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HMS Dreadnought


HMS Dreadnaught was the only member of the Dreadnaught class of battleships.

The Royal Navy named seven ships Dreadnought as shown in the table below.

DateBrief History
1573The first Dreadnaught was a 41-gun ship scrapped in 1646
1691The second Dreadnought was a 60-gun 4th rate ship scrapped in 1748.
1742The third Dreadnought was also a 60-gun 4th rate ship scrapped in 1784.
1801The fourth Dreadnought was a 98-gun 2nd rate ship that was converted to a hospital ship in 1827 and scrapped in 1857.
1879The fifth Dreadnought was a turret ironclad battleship built at Pembroke Dockyard, Wales and scrapped in 1908.
1906The sixth ship was the Dreadnought covered on this page.
1960The seventh Dreadnought was the UK's first Nuclear powered submarine so the name Dreadnought was used for two epoch making vessels.

Prior to HMS Dreadnought, most if not all battleships carried four large guns, usually 12 inch, in two twin turrets, one forward and one aft, a battery of secondary guns which over the years crept up from 6 inches to 9.2 inches (in the RN) and numerous smaller guns to defend against attack by smaller ships.

This status quo had existed for a considerable time but on the 26-27 May 1905 a battle between the Russian and Japanese navies in the Tsushima Straits in which the Japanese ships trounced the opposition at 7,000 yards - at the time a long range - using mainly the main battery guns, proved that it was better to hit hard with fewer larger guns than to smother a target with lots of smaller weapons. The lessons of this battle were not lost on either the Japanese, American or British navies. The Royal Navy was not innovative; to be innovative meant making all your existing ships obsolete. This could be costly if you had a vast number of ships, so the RN tended to be conservative and respond in kind to innovations in other fleets.

Jackie Fisher

One man was set to change this. In October 1904 Admiral Sir John (Jackie) Fisher assumed the position of First Sea Lord. Fisher had many new ideas and set up a committee to implement them. One of his ideas was very radical indeed. It called for a battleship carrying no less than twelve 12" guns in six twin turrets, three forwards and three aft all in super-firing positions. However traditionalists had their say and the idea of super-firing was discounted; guns had open sighting hoods in these days and the effects of muzzle blast were an unknown factor.

Image 1 shows shows Admiral of the Fleet John Arbuthnot "Jackie" Fisher, 1st Baron Fisher, GCB, OM, GCVO (25 January 1841 – 10 July 1920) [2]

HMS Dreadnought

Another of Fisher's ideas was to build not battleships but battle-cruisers; all big gun ships with high speed and light armour. Thankfully the traditionalists in the Admiralty stayed with the battleship plan.

So Dreadnought was born, she encompassed three new ideas – the all big gun armament, steam turbine propulsion and the elimination of longitudinal passageways below the main deck – all previous designs had had numerous water-tight doors in the bulkheads below the upper-deck to permit fore and aft movement with the attendant risk of flooding.

Basic Data

BuildersRoyal Navy Dockyards
Country UK
Displacement (Std)18,110 tons
Displacement (Full load)21,45
Length527 ft
Breadth82 ft
Draught31 ft
EnginesTwo Parsons direct drive steam turbines
Engine buildersVickers
Boilers18 Babcock coal-fired boilers operating at 230psi
Power24,712 SHP
PropulsionFour Screws
Speed21 knots
ComplementApprox. 700-775

Additional Construction Information

Engines and Propulsion

HMS Dreadnaught had quadruple propellers driven by Parsons direct drive steam turbines built by Vickers. The turbines consisted of a high pressure ahead and astern turbine on the outboard shafts, and a low pressure ahead and astern on the two inboard shafts. The inboard shafts also incorporated an ahead cruising turbine for fuel economy.

The turbines developed a total of 23,000 SHP and gave 21 knots. On trials she attained 24,712 SHP which gave 21.05 knots. Steam at 250 PSI was generated by 18 Babcock & Wilcox coal fired boilers which were arranged in three groups. Coal consumption was 340 tons per day at full speed which was quite good. At 13 knots (4,000 HP) consumption was not very good at 160 tons per day. Apart from power, speed and weight saving, the turbines were a lot smoother running with less vibration allowing better gun laying. Coal capacity was 2,900 tons with 1,120 tons of oil giving a radius of 5,000 miles at 19 knots but only increasing to 6,600 miles at 10 knots so she was not an economical slow speed steamer.


