According to UK MAIB, the skipper of a large scallop dredger became confused by the multitude of shore lights and struggled to ascertain his position in the channel.
large scallop dredger departed its home port shortly after dawn; it was a fine and sunny day with a gentle breeze. As the vessel was underway without its full crew or sufficient supplies to sustain the planned week of fishing, the skipper intended to pick up an additional crew member, some fishing gear and supplies from a harbour further down the coast that he had not visited before.
The scallop dredger arrived at the harbour later that day to collect the crew and supplies. As darkness started to set in, the skipper decided to proceed into the buoyed channel and navigated into it by eye, without a plan.
He was not referring to his navigational aids or charts and was also unaware of the effects of wind and tidal stream, both of which were pushing the vessel to port and out of the channel.
The skipper became confused by the multitude of shore lights and struggled to ascertain his position in the channel. The leading lights had not been identified and the vessel drifted out of the channel, running aground in mud and sand.
Under its own power, and with the aid of the local lifeboat, the scallop dredger was hauled off the bank undamaged.
- Plan: Avoid ad hoc pilotage; every arrival and departure must be appropriately appraised and planned. Such preparation should include: a chart assessment, identifcation of danger areas, safe navigable water and suitable navigational aids, evaluation of the environmental conditions, suitability of daylight versus darkness channel navigation, and the experience of those in the wheelhouse.
- Monitor: Leading lights are vital navigational aids to ensure the correct approach to a harbour. When entering at night, early detection of leading lights and their distinction from other lights, such as buoys and the shore, provide a reliable and easily identifable track for safe passage. Continuous monitoring will ensure any resultant drift is readily apparent and allow for suitable heading adjustments to be made.
- Teamwork: Entering a port for the frst time can be overwhelming for any seafarer, regardless of their experience. Skippers should be unafraid to ask another crew member to lend support in the wheelhouse. When things go wrong, a helping hand can provide a valuable safety net.
- Risk: Local environmental conditions must be considered before any port approach. The sea can often appear benign, particularly in protected waterways, but such conditions should not allow mariners to be lulled into a false sense of security. Anticipating the vessel’s expected drift is a quick and simple assessment that counteracts any potentially hazardous outcomes.