Ha-3 class submarine

Japanese submarine Ha-3, in August 1911
Class overview
Builders:	Vickers, Barrow-in-Furness, UK
Operators:	Imperial Japanese Navy
Preceded by:	Ha-1 class submarine
Succeeded by:	Ha-7 class submarine
In commission:	1911–1929
Completed:	3
Retired:	3
General characteristics
Type:	Submarine
Displacement:	291 long tons (296 t) surfaced 326 long tons (331 t) submerged
Length:	43.3 m (142 ft)
Beam:	4.14 m (13.6 ft)
Draft:	3.43 m (11.3 ft)
Installed power:	600 hp (450 kW) (gasoline engines) 300 hp (220 kW) (electric motors)
Propulsion:	Gasoline engines Electric motors 1 shaft
Speed:	12 knots (22 km/h; 14 mph) surfaced 7 knots (13 km/h; 8.1 mph) submerged
Range:	660 nm @ 12 knots (surfaced) 60 nm @ 4 knots (submerged)
Test depth:	30.5 metres (100 ft)
Complement:	26 officers and enlisted
Armament:	2 × 18 in (460 mm) bow torpedo tubes (4 × torpedoes) 1 × machine gun

The Ha-3 class submarine (波三型潜水艦, Ha-san-gata sensuikan) was an early class of submarines of the Imperial Japanese Navy.

Along with placing orders with Vickers at Barrow-in-Furness in the UK for two British C class submarines, which were commissioned into the Imperial Japanese Navy as the Ha-1 class, the Japanese government ordered another three vessels, which were received as knock-down kits. These kits were assembled at the Kure Naval Arsenal.

Physically almost identical to the Ha-1 class, the three vessels assembled in Japan incorporated a number of improvements, including extended bow for improved seaworthiness, improved rudder for surface handling, and an increase in the size of the bridge and conning tower.