Marine Accident Investigation Branch Safety Digest 1/2005  Case 9

Zzzzzz - Bump - Where am I?

Narrative
In the early hours of a summer morning, a foreign general cargo vessel ran aground on the west coast of Scotland. The single-hold vessel was built in 1990 and was carrying 3300 tonnes of zinc concentrate. She subsequently sank, prompting fears of serious environmental damage in an area of outstanding natural beauty.

The vessel carried 7 crew, with the master and chief officer holding the 6 to 12 and the 12 to 6 watches respectively. In addition to watchkeeping, the chief officer was responsible for overseeing cargo operations in port.

The able seaman assigned to the watch was absent from the bridge for at least an hour before the vessel grounded. No watch alarm was fitted on the bridge.

The chief officer fell asleep while alone on the bridge, missing an intended change of course. He was awoken, standing at the engine controls, by the impact of the vessel grounding. The sea was calm, there was no swell and the visibility was good. It was daylight, although the sun was yet to rise. The vessel was stationary aground.

The circumstances of this accident are, unfortunately, not uncommon. In fact, watchkeeper incapacitation or absence leads to about 6 groundings a year in UK waters alone, and over 58% of all the collisions and groundings investigated by the MAIB over the last 5 years, can be attributed to single-handed bridge watchkeeping.

The Lessons
1. Six-on six-off watches are tiring in any event, and this problem was made worse by the regular port visits, during which time the chief officer was still required to work, regardless of how this disrupted his watch pattern. He fell asleep as a result of very high levels of fatigue caused by the cumulative effect of this irregular working pattern. It is also likely that his decision to allow the AB to leave the bridge was as a result of poor perception of the risks, also caused by fatigue.

If you are tired, not only are you more likely to fall asleep, but your judgment will also be affected, often without you realising it. Working within the hours of work regulations does not necessarily protect you from fatigue. If you are in any doubt as to your fitness for duty, tell the master. The company will not thank you for saving a few hours if its vessel is lost as a result!

2. The only real protection from fatigue isadequate manning for the work being done. The manning level on this vessel was within that stated on the vessel’s Safe Manning Certificate. However, this is a minimum requirement, and does not take account of the vessel’s trading pattern.

Had the able seaman been on the bridge, or had the bridge been equipped with a working and switched on watchkeeper alarm, it is likely that the mate would not have been asleep long enough for the vessel to have run aground. He would, however, have been just as tired, and likely to make serious errors of judgment as a result.

Had there been another mate on board, all the navigating officers would have been able to gain sufficient rest. Fatigue would not then have been an issue.