Kaichū type submarine
class of submarine
The Kaichū type submarine (海中型潜水艦, Kaichū-gata sensuikan) submarines were double-hulled medium-sized submarines of the Imperial Japanese Navy during World War II. The name was derived from the Kaigun-shiki Chū-gata Sensuikan (海軍式中型潜水艦, Navy Medium Type submarine).
Several variants existed. From 1934 to 1944, the K6 type (Ro-33 Class) and the K7 type (Senchū, Ro-35 Class) were built. They were equipped with a 76.2 mm (3.00 in) L/40 gun and four 53 cm torpedo tubes for ten type 95 Long Lance torpedoes.
Most of these submarines were destroyed in combat, suffering from Allied anti-submarine warfare measures, and only Ro-50 survived the war.
Class variants
The Kaichū type submarines were divided into seven classes:
Kaichū I (海中1型（呂一一型）, Kaichū-ichi-gata, Ro-11-class)
Kaichū II (海中2型（呂一三型）, Kaichū-ni-gata, Ro-13-class)
Kaichū III (海中3型（呂一六型）, Kaichū-san-gata, Ro-16-class)
Kaichū IV (海中4型（呂二六型）, Kaichū-yon-gata, Ro-26-class)
Toku-Chū/Kaichū V (特中型/海中5型（呂二九型）, Toku-Chū-gata/Kaichū-go-gata, Ro-29-class)
Kaichū VI (海中6型（呂三三型）, Kaichū-roku-gata, Ro-33-class)
Sen-Chū/Kaichū VII (潜中型/海中7型（呂三五型）, Sen-Chū-gata/Kaichū-nana-gata, Ro-35-class)
Kaichū I (Ro-11 class)
Project number S7. In 1910s, the Imperial Japanese Navy (IJN) bought a license of Schneider-Laubeuf design submarine. The IJN used the design as model and built the S Type (Schneider Type) submarine, the Ha-9 and Ha-10. The Kaichū I is the submarine which jumboized the S Type submarines.
Boats in class
Kaichū II (Ro-13 class)
Project number S18.
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