A maritime historian says a lack of training and expertise with the HMNZS Manawanui’s autopilot and propulsion systems caused October’s accident. 

The Royal New Zealand Navy ship, a specialist survey and dive support vessel, struck a reef on the evening of Saturday, October 5. It began to list and Commander Yvonne Gray gave the order to abandon ship. 

A fire broke out in the engine room and the $100 million vessel sank on the Sunday morning off the south coast of the Samoan island of Upolu. 

US Merchant Marine Academy adjunct professor Dr Salvatore R Mercogliano told Newstalk ZB that Manawanui’s azipod propulsion required a lot of training to be proficient in its use. 

Defence Minister Judith Collins and Chief of Navy Rear-Admiral Garin Golding address the media about the findings from an inquiry into the HMNZS Manawanui sinking. Photo / Alex Burton 

“It also has a sophisticated autopilot system that requires familiarity with it,” he said. 

“It appears from the interim report given by the admiral in charge of the Navy, that there was a lack of knowledge in how to effectively shift from autopilot back into manual control.” 

Following the release of the interim Court of Inquiry report last month, Chief of Navy Rear-Admiral Garin Golding said the direct cause of the grounding was because of a series of human errors, resulting in the ship’s autopilot “not being disengaged when it should have been”. 

“Having mistakenly assessed a thruster control failure, standard procedures should have prompted the 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.” 

Royal New Zealand Navy divers survey HMNZS Manawanui off the southern coast of Upolu. Photo / NZDF 

Mercogliano said before Manawanui was transferred to the Royal New Zealand Navy, it had a sophisticated autopilot system that allowed the crew to navigate where they wanted. 

“When the ship was converted, there was a question whether the full dynamic positioning system carried over or was there a modified autopilot system on board,” he said. 

“During survey operations, you really want it to be on autopilot to have the straightest course possible. On an autopilot system, it’s almost like having a car with automatic lane changes.” 

Mercogliano said the findings in the report showed a clear lack of familiarity with the system. 

“When you’re operating close to a reef, familiarity was really key. I’m at a loss to understand why they didn’t just stay in manual mode until they were on a course setting they wanted to.” 

Mercogliano said he wouldn’t call the Manawanui’s grounding humiliating but an accident. 

“Accidents will always happen. As long you have humans interfacing machinery, especially at sea, you’re going to lose vessels,” he said. 

Defence Minister Judith Collins said “we were all terribly disappointed in what happened”. 

She said the Navy had since acted professionally, and New Zealanders could have full confidence the Navy and Defence Force were not shying away from the incident and had stepped up to the mark in taking the incident seriously.