Investigators will face a number of key questions as they probe the sinking of the British-flagged Bayesian off the coast of Sicily.
A body believed to be that of Mike Lynch's 18-year-old daughter Hannah was recovered from the wreckage of the luxury yacht off the coast of Sicily on Friday.
Mr Lynch, Hannah, Morgan Stanley International bank chairman Jonathan Bloomer, his wife Judy Bloomer, Clifford Chance lawyer Chris Morvillo, and his wife Neda Morvillo were all lost when the ship sank. If confirmed to be Hannah all missing passengers have now been found.The body of the yacht’s chef, Recaldo Thomas, was located shortly after the vessel sank.
Italian prosecutors have opened a criminal investigation. Investigators from the public prosecutor's office in the Sicilian town of Termini Imerese are collecting evidence for the probe.
The UK's Marine Accident Investigation Branch (MAIB) has deployed a team of inspectors to Italy.
The MAIB does not look to establish blame or liability but seeks to discover the causes of accidents at sea and prevent similar incidents in future.As investigators probe the aftermath of the incident, the Standard takes a look at key questions they will look into:
Did the yacht's design contribute to sinking?
The Bayesian has a mast measuring 72 metres, making it one of the largest in the world among sailing yachts.
Sam Jefferson, editor of the magazine Sailing Today, said the mast may have "acted almost like a sail" when severe weather hit the vessel, causing it to be "pinned over on its side".
Why did it sink so quickly and were the portholes open?
Mr Jefferson said he suspects "all the doors were open because it was hot", causing the yacht to fill with water "very quickly".
Weather records show temperatures reached around 33C the day before the sinking, which may have led to the vessel's occupants keeping access points open overnight.
Was the keel up? And if so, why?
Italian media reported that divers found the Bayesian's keel - a flat blade on the bottom of yachts that sticks down into the water to boost stability - was partially retracted.
Some yacht safety experts believe that may have contributed to the sinking.
But the Telegraph reported that a spokesperson for Italian Sea Group, which owns the company that built Bayesian, said: "Even without the keel completely out, the ship is stable and only a massive entry of water could have caused the sinking."
What measures did the crew take against the threat of bad weather?
Captain of the Bayesian, James Cutfield, told Italian media that he couldn't have foreseen the extent of the storm , saying “We didn't see it coming”.
Luca Mercalli, the president of the Italian Meteorological Society, said on Tuesday that the crew should have made sure that all the guests were awake and assigned them lifejackets, given the poor forecast.
Will the yacht be salvaged?
Nick Barke, head of salvage operations at Boats.co.uk, a boat sales and services company, said that the "only real way of knowing" why the yacht sank will be to lift it to the surface, but that would be "expensive and complicated process", likely to involve a crane barge.
He said divers would attach straps to the boat before it is lifted upright and then hauled out of the water.
He predicted this would be "time-consuming" as "they have to do it in such a way that they don't damage anything too badly."
What do witnesses on Bayesian know?
Investigators have already started to question witnesses, including the vessel's captain James Cutfield.
Obtaining witness testimony as soon as possible will be key for the authorities, experts say.
James Wilkes, a marine investigator, told Sky News those examining the sinking will want to speak to those who survived or saw what happened "while the memories are fresh in their mind".
"I'd like to explore the circumstances in which they were able to survive the storm and the sinking, to look at the anomalies and work out the difference between those and the people that sadly didn't survive, and combine it all with technical data and simulation,” he said.
How long will the investigation take, and what is the UK’s role?
Italian authorities are leading the investigation into the sinking of the superyacht.
A criminal investigation was opened immediately after the tragedy, although no suspects have been identified publicly.
Investigators from the public prosecutor's office in the Sicilian town of Termini Imerese are collecting evidence for the probe.
The UK’s Marine Accident Investigation Branch (MAIB) - a branch of the Department for Transport - has sent a team of investigators to the scene of the sinking, as Bayesian was British-flagged.
It will produce a report into why the sinking happened and may provide recommendations to prevent future occurrences.
The MAUB does not apportion blame.
