A heavy-payload carrier ran aground in the St. Lawrence River last year because part of a linkage mechanism detached and became wedged in a position that prevented the movement of the rudder, an investigator said.
Sedna Desgagnés, a 456-foot-long cargo ship, ran aground near Ogdensburg, N.Y., on Oct. 14, 2012. The lift-on/lift-off vessel was on its way from Sorel, Quebec, to Chicago with a load of raw iron.
The 9,611-gt multipurpose tweendeck ship, able to carry heavy payloads, was built in 2009 in the Qingshan Shipyard in China.
Owned by Transport Desgagnés Inc. in Quebec City, the vessel departed Montreal and had just passed under the international bridge near Prescott, Ont., when it ran aground on the U.S. side at around 0800. The 12,744 mt deadweight ship was aground for five days before being freed.
The Transportation Safety Board (TSB) of Canada’s investigation determined that a mechanical steering problem caused the grounding, Investigator-in-Charge Luc Charbonneau said in an e-mail.
“The vessel experienced a loss of steering control when the articulated flap linkage arm, which was detached, became wedged in a position that prevented the movement of the rudder,” Charbonneau wrote. “This caused the vessel to veer to port and run aground. The investigation has not determined when the linkage arm became detached. However, the TSB is aware that the rudder flap linkage axle nut and axle were missing.”
In addition, Charbonneau noted that the investigation found that the articulated flap rudder had not been installed according to the manufacturer’s specifications.
“In this instance, the axle nut was found to be locked using a tab welded between the linkage arm and the nut, as opposed to the designed arrangement that called for a welded locking plate between the nut and the axle,” he wrote.
The TSB issued a Marine Safety Advisory Letter to inform the International Association of Classification Societies Ltd., Transport Canada, the owners and the shipyard of the findings in this occurrence.
Serge Le Guellec, president and general manager of Transport Desgagnés Inc., said the root cause of the accident is attributable to inadequate quality control at the shipyard where the vessel was constructed.
“As it turns out, the ‘as built’ configuration was different from the ‘as designed’ configuration,” he said. “The deficiency went unnoticed when the classification society completed its inspection of the type-approved steering gear system during the acceptance process prior to the owner accepting delivery of the new vessel.”
Transport Desgagnés took steps to repair the defective steering gear system, Le Guellec added.
“We have implemented a modification that modifies the existing movable arrangement into a fixed one in order to negate recurrence of the accident,” he said.
Inspections indicated that the problem was isolated to the Sedna Desgagnés steering gear system.