Duncan class battleships

The Duncan class of battleships were the last of a series of battleship designs that can be traced back to the Royal Sovereign class ships of 1891-1892. These were the classic pre-dreadnought battleships, armed with four main guns (13.5in on the Royal Sovereign class and 12in on all later ships), supported by a battery of 6in guns. The Duncans would be followed by the King Edward VII class, which carried an intermediate battery of 9.2in guns, part of the trend that would lead to the all-big-gun HMS Dreadnought.

The Duncan class ships were similar in size to the previous London class ships, but carried less armour and more powerful engines, giving them an increased top speed of 19kts and a sea speed of 18kts. This meant that they were able to keep up a high speed for much longer than the heavier London class ships. They are a good example of the Admiralty’s habit of building ships in response to the rumoured specifications of a potential opponent's ships, in this case fast battleships believed to be under construction in Russia.

Plans of Duncan Class Battleships
Plans of
Duncan Class

The Duncans were powered by four cylinder triple expansion engines. Standard three cylinder triple expansion engines passed their steam through a series of increasingly large cylinders, starting with the smallest high pressure cylinder, then an intermediate size and pressure cylinder and finally a large low pressure cylinder. This was designed to extract as much power as possible from the available steam.

One limit with this type of engine was the size of that last low pressure cylinder. A four cylinder engine solved that problem by having two smaller than usual low pressure cylinders, each getting half of the steam. The two triple expansion engines in the Duncans provided 18,000ihp, an increase of 3,000ihp over the London class ships. 

The four cylinder triple expansion engine would be used on the last two classes of pre-dreadnought first class battleships, the King Edward VII class of 1903-1904 and the Lord Nelson class of 1906 before being superseded by the turbine engine.

At the start of the First World War the five “Duncans” were part of the Second Fleet. They were not on a war footing, but had an “Active Service Crew”, containing all of the specialist officers and three fifths of the rest of the crew. The remaining men were onshore undergoing training, but could reach the ships quickly if needed. They were intended to form part of the Channel Fleet, so didn’t need to be ready for the instant dash to Scapa Flow required of the First Fleet.

At the start of August the “Duncans” were to form part of the 6th Battle Squadron of the Channel Fleet. However, they had always been seen as possible reinforcements for the Grand Fleet. On 5 August Jellicoe was asked if he wanted them, and he said yes. HMSs Russell, Albemarle and Exmouth were dispatched immediately, as their crews had been completed, with the other two ships following when ready. The 6th Battle Squadron was suppressed and its ships moved to other squadrons.

Once at Scapa the “Duncans” formed part of the 3rd Battle Squadron, with the eight King Edward VII battleships. In mid-October they were used to form part of the Northern Patrol, operating north of the Shetlands while the 10th Cruiser Squadron was detached to take part in the operations to protect the Canadian troop convoy.

On 2 November it was believed that the German Navy was about to try something in the southern part of the North Sea or the Channel. Accordingly the entire 3rd Battle Squadron was sent south to join Admiral Burney at Portland. The planned German activity turned out to be an attack on Yarmouth and Gorleston on the east coast, launched on 3 November. When news of the raid reached Jellicoe the 3rd Battle Squadron was off the north west coast of Ireland. There was no way it could reach the south coast in time to take part in the action, so Jellicoe ordered it to return to Scapa in case the German raiders moved north. Later on the same day that danger had passed, and the squadron turned south yet again, this time actually reaching Portland.

The eight King Edward VII class ships did not stay in the south for long. In mid-November Jellicoe requested the return of the entire squadron. The five “Duncans” were split off to form a new 6th Battle Squadron, a special service squadron under Rear-Admiral Stuart Nicholson, and the King Edwards were sent back to Scapa.

The new 6th Battle Squadron had been created to attack the German U-boat bases on the channel coast. They were initially based at Dover, before a storm swept away the anti-submarine boom early in November. They then returned to Portland, before returning to Dover again on 13 November, this time to guard against a German invasion of south east England. 

The big attack on the U-boat bases never really came off. On 23 November HMS Exmouth and HMS Russell did bombard Zeebrugge, but it was becoming clear that the risk of loosing a battleship in these operations outweighed the benefits to be gained in all but the most desperate situations.

During 1915 the squadron was broken up. Albemarle remained in home waters, while the other four ships all served in the Mediterranean, where Cornwallis and Exmouth played a major role in the Dardanelles operations. Russell and Cornwallis were both lost in the Mediterranean, in 1916 and 1917 respectively. 

Displacement (loaded)


Top Speed


Armour – deck


 - belt


 - bulkheads


 - barbettes


 - gun houses


 - casemates


 - conning tower





Four 12in guns
Twelve 6in quick firing guns
Ten 12pdr quick firing guns
Six 3pdr guns
Four 18in torpedo tubes

Crew complement






Ships in class

HMS Albemarle
HMS Cornwallis
HMS Duncan
HMS Exmouth
HMS Russell

British Battleships 1889-1904 New Revised Edition, R A Burt. Magnificent study of the Royal Navy's pre-dreadnought battleships, amongst the most powerful ships in the world when built, but seen as obsolete by the outbreak of war in 1914. Traces the development of the 'classic' pre-dreadnought design and the slow increase in the power of the secondary armament, leading up to the all-big gun ships that followed. [read full review]
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How to cite this article: Rickard, J (5 November 2007), Duncan class battleships , http://www.historyofwar.org/articles/weapons_duncan_class_battleships.html

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