News release

Ineffective communication and a lack of teamwork contribute to November 2011 shipping accident

Gatineau, Quebec, 9 April 2013 — The Transportation Safety Board of Canada (TSB) released its investigation report (M11N0047) into the November 2011 striking incident involving the supply vessel Maersk Detector and the mobile offshore drilling unit GSF Grand Banks in the White Rose oil field off the Grand Banks of Newfoundland. Poor communication between the vessel's bridge officers, as well as between the vessel and the rig, allowed the cargo operation to continue with key personnel unaware that the risk of striking was high.

On the afternoon of , the Maersk Detector was loading cargo from the drilling unit. Weather was deteriorating at the time, with increasing swells arriving from the south. During this operation, the vessel maintained its position relative to the drilling unit by means of an electronic control system called dynamic positioning. At 15:30, Newfoundland Standard Time, the Maersk Detector's port stern struck a column of the GSF Grand Banks, holing both the vessel and the rig. There were no injuries and no pollution resulting from the striking.

The investigation found that the relevant weather information was not provided proactively to the bridge officers, so they were unaware that the weather limits for the operation had been reached. Furthermore, the bridge officers did not work as a team, nor did they thoroughly use electronic data available to them to maintain separation distance. As well, the Master prioritized his visual assessment of distance and position over the dynamic positioning alarms and warnings, which were indicating that the vessel was not maintaining its position well. The Board also found that, without formal bridge resource management training and continued proficiency, there is an increased risk to the vessel, its complement and the environment.

The ship operator, Maersk Supply Services Canada Ltd., and Husky Oil Ltd., the oil field operator, have made important changes to their operations to mitigate the risk of a similar accident happening again. Transport Canada has also proposed amendments to the Marine Personnel Regulations regarding bridge resource management training.


The TSB is an independent agency that investigates marine, pipeline, railway and aviation transportation occurrences. Its sole aim is the advancement of transportation safety. It is not the function of the Board to assign fault or determine civil or criminal liability.

For more information, contact:
Transportation Safety Board of Canada
Media Relations
Telephone: 819-994-8053
Email: media@tsb.gc.ca