Superfiring is a gun turret arrangement by which two turrets are positioned in a row, one above (super) and behind the other.

Superfiring is illustrated in Image 6 which shows the forward turrets of the Emperor of India (Iron Duke class). A pair of turrets, in this case 13.5", are arranged in super-firing positions. The arrow indicates the open sighting hoods on 'A' turret and the possibility of these being affected by the muzzle blast of 'B' turret above. This would only be a problem with the guns trained fore and aft - which is not a desired firing solution as only these two turrets would bear on the target.

The final design for Dreadnought was for ten 12" guns in five twin turrets, one on the foc’sle deck and four on the upper deck with no super-firing. Although this satisfied the traditionalists, it meant that only eight of these guns could engage on a broadside as four guns were mounted in two wing turrets restricted to firing on their own side of the ship. This allowed an eight-gun broadside and was equalled by the American South Carolina class which had eight 12" guns in four super-firing turrets. This effectively meant that the ship was carrying 500 tons of ballast in an unused turret when this weight could have been used as extra armour or fuel if super-firing had been adopted, quite apart from the space wasted on a fifth magazine. This concentration of guns meant that six could fire ahead whilst eight could fire astern but over very limited arcs of fire.

Image 2 shows shows the forward turrets of the Emperor of India (Iron Duke class) [3]

HMS Dreadnought

Building Costs

One of the things that Fisher had to prove was that the cost of the new ship would not be prohibitive. Due to careful management, the cost of Dreadnought was kept to £1,785,683. This compared very favourably with the cost of the King Edward the VII at £1,472,075 bearing in mind that the earlier ship only mounted 4 12" guns, so pound for gun the Dreadnought was far better value.

Speed of Construction

In order to steal a march on other navies who had also come up with their own ideas of an "all big gun" battleship, speed was of the essence. The United states had the same ideas as Fisher but did not lay down their South Carolina class ships, South Carolina BB26 and Michigan BB27, until December 1906 with a very leisurely build rate. Commissioning was not until 1910 and Japan laid their Satsuma class (Satsuma and Aki) in March 1905 which were also commissioned in 1910/11.

Dreadnought was laid down by Portsmouth navy yard on the 2 October 1905, she was launched on the 10 February 1906 and completed in December 1906, just over a year after being laid down - although to be fair, a good degree of steel cutting and preparation had taken place prior to laying down in order to speed up the process. In fact construction had started even before a building way was available. On her completion, Dreadnought made all preceding warships obsolete overnight, including those of the Royal Navy, but Fisher's gamble was that Britain could out-build every other nation and construct a new navy of Dreadnought-type battleships thus maintaining her "two-navy" superiority. In this policy the Royal Navy's strength had to equal that of her two strongest opponents.

One of the reasons for building Dreadnought so fast was to demonstrate to the world that whatever anyone did, Britain would equal it and build it faster so that Britain would maintain her superiority, and the speed of build really did surprise other nations. However this theory did not work and in particular Germany was embarked on an arms race of Dreadnought building. Britain herself built six virtual repeats of Dreadnought between 1906 and 1911 these were the St Vincent class (St Vincent, Vanguard and Collingwood) Neptune class (single ship) and Colossus class (Collossus and Hercules) all the ships were very similar except that the Neptune and Collossus class had super-firing turrets aft, they also had 4" secondary batteries. Dreadnought and her follow on sisters lead was very short lived, the Orion appeared in 1912, with her sister ships, Conqueror, Thunderer and Monarch. These four ships totally outclassed the Dreadnought, not just because of their new 13.5" guns, but because they used super-firing for the four forward and aft turrets with a fifth 'Q' mounted amidships so all ten guns could now fire in a broadside. It might have been interesting that had Britain not been first in building Dreadnought, all modern battleships might have been called Carolinas or perhaps Satsumas - not quite the same ring.

