Japanese Cruiser Izumo - Design

Design

The basic design for all cruisers in the "Six-Six Program" was the same, although each shipyard was relatively free in details. The design for Izumo was based on that of the Asama-class cruiser, except that 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. As with Asama, Izumo had a steel housing divided into 166 waterproof compartments, a low forecastle, and two masts. The prow was reinforced for ramming. However, her armor plating made use of the newly developed Krupp armor instead of the Harvey armor used by her predecessors.

The main armament of Izumo were two separate 20.3 cm/45 Type 41 naval guns in gun turrets in the bow and stern. The 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 firing rate of five to seven shots per minute. Izumo was also equipped with twelve QF 12 pounder 12 cwt naval guns, seven QF 3 pounder Hotchkiss guns and five 457 mm torpedo tubes.

Izumo was laid down on 14 May 1898, launched on 19 September 1899 and handed over to the Japanese on 25 September 1900. Externally, the main difference Izumo and her predecessors Asama and Tokiwa was the use of three smokestacks instead of two.