After 13 years of negotiations, delays and finally construction Indonesia has launched the first of three South Korean Chang Bogo class submarines in late March. This boat will enter service in 2017 followed by the second in 2018. The third boat is to be built in Indonesia with South Korean help. Chang Bogo is an improved version of the German Type 209, but built in South Korea under license. The South Korean Navy put nine locally built Chang Bogos into service between 1993 and 2001. It is a proven design and that was a major selling point.
The Chang Bogos are 1,200 ton boats that are 55.9 meters (174 feet) long, have a top speed while submerged of 39 kilometers an hour, and a top surface speed of 20 kilometers an hour. Range is 20,900 kilometers at a surface speed of 7.4 kilometers an hour. Endurance is 50 days and the highly automated boat has a crew of only 31. Armament is 14 torpedoes fired from eight 533mm (21 inch) tubes.
Since 2003, when Indonesia began looking for ways to expand its submarine force and replace two 1980s era German subs, South Korea has been the leading candidate to supply the new subs. The first obstacle Indonesia ran into was the high cost of replacement boats. New subs cost over half a billion dollars each, although Russia was offering better prices on new Kilos. But Indonesia had a bad experience with Russian subs back in the 1960s. The two German type U209 boats they bought in the 1980s had proved sturdy, effective and durable. But these are now old boats. So Indonesia made a deal with South Korea, which also operates German subs, to refurbish their two boats. The first one took two years, but in addition to replacing worn parts and checking for any hidden damage, lots of new navigation and weapons systems were installed. The two German boats will thus be good for at least another ten years. The second of the two Type 209s completed their refurbishment in 2011 and at that point Indonesian Navy had finally obtained the money for new subs 209s (Chang Bogos).
South Korea was eager to get the business, as South Korean shipyards are building more warships, including subs. Doing the Indonesian refurbs at a favorable price made South Korea a leading contender to supply Indonesia with new boats.