On the 13 September 2004, Mirabella V anchored just outside the port of Saint Jean on the French Riviera where the water depth was 17-18m. The yacht was equipped with two anchors, one 400kg and one 600kg. The 600kg anchor was deployed and 65m of chain was paid out. At the time there were no guests on board and the wind was light and variable and there was negligible tidal current.
“Three days later on the 16 September 2004, from 0800Hrs onwards, the wind and sea state steadily increased until at approximately 1300Hrs the yacht’s anchor suddenly dragged and within a matter of minutes the yacht drifted onto the rocks at Pte Rompa de Talon,” the report reveals. “The wind was 20-22 Knots (onshore) and sea state was Beaufort 4. The crew attempted to start the engines but did not manage to do so before the yacht grounded. The initial grounding broke the securing mechanism for the lifting keel, which then dropped to the seabed and secured the yacht in position. The yacht was subsequently re-floated in more favourable weather conditions, when the keel lifting mechanism was temporarily repaired and the keel lifted off the seabed.”
“There were no injuries, nor loss of life and pollution of the environment was insignificant,” the report confirms. “The yacht sustained structural damage to the keel, keel box, keel lifting mechanism, starboard rudder and transom flap.”
The report goes on to draw a number of conclusions so that appropriate recommendations can be made in order to avoid similar situations arising in the future. “The crew paid out a reasonable amount of chain, for a normal yacht, in the weather conditions at the time of anchoring,” the report assesses. “This was in accordance with their training ... Although the type of anchor fitted to the Mirabella V is different to that fitted on most merchant vessels, the size and purpose of the chain is very similar. The merchant philosophy, with regard to a greater amount of chain to be paid out, may have been more appropriate, especially when the weather deteriorated.”
Furthermore, the report reveals that the tendency of the yacht to swing at anchor, coupled with a short scope of cable deployed, caused a lateral load on the anchor shank. “The anchor was pulled out from its holding position by a large transverse pull on the anchor shank, possibly cyclical as the yacht swung about her anchor,” it states. “The selection of the anchoring position was not unsafe in the light and variable wind conditions prevailing when the yacht anchored. This anchorage would be the preferred anchorage over Villefranche, had the wind turned to the South West. The master did not take into account all the information available to him preceding the incident, including weather forecasts, so that the decision to weigh anchor and move to Villefranche was taken too late.”
At the time of the incident, the captain was in the bridge and fully aware of the conditions. “The master became immediately aware when the anchor began to drag by looking out the bridge windows and observing a sudden change in heading (the bow falling away to starboard),” the report continues. “Although the engines were swiftly started by the engineers, the time lag proved too long. The vessel was not in a suitable state of readiness, given the high level of risk created by the yacht’s position and the prevailing weather conditions.”
“The crew of this yacht should develop techniques for reducing the amount of swing at anchor. The owners should provide the necessary technical back up and equipment to enable them to do so,” the report recommends. “Owners should reconfigure the engine platform management system to provide a safe option for leaving the propulsion system in an immediate state of readiness at anchor. In an emergency, the propulsion system starting sequence should be easy to initiate, by the anchor watch keeper, from his watch keeping position, without the assistance of an engineer. The vessel’s procedures should specify the various states of engine readiness options available and the characteristics of each.”
The full investigation report can be read here.