Taiwan has decided to build its own submarines. Since the 1990s Taiwan has been trying to buy new submarines to replace its existing and rapidly aging boats. In 2011 is was first suggested that Taiwan build its own. There were rumors that Taiwan was quietly arranging to have European submarine building experts accept contracts to discreetly work in a Taiwanese shipyard for a while. Meanwhile, some European builders were said to have agreed to train Taiwanese welders in the specialized type of welding used on submarines. Other negotiations were under way to purchase a wide array of specialized components needed for diesel-electric submarines. Some shopping took place in the United States, but the Americans have only built nuclear subs for the past half century, and the best technology for diesel-electric sub construction is now found in Western Europe. Threats from China and lack of enthusiasm in Taiwan for the cost of building subs locally led this effort to fade. But in the meantime Taiwanese subs are getting older. That and growing nervousness about the expanding capabilities of the Chinese Navy led to a change of attitude in Taiwan and the creation of the IDS (Indigenous Defense Submarine) program.
IDS is a response to the fact that Taiwan is running out of time to find replacements for its aging submarine force. Taiwan currently has four boats. Two are World War II era American Guppy class subs from 1945. These are used only for training and are increasingly difficult and expensive to maintain. Despite that the crews work hard to keep these museum pieces looking good and still operational. The two Hailung class subs were built in Holland and entered service in 1986. These 2,500 ton boats are armed with twenty torpedoes and Harpoon missiles (launched from the torpedo tubes.) But there's a new problem as well because of plummeting morale among the 200 sailors who run these boats. Years of delays in obtaining new subs, and dim prospects of ever getting them, discourages qualified young sailors from volunteering for the submarine service and many old hands are retiring as soon as they are eligible.
Taiwan now admits that the search for a shipyard willing to build them eight diesel-electric submarines failed. None of the European shipyards that specialize in this sort of thing would do it, as they feared economic retaliation from China. The United States had not built a diesel electric sub since the 1950s. Getting an American shipyard up to speed on building diesel electric subs turned out to be too expensive. The 2011 effort did compile a lot of useful information on costs and the more reliable (resistant to Chinese threats) suppliers. It turned out that a lot of American manufacturers could produce components for diesel electric subs even though most of their regular work is for nuclear boats. But aside from the nuclear propulsion, a sub is a sub and the American were willing to supply Taiwan.
Alternative solutions were investigated. Publicly, Taiwan says it wants the subs for anti-submarine work. But it's been pointed out that there are cheaper and more effective anti-sub capabilities available via helicopters, aircraft and, UAVs. What is left unsaid is that the subs could also be used to shut down China's ports, crippling the economy and causing lots of political problems for China's leaders. It's also possible to shut the ports without using subs (air dropped naval mines or just threatening to attack any merchant ship entering Chinese waters), but nothing does this sort of thing as effectively as a submarine, especially a very quiet diesel-electric sub.
Ideally, Taiwan wants eight new diesel-electric boats, preferably with AIP (air independent propulsion). This would drive the price up to nearly a billion dollars a boat. Building them in Taiwan can also be helped by other nations threatened by Chinese naval power. India, Japan and South Korea all build subs and have local suppliers willing to provide Taiwan with components and technical assistance. So it appears that Taiwan can get away with building the subs locally. While European firms won't sell Taiwan submarines they are apparently less reluctant to quietly sell components and training. The IDS effort could still fail, especially when the detailed cost estimates are presented to parliament. But if Taiwan wants to save its submarine capability it’s now or never and IDS is the last best hope.