The peacetime role included fisheries patrol around the Kuril Islands. Minesweeping and convoy escort were wartime tasks, with trade and movement at sea central to the newer ships' purpose. The quantity of anti-submarine equipment provides an argument about design intent. A patrol ship could manage with a small gun battery, some anti-aircraft weapons and a limited depth-charge allowance. Six throwers and the larger stock of charges exceeded what that narrow role required, and even what many destroyers carried. On this reading, anti-submarine escort work mattered substantially to the design.
Chapter · 10:00-12:26
Fisheries patrol, minesweeping and convoy defence
Six depth-charge throwers and a substantial ammunition allowance suggest that anti-submarine escort work was central to a design also intended for fisheries patrol.