Citing the “Taiwan News” website the Tawainese Ministry of Defense that the National Chung-Shan Institute of Science & Technology (NCSIST) and the Dutch company RH Marine will be in charge to modernize the two Chien Lung-class submarines, SS-793 Hai Lung (Sea Dragon) and SS-794 Hai Hu (Sea Tiger). the two submarines entered in service in 1987 and 1988 respectively.

The aim of this upgrade is to extend the operational capabilities of the two submarines into late 2030, according to the Taiwanese Ministry of Defense.

The Chien Lung class of submarine, also known as the Hai Lung (Sea Dragon) class, was manufactured in the Netherlands for Taiwan. They are a modified version of the Dutch Navy’s Zwaardvis class which itself is based on the US Barbel class. It has a crew of 67 sailors including 8 officers. 

The Chien Lung class submarine has a length of 66.9 meters with an 8.4-meter-wide beam and can reach a speed of up to 20 knots when submerged. Their weapons systems are capable of launching up to 28 torpedoes from their six 533mm torpedo tubes. It can fire the AEG SUT 264 torpedo (dual-purpose – wire-guided, active/passive homing) produced by the German company Atlas Elektronik and the UGM-84 Harpoon anti-ship missile fitted with a solid-fuel rocket booster and encapsulated in a container to enable submerged launch through a torpedo tube.

The Chien Lung class submarines are fitted with diesel-electric propulsion systems that include three Bronswerk/Stork-Werkspoor RUB 215×12 diesel engine developing 4,500 hp.