Japanese submarine Ro-103

History
Japan
Name	Submarine No. 213
Builder	Kure Naval Arsenal, Kure, Japan
Laid down	30 June 1941
Renamed	Ro-103
Launched	6 December 1941
Completed	21 October 1942
Commissioned	21 October 1942
Fate	Missing after 28 July 1943
Stricken	1 November 1943
General characteristics
Class and type	Ro-100-class submarine
Displacement	611 tonnes (601 long tons) surfaced 795 tonnes (782 long tons) submerged
Length	60.90 m (199 ft 10 in) overall
Beam	6.00 m (19 ft 8 in)
Draft	3.51 m (11 ft 6 in)
Installed power	1,000 bhp (750 kW) (diesel) 760 hp (570 kW) (electric motor)
Propulsion	Diesel-electric 1 × diesel engine 1 × electric motor
Speed	14.2 knots (26.3 km/h; 16.3 mph) surfaced 8 knots (15 km/h; 9.2 mph) submerged
Range	3,500 nmi (6,500 km; 4,000 mi) at 12 knots (22 km/h; 14 mph) surfaced 60 nmi (110 km; 69 mi) at 3 knots (5.6 km/h; 3.5 mph) submerged
Test depth	75 m (246 ft)
Crew	38
Armament	4 × bow 533 mm (21 in) torpedo tubes 2 × 25 mm (1 in) Type 96 anti-aircraft guns or 1 × 76.2 mm (3.00 in) L/40 AA gun

Ro-103 was an Imperial Japanese Navy Ro-100-class submarine. Completed and commissioned in October 1942, she served in World War II, operating in the Solomon Islands, Rabaul, and New Guinea areas and sinking two cargo ships. She disappeared in July 1943 during her fifth war patrol.