JINDO, South Korea (AP) - Frustrated relatives of the scores of people still missing from the sinking of the ferry Sewol held the fisheries minister and the coast guard chief overnight, angry about the pace of divers who have recovered 183 bodies so far but may have nearly 120 left to find in the dark rooms of the submerged vessel.
Scrutiny about the wreck's cause, meanwhile, has turned to what the ferry was carrying: more than 3,600 tons of cargo, according to the company that loaded it. An inspector that examined the vessel during a redesign said it could safely handle only about 1,000 tons of cargo and passengers, and needed more than 2,000 tons of water as ballast to ensure it remained balanced.
A naval architecture expert said Friday that the reported load could have set the ship tipping over with a significant turn. Tracking data show that the ship turned 45 degrees before sinking, and crew members have reportedly said that they had tried to make a much less severe turn.
"The ship would suddenly fall even with just a small turn. It should not make a sharp turn," said Lee Kyu Yeul, professor emeritus in ship and offshore plant design at Seoul National University's Department of Naval Architecture and Ocean Engineering. "It should make a huge circle with 1 or 2 degrees of turn, but (the Sewol) made a small circle. So it fell.
Prosecutor Yang Jung-jin of the joint investigation team said Friday that the cause of the sinking could be due to excessive veering, improper stowage of cargo, modifications made to the ship and tidal influence. He said investigators will determine the cause of the accident by consulting with the experts and simulating.
Prosecutors have raided and seized documents at Korean Register of Shipping, which conducted the redesign inspection, and the Korea Shipping Association, which regulates and oversees departures and arrivals of domestic passenger ships, according to officials at both organizations who asked to be anonymous because they were not authorized to speak about matters under investigation.
On Jindo island, where families have been waiting for more than a week for word of their loved ones, Oceans and Fisheries Minister Lee Ju-young, coast guard chief Kim Seok-kyun and deputy chief Choi Sang-hwan on Friday morning were able to leave the tent where the families had kept them. The tent is where officials post information about the newly recovered dead.
Dozens crowded around the grim-faced officials, who sat on the ground and tried to explain the search efforts. One man threatened to punch reporters gathered near the tent. Relatives occasionally shouted, accusing the officials of lying about the operation.
"We are doing our work and we, too, feel the way you do," Kim said Thursday. "We are trying to bring all the equipment that we can."
The ferry sank April 16 on its way from Incheon port to the southern tourist island of Jeju. More than 80 percent of the 302 dead and missing are students from a single high school in Ansan, south of Seoul.
Eleven crew members, including the captain, have been arrested on suspicion of negligence and abandoning people in need.
The coast guard said Capt. Lee Joon-seok reported in paperwork submitted to the Korea Shipping Association that the Sewol was carrying 150 cars and 657 tons of other cargo. That was clearly wrong: The coast guard has counted 180 cars in the water.
Moon Ki-han, a vice president at Union Transport Co., which loaded the Sewol's cargo, said it was actually carrying an estimated 3,608 tons of cargo. That is less than the 3,963-ton capacity that the coast guard says shipowner Chonghaejin Marine Co. Ltd. reported. But is far more than a Korean Register of Shipping report said was safe.
The report, produced during 2013 renovations that allowed the Sewol to carry more passengers, said that the changes cut the maximum load of cargo and passengers by more than half, from 2,525 tons to 1,070 tons. The amount of water ballast needed nearly doubled, from 1,023 tons to 2,030 tons.
The register document, released by lawmaker Kim Yung-rok of the New Politics Alliance for Democracy, an opposition party, shows redesign made the ferry 187 tons heavier, and raised its center of gravity 51 centimeters (20 inches).
"That is not good for the ship's stability," said Lee, the ship design professor.
The company's stated maximum tonnage was the same 3,963 tons stated by the ferry's previous Japanese owner, "A'' Line Ferry Co., before the vessel was modified, according to Takaharu Miyazono of "A'' Line.
It was unclear why the earlier maximum tonnage noted in the register document was lower than that provided by either Chonghaejin or the previous owner.
Officials with South Korea's maritime ministry and coast guard each said they were not aware of the Sewol's cargo capacity, and that it was the shipping association's job to oversee it. The shipping association is private and is partly funded by the industry it regulates.
An official at Korea Shipping Association declined to talk to media by phone, saying the association is under investigation by prosecutors.
Even the report by the inspector reflects "a problem in the system," said Lee Gwee Bok, president of Incheon Port Development Association and a former captain. He said the Sewol never should have been cleared for operation because the register should have known the shipowner would never meet the conditions.
"The ship's operator aims to make money and instinctively tries to add more freight," Lee said.