6th Fleet (Imperial Japanese Navy)
Despite these advantages, IJN submarines achieved remarkably little during World War II primarily having in hindsight suffered from the antiquated strategy of the Imperial Japanese Navy General Staff, who viewed submarines as little more than scouts whose main role was to locate and shadow enemy naval task forces in preparation for a decisive surface conflict. Maybe the IJN General Staff was slow to change as the submarines were generally slow to dive, easy to track with radar and sonar, difficult to maneuver underwater, and less sturdy than their German U-boat counterparts.
Scuttling
To prevent a Soviet inspection team from examining surrendered Imperial Japanese Navy submarines after World War II, the United States Navy conducted Operation Road's End, in which it scuttled 24 of the submarines in the East China Sea off Fukue Island on 1 April 1946. Nine more Japanese submarines followed on 5 April, and another six went down by early May. In addition, U.S. Navy submarines sank four surrendered Japanese submarines as targets in the Pacific Ocean near Hawaii in May and June 1946, and the Royal Australian Navy sank six or seven (sources differ) surrendered Japanese submarines in the Seto Inland Sea on 8 May 1946 in Operation Bottom.