CSBC Corporation, the shipbuilder behind Taiwan’s Hai Kun-class submarine programme, revealed that the initial boat completed its first submerged trials on 29 January, marking a key milestone in Taiwan’s indigenous submarine project.
The achievement follows a “pre-submerge” test on 26 January, during which the submarine’s sonar, propulsion system and diving instruments were validated. It was also the boat’s sixth sea trial.
CSBC told Taiwanese media that the initial phase of submerged testing will focus on snorkel- and periscope-depth operations at submerged depths of 10-20m. These trials are aimed at verifying watertight integrity, underwater trim, balance and stability. They will be followed by shallow-water submerged trials at depths of 50-100m.
Subsequent testing will progressively move into deeper waters, with trials expanding from 100m deep toward the submarine’s designed maximum operating depth.
Before delivery to the Republic of China Navy (ROCN) for shakedown and operational evaluation, CSBC will conduct a final phase of system-level technical assessments. These will include endurance trials, underwater acoustic performance, sonar functionality, combat system integration and simulated weapons launches.
CSBC said in its statement that the programme has faced persistent challenges since its inception. This is due to pressure from mainland China on international partners that have been supporting the effort.
Despite this, the company said it will continue to advance the Indigenous Defense Submarine programme through what it described as a problem-solving and adaptive development approach.
The initial boat Hai Kun was initially slated for delivery in October 2025, and the company has been fined by the government since last November, and these penalties will continue until the submarine is handed over to the ROCN.
by Chen Chuanren
