The death of the South Korean corvette "Cheonan" turned out to be such a complex story, in which truth, half-truth, fiction, lies and concealment of facts were intricately intertwined that even now, ten years later, it is not easy to understand it. Due to some political events, it acquired an anecdotal character in places. I do not see any tragedy in the death of the sailors - it was their duty and oath, especially since the corvette was located very close to hostile waters.
Corvette with combat experience
Corvette "Cheonan" (English name ROKS Cheonan, tactical number - PCC-772), class "Pohang". Displacement 1200 tons, length 88 meters. The maximum stroke is 32 knots. It was an anti-submarine corvette. On board are 6 torpedo tubes (Mark 46 torpedoes), 12 bomb throwers (Mark 9 depth charges), as well as two 76-mm cannons, two 40-mm cannons and four Harpoon anti-ship missile launchers.
The ship was launched in 1989, the fourteenth ship in the series, and entered the fleet the same year. On June 15, 1999, the corvette took part in the first battle off Yongpyendo Island (east of Pennyendo Island, near which the corvette later died, on the same Northern Delimitation Line). North Korean torpedo boats, patrol boat and patrol boats exchanged fire with South Korean corvettes and patrol boats. "Cheonan" fired from its 76-mm and 40-mm cannons, so the victory remained with the southerners. They succeeded in sinking a North Korean torpedo boat, seriously damaging the patrol ship and hitting the patrol boats. The Cheonan received minor stern damage.
So the ship had history and participation in a real battle. Which makes the whole story of his death even stranger. Nevertheless, the crew and especially the officers, some of whom could have served on the ship from the moment of that battle, were well aware that they were in the waters, where there could be any surprises from sworn compatriots, and there was some chance of being attacked.
Some hard facts
The oddities do not end there, but only envelop the story of the death of the corvette even more densely. In fact, in the whole heap of statements, reports and various information leaked to the press, there are very few facts that would have been firmly established.
The date, time and place are known. On March 26, 2010 at 21.33 hours local time, when the corvette was about a mile west of Pennyondo Island, a violent explosion occurred. Five minutes later, the corvette broke in two. The stern sank near the explosion site at a depth of 130 meters, and the bow was carried to the southern part of the island 3.5 miles from the explosion site, and it sank at a depth of 20 meters so that a small part of the hull protruded from the water. Of the 104 crew members, 46 people died; interestingly, all the officers survived.
Both parts of the corvette were then raised, examined and then placed in a naval memorial. The destruction was more than impressive and showed that the corvette had been destroyed by a powerful underwater explosion.
Reliable facts include a study of the seismogram of an underwater explosion made in 2014 by a group of researchers (Seo Gu Kim - Korea Seismological Institute, Efim Gitterman - Geophysical Institute, Israel, Orlando Rodriguez - University of Algarve, Portugal), who determined that the explosion power was 136 kg of TNT, the explosion occurred at a depth of 8 meters with a sea depth of 44 meters. This conclusion, by the way, refutes the opinion that the corvette ran into an old bottom mine, which was placed in the area in the 1970s. Bottom mines are loaded with a much larger explosive charge, up to a ton or more, and the calculated explosion power is more consistent with the torpedo charge.
Also, employees of the University of Virginia (USA) and the University of Manitoba (Canada) Son Hong Lee and Pansok Yang carried out a spectroscopic and X-ray structural study of samples of a substance taken from the tail of a torpedo (presumably North Korean), from the corvette's body and a control sample obtained during a test explosion. South Korean experts believed that the substance was aluminum oxide, formed during the explosion. However, X-ray diffraction analysis showed that this is not aluminum oxide; moreover, the data for three samples did not match and the third sample did not match the first two. Comparison with the control samples showed that the samples taken from the torpedo and corvette hull correspond to aluminum hydroxide, a substance that is not formed during an explosion, but is formed during the corrosion of aluminum in seawater, and for a long time. The researchers concluded that the South Korean report bears traces of falsification and is therefore invalid.
On this occasion, there was some polemics, in my opinion, unsuccessful: the parties remained unconvinced. It is understandable, because it was proved that the torpedo fragment presented by the South Koreans had nothing to do with the explosion under the corvette.
A paradoxical situation. It is known for sure that the corvette blew up and went to the bottom, but how and on what - it remained unclear.
Versions, versions …
You need to start with firmly established facts, so that later you do not become a slave to one of the versions, which, taking into account the objections, have been expressed a lot. The version makes up for the lack of firmly proven facts with various assumptions, completing the picture to some extent. But there were so few hard facts about the death of Cheonan that in the versions, assumptions and assumptions replaced facts.
There are three main versions.
First: a North Korean submarine sank a corvette with its torpedo. The version in South Korea is official, and was even used by the UN to demand the imposition of sanctions on the DPRK.
Second: the corvette ran into an old bottom mine, which exploded. This version was voiced at the beginning of the epic by the Ministry of Defense of South Korea.
Third: "friendly fire", that is, the corvette was sunk by a torpedo fired from an American submarine. This version was described in the most detail by the Japanese researcher Tanaka Sakai.
Of these, the first two versions can be deducted.
The North Korean version is not very suitable for purely technical reasons. The CHT-02D torpedoes used in the DPRK will not blow up the corvette the way it was blown up. This type of torpedo originates (directly or with Chinese mediation) from the Soviet SAET-50 torpedo, which in turn derives from the German T-V Zaunkönig torpedo, from which the acoustic homing system was taken. It follows that, firstly, the North Korean submarine needed to approach 600-800 meters to the corvette in order for the homing system to confidently take the target. Secondly, the system directs the torpedo to the noise of the propellers, and it explodes under the stern, in the area of the propeller-rudder group.
