VIDEO: Troubled tow

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This video recently resurfaced on YouTube with no explanation, and although we learned that the accident was from 2009, it hasn’t lost its drama with age.

On July 19, the 42-foot tug North Arm Venture was towing the 170-foot, 786-ton barge North Arm Express — loaded with fuel and cargo — from Toba Inlet to Sechelt Inlet in British Columbia.

The captain decided to shorten the tow line to about 62 feet, including a 36-foot bridle, to enhance maneuverability for the transit through the narrows. About 15 minutes later the tug had capsized and all four aboard were in the water.

The crewmembers were rescued, two of them with minor injuries. The overturned tug and the barge were towed to Killam Bay.

The Transportation Safety Board of Canada investigated and in its report the agency found that about 4 minutes before the capsize, the captain increased power to proceed into an ebb current running at 1 to 2 knots, but the master noticed the current was diminishing. As the crew approached the narrows, the barge experienced a “shear to starboard,” according to the TSB, and the master commenced his alteration to port from a heading of 220 degrees to a heading of about 136 degrees.

The barge, however, did not follow through the turn and continued on its course. To regain control of the tow, the master sought to reposition his tug ahead of the barge by applying starboard helm, according to the report. The maneuver was unsuccessful, and the barge overtook the tug, which girded and capsized.

The TSB found four causes and contributing factors:

• The transit through Sechelt Rapids began prior to slack tide, and the barge came under the influence of the ebb tide, causing it to shear to starboard.

• The attempt to regain control of the barge was unsuccessful because of an insufficient reserve of power on the tug.

• The North Arm Venture capsized when the shortened towline pivoted athwartships; its force, then acting transversely, rapidly overcame the tug’s righting ability.

• The absence of procedures or guidelines on girding left the master without important information to aid in his decision-making.