Kasashima-class salvage tugboat

The Kasashima-class salvage tugboats (笠島型救難船兼曳船,, Kasashima-gata Kyūnansen-ken-eisen) were a class of rescue ship / tugboat of the Imperial Japanese Navy (IJN), serving during World War II. The IJN official designation for this class was 600-ton salvage tugboat (六〇〇瓲救難船兼曳船,, 600-ton Kyūnansen-ken-eisen) for all vessels.

Class overview
Name	600-ton salvage tugboat
Builders	Harima Zōsen Corporation
Operators	Imperial Japanese Navy
Preceded by	Tategami class
Succeeded by	Miura class
Built	1937–1939
In commission	1938–1947 (?) [1]
Planned	2
Completed	2
Lost	1
Retired	1
General characteristics Kasashima class
Type	Salvage tugboat
Displacement	600 long tons (610 t) [2]
Length	40.0 m (131 ft 3 in) [2]
Beam	8.8 m (28 ft 10 in) [2]
Draft	4.3 m (14 ft 1 in) [2]
Propulsion	2 × reciprocating engines,[2] 2 × Kampon water tube boilers,[2] 2 shafts, Kasashima 2,033 ihp[2] Futakami 2,249 ihp [2]
Speed	Kasashima 14.14 knots (16.27 mph; 26.19 km/h) [2] Futakami 14.54 knots (16.73 mph; 26.93 km/h) [2]
Endurance	Fuel: Oil[3] and coal (?)

Background

Under the Russo-Japanese War, the IJN purchased many steamships and converted them to salvage vessels. However, when they entered in 1930s, deterioration became remarkable. The IJN initially planned for the Tategami class to succeed them. The IJN was going to build the Tategami class one by one for three years from fiscal year 1936. However, the plan came to an impasse due to budget shortages by the second year. The IJN postponed building of the second ship for two years, and built two cheap 600-ton ships instead: the Hashima (later renamed Kasashima) and Futakami.^[4]

Ships in class

Ship	Builder	Laid down	Launched	Completed	Fate
Kasashima (笠島) ex-Hashima (波島)	Harima Zōsen	15 December 1937	8 March 1938	27 May 1938 as Hashima	Renamed Kasashima on 25 October 1940;[5] sunk by aircraft off Taipei 26°22′N 120°56′E on 25 January 1944.[6]
Futakami (二神)	Harima Zōsen	21 October 1938	27 March 1939	30 April 1939	Survived war in Truk; decommissioned on 3 May 1947 (?);[1] later scuttled off Tonowas.