Japanese submarine I-123

History
Imperial Japanese Navy
Name	Submarine No. 50
Builder	Kawasaki Corporation, Kobe, Japan
Laid down	12 June 1925
Launched	19 March 1927
Renamed	I-23 on 19 March 1927
Completed	28 April 1928
Commissioned	28 April 1928
Decommissioned	25 May or 25 November 1935 (see text)
Recommissioned	26 December 1935
Renamed	I-123 on 17 June 1938
Decommissioned	1 April 1939
Recommissioned	1 May 1940
Fate	Sunk 29 August 1942
Stricken	5 October 1942
General characteristics
Class and type	I-121-class submarine
Displacement	1,142 long tons (1,160 t) surfaced 1,768 long tons (1,796 t) submerged
Length	85.20 m (279 ft 6 in) overall
Beam	7.52 m (24 ft 8 in)
Draft	4.42 m (14 ft 6 in)
Propulsion	2 × Rauschenbach Mk.1 diesels 2,400 bhp surfaced 1,100 shp submerged 2 shafts
Speed	14.9 knots (27.6 km/h; 17.1 mph) surfaced 6.5 knots (12.0 km/h; 7.5 mph) submerged
Range	10,500 nmi (19,400 km; 12,100 mi) at 8 knots (15 km/h; 9.2 mph) surfaced 40 nmi (74 km; 46 mi) at 4.5 knots (8.3 km/h; 5.2 mph) submerged
Test depth	75 m (246 ft) (as built) 55 m (180 ft) (from 1936)
Complement	80
Armament	2 × 533 mm (21 in) torpedo tubes 12 × 6th Year Type torpedoes 1 × 14 cm/40 11th Year Type naval gun[1] 42 × naval mines

I-123, originally named Submarine No. 50 then renamed I-23 from before her construction began until June 1938, was an I-121-class submarine of the Imperial Japanese Navy that served during the Second Sino-Japanese War and World War II. During the latter conflict, she conducted operations in support of the Japanese invasion of the Philippines, the Battle of Midway, the Guadalcanal campaign, and the Battle of the Eastern Solomons. She was sunk in 1942.

After she was renumbered I-123 in 1938, the designation I-23 was reassigned to a later submarine which also served during World War II.