Pohang (PCC Patrol Combat Corvette)The Pohang-class corvette PCC-772 Chonan [aka Cheonanham] sank in the Yellow Sea late on Friday 26 March 2010, in a tense maritime area disputed by North Korea. The incident involving the vessel with a crew of 104 forced South Korean President Lee Myung-bak to convene two emergency security meetings. The president ordered a "quick and thorough" investigation into the incident. At least 46 South Korean military personnel were missing soon after one of the South's naval patrol vessels sank. Seoul was investigating what caused the incident, but held off on blaming the North.
On Sunday, Defense Minister Kim Tae-young said that an underwater explosion appeared to have ripped apart the vessel, and a torpedo blast seemed the most likely cause. Investigators who examined salvaged wreckage separately announced Sunday that a close-range, external explosion likely sank it.
"Basically, I think the bubble jet effect caused by a heavy torpedo is the most likely" cause, Kim told reporters Sunday. The bubble jet effect refers to the rapidly expanding bubble an underwater blast creates and the subsequent destructive column of water unleashed.
Kim, however, did not speculate on who may have fired the weapon and said an investigation was ongoing and it's still too early to determine the cause.
Soon after the disaster, Kim told lawmakers that a North Korean torpedo was one of the likely scenarios, but the government has been careful not to blame the North outright, and Pyongyang has denied its involvement.
As investigations have pointed to an external explosion as the cause of the sinking, however, suspicion of the North has grown, given the country's history of provocation and attacks on the South.
The bubble-jet effect occurs when a torpedo or mine detonates in the water some distance away from the ship. The explosion creates a ``hole'' in the water, and due to the difference in pressure, this sphere collapses from the bottom.
This creates a "pillar'' of water that can rise up to 100 meters into the air, damaging a ship heavily. The water breaks a meter wide hole straight through the ship, flooding one or more compartments, and might break the ship apart.
How N.Korean Heavy Torpedo Could Have Sunk Cheonan
Defense Minister Kim Tae-young's comments on Sunday that a bubble jet caused by a heavy torpedo was the most likely cause of the blast that sank the Navy corvette Cheonan have put North Korean heavy torpedoes on the top of the list of suspects.
It is difficult to imagine a country other than North Korea launching a torpedo attack against a South Korean warship, and the extent of damage the Cheonan suffered has made a heavy torpedo the probable cause. Military experts believe North Korea has four types of heavy torpedoes: Yu-3G, ET-80A, TYPE 53-59, and the TYPE 53-56.
One source said if a North Korean torpedo was the culprit, it would most likely have been a Yu-3G. Developed in China during the mid 1980s, the Yu-3G is a "passive acoustic homing" torpedo that tracks the sounds of a vessel's propellers and its wake and attacks accordingly. Experts believe the North would have equipped the Yu-3G with a fuse that can be detonated by the magnetic field generated by a vessel.
The lower part of the Cheonan, beneath the gas turbine room where the external explosion is believed to have happened, is the part of a ship that produces the strongest magnetic field. When equipped with a 200 kg high explosive, the Yu-3G, with a range of 12 km, is said to be strong enough to split a warship the size of the Cheonan in half.
The ET-80A is also a passive acoustic homing torpedo with a range of 7.3 km. The Type 53-59 and Type 53-56 torpedoes, which were developed in the former Soviet Union and were exported to China and North Korea, are straight-track projectiles that travel in a straight line toward their targets after being fired.
South Korea's military says that military intelligence gathered with the United States shows that a torpedo fired from a North Korean submarine sank its navy ship Cheonan last month.The clearest sign yet that Seoul blames Pyongyang for what would be one of the deadliest incidents between the rivals since the end of the 1950-53 Korean War was reported by the publicy funded Yonhap news agency.A giant floating crane lifts the stern of the South Korean warship Cheonan. Photograph: HONG JIN-HWAN/AFP/Getty ImagesCertain Generals were Promoted after the sinking, after they had lost "Face in the last year's sea battle. Seems they have redeemed themselves and are preparing the way for Kim Jong-il's younger son. Do make sure your passports and documents are in order...it could hit the fan, people, be afraid, be very afraid.Some people are not fooled by the most dangerous government in the world.A new leader is being prepared for the North Korea people. Be prepared people, be prepared for ANYTHING.This was back in the 2000-2002 "honeymoon" stage with hopes of Reunification as one country. Sure, but will it be Communism or Republic? Some wish for Socialism, one wonders where Theirbrains are at.