Izumo in 1905
|Builders:||Armstrong Whitworth, United Kingdom|
|Operators:||Imperial Japanese Navy|
|Preceded by:||Asama-class cruiser|
|Succeeded by:||Japanese cruiser Yakumo|
|Displacement:||9,750 long tons (9,906 t)|
|Length:||132.28 m (434 ft 0 in) w/l|
|Beam:||20.94 m (68 ft 8 in)|
|Draught:||7.37 m (24 ft 2 in)|
|Propulsion:||2 shaft VTE
14,500 ihp (10,800 kW)
1412 tons coal
|Speed:||20.75 knots (24 mph; 38 km/h)|
|Range:||7,000 nmi (13,000 km) at 10 kn (12 mph; 19 km/h)|
|Armament:||• 4 × 20.3 cm/45 Type 41 naval guns
• 14 × QF 6 inch /40 naval guns
• 12 × QF 12 pounder 12 cwt naval guns
• 8 × QF 3 pounder Hotchkiss
• 4 × 457 mm (18.0 in) torpedo tubes
|Armour:||Main belt: 88–175 mm (3.5–6.9 in)
Upper belt: 125 mm (4.9 in)
Deck: 67 mm (2.6 in)
Turret, casemate: 150 mm (5.9 in)
Conning tower: 356 mm (14 in)
|Aircraft carried:||1 × Nakajima E4N floatplane (from 1934; Izumo only)|
The Izumo-class Armored Cruisers (出雲型装甲巡洋艦 Izumo-gata sōkōjun'yōkan?) was an early class of two armored cruisers operated by the Imperial Japanese Navy. They participated in numerous actions during the Russo-Japanese War and World War I. Partly disarmed and de-rated in the 1930s, they were restored to combat status for World War II, but due to their obsolescence, were used for training within the confines of the Seto Inland Sea during that conflict.
The Izumo-class armored cruiser were the second pair of six cruisers ordered from overseas shipyards after the First Sino-Japanese War as part of the "Six-Six Program" (six battleships-six cruisers) intended form the backbone of the Imperial Japanese Navy. Construction of the Izumo-class ships was awarded to the British shipbuilder Armstrong Whitworth of Elswick, the same shipyards who had built the previous two Asama-class cruisers.  The Japanese navy specification for the Izumo-class was almost identical to that of the Asama-class; however, minor differences internally and a major external difference (i.e. three smokestacks instead of two) mean that the second pair of cruisers in the construction program are regarded as a separate class of ship.
The hull of the Izumo-class cruiser was a typical flush deck with high freeboard to improve seaworthiness. As with Asama, the Izumo-class used a steel housing divided into 166 waterproof compartments, a low forecastle, and two masts.The design still came with a ram attached to the bow. The main armament was 20.3 cm/45 Type 41 naval guns mounted in gun turrets in the bow and stern. These guns could rotate 150 degrees to either side and could elevate to 30 degrees, firing at a rate of two rounds per minute. Secondary armament consisted of fourteen Elswick QF 6 inch /40 naval gun quick-firing guns, with a range of 9,140 meters and a firing rate of five to seven shots per minute. The Izumo-class was also equipped with twelve QF 12 pounder 12 cwt naval guns, seven QF 3 pounder Hotchkiss guns and five 457 mm torpedo tubes. Armor plating was the newly developed Krupp armor instead of the Harvey armor used by preceding classes.
Improvements in steam engine design allowed her triple expansion reciprocating engine to be built with 24 Belleville boilers instead of the 12 locomotive-style boilers in Asama. This resulted in a weight savings of over 300 tons. The class had a rated speed of 21.5 knots (39.8 km/h) and a range of 7,000 nautical miles (13,000 km) at 10 knots (19 km/h) based on bunkerage of 1409 tons of coal. 
Ships in class
Ordered in 1897, launched on 19 September 1898, and completed 25 September 1900, Izumo participated in the Russo-Japanese War, World War I and World War II. Between both World Wars, it served as a training ship for long distance oceanic navigation and officer cadet training for the Imperial Japanese Navy Academy. She is generally credited with sinking HMS Peterel (1927) at Shanghai, the first Royal Navy vessel sunk in the Pacific War. She was sunk at dock in an American air attack on Kure 24 July 1945.
Ordered in 1897, launched 29 March 1900, and completed 18 March 1901, Iwate participated in the Russo-Japanese War, World War I and World War II. It between wars, she served as a training ship for long distance oceanic navigation and officer cadet training for the Imperial Japanese Navy Academy. It was sunk in an American air attack on Kure 26 July 1945.
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|Wikimedia Commons has media related to Izumo class armored cruisers.|
- Nishida, Hiroshi. "Materials of IJN". Imperial Japanese Navy.
- Brooke, Warships for Export page 58-60
- Chesneau, Conway's All the World's Fighting Ships, 1860–1905, p. 225.