The were a class of eight fast

torpedo boat A torpedo boat is a relatively small and fast naval ship designed to carry torpedoes into battle. The first designs were steam-powered craft dedicated to ramming enemy ships with explosive spar torpedoes. Later evolutions launched variants of se ...

s of the

Imperial Japanese Navy The Imperial Japanese Navy (IJN; Kyūjitai: Shinjitai: ' 'Navy of the Greater Japanese Empire', or ''Nippon Kaigun'', 'Japanese Navy') was the navy of the Empire of Japan from 1868 to 1945, when it was dissolved following Japan's surrender ...

built before and operated during

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...

Development

To circumvent the terms of the 1930

London Naval Treaty The London Naval Treaty, officially the Treaty for the Limitation and Reduction of Naval Armament, was an agreement between the United Kingdom, Japan, France, Italy, and the United States that was signed on 22 April 1930. Seeking to address is ...

, which limited its total destroyer tonnage the Imperial Japanese Navy designed the torpedo boat, but planned to arm it with half the armament of a destroyer. The resultant design was top-heavy and unstable, resulting in the 1934 ''Tomozuru'' Incident, in which one of the ''Chidori''-class vessels capsized. The subsequent investigation revealed the fundamental design flaw, and the four vessels in the class which had been completed were extensively rebuilt, and the remaining sixteen vessels projected were cancelled in favor of a new design which would address these design issues from the beginning. Sixteen ''Ōtori''-class vessels were ordered in the 1934

2nd Naval Armaments Supplement Programme The otherwise known as the "Circle Two" Plan was the second of four expansion plans of the Imperial Japanese Navy between 1930 and the start of World War II. Background The London Naval Treaty placed severe restrictions on Japan's naval capabi ...

, of which eight were completed between 1936 and 1937. The remaining eight were cancelled in favor of building additional

submarine chaser A submarine chaser or subchaser is a small naval vessel that is specifically intended for anti-submarine warfare. Many of the American submarine chasers used in World War I found their way to Allied nations by way of Lend-Lease in World War II. ...

s.The cancelled units, Torpedo boats #13 to #20 under the 1934 Programme, were projected to have been named ''Hatsutaka'', ''Aotaka'', ''Wakataka'', ''Kumataka'' ("bear hawk"), ''Yamadori'' ("mountain bird"), ''Mizudori'' ("water fowl"), ''Umidori'' ("seabird") and ''Komadori''; however, no contracts were placed by the time the order was changed in 1937 in favour of Submarine chasers #4 to #11.

Design

Benefiting from the redesign of the ''Chidori''-class, the ''Ōtori''-class had a slightly longer hull with an increased beam. The bridge structure was also lower than on the ''Chidori''-class to help keep the center-of-gravity low. Two

Kampon The was the externally operating division of the Ministry of the Navy of Japan responsible for the administration of naval vessel construction. From 1923 onward, it took on the role of a research institution for the research and development of n ...

geared turbines powered by two Kampon water-tube boilers produced a total of , which gave the ships more power than the ''Chidori''-class, and thus a slightly higher maximum speed of The armament of the ''Ōtori''-class was almost the same as for the rebuilt ''Chidori''-class with a

main battery A main battery is the primary weapon or group of weapons around which a warship is designed. As such, a main battery was historically a gun or group of guns, as in the broadsides of cannon on a ship of the line. Later, this came to be turreted ...

of three single

12 cm/45 3rd Year Type naval gun 12 cm/45 3rd Year Type naval gun was a Japanese naval gun and coast defense gun used on destroyers, and torpedo boats of the Imperial Japanese Navy during World War II. Design and development The 12 cm/45 gun designed in 1895 was an in ...

s which to elevate to 55 degrees for a limited anti-aircraft capability. The torpedo mount was upgraded from a twin to a triple torpedo launcher, and a single Type 94

depth charge A depth charge is an anti-submarine warfare (ASW) weapon. It is intended to destroy a submarine by being dropped into the water nearby and detonating, subjecting the target to a powerful and destructive Shock factor, hydraulic shock. Most depth ...

launcher was carried. However, anti-aircraft weaponry was only a single license-built Vickers 40 mm (2 pounder pom pom). During the

Pacific War The Pacific War, sometimes called the Asia–Pacific War, was the theater of World War II that was fought in Asia, the Pacific Ocean, the Indian Ocean, and Oceania. It was geographically the largest theater of the war, including the vast ...

, in 1944 survivors had the aft gun removed, and up to three twin-mount and five single-mount ''Type 96'' 25mm AA guns were installed as well as a Type 22 and a Type 13 radar. The number of depth charges was increased to 48.

Operational service

The ''Ōtori''-class were used extensively from the start of the Pacific War to escort invasion convoys to the Philippines, Dutch East Indies and the Solomon Islands. sank the during the

Solomon Islands campaign The Solomon Islands campaign was a major campaign of the Pacific War of World War II. The campaign began with Japanese landings and occupation of several areas in the British Solomon Islands and Bougainville, in the Territory of New Guinea, du ...

on 16 February 1943. Seven of the eight ships in the class were sunk by submarines or air attack in the Pacific or the

South China Sea The South China Sea is a marginal sea of the Western Pacific Ocean. It is bounded in the north by the shores of South China (hence the name), in the west by the Indochinese Peninsula, in the east by the islands of Taiwan and northwestern Phil ...

and only survived to the end of the war.

Ships in class

Notes

References

*''Collection of writings by Sizuo Fukui Vol.5, Stories of Japanese Destroyers'', Kōjinsha (Japan) 1993, *''Model Art Extra No.340, Drawings of Imperial Japanese Naval Vessels Part-1'', Model Art Co. Ltd. (Japan), October 1989, Book code 08734-10 *''The Maru Special, Japanese Naval Vessels No.39 Japanese Torpedo Boats'', Ushio Shobō (Japan), May 1980, Book code 68343-40

External links

Japanese "Otori" Class Torpedo Boats
{{DEFAULTSORT:Otori Class Torpedo Boat World War II naval ships of Japan