Specification

Displacement: 12,400 tons standard Dimensions: length 203.9 m (669 ft); beam 20.2 m (66 ft 3 in); draught 5.8 m ( 19 ft)

Propulsion: geared turbines delivering 150, 000 shp ( 111855 kW) to four shafts

Armour: belt 100 mm (3.9 in); deck 35 mm ( 1.5 in); turrets 25 mm ( 1 in) Armament: 10 203-mm (8-in), eight 12'1-mm (5-in) DP and eight 25-mm AA guns, plus 12 610-mm (24-in) torpedo tubes

Aircraft: three floatplanes Complement: 850

Unlike her earlier naval model, the UK, Japan took to the 203-mm (8-in) cruiser enthusiastically, her only light cruisers being her 140-mm (5.5-in) gunned scouts such as the 'Sendai' class. But because of the restrictions of the 1930. London Treaty, however, four large 155-mm (6.1-in) gunned ships were built as the 'Mogami' class, this in turn stimulating the Americans to build the 'Brooklyn class, each class having a 15-tun main battery. To achieve the high designed speed of 3~ kts, the Japanese ships were very slender and proved to be dangerously vulnerable. They were, therefore, bulged externally in 193~. Less than two years later, all treaties having lapsed, they were again~ modified, their triple 155-mm (6.1-in) turrets being exchanged for

twin 203-mm (8-in) turrets and the bulge being increased in size. Their speed was now barely 34 kts, the same as that of the 'Brooklyn class but with 50 per cent extra power.

During World War II the class formed the coherent '7th Cruiser Squadron under the redoubtable Rear Admiral Kurita, and was continuously active. The Mogami, in company with the Mikuma, was instrumental in the destruction of the USS Houston and HMAS Perth after the Java Sea battle. Later, as part of the diversionary force involved in the Midway action, the two

cruisers collided heavily before being attacked by carrier aircraft; the Mikuma was sunk but Mogami, with 300 dead, survived to fight another day.

In November 1943 the Mogami, together with a large force of the Japanese fleet, was caught unawares by air attack at Rabaul. Hit heavily, blazing and down by the bows from flooded magazines, she again just made it. She then survived the Battle of the Philippine Sea only to meet her end at the night action in the Surigao Strait. Battered by gunfire, she collided with the Nachi but, typically, went in again. Shattered but afloat, she was attacked next day by aircraft. Her surviving crew removed, she was then sunk by a Japanese torpedo. The other two units were also lost in the war.