Human error and failing to disengage autopilot has been confirmed as the root cause of a New Zealand Navy ship running aground and sinking in the Pacific, a report has concluded.

Crew were unaware the ship was on autopilot mode when they tried to adjust course, and key personnel were distracted and not properly trained; the report found.

The $100 million HMNZS Manawanui motored into a reef off the coast of Samoa at a speed of 11 knots last October.

Defence Minister talks to Ryan Bridge about the report.

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