A complex investigation into a Labor Day weekend dive boat trip that ended in tragedy off Southern California will likely include a detailed timeline of events and attempt to answer why no one below deck was able to escape the fast-moving fire that left 34 people dead.
The probe continued as authorities announced Wednesday morning that they have recovered the bodies of 33 people who died in the fire. One person is still missing.
Coast Guard Lt. Zach Farrell said Wednesday that 13 bodies were recovered Tuesday.
The National Transportation Safety Bureau investigation will not only look at what led to the deadly fire near Santa Cruz Island, but also at possible lessons that might lead to changes in regulations for commercial vessels.
"Our mission here while we're on scene is to determine how this happened, why it happened and what safety improvements are needed to prevent it from ever happening again," said the NTSB's Jennifer Homendy.
The investigation team will likely reconstruct a timeline of events from the time the boat left Santa Barbara Harbor. As for evidence, a key piece -- the boat itself -- is on the sea floor about 60 feet below the surface. Crews were working to stabilize the wreckage Tuesday, but it was not immediately clear whether they were able to enter it.
Some evidence also might have been carried away by tides or destroyed in the the fire, George Zeitler, a former Coast Guard inspector who runs his own marine investigation firm, told the Associated Press.
"All of that will be a very large hurdle to overcome," said Zeitler. "It will definitely make for a complex investigation."
The fire is being treated as an accident. None of the evidence indicates there's anything "nefarious," said Santa Barbara County Sheriff Lt. Erik Raney.
The FBI and Bureau of Alcohol, Tobacco, Firearms and Explosives are part of the investigation team. The NTSB has about 15 investigators who specialize in engineering, operation and fire prevention. They're expected to be at the site for a week to 10 days, working with the Coast Guard and first responders.
One of the key questions investigators will look into is why no one below deck was able to escape the flames, Majorie Murtagh Cooke, the former director of the NTSB Office of Marine Safety, told the Los Angeles Times.
"With 30-plus people dying, the investigation could lead to changes in the way vessels are designed or protected depending on the findings," Cooke told the Times.
Coast Guard records show fire safety violations on the Conception in 2014 and 2016 were quickly fixed. There were no deficiencies found in February or August 2018 inspections.
The Conception, owned by Truth Aquatics, had left Santa Barbara Harbor Saturday for a diving trip. At about 3 a.m. Labor Day morning, frantic mayday calls were received, indicating that passengers were on the boat as it quickly burned.
The 75-foot vessel was chartered for three days by a commercial dive group based in Santa Cruz. They planned to explore the Channel Islands off the Southern California coast.
It appears the raging fire above deck blocked a stairway and emergency exit hatch from a below-deck area where 33 passengers and a crew member were sleeping in bunks, said Santa Barbara County Sheriff Bill Brown. It's not clear whether any alarms sounded or what the people below deck may have done to try to escape.
Five crew members, who were above-deck, apparently jumped from the bow. They were rescued by a nearby good Samaritan vessel.
"The entire boat was engulfed, from the bow to the stern and 30-foot flames," said Bob Hansen, the skipper of the vessel Grape Escape, which assisted with the rescue. "It was just terrible. It was just completely lit up. I mean, there wasn't a place on the boat that wasn't on fire."
Search-and-rescue crews were dispatched, but that mission turned into a recovery operation Tuesday when authorities announced that there were not signs of anyone surviving the fire, except for the rescued crew members. All 34 people below-deck were presumed dead.