UK tech mogul Mike Lynch’s yacht Bayesian was named after a mathematical model for calculating risk. But, no one could have predicted the destruction that a pre-dawn storm would bring to the 184-foot sailing ship Monday and the 22 revelers aboard. Just after 4 a.

m., lightening began to flare over the warm waters off the coast of the Italian island of Sicily. Within minutes, a squall of tornado-like waterspouts pummeled the superyacht where it was anchored in Porticello harbor.

“We didn’t see it coming,” Bayesian’s captain James Catflield told La Repubblica from a hospital bed Tuesday, hours after the ship sank in 160 feet of water. Fifteen people — including Lynch’s wife, and a mother and her 1-year-old baby — managed to escape. Six passengers were still missing as of Wednesday morning local time: Lynch, 59; his 18-year-old daughter Hannah; New York City attorney Christopher Morvillo and his wife Neda; and Morgan Stanley exec Jonathan Bloomer and his wife Judy.

The body of chef Ricardo Thomas — one of the ten crew members – was the only known fatality. Lynch — who was dubbed “Britain’s Bill Gates” — had invited his guests onboard the yacht for a grand celebration over his acquittal of multibillion-dollar fraud charges following a federal trial in San Francisco. Lynch was accused of scheming to increase the valuation of his company Autonomy before he sold it to Hewlett-Packard in 2011 for $11 billion.

After the sale, HP wrote off $8.8 billion from.