In the latest Safety Digest, by the UK MAIB, a general cargo vessel’s starboard contacted a steep rocky shore, after a heavy rain squall caused significant clutter on the master’s radar display.
The incident
A small general cargo vessel was on passage overnight. Its primary means of navigation was paper charts and there was no electronic plotter on board. To avoid forecasted strong winds and remain in sheltered waters, the master decided to switch to an alternative route that passed between an island and the mainland, rather than round the outside.
The alternative route was familiar to the crew, with tracks from several previous passages already drawn on the chart. It involved passing between the island and a rocky outcrop, and the master decided to be on the bridge for this narrow section and assist the OOW by plotting radar parallel indexes. The vessel was making about 8 knots (kts) through the water and about 12kts over the ground with a strong tidal stream pushing it along.
About half a mile before the narrows, a fix had been plotted that showed the vessel to starboard of the planned track; this concurred with the master’s assessment by radar parallel index. A course of 260º was then set on the autohelm, intending to regain the planned 283º track.
About a quarter of a mile before the narrows, a heavy rain squall enveloped the vessel, reducing visibility and causing significant clutter on the master’s radar display. The bridge team lost visual and radar references and did not recognise that the vessel was not regaining track. Soon afterwards, the vessel’s starboard quarter made contact with the outcrop’s steep rocky shore, but the vessel did not stop.
Lessons learned
#1 Plan: Although the route was familiar to the crew, the decision to use it was taken late and this meant that a full appraisal of the alternative passage had not been completed. The effects of the tidal stream and courses to steer had not been precalculated; neither was consideration given to planning a ‘no-go’ point on the approach to the narrows. As the situation deteriorated, the bridge team did not have a plan to deal with the reduced visibility. Irrespective of familiarity with a route, a full appraisal of the passage is necessary to identify all potential hazards and make plans to avoid them.
#2 Monitor: The vessel was not fitted with electronic charting so was reliant on paper charts, visual bearings, global positioning service (GPS) fixes and radar for coastal navigation. These navigation methods require accurate, careful manual plotting, constant monitoring of parallel indexes, fixes and early action to regain track. Given the vessel was already off track to starboard when the fix was plotted, it was important to quickly identify the effects of wind and current and take bold action to regain, then maintain, track. This accident demonstrated that, although the vessel’s heading was altered intending to regain track, the action taken was insufficient and the bridge team ran out of time to accurately assess the situation and take further action to stay safe.
#3 Communicate: The coastguard was not informed of the incident and the company was only notified the following day after the vessel was alongside. Although the master was confident the vessel and crew were not in danger, it would have been prudent to inform search and rescue authorities and the company. The coastguard can monitor your progress, warn of dangers ahead and be ready to react to a deteriorating situation. Likewise, keeping the vessel’s management informed allows them to take early action to help safeguard the crew and prepare for damage assessments.
