Hi convoys (ヒ) were a numbered series of World War II trade convoys between Japan and Singapore. Merchant ships from Moji and Kaibōkan from Sasebo formed southbound convoys in Imari Bay to carry supplies for the Burma Campaign. Northbound convoys transported food, petroleum, and raw materials to Japan from the captured European colonies of the Dutch East Indies, French Indochina, and British Malaya and Burma. These convoys were initiated in mid-1943 to protect fast, high-value tankers and troopships from the improved effectiveness of Mark 14 torpedoes carried by United States submarines.
IJN Shimushu was one of the Kaibōkan escorting Hi convoys.
Shimushu (占守) was the lead ship of her class of four escort ships built for the Imperial Japanese Navy during World War II.
Shimushu in 1940