Mike Lynch superyacht sinking possibly stemmed from design-related vulnerability

A report into the sinking of a superyacht that killed a British tech tycoon outlined on Thursday how the vessel's design had left it "vulnerable" as it was battered by hurricane-force winds.

The luxury 56-metre (185-foot) Bayesian was struck by a pre-dawn storm on August 19, 2024 as it was anchored off Sicily and sank rapidly, killing Mike Lynch and six others, including his 18-year-old daughter, and the boat's chef.

Lynch, the 59-year-old founder of software firm Autonomy, had invited friends and family onto the yacht to celebrate his recent acquittal in a U.S. fraud case.

The interim report published by a British investigative body Thursday said the vessel might have been "vulnerable" to the winds, especially under a set of conditions which included running on its motor mode and having its sails lowered.

The Marine Accident Investigation Branch (MAIB), a UK government agency that looks into accidents involving British ships around the world, said wind speeds of around 73 miles (117 kilometres) per hour were enough to knock it over under these conditions, and possibly even in lighter winds.

But it said these "vulnerabilities" were "unknown to either the owner or the crew of Bayesian" as they were not included in an onboard manual.

On the night of the sinking, sudden "hurricane force winds" well over 73 mph knocked the yacht over in under 15 seconds as "people, furniture and loose items fell across the deck", the report said.

The Bayesian had an exceptionally tall mast at 72 metres (236 feet), and the investigators said its profile "produced a degree of effective lift" that increased the amount the boat leaned over in the wind.

The MAIB was unable to examine the vessel, as the wreck still lies at a depth of 50 metres, but said it reviewed its design and operation, as well as the weather conditions.

Efforts to raise the yacht from the seabed were suspended after the death of a diver working to remove the mast last week.

That salvage operation is due to resume on Thursday, according to TMC Marine, the company in charge of the mission.

In England, coroners inquests are looking into the deaths of four British victims, while in Italy prosecutors have opened investigations into the captain and three others on suspicion of manslaughter and the crime of negligent shipwreck.

The MAIB said the details in its report could change if Italian authorities released further information.