THE 21 June grounding of Cook Strait ferry Aratere occurred because no-one on the vessel’s bridge knew how to de-activate the incorrectly-set autopilot, according to leaked documents circulating in NZ shipping circles.

While Maritime New Zealand is still conducting investigations and has today allowed Aratere to resume service, stressing all possible measures are being taken to assure a safe resumption, it said it could confirm the grounding did not occur because someone had “left the bridge to make a coffee”.

Suggestions of bridge crew incompetence were first made in a 9 July social media post by the NZ First party of leader and current acting prime minister Winston Peters, who denied having input but said he was “certainly going to find out more”.

Mr Peters’ interest appears to have prompted the leaking of internal KiwiRail documents, including a 5 July safety bulletin that indicated crew may have been unfamiliar with the procedure needed to disengage the autopilot, following installation of a new electric steering system earlier this year.

After Aratere departed Picton for Wellington at around 2145 on 21 June the autopilot was switched on but an ‘execute button’ was pressed prematurely, causing the vessel to change course one nautical mile ahead of the planned waypoint. By the time the crew realised the predicament and was able to over-ride to restore manual steering “running aground was inevitable”.

In a statement Interisland Line EGM Duncan Roy said “Aratere’s autopilot system is not new and has been operating since 2007. It is important that we understand all of the factors involved in the incident, including the underlying causes. A fair and thorough investigation process is crucial for all parties and is being followed.”

Aratere was refloated after almost 24 hours aground under a cliff-face at Titoki Bay and later moved to a lay-by wharf at Shakespeare Bay for investigations and repairs.

Although none of the 47 persons on board was injured, there was no pollution and no penetration of the hull, DCN understands there was internal, structural damage to the forepeak and the section of the hull that was aground.

The incident left Interisland Line with only one of its three ferries operational as another was undergoing planned in-water maintenance.

The revelations of the unconfirmed circumstances of the grounding have unleashed a media and political storm in NZ, where the government-owned KiwiRail/ Interisland Line is constantly under intense public scrutiny. By contrast, the recent withdrawal of rival BlueBridge’s Connemara due to “critical safety issues” didn’t rate a mention; the ship resumed service by Monday night.