Shimushu-class warships were developed for the Imperial Japanese Navy (IJN) primarily for the escort / destroyer escort role during World War 2, making them relatively compact vessels with the running gear needed to keep pace with their larger brethren. This meant good endurance and solid seakeeping traits to which the Japanese classified them as "Ocean Defense Ships". The class was built through four examples: IJN Shimushi, IJN Kunashiri, IJN Ishigaki, and IJN Hachijo and led to several refinements in the Japanese approach to escort ships.
Hachijo, the focus of this article, was constructed by the Sasebo Naval Arsenal with her keel laid down on August 3rd, 1939. She was formally launched on April 10th, 1940 and commissioned on March 31st, 1941. She, along with her sister Kunashiri, eventually survived the war and were decommissioned / scrapped shortly afterwards (Shimushu was handed over to the Soviet Union while Ishigaki was torpedoed by the submarine USS Herring back in May 1944).
As built, IJN Hachijo held a running length of 255 feet with a beam of 29.9 feet, and draught of 10 feet. Her shallow draught allowed for operations close-to-shore when needed. Power was from a twin-diesel engine arrangement generating 4,200 horsepower used to drive twin screws under the ship. Maximum speed in ideal conditions reached nearly 20 knots (19.7 kts). Range was out to 8,000 nautical miles.
Aboard was a complement of 150 personnel. Her profile included an elevated forecastle with flat-faced bridge superstructure. Behind the structure was the forward mast. At midships was the short-profile funnel, noticeably cranked to the rear, and this preceded the second mast. Towards the stern was a stepped arrangement between the superstructure and hull proper which gave proper firing arcs to the guns facing aft.
Armament consisted of 3 x 4.7" (120mm) /45 caliber main guns set in three single-gunned mountings - one over the forecastle and the remaining two positioned aft, facing rearwards, in stepped fashion. 6 x Initially she carried just 4 x 1" (25mm) Anti-Aircraft (AA) guns but this was enhanced to 15 guns before the end of the war. Six depth charge launchers were also installed and the charge load was increased from the original 12 to 25 as the war went on - up to 60 total charges before the end. The armament suite was rounded out by 1 x 81mm (3.2") mortar. Though originally finished with mine-sweeping equipment, this was later given up in May 1942 in favor of more depth charges to better deal with the American submarine threat plaguing Japanese shipping.
During her early-going, Hachijo was used in her given escort role by Japanese forces traversing the vast expanses of the Pacific. In July of 1944, the warship came under fire from American warplanes and took damage to her hull as well as backup engine facilities which caused flooding. Despite this, she survived and was able to complete her tour in the Second World War. The Empire of Japan capitulated in August of 1945, signaling the end of World War 2 in full.
Hachijo followed many other IJN ships who did not meet their fate at the bottom of the ocean in the war - she was stripped of her war-making usefulness and scrapped on April 30th, 1948.