The diver that lost his life while working on the salvage of the lost superyacht Bayesian may have been killed by an explosion from a hydrogen torch, according to reports in Italian media.
The diver has been identified as 39-year-old Dutch national Rob Huijben, an employee of salvage company HEBO. He lost his life as the team was working to remove part of Bayesian’s boom or a part of its gigantic aluminum single-masted rig, at one time the tallest mast of its kind in the world. Local media report that he was killed by an explosion while using an underwater oxy-hydrogen cutting torch.
Dutch marine news outlet Schuttevaer reports that Huijben was working on removing Bayesian’s boom. The team initially attempted to unbolt it, according to the outlet, but when this failed they opted to burn through it. It is believed that an explosion – possibly from hydrogen bubbles – caused a piece of metal to break loose and hit Huijben.
According to commercial diving historian Francis Hermans, the risk of igniting unburned hydrogen gas from an oxy-hydrogen torch has been known since at least World War II, when U.S. Navy salvage divers found that there could be difficulties with highly explosive gas accumulation in enclosed compartments when working inside of wrecks. This was reportedly among the reasons that Navy operators turned to the oxy-electric arc torch, which requires only oxygen in its gas supply and introduces no flammable gas into the working environment. Most commercial salvors followed suit in the following decades, according to Hermans.
Bayesian (ex name Salute) was a 180-foot aluminum-hulled sailing yacht built in 2008. Bayesian’s sinking made headlines around the world, both for the unusual nature of the casualty and the high profile of the owner, British tech tycoon Mike Lynch. The ultra-modern megayacht departed Italy on August 14, 2024 with a premier guest list, including Lynch. The vessel went down five days later in a sudden squall while anchored off Sicily, killing Lynch, his teenage daughter, the chairman of Morgan Stanley International, Lynch’s U.S. lawyer, and others. Seven of the 22 people aboard died, while 15 were able to make it into a lifeboat and survived.
A criminal investigation focused on the actions of the crew is currently under way, led by local prosecutors. Some marine engineers and naval architects have also raised questions about design factors that may have contributed to the outcome, including the tall mast and the location of downflooding points. The Bayesian’s builder has vigorously defended the safety of the vessel’s design.
A much-anticipated technical report on the sinking of the Bayesian is due out from the UK Marine Accident Investigation Branch this week, and will reveal more evidence. The full completion of the parallel Italian investigation will have to wait until the wreck is hoisted back to the surface for inspection.