Fast battleship

A fast battleship was a battleship which in concept emphasised speed without undue compromise of either armor or armament. Most of the early World War I-era dreadnought battleships were typically built with low design speeds, so the term "fast battleship" is applied to a design which is considerably faster. The extra speed of a fast battleship was normally required to allow the vessel to carry out additional roles besides taking part in the line of battle, such as escorting aircraft carriers.

A fast battleship was distinguished from a battlecruiser in that it would have been expected to be able to engage hostile battleships in sustained combat on at least equal terms. The requirement to deliver increased speed without compromising fighting ability or protection was the principal challenge of fast battleship design. While increasing length-to-beam ratio was the most direct method of attaining a higher speed, this meant a bigger ship that was considerably more costly and/or could exceed the naval treaty tonnage limits (where these applied, such as the Washington Naval Treaty shaping naval fleet composition after World War I). Technological advancements such as propulsion improvements and light, high-strength armor plating were required in order to make fast battleships feasible.

Unlike battlecruiser, which became official Royal Navy usage in 1911, the term fast battleship was essentially an informal one. The warships of the Queen Elizabeth class were collectively termed the Fast Division when operating with the Grand Fleet. Otherwise, fast battleships were not distinguished from conventional battleships in official documentation; nor were they recognised as a distinctive category in contemporary ship lists or treaties. There is no separate code for fast battleships in the U.S. Navy's hull classification system, all battleships, fast or slow, being rated as "BB".

Between the origins of the armoured battleship with the French Gloire and the Royal Navy's Warrior at the start of the 1860s, and the genesis of the Royal Navy's Queen Elizabeth class in 1911, several battleship classes appeared which set new standards of speed. Warrior, at over 14 knots (26 km/h) under steam, was the fastest warship of her day as well as the most powerful. With the increasing weight of guns and armour, this speed was not exceeded until Monarch (1868) achieved 15 knots (28 km/h) under steam. The Italian Italia of 1880 was a radical design, with a speed of 18 knots (33 km/h), heavy guns and no belt armour; this speed was not matched until the 1890s, when higher speeds came to be associated with second-class designs such as the Renown of 1895 (18 knots) and the Swiftsure and Triumph of 1903 (20 knots). In these late pre-dreadnought designs, the high speed may have been intended to compensate for their lesser staying power, allowing them to evade a more powerful opponent when necessary.

From about 1900, interest in the possibility of a major increase in the speed of Royal Navy battleships was provoked by Sir John ("Jackie") Fisher, Commander-in-Chief of the Mediterranean Fleet. The Senior Officer's War Course of January 1902 was asked to investigate whether a ship with lighter armour and quick-firing medium guns (6 to 10 in, 150 to 250 mm calibre), with a 4-knot (7 km/h) advantage in speed, would obtain any tactical advantage over a conventional battleship. It was concluded that "gun power was more important than speed, provided both sides were determined to fight"; although the faster fleet would be able to choose the range at which it fought, it would be outmatched at any range. It was argued that, provided that the fighting was at long range, an attempt by the faster fleet to obtain a concentration of fire by "crossing the T" could be frustrated by a turn-away, leading to the slower fleet "turning inside the circle of the faster fleet at a radius proportional to the difference in speed" (Figure 1). War games conducted by the General Board of the U.S. Navy in 1903 and 1904 came to very similar conclusions.

Fisher appears to have been unimpressed by these demonstrations and continued to press for radical increases in the speed of battleships. His ideas ultimately came to at least partial fruition in the Dreadnought of 1906; like Warrior before her, Dreadnought was the fastest as well as the most powerful battleship in the world.

Dreadnought was the first major warship powered by turbines. She also included other features indicating an increased emphasis on speed:

In the decade following the construction of Dreadnought, the Royal Navy's lead in capital ship speed eroded as rival navies responded with their own turbine-powered "dreadnoughts". Meanwhile, in the UK, Fisher continued to press for still higher speeds, but the alarming cost of the new battleships and battlecruisers provoked increasing resistance, both within the Admiralty and from the Liberal government that took office in 1906. As a result, many potentially significant fast battleship designs failed to achieve fruition.