'It's perplexing.' How did the Golden Ray ship capsize? Here's a look at possible answers

The gleeful rescue team that pulled four trapped crewmen from a capsized cargo ship off the Georgia coast left behind more than 4,000 cars and one big question: Why did the Golden Ray capsize?

"Amazing," said Capt. John Reed, commander of the Coast Guard Sector Charleston, after the last crewman was extricated from a hole drilled into the ship, which stretched the length of more than two football fields. "The best day of my career."

Peter Goelz, former managing director of the National Transportation Safety Board, said he thinks the ship could be cleaned up and running again quickly.

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Goelz, who isn't involved in the investigation, said he's not sure when the cause of the mishap will be known, but there are not many possibilities to explore.

"It's perplexing," Goelz told USA TODAY. "How do you get enough water in there to essentially sink the ship so quickly?"

Goelz said there appear to be no massive rocks in the dredged channel that could have torn a hole in the hull. The load of cars could have shifted, but he said it would take a major change in weight distribution to topple the 656-foot ship.

In this image released by the U.S. Coast Guard shows a crew member of the cargo ship Golden Ray as he is helped off the capsized ship Monday, Sept. 9, 2019 off St. Simons Island, Ga.
In this image released by the U.S. Coast Guard shows a crew member of the cargo ship Golden Ray as he is helped off the capsized ship Monday, Sept. 9, 2019 off St. Simons Island, Ga.

The Golden Ray is a "RoRo" – a roll on, roll off ship designed with massive doors so cars and trucks can be driven on and off. Another possibility is that one of those doors wasn't properly secured, Goelz said.

The NTSB provided two investigators, but the Coast Guard will handle the probe into what happened. No timeline for answers has been provided.

"It will be very interesting to see what they find," Goelz said.

The Baltimore-bound Golden Ray had barely set sail out of Brunswick, Georgia, and into St. Simons Sound early Sunday morning when trouble struck. An emergency call went out at around 2 a.m. EDT, and about two hours later, 20 crew members had been rescued.

That left four people to find, but the boat was unstable and a fire was raging, hampering rescue efforts. Monday morning, about 30 hours after the first emergency call, a helicopter landed on the side of the Golden Ray, and a team emerged. Rescuers heard tapping coming from inside the beleaguered ship.

At 1 p.m. Monday, it was confirmed that the four were alive. Rescuers cut a hole in the ship to provide more air and to drop food and water. A bigger hole was cut with special tools to ensure another fire was not sparked.

Three of the crewmen were freed from the engine room at around 3 p.m. The fourth rescue proved more complex. Three hours later, after rescuers penetrated blast-proof glass with a diamond-tipped cutter, the last man made a triumphant exit from the ship.

Tim Ferris of the salvage firm Defiant Marine told The Associated Press the South Korean sailors “were being cooked” in the engine room where temperatures reached 150 degrees. Ferris, who called the rescue "the effort of a lifetime," said rescuers had to stuff their own pockets with bags of ice to withstand the heat.

The ship is owned by the South Korean firm Hyundai Glovis. South Korean President Moon Jae-in sent letters to President Donald Trump and Adm. Karl Schultz, commandant of the Coast Guard, thanking them for the rescue effort, government spokesperson Ko Min-jung said. Ko lauded the crew members for overcoming their fear in the isolated space, clinging to hope that rescue would come.

"Thank you for returning to your families alive," she said.

This article originally appeared on USA TODAY: Golden Ray: How did the Korean cargo ship capsize near Georgia?