Oi Class, Japanese
Torpedo Cruisers (original) (raw)
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The Pacific War Online Encyclopedia | |
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| Tonnage | 5832 tons standard displacement |
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| Dimensions | 532' by 46'6" by 15'9"162.15m by 14.17m by 4.80m |
| Maximum speed | 31.7 knots |
| Complement | 439 |
| Aircraft | 1 catapult1 seaplane |
| Armament | 4 5.5"/50 guns4x2 25mm/60 AA guns10x4 Long Lancetorpedo tubes (no reloads) |
| Protection | 238.3 tons1.5" (38mm) + 1" (25mm) HT machinery belt1.1" (28mm) HT deck (machinery)1.8" (45mm) HT deck (magazines)0.8" (20mm) gun shields1.5" (38mm) + 0.5" (12mm) HT conning tower |
| Machinery | 4-shaft Mitsubishi-Parsons-Gihon turbines (90,000 shp)12 Kampon boilers |
| Bunkerage | 1260 tons fuel oil |
| Range | 4000 nautical miles (7400 km) at 14 knots |
| Modifications | 1942-9-9: Converted to fast transports. 4x4 torpedo tubes removed to make room for two Daihatsu landing craft and two depth charge rails with 9 depth charges each. 1944: Kitakamiconverted to carry 8 kaiten. Light AA armament increased to 10 25mm and 4 13mm/76 AA guns. Type 13 and Type 21 radar installed. |
The Ois were completed in 1920-21 as part of the _Kuma_class. They were converted to torpedo cruisers before the start of the war, and carried a massive arsenal of these weapons. Their development was supported by a new doctrine for night fighting tactics in which massive numbers of Long Lance torpedoes would be launched outside battleship gun range at night to ravage the American fleet as it approached Japan. For reasons of secrecy, the conversion was not to take place until the fleet was ordered to transition to a war footing, which took place on 15 August 1941.
The conversion removed the three aft 5.5" guns (leaving only the four forward guns) and added ten sets of quadruple torpedo tubes. The tubes had no reloads, but a rail system was installed to allow torpedoes to be shifted from one side of the ship to the other. The addition of so many torpedoes cost the ships almost five knots of speed and significantly reduced their endurance.
Following the battle of Midway, the ships were converted to fast transports by removing some of their torpedo tubes. Plans to remove additional tubes to make room for additional landing craft were never carried out, but Kitakamiwas eventually converted into a Kaitencarrier.
Units in the Pacific:
References
Gogin (2010; accessed 2013-3-19)
Lacroix and Wells (1997)
Whitley (1995)
The Pacific War Online Encyclopedia © 2006, 2008-2009, 2012 by Kent G. Budge. Index
