I-121-Class (Type KD3a)
Interwar Fleet Boats - I-121-class were early Japanese fleet submarines. 3 boats commissioned 1927. Medium-sized (1,390/1,768 tons), six torpedo tubes + 12 torpedoes. 17.3 knots surfaced. Kaidai (fleet submarine) type - designed for fleet scouting and attack. Two lost in combat (I-121, I-122). One (I-123) became training sub, scrapped 1945. Represented 1920s Japanese submarine development - learning fleet submarine operations before larger designs.
Specifications
- Displacement (std)
- 1142 t
- Displacement (full)
- 1768 submerged t
- Length
- 279.5 ft
- Beam
- 24.7 ft
- Crew
- 60
- Ships built
- 3
- Commissioned
- 1927
- Decommissioned
- 1942-1945 (all sunk or scrapped)
Performance
- Top speed
- 14.9 kn
- Range
- 10000 nm at 10 knots surfaced
Armament
- Secondary guns
- None
- Torpedoes
- 6× 533mm (21-inch) - 4 bow, 2 stern
Armor & Systems
- Belt
- None
In-Game
- Tier
- T4
- Game power
- 77.85
- Research cost
- 27,403
- Credit cost
- 54,495
Notable
- Early interwar Japanese fleet submarines (1927)
- Kaidai (fleet submarine) type development
- WWI influence on design
- 2 lost in combat, 1 scrapped before war
- I-123 only survivor (scrapped 1945)
- Represented 1920s submarine technology