Category:Heavy Crusers

At the end of the 19th century, cruisers were classified as First, Second or Third Class depending on their capabilities. First class Cruisers were typically armoured cruisers, hard to distinguish from a small pre-dreadnought battleship. The lighter, cheaper and faster Second and Third Class cruisers tended to have a protective armour deck, rather than armoured hulls, and hence were known as protected cruisers. In the first decade of the 20th century, the First Class Armoured Cruiser metamorphosed into the battlecruiser, and increased markedly in size and cost. At the same time, the Third Class Cruiser started to carry thin steel armour on the outside of its hull and became known as the light cruiser. The wide gap between the massive battlecruiser of perhaps 20,000 tons and 305 mm (12-inch) guns and the small light cruiser of up to 5,000 tons and 100 mm (4-in) or 155 mm (6-inch) guns naturally left scope for an intermediate type.

The first such design was the British 'Atlantic cruiser' proposal of 1912, which proposed a long-range cruiser of about 8,000 tons displacement with 190 mm (7.5-inch) guns. This was a response to a rumour that Germany was building cruisers to attack merchant shipping in the Atlantic with 170mm guns. The German raiders proved to be fictional and the 'Atlantic cruisers' were never built. However, in 1915 the requirement for long-range trade-protection cruisers resurfaced and resulted in the Hawkins class, which carried a 190 mm (7.5-inch) battery and had a displacement just under 10,000 tons.

It is important to note that the old armoured cruiser was not a close ancestor of these heavy cruiser models, even though the name sometimes suggests this. By 1905 the armoured cruiser had grown in size and power to be very close to the pre-dreadnought battleships of the day, with a displacement of around 15,000 tons: considerably larger than the 10,000 tons of the heavy cruiser. This trend resulted in the battlecruiser, which was initially conceived as an armoured cruiser on the same scale as the dreadnought battleship. By 1915, both battleships and battlecruisers had grown markedly; HMS Hood, for instance, designed at around that time, displaced 45,000 tons. The great gap between heavy cruisers and the capital ships of the same generation meant that, unlike the armoured cruiser, the heavy cruiser could not be expected to serve as a junior battleship.

There were also important technical differences between the heavy cruiser and the armoured cruiser which reflected the generational gap between them. Heavy cruisers, like all contemporary ships, were powered by steam turbine engines and were capable of far faster speeds than armoured cruisers had ever been. While the main armament of a heavy cruiser was smaller than the typical 233 mm (9.2-inch) guns of an armoured cruiser, the greater number of guns on the heavy cruiser and the introduction of fire control in the 1920s and 30s meant that the heavy cruiser was far more powerful.