In a highly critical official report into Mirabella V’s grounding in the south of France last September, the Isle of Man Marine Administration has brought into question rules used to calculate how big her anchors should be.

The report also criticised skipper Johnno Johnston for deciding too late to move from a lee shore and for not taking measures ‘to improve anchoring arrangements in the increased weather conditions’. Neither did the report’s authors believe the vessel was in a suitable state of readiness ‘given the high level of risk created by the yacht’s position and the prevailing weather conditions’.

It also highlighted shortcomings in communications procedures between the bridge and the engineroom, where high noise levels meant the chief engineer couldn’t initially hear the skipper’s instruction to start the engines when the anchor was dragging.

Although Mirabella’s anchors were well in excess of the weight recommendations set by Det Norske Veritas, the classification society used by her designers, the rules failed to take into account the windage of the yacht’s rig – only the hull and superstructure windage was accounted for. The report concludes: “the frontal area of the rig…should have been factored into the calculations for the size of the anchoring equipment fitted.”

If this had been done, the Lloyd’s Register calculations (which exist for certain sailing ships) would have decreed that her main and secondary anchors be 80 per cent heavier at 1080kg and 756kg. As it was her heaviest anchor was just 600kg.

Remarkably, the investigators calculated that the frontal area of the rig, including the mast itself and the three furling headsails, amounted to approximately 114 square metres compared to 71.7 square metres for the hull only and that did not include standing rigging, spreaders or equipment such as radars.

Lloyd’s Register Rules require 25 per cent larger anchors to be fitted to three (or more) masted square-rigged ships but because Mirabella V only has one mast the high rig windage factor was not used in the calculations.

From a seamanship point of view, the report concluded that it might have been more appropriate to have paid out more chain when the weather deteriorated, especially as they were on a lee shore. It also pointed out that ‘The Master did not take into account all the information available to him preceding the incident, including the weather forecasts (the NAVTEX weather receiver was out of paper), so that the decision to weigh anchor and move to Villefranche was taken too late’.

Owner Joe Vittoria was unable to comment on the findings as he was aboard Mirabella in the Virgin Islands following successful repairs to the yacht’s damaged keel but his son Joe Vittoria Jnr said: “The anchor situation may be one of the areas where MV (Mirabella V) has shown that classification societies and their rules are not going to be appropriate every time for every vessel.

“If Johnno didn’t take all prudent measures last summer, he sure is now! That event has left a scar on him that will never go away and he will be a better captain for it.”