Experts hold an urgent discussion on the final report of the Cheonan sinking published by the Ministry of Defense at the National Assembly on Sept. 15. (Photo by Park Jong-shik)

They contend the reported damage in the JIG report does not match the Cheonan¡¯s hull

¡¡¡¡¡¡

Three academics who have been consistently questioning the findings of the Joint Investigation Group (JIG) that investigated the Cheonan¡¯s sinking met with foreign correspondents in Washington, D.C. on Sunday (local time). There, they raised the possibility that the sinking resulted from a mine explosion rather than a North Korean torpedo.

¡°A close-distance torpedo explosion at a depth of seven meters with a force equivalent to 360kg of TNT, as reported by the JIG, should be accompanied by a water column of about 80 meters in height as a result of the bubble effect and torpedo fragments embedded deeply in the hull,¡± said Suh Jae-jung, professor of the Johns Hopkins University School of Advanced International Studies. ¡°The JIG¡¯s simulation, however, was unable to confirm this at all. In spite of their own conclusions, the JIG experimented with an explosion equivalent to 100kg of TNT at a distance of 20 meters from the vessel and determined that the hull could become damaged as the resulting wave surged up and down.¡±

Suh and the other academics, Brookings Institute visiting fellow Park Sun-won and University of Virginia Physics Professor Lee Seung-hun, claimed that the ¡°close-distance explosion¡± bubble simulation performed by the JIG gave damage completely different from what actually happened to the Cheonan, rupturing the central portion of the vessel where the gas turbine room was located. In contrast, they said, a ¡°long-distance explosion¡± would correspond almost exactly with the damage to the vessel, with the central portion breaking away and the vessel broken into three parts.

Based on this, the academics raised the possibility that a mine on the sea floor was dragged up by a net tangled in the propeller screw and exploded from a physical collision.

¡°In the case of a long-distance explosion resulting from a mine, the wave¡¯s height would be just 10 meters or so, and there would be no chemical smell,¡± Suh said. ¡°It explains all of the phenomena that the torpedo explanation cannot.¡±

Meanwhile, Lee noted, ¡°In the appendix of the final report, there are energy dispersive spectroscopy (EDS) data showing that the adhesive material taken from the torpedo was not the aluminum oxide produced in an explosion but aluminum hydroxide,¡± a type of rust resulting from corrosion.

Also, Park said that he had acquired a record of the Cheonan¡¯s path.

¡°The final report states that a North Korean submersible fired a torpedo from 2.5km southwest of the site where the Cheonan went down, but that region is an area where the Cheonan had been just a few hours before,¡± said Park. ¡°Supposing a North Korean submersible did infiltrate that location, it could not have escaped being detected by the Cheonan¡¯s sonar.¡±

All three academics commented on the numerous problem areas of the JIG report, including contradictory findings, and stressed the need for another examination through a parliamentary inquiry or a similar measure.

In response, Army Brigadier General Yoon Jong-sung, who is head of the Defense Ministry¡¯s investigation headquarters and has been handling duties related to the Cheonan since the JIG was disbanded, suggested having an open discussion on the matter in South Korea.

¡°According to the simulation findings, an explosion at a depth of more than nine meters from the hull would not have had enough explosive force to sink the Cheonan,¡± Yoon said.

Yoon also noted, ¡°The adhesive substance [aluminum oxide] that had been stuck to the Cheonan¡¯s hull following salvage has now been washed clean away, apparently by rain.¡±

¡°If it were aluminum hydroxide from corrosion, it should still be on the hull,¡± he added.

¡¡¡¡

Please direct questions or comments to [englishhani@hani.co.kr]

¡¡