Consequently, every professional mariner makes mistakes. Most of our mistakes are caught and corrected before they become a crisis. Before we look at the regulatory and common-sense tools that help us overcome fatigue and thus avoid making mistakes, let’s look briefly at two cases where fatigue directly contributed to catastrophe.
The tankship World Prodigy with a cargo of 195,000 barrels of diesel fuel approached the entrance to Narragansett Bay on the afternoon of June 23, 1989. World Prodigy was no Third World rust bucket. Not quite three years old, she had a satellite navigation system, Decca, loran, radio direction-finder, two radars, two VHF-FM radios, multiple gyrocompass repeaters and rudder-angle indicators, and telephones for intraship communications.
Nonetheless, ships are run by people. World Prodigy’s watch officer called his captain to the wheelhouse at 0500 on June 22 because of the New England summer fog and fishing vessels. Having had just about six hours of sleep, the captain began conning the ship so the mate could concentrate on navigation and monitoring the radars.
The captain stayed on the ship’s bridge all day, through the night, and into the next morning taking only short breaks to eat and getting occasional, brief naps on a couch on the bridge. But those naps were short, and he was up far more than he was resting.
By 1600 on the afternoon of June 23, the visibility had increased to 10 miles. The captain continued to conn World Prodigy because the ship was about to embark a pilot. He reduced speed, shifted the steering from automatic to manual and sent the lookout below to assist the boatswain in rigging the pilot ladder.
Then World Prodigy received a telex directing her to offload at two terminals instead of one and asking the master to calculate, “as soon as possible,” the ship’s estimated draft after the first offload. World Prodigy’s captain sent the on-watch chief mate below to use the ship’s stability computer to make the computations. This left the captain alone in the wheelhouse except for the helmsman.
At 1628 the master ordered “dead slow ahead,” but World Prodigy was still making over 4 knots as the captain fixed his position and spoke with the pilot boat. After 10 minutes, he grew impatient with the chief mate’s tardiness in completing the draft calculations. So the captain went to the back of the wheelhouse and began doing his own computations using a pocket calculator. This left the helmsman as the only person in the forward part of the bridge.
Two minutes later the pilot boat saw World Prodigy and told the captain to make an immediate 90Â° course change to port. Before the master could respond, World Prodigy struck a rocky ledge, damaging 16 cargo tanks and spilling 300,000 gallons of diesel oil into Narragansett Bay. The captain had, by then, been up and on watch for almost 36 hours.
Not surprisingly, the National Transportation Safety Board found that the captain’s “acute fatigue” was the probable cause of the ship’s grounding. Mishaps involving less obvious cases of fatigue also exist.
In June of 1995 the passenger vessel Star Princess was making a routine voyage along the Alaska Inside Passage. State law mandated that ships transiting these passages have two licensed pilots onboard so that one of the pilots could continuously direct the vessel’s movements while the other rested.
So it was on Star Princess. The two pilots shared watch-standing duties on a six-on, six-off basis until the ship arrived at Skagway early on June 22. When Star Princess departed for Juneau late the same day, the pilots decided to split the remaining 10.5 hours of watch in half.
The second pilot came on watch at about 0040 on the morning of June 23. At 0125 he sighted Fair Princess on a reciprocal course about 6 miles to the south. Neither Star Princess’ nor Fair Princess’ pilot was concerned; both believed their ships could pass port-to-port between the navigational hazards of Poundstone Rock to the west and Sentinel Island to the east without colliding. At 0142, with Fair Princess on her port bow at a safe distance, Star Princess’ starboard side grounded on Poundstone Rock. The passengers were all debarked from the damaged ship. Repairs and loss of revenue during repairs amounted to more than $27 million.
Star Princess’ pilot had been on watch for less than an hour. In the 24 hours before that he had a total of about five and a half hours on watch. In the 12 hours before that, he had two hours of watch. In other words, he had more than 27 hours of rest in the 36 hours before the grounding, including 18 continuous hours without duty just before his final watch. Nonetheless, he was suffering from fatigue. How can this be?
This man had a disorder known as sleep apnea, a condition in which a sleeping person stops breathing, causing him or her to wake up suddenly. This waking may occur hundreds of times each night, but it is so short in duration that the individual often does not realize he or she woke up. Nonetheless, anyone who wakes up this much each night is going to be tired. The pilot’s sleep apnea was not diagnosed until after the grounding. He was tired and no one, not even he, suspected it.
Here then is the first step to counteract fatigue: Guard against undiagnosed sleep disorders. Routine medical examinations may turn up such problems. (Or they may not, as was the case for the pilot of Star Princess.) It is more likely, however, that those who know an individual best (spouse, parents, children, shipmates) will see the symptoms of chronic fatigue that mean a thorough evaluation is in order.
