TSB: Bridge team's failure to communicate led to tanker grounding

M12h0012 Photo 01

The following is the text of a news release from the Transportation Safety Board of Canada:

(DARTMOUTH, Nova Scotia) (Feb. 4) — The Transportation Safety Board of Canada (TSB) today released its final investigation report (M12H0012) into the grounding of the tanker Nanny in the Chesterfield Narrows, Nunavut.

On 25 October 2012, the Nanny departed Baker Lake, Nunavut for Lewisporte, Newfoundland and Labrador, then anchored north of Chesterfield Narrows to await high tide before continuing the passage. In this occurrence, the Nanny was initially required to proceed off the charted course in order to pass another tanker. Once clear of the other tanker, instead of returning to the planned route, the Nanny continued on a roughly parallel course that was off the charted route by distances of up to 0.12 nautical miles (nm). This deviation continued even as the vessel turned into Chesterfield Narrows, an area marked by unlit range beacons, that allows for little margin of error; the vessel ran then aground on a shoal. Two days later, the vessel came off the shoal due to strong winds and proceeded towards St. John's, Newfoundland and Labrador for repairs. No injuries or pollution were reported.

The investigation found that the Nanny ran aground because it deviated from the charted route when passing another tanker after departing the anchorage and did not return to it. The route deviation was not discussed by the bridge team, nor did they share navigational information throughout the voyage. Due to insufficient monitoring of the vessel's navigation and ineffective bridge resource management, the bridge team was unaware of the extent to which the vessel was off the charted course as it entered the narrows.

Since the accident, the vessel operator initiated a confined waters policy. This policy includes improved procedures to mitigate the risks of entering and sailing through confined waterways. The operator enhanced and accelerated its personnel training plan for bridge resource management and vessel handling. The operator has also implemented voyage data recorder training to ensure that available voyage data will be preserved after any incident.

Click here to read the complete report.

By Professional Mariner Staff