HMS Dreadnought was a Royal Navy battleship, the design of which revolutionised naval power. The ship's entry into service in 1906 represented such an advance in naval technology that her name came to be associated with an entire generation of battleships, the dreadnoughts, as well as the class of ships named after her. Likewise, the generation of ships she made obsolete became known as pre-dreadnoughts. Admiral Sir John "Jacky" Fisher, First Sea Lord of the Board of Admiralty, is credited as the father of Dreadnought. Shortly after he assumed office in 1904, he ordered design studies for a battleship armed solely with guns and a speed of . He convened a Committee on Designs to evaluate the alternative designs and to assist in the detailed design work.
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 armament of smaller guns. She was also the first capital ship to be powered by steam turbines, making her the fastest battleship in the world at the time of her completion.Sturton, pp. 76–77 Her launch helped spark a naval arms race as navies around the world, particularly the Imperial German Navy, rushed to match it in the build-up to the First World War.
Although designed to engage enemy battleships, her only significant action was the ramming and sinking of German submarine ; thus she became the only battleship confirmed to have sunk a submarine. Dreadnought did not participate in the Battle of Jutland in 1916 as she was being refitted, nor did she participate in any of the other naval battles in World War I. In July 1916 she was relegated to coastal-defence duties in the English Channel, before rejoining the Grand Fleet in 1918. The ship was reduced to reserve in 1919 and sold for scrap two years later.
Genesis Background
Gunnery developments in the late 1890s and the early 1900s, led in the United Kingdom by Percy Scott and in the United States by William Sims, were already pushing expected battle ranges out to an unprecedented , a distance great enough to force gunners to wait for the shells to arrive before applying corrections for the next salvo. A related problem was that the shell splashes from the more numerous smaller weapons tended to obscure the splashes from the bigger guns. Either the smaller-calibre guns would have to hold their 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. Another problem was that longer-range torpedoes were expected soon to be in service and these would discourage ships from closing to ranges where the smaller guns' faster rate of fire would become preeminent. Keeping the range open generally negated the threat from torpedoes and further reinforced the need for heavy guns of a uniform calibre.Brown, David, pp. 180–182
In 1903, the Italian naval architect Vittorio Cuniberti first wrote about the concept of an all-big-gun battleship. When the Italian Navy did not pursue his ideas, Cuniberti wrote an article in Jane's Fighting Ships advocating his concept. He proposed an "ideal" future British battleship of , with a main battery of a dozen 12-inch guns in eight turrets, 12 inches of belt armour, and a speed of .Brown, David, p. 182
The Royal Navy, the Imperial Japanese Navy and the United States Navy all recognised these issues before 1905. The Royal Navy modified the design of the to include a secondary armament of guns that could fight at longer ranges than the guns on older ships, but a proposal to arm them solely with 12-inch guns was rejected.Parkes, p. 451This type of battleship with its secondary armament 9.2 inches or greater would become known retroactively as semi-dreadnoughts. See Sturton, p. 11 The was laid down as an all-big-gun battleship, five months before Dreadnought, but gun shortages allowed her to be equipped with only four of the twelve 12-inch guns that had been planned.Preston, p. 288 The Americans began design work on an all-big-gun battleship around the same time in 1904, but progress was leisurely and the two s were not ordered until March 1906, five months after Dreadnought was laid down, and the month after she was launched.Brown, David, p. 188
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 his yacht Turbinia with her speed of up to at Queen Victoria's Diamond Jubilee at Spithead in 1897. After further trials of two turbine-powered destroyers, and , coupled with the positive experiences of several small passenger ships with turbines, Dreadnought was ordered with turbines.Brown, David, pp. 183–184
The Battle of the Yellow Sea and Battle of Tsushima were analysed by Fisher's Committee, with Captain William Pakenham's statement that "12-inch gunfire" by both sides demonstrated hitting power and accuracy, whilst 10-inch shells passed unnoticed. Admiral Fisher wanted his board to confirm, refine and implement his ideas of a warship that had both the speed of 21 knots and 12-inch guns, pointing out that at the Battle of Tsushima, the Japanese ships commanded by Admiral Togo had been able to "cross the T" of the Russian ships due to speed.Massie, pp. 470–471, 474 The long-range ()Forczyk, p. 50 engagement during the Battle of the Yellow Sea, in particular, although never experienced by any navy prior to the battle, seemed to confirm what the Royal Navy already believed.Brown, David, p. 175
Development
Admiral Fisher proposed several designs for battleships with a uniform armament in the early 1900s, and he gathered an unofficial group of advisors to assist him in deciding on the ideal characteristics in early 1904. After he was appointed First Sea Lord on 20 October 1904, he pushed through the Board of Admiralty a decision to arm the next battleship with 12 inch guns and that it would have a speed no less than 21 knots. In January 1905, he convened a "Committee on Designs", including many members of his informal group, to evaluate the various design proposals and to assist in the detailed design process. While nominally independent it served to deflect criticism of Fisher and the Board of Admiralty as it had no ability to consider options other than those already decided upon by the Admiralty. Fisher appointed all of the members of the committee and he was President of the .Brown, David, pp. 186, 189–190
