Bombshell finding in report into $130m naval ship sinking

A New Zealand Navy ship sank off Samoa because the crew did not realise its autopilot was still turned on before it ran aground, a Court of Inquiry has found.

The HMNZS Manawanui, which cost NZ$147m (A$130m), ran aground on a reef on the southern side of Samoa on October 5 before catching fire and ultimately sinking.

All 75 crew on board were evacuated safety but it was the first time New Zealand had lost a ship since World War II.

According to a Court of Inquiry report, human error was behind the accident after the crew believed that the ship had suffered thruster control failure when in fact the autopilot was still engaged.

“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,” Rear Admiral Garin Golding said.

“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 that the crew should have checked whether the ship was still on autopilot.

“This check did not occur,” he said.

“Remaining in autopilot resulted in the ship maintaining a course toward land, until grounding and eventually stranding.”

Why the mistake was made will be further examined by the Court of Inquiry next year.

Disciplinary proceedings will begin following the completion of the second phase of the inquiry, the NZ Defence Force said in a statement.