A vessel ran aground near Golden Bay after an alcohol-affected and sleep deprived crew member stopped monitoring its course, an investigation has found.
The Transport Accident Investigation Commission this morning said there was a "strong possibility" an experienced ship mate on board the M.V. Anatoki had fallen asleep before grounding the vessel off Rangihaeata Head on May 6, 2010.
It said the mate had drunk "four to five" pints of beer in the hours before the vessel departed at midnight on May 6.
He did not properly monitor the ship's course after being placed on watch at 4am and failed to realise the vessel was in trouble until at least 10 minutes after it had grounded, it said.
"The Anatoki ran aground because the mate was not adequately monitoring the progress of the ship against the passage plan and the master's night orders, and in the period immediately before the grounding, could not have been monitoring the progress of the vessel at all."
The ship was refloated at 1pm on May 6, with the help of a workboat and a charter fishing vessel.
Though the mate was "adamant" he had not fallen asleep, the sequence of events leading to the grounding showed that was highly likely, TAIC said.
He had only had a maximum of three-and-a-half hours of sleep in 21 hours and his rest was likely to have been affected by alcohol consumption, it said.
It found he had not altered the ship's course from 4:08am until the time it went aground.
A marker on the ship's chart showing its position at 4:30am was inaccurate and may have been placed there after the grounding, it said.
"If he had not fallen asleep, he must have been doing something other than monitoring the progress of the vessel.
"The performance of the mate on watch was probably impaired by acute sleep loss, possibly exacerbated by the consumption of alcohol the evening before, which is known to affect the quality of sleep."
TAIC criticised the ship's master for his "tacit acceptance" of the ship mate's drinking.
It called for the owner of the Anatoki to manage standards of navigation and drug and alcohol policy more effectively.
"Whether alcohol consumption contributed to this accident or not, this is another case where abuse of alcohol in the maritime workplace has been identified as an issue."
"Responsible watchkeepers should take the opportunity to have adequate sleep to prevent their becoming fatigued. Under no circumstances should crew undertake safety critical tasks when impaired by alcohol. alcohol consumption can reduce the quality of sleep even hours after consumption stops."By Hayden Donnell Email Hayden