iStock(SANTA CRUZ, Calif.) — The crew of the Conception immediately knew they were in trouble.

The fire that killed 34 people early Monday fully engulfed the ship in minutes, according to the Conception’s surviving crew members, who described a harrowing and horrific scene in the critical moments after their boat caught fire.

One crew member said he was sleeping on the top deck when he heard a loud noise, National Transportation Safety Board Member Jennifer Homendy told ABC News in a one-on-one on camera interview. He immediately realized the boat’s galley was engulfed by flames.

Crew members said they rushed to get to the 34 people sleeping below. They first attempted to go through the double doors leading to the galley, but were pushed back by fierce flames. They then went to the front of the boat and tried to break through its windows. When that didn’t work, they ultimately had to look out for their own safety.

“At some point because of heat, smoke and fire they had to jump off the boat,” Homendy said.

One crew member broke his leg in the process, Homendy said. Two others swam to the front of the boat and got to a skiff. They loaded the other survivors on board and then raced to the nearby boat, The Grape Escape. After unloading their friends onto the boat, the two crew members tried to go back to the Conception again to see if they could get to survivors.

By that point, the entire boat was fully engulfed.

Homendy said the crew members don’t know what started the fire. She said possible ignition sources include the electrical system, photography equipment, batteries, cameras and phones that were plugged in and charging when the fire broke out. At this point, the NTSB is not ruling anything out.

While they search for the cause, Homendy just toured the Vision, a similar sized boat owned by the same company, in order to see the bunk room and its emergency hatch. Homendy said she had to climb a ladder in the back and maneuver over the top bunk. She then tried to crawl through the hatch.

“In order for me to really get at it I had to kind of twist around and push it out,” she said.

She also said she tried to find the hatch with the lights off, simulating an escape during the middle of the night, and couldn’t see anything.

Homendy was blunt when describing how hard it would be for 34 people to escape through that hatch during a fire.

“I think it would have been very difficult,” she said.

“I think I’d have concerns [sleeping in those quarters].”

The only two ways to exit the bunk room each led to the same place — the galley that was on fire. That possible design concern is also now part of the investigation, and, ultimately, could lead to a change in federal regulations, she said.

A full report on what caused the fire is not expected for over a year.

Thirty-three of the 34 passengers who died in the fire have been recovered, authorities said Wednesday. The remains will have to be identified through DNA testing.

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