However, individuals with genuine sleep disorders are rare: Less than 10 percent of everyone in the country suffers from sleep apnea. For the remaining 90 percent of the population, the most obvious solution for fatigue is to get adequate rest each day. Most humans need eight hours of sleep, preferably eight continuous hours, in a 24-hour period. That is often difficult for shipboard watch standers. Even a four-on, eight-off watch schedule will barely provide eight hours of continuous rest, and many smaller workboats have a six-and-six watch schedule.
Lately some companies have been experimenting with a nontraditional watch-standing schedule that guarantees each watch stander a continuous off-watch period of at least 10 hours to improve the probability of eight continuous hours of sleep.
Even if we are getting the required amounts of sleep, there is one more thing that will cause us to suffer fatigue: work. That sounds obvious, but at the end of watch, whether it is midnight or eight in the morning, the watch stander is tired. And, being tired, he or she will begin to suffer from fatigue no matter how much rest he or she got before watch.
The Code of Federal Regulations now includes the STCW (International Convention on Standards of Training, Certification and Watchkeeping for Seafarers) rest standards, which mandate a minimum of 10 hours off watch in any 24-hour period, including at least six continuous hours of rest. Other CFR work-rest rules pre-date STCW and are still in effect. Furthermore, the Oil Pollution Act of 1990 (OPA ’90) imposes still other rest requirements for tanker crews.
Despite these regulations, there are court cases that indicate a reluctance by the legal system to enforce these rest rules in favor of the mariner. Furthermore, there are gray areas in the regulations that seem to allow, or even encourage, additional work hours. Thus, since the rules alone will not solve the problem, professional mariners must seek other solutions.
Formal studies about fatigue tend to prove the very things we know from our own experience. When we’re tired, we overlook things, our perceptions diminish, we become impatient with ourselves and others, we find it difficult to concentrate, and we tend to concentrate on one thing to the exclusion of all others.
Knowing the causes and consequences of fatigue, what are the symptoms we can watch for? The first is impaired judgment. Unfortunately, that means the fatigued individual may not realize that he or she is tired. Thus we must learn to watch for signs of fatigue not just in ourselves, but in our shipmates.
Secondly, someone who is tired becomes less willing to talk about anything, let alone his or her fatigue. Once again, trying to tell someone else that he or she is tired means an uphill battle against the effects of fatigue.
Third, an individual suffering from fatigue is more likely to make mistakes or simply not do some things that should be done; i.e., take shortcuts. Simultaneously, someone with multiple jobs to do may concentrate on just one task while ignoring others, thus getting even further behind, leading to more shortcuts and a downward spiral in performance.
How do we deal with all this?
We can overcome the third consequence of fatigue, shortcuts and errors, by using standardized procedures and checklists. When we stop following our normal procedures, we have to ask ourselves if those changes are being caused by fatigue.
World Prodigy’s captain effectively left his helmsman alone in the wheelhouse as the ship approached the pilot station, counter to his usual practice. Even though he had asked for another mate to come to the bridge, when that mate did not show up, the captain never got anyone else.
The second consequence of fatigue, decreased communication, is the most difficult to overcome. If someone ignores us, we tend to ignore him or her in return. Star Princess’ pilot not only failed to make radio contact with Fair Princess, he had not even discussed his ship’s navigation with his own crew for almost 30 minutes prior to the grounding. Poor communication was also a factor in the World Prodigy grounding. Although the captain talked with the pilot boat about his arrival, he misunderstood the location of the boarding area. Rather than ask for clarification, the captain remained silent.
The first consequence of fatigue — loss of judgment — is perhaps the most dangerous. Since World Prodigy’s captain understood his responsibilities for the safe navigation of his ship, he had been on the bridge for almost a day and a half because of the fog and heavy traffic. Since he also understood his chief mate’s duties, he told the chief mate to do the draft calculations. He even had the good sense to call for another officer to join him on the bridge as the ship approached the pilot station.
But then his judgment faltered. When the extra mate did not show up, he made no attempt to locate anyone else to assist him. When the draft computations took more than 10 minutes, he started his own calculations. Alone on the bridge except for the helmsman, he began to assume all duties (lookout, navigator, ship handler, radar observer, stability calculator, radio operator, supervisor).
Deteriorating judgment, concentration on secondary matters and failure to communicate, all hallmarks of fatigue, were the characteristics shown by World Prodigy’s captain in the minutes before his ship grounded.
We must learn to understand the causes of fatigue, recognize its symptoms, and do something about it if we are to avoid World Prodigy’s fate. â€¢
Mike Adams is a master mariner and captain of a large oil spill response vessel. He is a Coast Guard-certified STCW instructor for bridge resource management and basic safety.