June 2, 2012: South Korea has ordered 18 American submarine launched Harpoon anti-ship missiles. The 546 kg (1,200 pounds) Harpoon has a 222 kg (487 pounds) warhead and a range of 220 kilometers. It approaches the target low, at about 860 kilometers an hour. GPS gets the missile to the general vicinity of the target and then the radar takes over to identify and hit the target. The Harpoon has successful combat experience going back two decades.
These are the first Harpoons South Korea has bought since 2006, when a batch of 58 Harpoon missiles were obtained. That was because South Korea had just introduced its own version of the Harpoon, the SSM-700K Haeseong. The South Koreans used the Haeseong in new warships it was building, instead of Harpoons. Originally, these new warships were designed to mount Harpoons but the Haeseong is similar enough, in size and capabilities, that switching will not be a major problem.
Haeseong was to replace Harpoon in South Korean submarines and aircraft as well. The submarine-launched version encountered some problems, or it may have been determined that it was cheaper to stick with Harpoon in the subs, mainly because of the high development cost of the submarine version. South Korea certainly has the capability to adapt the Haeseong for submarine use. The Haeseong is 32 percent heavier than Harpoon but is also 20 percent faster and has a shorter range (150 kilometers). In the last eight years South Korea has ordered about 150 Haeseongs.