Japanese submarine Ro-38

The submarines of the K6 sub-class were versions of the preceding K5 sub-class with greater range and diving depth.[1] They displaced 1,133 tonnes (1,115 long tons) surfaced and 1,470 tonnes (1,447 long tons) submerged. The submarines were 80.5 meters (264 ft 1 in) long, had a beam of 7 meters (23 ft 0 in) and a draft of 4.07 meters (13 ft 4 in). They had a diving depth of 80 meters (260 ft).[2]

For surface running, the boats were powered by two 2,100-brake-horsepower (1,566 kW) diesel engines, each driving one propeller shaft. When submerged each propeller was driven by a 600-horsepower (447 kW) electric motor.[3] They could reach 19.75 knots (36.58 km/h; 22.73 mph) on the surface and 8 knots (15 km/h; 9.2 mph) underwater. On the surface, the K6s had a range of 11,000 nautical miles (20,000 km; 13,000 mi) at 12 knots (22 km/h; 14 mph); submerged, they had a range of 45 nmi (83 km; 52 mi) at 5 knots (9.3 km/h; 5.8 mph).[1]

The boats were armed with four internal bow 53.3 cm (21.0 in) torpedo tubes and carried a total of ten torpedoes. They were also armed with a single 76.2 mm (3.00 in) L/40 anti-aircraft gun and two single 25 mm (1.0 in) AA guns.[1]

Ro-38 was laid down as Submarine No. 204 on 20 June 1942 by Mitsubishi at Kobe, Japan.[4] She was renamed Ro-38 on 1 November 1942,[4] and was provisionally attached to the Maizuru Naval District that day.[4] She was launched on 24 December 1942[4] and completed and commissioned on 24 July 1943.[4]

Upon commissioning, Ro-38 was attached formally to the Maizuru Naval District,[4] and on 31 July 1943 she was assigned to Submarine Squadron 11 for workups.[4] On 31 October 1943 she was reassigned to Submarine Division 34 in the 6th Fleet, and she departed Maizuru bound for Truk that day. She arrived at Truk on 8 November 1943.[4]

Ro-38 got underway from Truk on 19 November 1943 to begin her first war patrol, assigned a patrol area in the Gilbert Islands in the vicinity of Makin and Tarawa.[4] The Japanese never heard from her again.[4]

On 20 November 1943, the Battles of Makin and of Tarawa began with the U.S. landings on those atolls. That day, the commander-in-chief of the 6th Fleet, Vice Admiral Takeo Takagi, ordered Ro-38 and the submarines I-19, I-21, I-35, I-39, I-40, I-169, I-174, and I-175 to attack the U.S. invasion fleet off the atolls.[4] On 26 November 1943, Takagi ordered I-19, I-40, I-169, and Ro-38 to form a patrol line north of Makin, with Ro-38 northeast of Makin at the eastern end of the line.[4] The 6th Fleet ordered Ro-38 to move to a new patrol area southeast of Tarawa on 27 November 1943,[4] and on 4 December 1943 it sent her orders to patrol between Tarawa and Canton Island.[4] Ro-38 did not acknowledge any of these orders.[4]

The circumstances of Ro-38′s loss are unknown. It is possible that the United States Navy destroyer USS Cotten (DD-669) sank her west of Tarawa on 24 November 1943.[4] On 2 January 1944, the Imperial Japanese Navy declared her to be presumed lost off the Gilbert Islands with all 77 hands.[4] She was stricken from the Navy list on 30 April 1944.[4]

• Bagnasco, Erminio (1977). Submarines of World War Two. Annapolis, Maryland: Naval Institute Press. ISBN 0-87021-962-6.
• Carpenter, Dorr B. & Polmar, Norman (1986). Submarines of the Imperial Japanese Navy 1904–1945. London: Conway Maritime Press. ISBN 0-85177-396-6.
• Chesneau, Roger, ed. (1980). Conway's All the World's Fighting Ships 1922–1946. Greenwich, UK: Conway Maritime Press. ISBN 0-85177-146-7.
• Hackett, Bob; Kingsepp, Sander (2017). "IJN Submarine RO-38: Tabular Record of Movement". SENSUIKAN! Stories and Battle Histories of the IJN's Submarines. Combinedfleet.com. Retrieved 20 September 2020.
• Hackett, Bob; Sander Kingsepp (2003). "Kaichu Type". Sensuikan!. Combinedfleet.com. Retrieved 20 September 2020.
• Hashimoto, Mochitsura (1954). Sunk: The Story of the Japanese Submarine Fleet 1942 – 1945. Colegrave, E.H.M. (translator). London: Cassell and Company. ASIN B000QSM3L0.