Initial report
Two crew members were performing a tender run ashore at night to collect a third crew member who was returning from shore leave. The helm was using the chart plotter to follow the transit routes that had been made earlier that day. The route was not a straight line because it had to take account of two rocks which protruded about 50cm above the waterline.
On the trip back to the parent vessel, the tender crew struck up a lively conversation with the crew member they had just collected, who was returning from an extended leave. This distracted them from monitoring the chart plotter and they hit the rocks at around 15-18kts.
The helm and deckhand were both thrown out of the tender by the force of the impact but were otherwise uninjured. Both were wearing life jackets and because the helm was correctly wearing the ‘kill cord’, the engine shut off. The collected crew member was thrown against the wind break and sustained bruised ribs.
Both crew members managed to climb back into the tender and radioed the yacht to let them know what had happened. The tender still worked so it was carefully navigated back to the yacht. When the tender was lifted out of the water the crew discovered large holes and gouges out of the hull.
CHIRP comment
Although the rocks were visible in daylight they were not lit or marked at night, and their silhouette might have been masked by background lights. Following the previous routes on the chart plotter would have been a sound choice but because of the lack of visual clues, and the conversation with the returning crew member, the helm became distracted from monitoring the chart plotter.
As their attention wandered, they likely forgot about the rocks and instinctively headed directly back to the yacht. At night the second crew member would not have had any visual cues that the tender was off course, so they were unable to remind the helm to regain the planned track. And unless the tender was being actively tracked by the crew on the yacht, they also would not have been able to raise the alarm.
Human factors and other issues identified in this report
Distraction – There is a natural tension between needing to concentrate on navigational safety and keeping your eyes and head ‘out of the boat’, while simultaneously being friendly and attentive to passengers and guests who might not understand the consequences of distracting the helm from their primary task.
Competence – Night navigation requires different skills to navigating by day. Regular training is required to keep these skills current.
Safety culture – A good safety culture will empower the helm to fend off distractions as they arise and also through a short safety brief at the start of every trip.
Report Ends………………….