DEFENSE/Sonar system, torpedo tubes of Taiwan's sub prototype revealed

Taipei, Feb. 27 (CNA) The sonar system and torpedo tubes of Taiwan's first domestically built submarine prototype were seen in public for the first time late Monday when the ship was being moved to a dry dock to conduct final harbor acceptance tests (HAT).

Known as "Narwhal" in English and "Hai Kun" (海鯤號) in Chinese, the prototype has been undergoing harbor acceptance tests at the factory of shipbuilder CSBC Corp. in Kaohsiung since October after an unveiling ceremony in late September.

On Monday evening, the prototype was towed from the CSBC Corp. factory to nearby Jong Shyn floating dock No. 8 and then transferred to a nearby dry dock, where final HAT tests were being conducted Tuesday.

As the Narwhal was being moved out of the factory to the floating dock, a large number of spectators, including media, shot videos and photographs of the indigenous submarine that had only been seen publicly once before, at last year's Sept. 28 unveiling event.

During last year's event, the bow of the submarine, along with the torpedo tubes and other critical components, were concealed beneath a Republic of China (Taiwan) flag.

CSBC Chairman Cheng Wen-lon (鄭文隆) said at the time the measure was taken to prevent the disclosure of confidential parts of the submarine for security reasons, pending further testing.

When the prototype was moved Monday, many of these previously concealed parts were visible, including its intercept sonar, flank sonar array, and torpedo tubes.

The military did not explain why those elements were revealed this time after being previously covered.

There were some parts, however, including the Narwhal's tail, that were shielded from view at last year's ceremony and remained that way during the moving process Monday.

Shu Hsiao-huang (舒孝煌) from the government-funded think tank Institute for National Defense and Security Research (INDSR), said the sub's tail remained shielded because "enemy forces" could estimate the prototype's underwater speed and acoustic fingerprints by observing the number of its propellers, their angles, and structural designs.

Another INDSR scholar, retired navy captain Jiang Hsin-biao (江炘杓), told CNA that Tuesday's HAT tests at the dry dock are meant to make sure the sub's actual displacement is consistent with its original design.

Among the tests conducted will be an inclining test that is performed to determine the ship's stability and coordinates of its center of gravity.

Other tests during the final HAT process at the dry dock will focus on all of the ship's equipment, ventilation system, and engine system separately before running a comprehensive test by connecting the systems together, Jiang said.

Only after successful completion of the HAT tests will the prototype move on to sea acceptance tests (SAT), according to Taiwan's military and CSBC.

Huang Shu-kuang (黃曙光), the leader of Taiwan's Indigenous Defense Submarine (IDS) program responsible for the Narwhal launch, previously told local media that the prototype will complete both the HAT and SAT before being delivered to the Navy at some point before the end of 2024.

After completing the required combat readiness tests by the Navy, the Narwhal will hopefully be commissioned into the Navy next year, according to Huang.

The IDS program is also aiming to build another domestic submarine by 2027.

The construction of the domestic submarines means Taiwan's Navy will have a total of three combat-ready submarines by 2025 and four by 2027, including two existing Chien Lung-class (Sword Dragon) submarines purchased from the Netherlands in the 1980s.

Taiwan also possesses two World War II vintage submarines purchased from the United States in the 1970s, but they are now used exclusively for training purposes.