Japanese submarine Ro-22

Ro-22, originally named Submarine No. 40, was an Imperial Japanese Navy Kaichū-Type submarine of the Kaichū III subclass. She was commissioned in 1922 and operated in the waters of Japan. She was stricken in 1934.

Design and description

The submarines of the Kaichu III sub-class were a slightly improved version of the preceding Kaichu II subclass, the man difference being an increase in diving depth from. They displaced surfaced and submerged. The submarines were long and had a beam of and a draft of.
For surface running, the submarines were powered by two Sulzer Mark II diesel engines, each driving one propeller shaft. When submerged each propeller was driven by a electric motor. They could reach on the surface and underwater. On the surface, they had a range of at ; submerged, they had a range of at.
The submarines were armed with six torpedo tubes, four internal tubes in the bow and two external tubes mounted on the upper deck, and carried a total of ten Type 44 torpedoes. They were also armed with a single [8 cm/40 3rd Year Type naval gun|] deck gun mounted aft of the conning tower.

Construction and commissioning

Ro-22 was laid down as Submarine No. 40 on 20 January 1921 by the Yokosuka Naval Arsenal at Yokosuka, Japan. Launched on 15 October 1921, she was completed and commissioned on 10 October 1922.

Service history

Upon commissioning, Submarine No. 40 was attached to the Yokosuka Naval District, to which she remained attached throughout her career. On 16 October 1922, she was assigned to Submarine Division 5 and to the Ominato Defense Division, and on 1 November 1924 she was renamed Ro-22. On 1 November 1925, Submarine Division 5 was reassigned to the Yokosuka Defense Division, then directly to the Yokosuka Naval District on 1 December 1926, and then to the Yokosuka Defense Division again on 10 January 1927. Ro-22 was stricken from the Navy list on 1 April 1934.