Based on U.S. Coast Guard reports.
A vessel casualty can occur quickly and at any time. The circumstances leading to a casualty are not always easy to identify, nor can they always be predicted. The task is knowing how to react in a given situation.
Preparing for common emergencies like a fire, uncontrolled flooding and sinking, or a man-overboard situation certainly is critical. By completing safety orientations and conducting emergency drills as required, your crew will be more aware and better prepared to respond in an emergency and survive. However, it's also wise to familiarize yourself and your crew with other types of contingencies, such as a serious injury or medical emergency, loss of power, loss of steering, gear becoming snagged, or stability problems. Let's examine an operation and stability problem that turned into a casualty on a Gulf Coast shrimp boat.
A 39-foot steel-hulled shrimp trawler built in the early 1980s was operating out of Cameron, La., with a crew of four — the skipper, two deckhands and a cook. The vessel was fitted with outriggers for trawling and a lifting boom. On this trip in January, the wind and sea were calm, the visibility was good, and the temperature was in the mid-60s. The vessel was operating in 20 feet of water about two miles offshore. The only adverse condition was a strong current running from the West.
While trawling in a southerly direction for their next set, some part of the gear got caught up on the seafloor. The vessel heeled over to starboard, and water poured in through the engine room, ice hold, and lazarette hatches, which were all open at the time. The uncontrolled downflooding caused the vessel to capsize and sink within at matter of minutes.
The skipper and the deckhands were forced into the water without PFDs. However, they were able to climb aboard their life raft a few minutes after it floated free and inflated automatically. About 45 minutes later, a nearby fishing boat picked them up. One member of the crew, the cook, was trapped inside the trawler and presumed drowned when the vessel capsized and sank. Divers recovered his body a week later.
In this case, the cause of the casualty is easy to identify (though at the time, it was not necessarily predictable). The heeling and downflooding immediately affected the vessel's stability. The lack of watertight integrity and subdivisions on the trawler contributed to the capsizing.
Vessel stability is a challenging issue for boats of any size. In this incident, when the trawler's net got caught on the seafloor, two simultaneous forces affected the vessel's stability. The gear entangled on the seafloor added weight and drag to the outrigger. This caused the vessel's center of gravity to move upward, reducing the trawler's inherent stability.
As stability is reduced, a vessel is less able to recover from lists or rolls. The snagged gear applied more pressure to the outrigger, and it began to pull the vessel over as the trawler's forward momentum had to be redirected. Then, with the downward pull on the outrigger and the vessel not able to make any way, the strong current had an added effect. The current was on the vessel's starboard beam and pushed the vessel such that it heeled over even more, took water over the deck, and flooded into the open hatches. The result was that the boat capsized and sank very quickly.
There was virtually no time to release the trawl's cable from the drum so the vessel would not be dragged under from the holding force of the gear caught on the bottom. There was no watertight integrity on the vessel, because the hatches were left open, there were no watertight hatches or doors, and no watertight subdivisions. Had any of these conditions been different, there may have been time for the crew to react to the emergency situation, save the vessel, and most likely save the life of their crewman.
There is no way to ensure safety on any vessel. Drilling and practicing emergency responses, as listed and required in the regulations, is the only way to ensure preparation. Being aware of your surroundings and operations at all times — the captain at the operating station, or a crew member at the equipment controls — is another critical element of survival at sea.
Crews should also think about and plan for responding to other types of hazardous or emergency situations. Is there a quick way to release the cable and net from the outrigger and winches in case gear gets hung up on the bottom? How quickly can you take the vessel out of gear or back down? How do you prevent downflooding when water washes over the deck, particularly if the vessel is heeled over? Are doors and hatches kept closed when not in use? How will the sea state and currents affect your vessel if there is a stability problem?
An emergency can arise at any time. Have you drilled or practiced for the various emergency contingencies? Are you prepared to respond to the accident waiting to happen? Be aware, be safe, be ready! When seconds count, training can make the difference.