Japanese submarine Yu 22

History
Japan
Name	Yu 22
Builder	Hitachi Kasado Works, Kudamatsu, Japan
Fate	Surrendered August 1945 Scuttled or scrapped
General characteristics Yu I type
Type	Transport submarine
Displacement	274 long tons (278 t) surfaced 346 long tons (352 t) submerged
Length	41.40 m (135 ft 10 in) overall
Beam	3.90 m (12 ft 10 in)
Draft	3.00 m (9 ft 10 in)
Propulsion	2 × Hesselman engines 298 kW (400 bhp) surfaced 56 kW (75 shp) submerged single shaft
Speed	10 knots (19 km/h; 12 mph) surfaced 4 knots (7.4 km/h; 4.6 mph) submerged
Range	1,500 nmi (2,800 km; 1,700 mi) at 8 knots (15 km/h; 9.2 mph) surfaced 32 nmi (59 km; 37 mi) at 4 knots (7.4 km/h; 4.6 mph) submerged
Test depth	100 m (328 ft)
Capacity	24 tons freight or 40 troops
Complement	23
Armament	1 × Type 4 37 mm shipboard gun 5 × Type 99 light machine guns

Yu 22 was an Imperial Japanese Army transport submarine of the Yu 1 subclass of the Yu I type. Constructed for use during the latter stages of World War II, she served in the waters of the Japanese archipelago.

In the final two years of World War II, the Imperial Japanese Army constructed transport submarines — officially the Type 3 submergence transport vehicle and known to the Japanese Army as the Maru Yu — with which to supply its isolated island garrisons in the Pacific Ocean. Only submarines of the Yu I type were completed and saw service. The Yu I type was produced in four subclasses, each produced by a different manufacturer and differing primarily in the design of their conning towers and details of their gun armament. None carried torpedoes or had torpedo tubes. Yu 22 was a unit of the Yu 1 subclass.^[1]

The Hitachi Kasado Works (Hitachi Kasado Seisakujo) at Kudamatsu, Japan, constructed Yu 22.^[1][2] Records of the details of the construction of Yu 22 have not been discovered, but the earlier Yu I-type submarines were laid down and launched during the latter half of 1943 and entered service at the end of 1943 or early in 1944.^[2][3]

Yu 22 spent her operational career in Japanese home waters.^[4] Surviving records of the activities of Imperial Japanese Army submarines are fragmentary,^[3][5] and no records have been discovered describing her specific activities in support of any particular operation.^[2][4]

World War II ended with the cessation of hostilities on 15 August 1945. Yu 22 surrendered to the Allies later in August 1945.^[2] She subsequently either was scuttled or scrapped.^[4]

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