"Bayesian" accident: Owner Mike Lynch recovered dead, course of sinking unclear

On Monday night, the 56-metre-long aluminium sailboat was "Bayesian" sunk not far from Palermoafter a tornado raged off the coast. Of the 22 people on board the "Bayesian", 15 were found in a life raft immediately after the sinking.

The Italian fire brigade announced on "X" that more than 50 hours after recovering the first victim, they were able to recover four more bodies from the wreck on Wednesday afternoon. Another body was retrieved in the evening, which according to the Italian news agency ANSA is the body of "Bayesian" owner Mike Lynch. Diving for the last missing person, probably Lynch's 18-year-old daughter Hannah, continued on Thursday morning.

The fire brigade divers entered the yacht through openings provided for this purpose and not through windows. According to their reports, the mast is not broken. Detailed images from a coastguard remotely operated underwater vehicle (ROV) could provide information about the cause of the accident.

How did the "Bayesian" sink?

The rapid sinking of the "Bayesian" raises a number of unanswered questions. Sailing yachts from Perini Navi are regarded as safe and solid tall ships that can also compete in superyacht regattas in strong winds. There is much to suggest a chain of unfortunate circumstances.

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Open fuselage flaps

Even if the large aft and side boarding platforms had been open, the lazarette was separated from the engine compartment by a watertight bulkhead, which in turn was separated from the cabins by another watertight bulkhead. The flooding of a single section would hardly have led to a sinking, unless the door in the bulkhead to the engine room was open. Or additional water could have entered the interior via the 436 square metre deck. However, this would have meant that the 56-metre yacht, which displaces 540 tonnes, would have heeled very heavily without a single sail set.

Sudden listlessness

In connection with a possible sudden list, it is worth taking a closer look at the mast, which rises 73 metres into the sky and, even without the almost 3000 square metres of sails, offers a not inconsiderable area exposed to the wind. As the aluminium mast was inserted through the deck, it is likely to have been almost 70 metres long in the wind. Archive photos suggest an average mast depth of one metre, taking the taper into account. This would result in a "passive sail area" of around 70 square metres. A heel generated by the mast could have lifted the 11.52 metre wide hull slightly on the windward side so that additional parts of the underwater hull were available to the wind as an attack surface at hurricane force. In addition, a raised lift keel could have further reduced the tilting stability. With the keel fully extended, "Bayesian" had a draught of 9.38 metres, compared to 4.05 metres retracted.