Taiwan's sub prototype towed to dry dock for final harbor acceptance tests

Kaohsiung, Feb. 27 (CNA) Taiwan's first domestically built submarine prototype was towed to a dry dock Tuesday where final harbor acceptance tests (HAT) are scheduled to be conducted.

Known as "Narwhal" in English and "Hai Kun" (海鯤號) in Chinese, the prototype has been undergoing HAT at a 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 in preparation for it to be transferred to a nearby dry dock, where final HAT tests will be conducted.

The transfer to CSBC Corp.'s dry dock began at around 1:30 p.m. Tuesday. Jong Shyn floating dock No. 8, where the Narwhal was first docked, opened its valves to allow its chambers to fill with water causing the dry dock to float lower in the water.

The floating dock then became submerged and that allowed the sub to be moved into position.

When the water was pumped out of the floating dock's chambers, the dry dock rose and the sub was subsequently lifted out of the water on the rising deck.

A boat later towed the submarine to CSBC Corp.'s dry dock at around 2:30 p.m.

A source told CNA that the Narwhal will begin a series of final tests at the dry dock.

Defense scholar and retired Navy captain Jiang Hsin-biao (江炘杓) told CNA that HAT tests at the dry dock are meant to ensure 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 the 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, according to Taiwan's military and CSBC.