The committee decided on the layout of the main armament, rejecting any superfiring arrangements because of concerns about the effects of muzzle blast on the open sighting hoods on the turret roof below, and on 18 January 1905 chose turbine propulsion over reciprocating engines to save in total displacement. Before disbanding on 22 February, it decided on a number of other issues, including the number of shafts (up to six were considered), the size of the anti-torpedo boat armament,Roberts, pp. 12, 25 and most importantly, to add longitudinal bulkheads to protect the magazines and shell rooms from underwater explosions. This was deemed necessary after the was thought to have survived a Japanese torpedo hit during the Russo–Japanese War by virtue of her heavy internal bulkhead. To avoid increasing the displacement of the ship, the thickness of her waterline belt was reduced by .Brown, David, pp. 186, 190
The Committee reported their findings in March 1905. It was decided due to the experimental nature of the design to delay placing orders for any other ships until Dreadnought and her trials had been completed. Once the design had been finalised the hull form was designed and tested at the Admiralty's experimental ship tank at Gosport. Seven iterations were required before the final hull form was selected. Once the design was finalized, a team of three assistant constructors and 13 draughtsmen produced detailed drawings.Brown, Paul, p. 24 To assist in speeding up the ship's construction, the internal hull structure was simplified as much as possible and an attempt was made to standardize on a limited number of standard plates, which varied only in their thickness.Roberts, p. 13
Description Overview
Dreadnought was significantly larger than the two ships of the Lord Nelson class, which were under construction at the same time. She had an overall length of , a beam of , and a draught of at deep load. She displaced at normal load and at deep load, almost more than the earlier ships.Burt, p. 29 She had a metacentric height of at deep load and a complete double bottom.Roberts, pp. 14, 86–87
Officers were customarily housed aft, but Dreadnought reversed the old arrangement, so that the officers were closer to their action stations. This was very unpopular with the officers, not least because they were now berthed near the noisy auxiliary machinery while the turbines made the rear of the ship much quieter than they had been in earlier steamships. This arrangement lasted among the British dreadnoughts until the of 1910. The crew numbered 700 officers and ratings in 1907, but increased to 810 in 1916.
Propulsion Vickers, Sons & Maxim was the prime contractor for the ship's machinery, but as they had no large turbine experience, they sourced some from Parsons. Dreadnought was the first battleship to use turbines in place of the older reciprocating triple-expansion steam engines.Burt, p. 33 She had two paired sets of direct-drive turbines, each of which drove two diameter, three-bladed propellers usingJohnson & Buxton, p. 167 steam provided by 18 Babcock & Wilcox boilers that had a working pressure of . The turbines, rated at , were intended to give a maximum speed of 21 knots; the ship reached from during her sea trials on 9 October 1906.Roberts, pp. 15–16, 24, 26
+General arrangement of port engine room 1 – outer shaft; 2 – exhaust trunk from high pressure (HP) astern turbine for low pressure (LP) astern turbine; 3 – HP astern turbine; 4 – dummy piston; 5 – rotor shaft bearings; 6 – HP ahead turbine; 7 – inner shaft; 8 – main steam to HP ahead turbine; 9 – thrust block (outer); 10 – main steam to HP astern turbine; 11 – main steam from boiler room; 12 – astern manoeuvring valve; 13 – ahead manoeuvring valve; 14 – cruising manoeuvring valve; 15 – main steam to cruising turbine; 16 – main condenser; 17 – exhaust to the condenser; 18 – LP astern turbine; 19 – LP ahead turbine; 20 – exhaust trunk from HP for LP ahead turbine; 21 – exhaust trunk from cruising to HP ahead turbine; 22 – cruising turbine; 23 – thrust block (inner)
Dreadnought carried of coal, and an additional of fuel oil that was to be sprayed on the coal to increase its burn rate. At full capacity, she could steam for at a speed of .Roberts, p. 25
Armament
Dreadnoughts main armament consisted of ten 45-calibre BL 12-inch Mark X guns in five twin Mark BVIII gun turrets. The forward turret ('A') and two aft turrets ('X' and 'Y') were located along the centreline of the ship. Two wing turrets ('P' and 'Q') were located port and starboard of the forward superstructure respectively. Dreadnought could deliver a broadside of eight guns between 60° before the beam and 50° abaft the beam. Beyond these limits she could fire six guns aft, and four forward. On bearings 1° ahead or astern she could fire six guns, although she would have inflicted blast damage on the superstructure.Roberts, p. 28
The guns could be depressed to −3° and elevated to +13.5°. They fired projectiles at a muzzle velocity of , giving a maximum range of with armour-piercing (AP) 2 crh shells. Using the more aerodynamic, but slightly heavier, 4 crh AP shells extended the range to . The rate of fire of these guns was about two rounds per minute.Friedman, pp. 59, 61 The ships carried 80 rounds per gun.