Dreadnought battleship

The sixth HMS Dreadnought of the Royal Navy was a revolutionary battleship which entered service in 1906. So advanced was Dreadnought that her name became a generic term for modern battleships, whilst the ships she made obsolete became known as "pre-dreadnoughts". Her introduction helped spark off a major naval arms race as navies around the world rushed to match her, particularly the German navy in the build up to the First World War.[1] Dreadnought was the first battleship of her era to have a uniform main battery, rather than having a few large guns complemented by a heavy secondary battery of somewhat smaller guns. She was also the first major warship to be powered by steam turbines, making her the fastest battleship in the world at the time of her completion.

Genesis
Battleships of the era typically carried four large guns mounted fore and aft in twin turrets, with a number of smaller-calibre guns ranged along the sides of the ship, often in armoured turrets or casemates. This arrangement had several disadvantages: the lateral guns could only fire at targets on their side, while rotating turrets mounted on the centreline could fire to either side. Water entering through the many gunports was a hazard in heavy seas. Furthermore, each calibre of gun had different ballistic properties, which greatly complicated gunnery, especially when watching for splashes. Either the smaller-calibre guns would have to hold fire to wait for the slower-firing heavies, losing the advantage of their faster rate of fire, or it would be uncertain whether a splash was due to a heavy or a light gun, making ranging and aiming unreliable.

The invention by Charles Algernon Parsons of the steam turbine in 1884 led to a significant increase in the speed of ships with his dramatic unauthorised demonstration of Turbinia with its speed of up to 34 knots (63 km/h) at the Spithead Navy Review in 1897. After further trials and construction of two turbine powered destroyers, HMS Viper and HMS Cobra, the Admiralty confirmed in 1905 that future Royal Navy vessels were to be turbine powered.

"All-big-gun" concepts
The idea of "all-big-gun" warships, capable of firing powerful guns from a long distance seems to have emerged as the threat from torpedoes became more potent. The Italian naval architect Vittorio Cuniberti first articulated the concept of an all-big-gun battleship in 1903 (although British admiral Jackie Fisher claimed the idea had occurred to him by 1900). When the Italian Navy didn't pursue his ideas, Cuniberti wrote an article in Jane's propagating his concept. He proposed an "ideal" future British battleship of 17,000 tons, with a main battery of twelve 12 inch (30 cm) guns, 12 inch belt armour, and speed of 24 knots (44 km/h).

Japanese development (1904-1905)
The Russo-Japanese War (1904-1905) provided operational experience to validate the concept. The Russian Navy was decisively defeated during the naval battles of the Russo-Japanese War (1904–1905), especially at the Battle of Tsushima (May 1905), by the modern Imperial Japanese Navy, which was equipped with modern-era battleships, mostly of British design. The events of the battle confirmed to the world that only the biggest guns mattered in naval battles at that time. As secondary guns grew in size, spotting and discriminating between splashes of main and secondary guns became problematic. The Battle of Tsushima demonstrated that damage from the main guns was much greater than secondary guns. In addition, the battle demonstrated the practicality of gun battles beyond the range of secondary guns (12,000 yards / 11 km). The United States, Japan, and Britain all realised this and launched plans for all-big-gun ships. The Imperial Japanese Navy's Satsuma was the first battleship in the world to be designed (1904) and laid down (15 May 1905) as an all-big-gun battleship, five months before Dreadnought, although gun shortages only allowed her to be equipped with four of the twelve 12 inch (30 cm) guns that had been planned.

American development
Influenced by William S. Sims, Americans also worked on an all-big gun design around the same time as Dreadnought: USS South Carolina and USS Michigan were presented to Congress in 1904. The Americans moved slowly. The ships were not authorised until the spring of 1905 and not laid down until the autumn of 1906, after Dreadnought. The South Carolina class carried all of their main guns on the centreline, avoiding the wing turrets favoured by the British. Unlike Dreadnought, they used triple-expansion machinery, not the latest and much more powerful steam turbines developed on Tyneside, in England, by Charles Algernon Parsons a few years before.

British development
Britain, led by Admiral Sir John "Jackie" Fisher, who became First Sea Lord in 1904, took the lead. Fisher's "Committee of Designs" which he assembled in December 1904 consisted of the Director of Naval Construction and other senior figures. This generated the design for Dreadnought. In order to have the new ships which he desired, Fisher had to make them financially attractive as well - showing that they would cost less to build and run than the current battlefleet. Dreadnought was laid down and assembled with unparalleled speed in Portsmouth Royal Dockyard. She was laid down on 2 October 1905, and was completed just 14 months later in December 1906 (according to Conway's, a basin trial in October 1906 was treated "for publicity purposes ... as completion", thereby providing official sanction for the often-repeated claim that she was built in a year and a day ). Fisher had originally advocated a Royal Navy based around submarines and fast torpedo boats, and had subsequently tempered his revolutionary ideas with a vision of fast, all-big-gun battlecruisers, which would have the firepower and speed to engage battleships and cruisers, albeit with much less armour protection than the former. Fisher felt that speed was a better defence than armour. Although the battlecruiser concept would become popular in the run-up to World War I, Fisher was nonetheless forced by the Admiralty to create an all-big-gun battleship instead.

