZS Manawanui grounding in Samoa

A Court of Inquiry that was stood up following the grounding of the Royal New Zealand Navy dive and hydrographic ship HMNZS Manawanui in Samoa on October 5, 2024, determined that the incident was the result of human error.

"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," said Rear Admiral Garin Golding, who stood up the Court of Inquiry in order to understand the facts of what occurred.

"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."

Rear Admiral Golding said that, 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, and remaining in autopilot resulted in the ship maintaining a course toward land, until grounding and eventually stranding.

Rear Admiral Golding said why the incident happened and what would come next in terms of lessons learned were still being worked on as part of the wider Court of Inquiry, which was scheduled to be completed in the first quarter of next year.

Although human error has been identified as the cause, a separate disciplinary process would need to be commenced once the Court of Inquiry concludes.

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," added Rear Admiral Golding.

The Court of Inquiry investigation was undertaken with support from the New Zealand Transport Accident Investigation Commission, the Royal Australian Navy, and the Royal New Zealand Air Force.