Federal safety investigators yesterday put most of the blame on the Navy for a bizarre accident last year in which a nuclear submarine waiting to play a role in a movie, "The Hunt for Red October," snagged the towline of a tugboat and sank it.
The National Transportation Safety Board said the June 4, 1989, accident off southern California occurred partly because the Navy's policy governing how submerged submarines should operate in crowded waters is unclear.
One tug crew member died in the accident, which occurred in the predawn darkness and fog between Los Angeles-Long Beach Harbor and Santa Catalina Island.
The tug, the Barcona, was towing two empty barges from Long Beach to Santa Catalina. The USS Houston, in the area to participate in the filming later in the day of scenes for the movie, was submerged at periscope depth. The sub extended its antenna to obtain a navigational fix and the antenna caught the Barcona's towline.
The towline did not break. Instead, the submarine pulled the barges and the tug by the snagged line. The tug moved backwards, water washed over its low stern, and within seconds it sank. Two other Barcona crewmen escaped on a life raft and were later rescued.
The Safety Board said Navy submarines use a variety of procedures to ensure that other vessels are at a safe distance when periscopes and antennas are raised above the water line. But the board said those procedures sometimes differ from recommended practices.
The Houston usually used short-wave sonar, known as under ice sonar, to detect potential obstacles on the surface, but the equipment was not working at the time of the accident, investigators said. Navy policy for using more powerful sonar, known as active sonar, was not clear, the board said, but it could have played a key role in averting the tragedy off California.
The board also said the tug industry should be required to install emergency release mechanisms for towlines that can be operated from pilothouses, to equip boats with alarm systems that can alert crew members to emergencies and to keep watertight doors on the main deck closed while operating in open water.