It is worth adding here that there is information that, on the whole, is not refuted, that together with the Cheonan there was the same type of Sokcho corvette - ROKS Sokcho (PCC-778), and it even fired at some target (this is the Ministry of Defense of the Republic of Kazakhstan already denied), and that the corvette or corvettes constantly used active sonar. So the northerners would not have been able to approach the distance of a confident shot, especially to two corvettes at once, without being detected. Shooting from afar is a waste of a torpedo. In addition, the corvette was blown up in the area of the engine room, and its propellers and rudders are intact (the propellers are slightly bent, but the cause of the damage is unclear; they may have been bent during lifting). That is, it was not a North Korean torpedo or a North Korean attack.
The bottom mine version has already been largely refuted by the indication of depths. Bottom mines can be set to a depth of 40-50 meters, and there were very large-scale underwater minefields in the area in the 1970s (Tanaka mentions the setting of 136 bottom mines). However, over time, the batteries are discharged and the mine becomes incapacitated. The mine placed at that time could no longer detonate anything in 2010, because it had been in the water for more than 30 years. Undermining a ship on an old and already incapable of exploding a bottom mine is possible only when the ship piles on it, which can only be in shallow water. Analysis of the seismogram of the explosion showed that under the keel of "Cheonan" was 44 meters, that is, this is not his case.
The version about the bottom mine was born in the Ministry of Defense of the Republic of Kazakhstan in the very first hours after reports that the bow of the corvette was found in shallow water near Pennyondo Island, and in conditions of an acute lack of information and the need to give at least some explanation of what happened, the version about the bottom mine - this is the first thing that comes to mind.
Now only the version about the American torpedo remains. Despite the fact that it looks very conspiratorial, and in the presentation of Tanaka Sakai it is also unreliable, because he assumes the death of an American submarine, which is easily refuted by comparison with the list of dead boats. It is impossible to hide the loss of a combat unit and the death of the crew.
Technically, I think, "friendly fire" is possible, since it better matches the picture of a ship blowing up. The Mark 48 torpedo has an active sonar guidance system, and, according to some reports, a device for responding to the ship's magnetic and electromagnetic fields. With this equipment, the torpedo really aims at the amidships of the ship and explodes under the keel where the magnetic and electromagnetic field of the ship is strongest, that is, in the area of the engine room, where the most massive steel parts are, where the generator is located.
Therefore, I believe that the version with "friendly fire" looks the most likely and it explains why this whole international scandal with accusations against the DPRK flared up. He had to cover up some of the unsightly sides of what had happened.
What could have happened?
I will compose my version of events based on the American one, but with amendments. It, like any version, provides for some logical reconstruction of events that are known to us extremely incompletely and inaccurately. In the case of the Cheonan corvette, only a tiny fraction of the really useful information reached the public, despite all the hype and multilateral commissions of experts.
In essence, my version boils down to the fact that on the evening of March 26, 2010, two South Korean corvettes and an American submarine met west of Pennyondo Island. Why they ended up in this area is unknown; this could have been part of the Key Resolve / Foal Eagle exercise that was taking place at the time (according to the Ministry of Defense of the Republic of Kazakhstan, the anti-submarine missions phase of the exercise took place elsewhere, 75 miles from the island; the ministry stated that Cheonan did not participate in the exercise), but could have been a separate operation, possibly related to reconnaissance tasks, in order to touch the northerners. In general, they met, they did not identify each other for some unknown reason. It can be assumed that the southerners discovered the boat's periscope, decided that it was a North Korean boat and fired at it. It is possible that Sokcho opened fire; it remained unclear whether he fired before the explosion or after. Apparently, they also intended to use depth charges. The American boat also did not identify the allied corvettes and, when it came under fire, considered them hostile ships, responding to the shelling with a torpedo shot. Shot and hit. Then the boat moved away to the island, about three miles from the explosion site, and may have been there for some time. In any case, Tanaka Sakai writes with references to South Korean sources about the discovery of a certain third underwater object, in addition to the sunken stern and nose of the corvette. Soon this object disappeared somewhere. If the boat did get damaged, then moving back to the island and patching up is a perfectly reasonable decision for the submariners. When the situation cleared up and the rescue operation began, the boat went to base.
In principle, this happens. Moreover, according to some information leaked to the South Korean press, the command was not that good. For example, the head of the Joint Chiefs of Staff of South Korea, General Lee Sang Ui, was drunk that evening, and so much so that he could not come to the command center, and then tried to hide it. The incident cost him his post, and he resigned in June 2010. Well, if the chief of the staff committee during large-scale (largest) military exercises so pawns for the uniform collar, then what is there to wonder that the allied ships at night at sea, near enemy waters, began to fire at each other?
The whole hysteria surrounding the death of "Cheonan" had a powerful political, primarily domestic political background: in this way, different parties and factions in the South Korean establishment were solving their problems. They were not at all embarrassed by the fact that they actually attributed a brilliant victory to the North Korean submarine fleet: the boat approached the anti-submarine corvettes unnoticed, thrust a torpedo into one of them, and left without being detected. Upper class! The memorial in which the Cheonan was installed after the ascent turned out to be, in fact, a memorial in honor of the North Korean submariners, where excursions were taken at the state expense, they told and showed how the North Koreans beat the South Korean fleet as they wanted.
Watching the hysteria in South Korea, I asked myself only one question: if there is a war, the northerners will drown the southerners in a bucket? So it turns out, or what?
So the official version (as if the corvette was sunk by a North Korean submarine) should be considered from a political point of view, since it is technically untenable and has caused numerous objections even in South Korea itself, to the point that skeptics were threatened with a repressive national security law.
There are many gaps and missing details in this story. And I can express confidence that we will know exactly about this only in decades, when the archives become available and some meticulous historian gets to them.
