SACRAMENTO (CBS13) – The National Transportation Safety Board’s preliminary report into what caused the deadly dive boat fire on Labor Day did not determine a cause, but we now know the entire crew was asleep when the fire started.

34 people died on board the Conception, off the coast of Santa Barbara. The 21 women and 13 men, including one crew member, were all sleeping below deck and couldn’t escape because the ladder leading to the upper decks was on fire. The five surviving crew members were asleep on the uppermost deck. According to the two-page report,

“A crewmember sleeping in the wheelhouse berths was awakened by a noise and got up to investigate. He saw a fire at the aft end of the sun deck, rising up from the salon compartment below. The crewmember alerted the crew behind the wheelhouse. As crewmembers awoke, the captain radioed a distress message to the Coast Guard.”

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The report goes on to say that the crew immediately tried to get to the salon, on the main deck, and to the passengers below but they couldn’t use the ladder. The crew then jumped to the main deck and one member of the crew broke his leg. At that point, the salon and galley were both fully engulfed in flames and thick smoke covered the forward end of the boat. The crew tried to open a forward window but could not. They were then overcome with smoke so they jumped overboard.

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The captain and two members of the crew then, according to the report, “swam to the stern, reboarded the vessel, opened the hatch to the engine room, and saw no fire.” The crew then launched a small skiff and picked up the other two crew members in the water before boarding the nearby Grape Escape. Two crew members then returned to the Conception to look for survivors.

The NTSB will know more once the Conception is salvaged and inspected. They are also reviewing documents from all Coast Guard inspections, along with visiting the Vision, which is also owned by Truth Aquatics and is similar to the Conception.

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The NTSB is the lead federal agency investigating the cause of the fire and is being assisted by the Coast Guard, Truth Aquatics, Inc., the Santa Barbara County Sheriff’s Office, and Santa Barbara County Fire Department.