USS Tarpon (SS-175), ULTRA Intelligence, and the Hunt for a Japanese Aircraft Carrier, October 20, 1943
In October 1943, the waters off the Japanese home islands were becoming increasingly dangerous for ships of the Imperial Japanese Navy. American submarines were pressing into the approaches to Honshu, threatening both merchant traffic and the major combatants of the Combined Fleet. Among them was USS Tarpon (SS-175), an older fleet submarine whose early reputation for operational misfortune had begun to give way to a record of aggressive patrols.
