DECISION FRAMEWORK: A SCENARIOFOR DECIDING WHETHERTO JETTISON CARGO

Captain Kenneth Fullwood

I think it true to say that no one with any knowledge of ships and Archimedes' principle would question that one way, and often the only way, to float a stranded ship is to make her lighter by removing some of the cargo. The problem arises when the ship happens to be a loaded oil tanker and there is no time to obtain another vessel to receive the cargo. To focus on the question of whether to deliberately discharge a relatively small quantity of oil into the environment, and by so doing to avoid the eventual release of a much larger quantity, I developed the following horror story. I rather like sea stories, but not this one.

The possibility of the particular set of circumstances described in our story coming together like this is very remote. I should point out, however, that 80 percent of accidents can be traced to human error and are seldom due to a single factor. It is almost always the cumulative effect of a series of unique events which finally trigger a disaster.

An 80,000-ton tanker is enroute from Mexico to a refinery on the Delaware River with a cargo of 78,500 tons of Isthmus crude oil. The ship is at a draft of 40 feet and making a speed of 15 knots. The captain had been plotting the track of a hurricane which was centered about 430 miles away, just ahead of the starboard beam and heading west at 12 knots. The storm was guided by a very large and stable ridge of high pressure stretching from Tennessee, through Ohio, northeast to Quebec, Nova Scotia, and Newfoundland. It was expected to cross the coast near Wilmington, North Carolina.

The captain decided to continue his voyage to the Delaware, expecting to pass 350 miles ahead of the hurricane. He made the first human error in our story by deciding to increase his distance from the hurricane by setting his course closer to Cape Hatteras than he normally would have done. This was unnecessary and based on emotion, but nevertheless he did it. Shortly after course was changed to pass closer to Cape Hatteras, the gyro compass developed a mechanical problem, which resulted in the ship steering to the west of her set course. This was followed by more human errors when the officer of the watch failed to observe that the ship was straying from her set track, and again when he failed to notice that Diamond Shoal light and the R2 buoy were on the wrong side of the ship. The ship ran onto the shoal at 15 knots and came to rest with 80 percent of her length resting on the sand.

The shoal is soft sand, and although the bottom plating may have been set up, there were no leaks. The power plant was not damaged, and the captain tried unsuccessfully to back the ship off using her engine.

The wind by this time was in the northeast at 20 knots, and the center of the hurricane was still some 300 miles away to the east. Figures 1, 2, and 3 show the



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