Career Highlights

2 October 1905Keel laid down
10 February 1906Launched by King Edward VII
2 December 1906Commissioned
9 May 1921Sold to TW Wards
2 January 1922Arrived at Inverkeithing for breaking up

Image 3 shows HMS Dreadnought being launched on 10 February 1906. [1]

HMS Dreadnought

Image 4 shows HMS Dreadnought immediately after the launch. Areas in her hull side are recessed for later installation of armour plating.[1]

HMS Dreadnought

Image 5 shows HMS Dreadnought being towed to her fitting-out berth after launching. [1]

HMS Dreadnought

Image 6 shows HMS Dreadnought - probably on her trials. If you look closely you will notice a single twelve pounder gun on top of 'A' turret were there should be a pair indicating that not all work on her has been completed.

The booms at regular intervals down her sides are the supports for the anti-torpedo nets, these would be swung out with the ship at anchor and a heavy steel mesh net suspended from them, this was meant to stop a torpedo from hitting the ship, in fact torpedoes had been fitted with net cutters and the nets were quite useless and there was the added risk in battle of them being damaged, trailing in the water and fouling the ships propellers or rudder. [1]

HMS Dreadnought


Main Battery

Dreadnaught had ten 12" C45 Mk10 guns in five twin turrets. These guns were designed in 1904 for the two pre-dreadnought Lord Nelson class battleships, but to speed up construction of the Dreadnought they were assigned to her. In one of life’s ironies this delayed the construction of the Lord Nelson and Agamemnon until 1908 – 2 years after the Dreadnought, which was the ship that made them obsolete. Construction of the guns was of wire winding on a steel inner tube and covered with a steel jacket, bore length was 45 calibres or 540 inches and fitted with an improved mechanical type breech. Each gun weighed approximately 57 tons with the two gun turret weighing a total of 450-500 tons. Although of a calibre favoured by the Admiralty, these guns were not a good weapon at long range as the shell tended to wobble in flight giving poor accuracy. The guns had a range of 16,500 yards at an elevation of 13.5 degrees and fired a shell weighing 850 to 859lbs using a propellant charge of 258lbs. of Cordite MD45 (MD standing for Cordite Modified - now obsolescent and comprised 65% guncotton, 30% nitroglycerine and 5% Vaseline. The number indicates this is a rod shaped propellant ie it is in long rods not granular).

The charges were in four silk bags; the silk was a special type called Shallon - much coarser than normal silk, this ensured that it burnt completely in the barrel so as to leave no residue that might ignite a following charge. The shell life of the guns was reasonable at 220 rounds per gun (RPG) with on board stowage being 800 rounds or 80 RPG. Rate of firing was two rounds per minute on gun-layers tests, but in battle it was nearer one round per minute. Penetration was given as 10.5" of armour plate at a range of 10,000 yards. The forward and aft turrets could fire through an arc of 0 to 150 degrees either side with the mid-ships turrets firing 60 degrees either side of the beam. Training was quite slow at 4 degrees per second.

Dreadnought was one of the earliest ships to be fitted with a means of electronically transmitting range, order and deflection information to the turrets; this replaced the highly unsatisfactory voice pipes previously used. The equipment comprised the latest Bar & Stroud range finder using a nine foot base length (previous lengths were 4.5 feet). This data was fed into a Dumaresq clock which was basically a mechanical computer which worked out rates of change and off-sets to be applied to the guns for a moving target. The data was then sent to the transmitting station located within the armoured section of the ship, which transmitted the information to the turrets. This is a far cry from director firing but still a great step forwards "in gun" control. In 1909 Dreadnought was fitted with a gun director however it was removed before it was ever tested and she did not use director firing until 1914. One of the big failings on Dreadnought was the positioning of the foremast behind the forward funnel. Smoke and gasses seriously affected the spotting top and thus affected the fighting efficiency of the main guns. On the plus side Dreadnought was said to be a very steady gun platform which reading between the lines meant she was very wet and uncomfortable for her crew.

Image 7 is a sketch of the location of guns on HMS Dreadnought [4]

HMS Dreadnought

Note by Steve Woodward: The above sketch of the upper and foc'sle decks of Dreadnought shows the location of the 12 pounder guns with a 'T' symbol - the capital letters give the main turret designations. There is still some doubt as to the exact locations of the 12-pounder guns; the only certain positions are the pairs on top of the five main turrets. I apologise for the poor quality of my artwork - technical drawing was not on the curriculum at my school.