Technology
The concept was simple, and had been a consideration among naval planners for a few years. Dreadnought would use steam turbines in place of the older triple-expansion engines that had powered almost all previous ships, giving her a design speed of a steady 21 knots (39 km/h). This would allow her to outrun any existing battleship with comparable firepower, while she could outgun any faster vessel in keeping with Forrest's axiom. Submarines were largely ignored. Thus protected from smaller ships, lighter guns that would normally be placed along the sides of the ship to deal with them could be omitted. This left considerably more room for the largest guns, which were placed in turrets on the main deck.

Dreadnought mounted five two-gun turrets. Three turrets were located conventionally along the centreline of the ship, with one fore (A turret) and two aft (X & Y turret), the latter pair separated by the torpedo control tower located on a dwarf tripod mast. Two further (wing) turrets (P & Q turrets) were located either side of the bridge superstructure, each able to fire only towards its side. Arrangement of all the turrets along the ship's centreline was rejected in order to minimise the risk of blast damage to the closely-packed turrets, although this precaution was later found to be unnecessary. Dreadnought could deliver a broadside of eight guns, and fire eight guns abaft or six ahead, in each case only in a narrow range of angles; she could never fire all her ten 12 inch (30 cm) guns at one target. At the time of her design end-on fire was regarded, at the instigation of Jackie Fisher, as being of paramount importance over and above broadside fire. This design concept was perpetuated in the succeeding classes, and in the earlier battlecruiser classes.

Later British battleships, starting with the Superdreadnoughts of the Orion class, used a superimposed arrangement, with turrets arrayed in a stair-step arrangement on the centreline. Additional light guns were included for close-in defence but were not intended as offensive weapons.

The vessels which Dreadnought was expected to engage could only bring to bear four guns of similar size, plus shorter-range guns; Dreadnought would endeavour to engage within the range of her guns, but stay out of the range of smaller guns. giving her far more effective firepower than earlier battleships.

The use of a uniform main battery greatly simplified the task of adjusting fire in action. As all guns had the same ballistic characteristics the shells fell in a cluster whose size was determined by random variations and whose centre was subject to errors in aiming and other deterministic effects such as wind. If the shells were seen to splash beyond the target, the range was shortened, and viceversa; if the target was bracketed, the next volley used the same settings, adjusted for ship speeds and course changes. For a given powder load, range adjustments were made by small adjustments to elevation. This simplicity was not available if the guns are of different types and observers did not know which guns created which splashes.

Dreadnought was one of the first vessels of the Royal Navy to be fitted with instruments for electronically transmitting range, order and deflection information to the turrets, removing the reliance on voice-pipes which had been shown to be ineffective in combat. The fire-control equipment, consisting of the transmitting equipment and Vickers range clocks (a variable speed clock that predicted the changing range between two vessels), were located in the Transmitting Station (T/S in navy parlance) in the heart of the ship for protection.

The transmitting station was connected to the spotting top by a large diameter armoured voice-pipe where a dumaresq, a rate of change device, placed with a rangefinder - the initial range, spotting corrections and deflection being called down to the transmitting station. After she returned from her shakedown cruise Dreadnought was fitted with electrical means of transmitting information from the spotting top to the transmitting station. Her rangefinders by Barr and Stroud were of a new type, having a 9 foot base length as opposed to the standard 4½ foot base on almost every other naval vessel. This allowed for greater accuracy of determining the range at distance.

The director, a device invented by Admiral Percy Scott in conjunction with the armament firm of Vickers for transmitting the range and deflection to all turrets and then firing them simultaneously, was first installed on Dreadnought in 1909 but removed before being tested. It was not until the First World War that she would be fitted with the device again.

Another major innovation was the elimination of longitudinal passageways between compartments below the main deck level. While doors connecting compartments were always closed during combat, connected compartments had been found to be a cause of weakness following a collision during fleet exercises which resulted in the sinking of a battle cruiser.

Sailing ships were controlled from the aft part of the ship, and officers were customarily housed aft. Steam ships were controlled from the bridge, high and in the first quarter or third of the ship; Dreadnought reversed the old arrangement, housing officers in the forward part of the ship and enlisted men aft, so that both officers, and stokers and enginemen, were closer to their action stations.