USS Ardent (AM-340) - Sinking of The Japanese Submarine I-12

Sinking of The Japanese Submarine I-12

The highlight of her service during this period occurred on 13 November. Ardent and the frigate USS Rockford (PF-48) were escorting a six-ship convoy midway between Honolulu and the United States. At 12:32, Ardent's sonar picked up a submarine contact. Ardent attacked first at 12:41, firing a 24-charge "hedgehog" pattern, and again at 12:46 with a second "hedgehog" pattern. Rockford left her escort station to assist, and fired her first barrage of rockets from her "hedgehog" at 13:08; two explosions followed, before an underwater detonation rocked the ship.

Ardent carried out two more attacks and the frigate dropped 13 depth charges to administer the coup de grace. The resulting explosions caused a loss of all contact with the enemy submarine. Wreckage recovered on the scene—deck planks, ground cork covered with diesel oil, a wooden slat from a vegetable crate with Japanese writing and advertisements on it, pieces of varnished mahogany incribed in Japanese, and a piece of deck planking containing Japanese builders' inscriptions—indicated a definite "kill". Postwar research revealed the sunken submarine to be the Japanese submarine I-12, which had sailed from the Inland Sea on 4 October 1944 to disrupt American shipping between the west coast and the Hawaiian Islands. In sinking I-12, Ardent and USS Rockford unwittingly avenged the atrocity I-12 had perpetrated on 30 October when, after sinking the Liberty ship SS John A. Johnson, the submarine had rammed and sunk the lifeboats and rafts and then machine-gunned the 70 survivors. Among the ten men killed were five enlisted men of the merchantman's Navy armed guard detachment.