Japanese submarine Ro-40

History
Japan
Name	Submarine No. 206
Builder	Mitsubishi, Kobe, Japan
Laid down	8 August 1942
Renamed	Ro-40 on 5 February 1943
Launched	6 March 1943
Completed	28 September 1943
Commissioned	28 September 1943
Fate	Sunk 16 February 1944
Stricken	30 April 1944
General characteristics
Class and type	Kaichū type submarine (K6 subclass)
Displacement	1,133 tonnes (1,115 long tons) surfaced 1,470 tonnes (1,447 long tons) submerged
Length	80.5 m (264 ft 1 in) overall
Beam	7 m (23 ft 0 in)
Draft	4.07 m (13 ft 4 in)
Installed power	4,200 bhp (3,100 kW) (diesel) 1,200 hp (890 kW) (electric motor)
Propulsion	Diesel-electric 1 × diesel engine 1 × electric motor
Speed	19.75 knots (36.58 km/h; 22.73 mph) surfaced 8 knots (15 km/h; 9.2 mph) submerged
Range	5,000 nmi (9,300 km; 5,800 mi) at 16 knots (30 km/h; 18 mph) surfaced 45 nmi (83 km; 52 mi) at 5 knots (9.3 km/h; 5.8 mph) submerged
Test depth	80 m (260 ft)
Crew	61
Armament	4 × bow 533 mm (21 in) torpedo tubes 1 × 76.2 mm (3.00 in) L/40 anti-aircraft gun 2 × single 25 mm (1.0 in) AA guns

Ro-40 was an Imperial Japanese Navy Kaichū type submarine of the K6 sub-class. Completed and commissioned in September 1943, she served in World War II and was sunk in February 1944 during her first war patrol.