Secondary Armament

The secondary battery consisted of twenty-four Mk1 QF 12 Pounders all in single mounts. The name of the gun stems from the size of shell fired which was actually 12.5lbs; the gun size was in reality a 3" C50. The mount weighing 18 CWT and they fired fixed ammunition i.e. the 2.75lb propellant charge was in a brass cartridge case fixed to the projectile thus giving the gun the Quick firing (QF) notation. Rate of fire for a trained crew being in the order of 15 RPM. 300 rounds per gun were carried and the barrel life was around 1,200 rounds. This weapon was designed in the very late 1800s as an anti-torpedo boat weapon and should not be confused with the 12pndr Mk1 C45 AA weapon, which was designed in 1910. The weapon on Dreadnought was more primitive, and it was also woefully inadequate. A three inch gun would not be enough to stop a determined torpedo boat; also the layout of the secondary battery was very poor being close to the main battery. In fact ten of the guns were on top of the main turrets making them unusable when the main battery was in action. The reasoning behind this was that the ship would not be engaging small craft when in a fleet action with the main battery. This was a very dangerous assumption as at Jutland both sides 'sent in the destroyers' during the fleet action.

Torpedo Armament

Dreadnought was also fitted with five submerged type 18 inch torpedo tubes - two on either beam and one aft. The Whitehead torpedoes had a range of 800 yards at just over 26 knots and were powered by three cylinder compressed air engines and carried a 118lb wet gun cotton warhead.

Armour Protection

The vertical armour plating on Dreadnought was called KC or Krupp Cemented armour. Krupp plates are made of nickel-chrome steel and undergo a special heat treatment during manufacture. Cementation is a process in which the prepared steel plate is placed in a special furnace and the face to be cemented is in contact with a special type of carbon, over a very long period of time. The temperature is gradually raised and then lowered after cementation has taken place. The plate is then reheated and immersed quickly in an oil bath, the plate reheated to a lower temperature and immersed in a water bath. Although called Krupp Armour, the process for the Dreadnought's armour was done in the UK. The Deck armour plating was KNC - Krupp Non Cemented armour.

Plate thicknesses were:

This was modest but compared reasonably well with pre-Dreadnought armour schemes. One of the reasons for not having heavier armour was the desired need for greater subdivision and the threat of underwater damage caused by torpedoes. Dreadnought had partial fore and aft bulkheads protecting the magazine areas - these bulkheads were often referred to as screen bulkheads or simply screens. Although an improvement on earlier designs, Dreadnought remained poorly protected against underwater damage.

Operational History

On completion, Dreadnought assumed the role of flagship of the 4th Battle Squadron of the Grand Fleet. On the outbreak of WW1, she handed the flag over to Benbow in December 1914 and on the 18th March 1915 she rammed and sank the U-Boat U-29 whilst on patrol in the North Sea. She remains to this day the only battleship to sink a submarine by direct action.

Dreadnought was in refit at Portsmouth in early 1916 so she missed the battle of Jutland on the 31st May. At the end of the refit in June 1916 she joined the 3rd Battle Squadron at Sheerness and narrowly missed ramming a second u-boat. At the end of June she assumed the role of Flagship in the third BS.

In March 1918 she rejoined 4th Battle Squadron but this was short lived and in February 1919 she went into reserve at Rosyth. She was now in rather poor condition due to the endless patrols she made during the war and of course less maintenance than she should have had.

In March 1920 she was approved for scrapping and put up for sale, and was sold to TW Wards on the 9 May 1921 for the Sum of £44,000. She was then towed to Inverkeithing for breaking up, arriving on 2 January 1922. So ended the battleship built to beat all others of her kind without ever having actually fought one.

Post Jutland, Bellerophon carried out regular patrols of the North Sea with other ships of the Grand Fleet. As the relief Flagship of the 4th Battle Squadron, her Admirals were RAs Roger Keyes and Douglas Nicholson. She had a quiet existence with no events of note and, unlike her sisters Temeraire and Superb, was not sent to the Mediterranean.

Post-war, now superseded by the super-Dreadnoughts with 13.5 inch guns, she was placed in reserve in 1919 and converted to a Gunnery Training School; Bellerophon lasted just over two years in this role. A victim of the 1920 Washington arms reduction Treaty, she was sold to the breakers in November 1921 and broken up in 1923.

Image Credits

  1. Expired Crown Copyright photographs by courtesy of the US Department of the Navy - Naval Historical Center
  2. By courtesy of Wikipedia.
  3. Unknown provenance
  4. Sketch by Steve Woodward