Marine Accident Report: U.S. Tug SENTINEL, Loss of Tow and Resultant Grounding of Barges KONA and AGATTU, Gulf of the Farallones, Pacific Ocean, December 31, 1979

摘要

About 0400 P.s.t., on December 31, 1979, the tugboat SENTINEL, outbound from San Francisco Bay while towing general cargo barges, the KONA and the AGATTU on separate cables, experienced a failure of a towing cable which cast the KONA adrift. About 0445, while the SENTINEL was maneuvering to prevent the AGATTU from overriding the KONA, the AGATTU's towing cable became caught in the SENTINEL's starboard propeller and was cut, casting the AGUTTU adrift. Both barges drifted toward the lee shore and grounded. The SENTINEL returned to port safely. As a result of this accident, both barges were declared constructive total losses. Cargo was damaged and lost from both barges. The total economic loss resultant from this accident was estimated at about $8.2 million. The National Transportation Safety Board determines the probable cause of the loss of the KONA was a buildup of excessive tensile stress in the barge's towline after it encountered an unusually large wave and the inability of the SENTINEL's towing machine to relieve this stress, possibly due to a manual brake being adjusted too tightly.