The submarines of the Kaichu II sub-class were larger and had a greater range than the preceding Kaichu I subclass, but they had the same power-plant, so their greater size resulted in a loss of some speed.[1] They also had a modified conning tower, bow, and stern, and the stern was overhanging.[1] They displaced 7400NaN0 surfaced and 1003.10NaN0 submerged. The submarines were 70.1m (230feet) long and had a beam of 6.1m (20feet) and a draft of 3.68m (12.07feet). They had a diving depth of 30sp=usNaNsp=us.
For surface running, the submarines were powered by two 14500NaN0 Sulzer Mark II diesel engines, each driving one propeller shaft. When submerged each propeller was driven by a 600hp electric motor. They could reach 16.5kn on the surface and underwater. On the surface, they had a range of 6000nmi at ; submerged, they had a range of 85nmi at .
The submarines were armed with six 450mm 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 76.2abbr=onNaNabbr=on deck gun mounted aft of the conning tower.[1]
Ro-14 was laid down as Submarine No. 22 on 14 September 1918 by the Kure Naval Arsenal at Kure, Japan.[2] Launched on 31 March 1919,[2] she was completed and commissioned on 17 February 1921.[2]
Upon commissioning, Submarine No. 22 was attached to the Kure Naval District — to which she remained attached throughout her career — and was assigned to Submarine Division 13 and to the Kure Defense Division.[2] On 1 July 1921, she was reassigned to Submarine Division 15, remaining on duty in the Kure Defense Division.[2] Submarine Division 15 served in the Kure Defense Division until 1 December 1921 and again from 1 December 1922 to 1 December 1923.[2]
On 8 April 1924, Submarine No. 22 was conducting torpedo practice off Hiroshima, Japan, when mishandling of one of her torpedo tubes caused a torpedo to fire backward into the torpedo compartment, killing one crewman.[3] [4] [5] She headed back to base, and either later the same day[3] or on 9 April[5] (sources disagree) collided with the Imperial Japanese Navy special service vessel,[3] [4] [5] suffering no additional casualties[4] but incurring damage so serious that she was in danger of sinking.[5] However, she made port, was repaired, and returned to service.
Submarine No. 22 was renamed Ro-14 on 1 November 1924.[2] On 1 December 1926, Submarine Division 15 began another assignment to the Kure Defense Division that lasted through the end of Ro-14′s active service.[2]
Ro-14 was stricken from the Navy list on 1 September 1933.[2] She remained moored at Kure as a hulk after that, and was renamed Training Hulk No. 3063 on 7 March 1934.[2] She served on training duties through the end of World War II in August 1945, and was scrapped at Harima, Japan, in September 1948.[2]