Nelson-class battleship

The Nelson class was a class of two battleships (HMS Nelson (28) and HMS Rodney (29)) of the British Royal Navy, built shortly after, and under the terms of, the Washington Naval Treaty of 1922. They were the only British battleships built between the (ordered in 1913) and the, ordered in 1936.

The ships were named after famous British admirals: George Brydges Rodney, 1st Baron Rodney of the Battle of Cape St. Vincent and Horatio Nelson, 1st Viscount Nelson of the Battles of the Nile and Trafalgar.

To comply with the limitations of the Washington treaty, these ships were of an unusual design with many novel features. They are often referred to as the first treaty battleships. The Nelsons were unique in British battleship construction, being the only ships to carry a main armament of nine 16 in guns. These were all carried forward.

Commissioned in 1927–29, the Nelsons served extensively in the Atlantic, Mediterranean, and Indian oceans during World War II. HMS Rodney (29) was made famous by her very important role in the sinking of the GERMAN BATTLESHIP Bismarck in May 1941. During that battle, Rodney's nine main guns were credited with an estimated 100 to 130 hits on the German battleship, so being largely responsible for the total disabling of Bismarcks four main gun-turrets and destruction of the superstructure, prior to her sinking.

Nelson participated in the bombardment of targets in northern France during and after the Normandy attack. In particular, during the Caen campaign she was credited with the destruction of a group of five Tiger tanks which ventured well into the red zone defined by the German command, which was located at the line of maximum range of the allied battleships (40 km. from the Coast)

The two ships of the class survived the war, but were scrapped in 1948–49 along with almost all other British battleships except HMS Vanguard (23).

History and design
The Battle of Jutland had shown the value of firepower and protection over speed and manoeuvrability.

The next generation of British warships incorporated this lesson. After the First World War, the Admiralty drew up plans for massive, heavily armoured battlecruisers and battleships, far larger and stronger than all previous vessels. The G3-class battlecruisers would carry 16 in guns, and the proposed N3-class battleships would carry nine 18 in guns, and would be the most powerful vessels afloat. The Royal Navy was planning to hold its superiority in the burgeoning arms race, despite the large warships planned in Japan and the United States.

Development was abruptly curtailed by the Washington Naval Treaty of 1922, which brought the arms race to a halt. The four battlecruisers that had been ordered were cancelled. Some of the material acquired would later be used in Nelson and Rodney. The Treaty limited all nations' battleships to 35,000 tons and 16-inch guns. The British had successfully ensured that the definition of maximum displacement – the "standard displacement" – excluded both fuel and boiler feed water. They had argued that having to protect the widespread British Empire meant their ships had to carry more of both and they should not be penalised compared to nations, such as Japan, France and Italy, that operated normally much closer to their home bases. As a result, water-filled internal anti-torpedo bulges could be incorporated, which did not contribute to the "dry" (standard) weights and therefore didn't exceed the treaty displacement limits.

The limits of the treaty inevitably led to compromises in the design of two new ships, and the resulting Nelson class sacrificed installed power (and hence speed) in order that they be well-armed and defended. They were often referred to as the "Cherry Tree" class, because they had been "cut down by Washington". The need to limit displacement resulted in a radical new warship design, drawing from the G3 and N3 designs. To reduce the weight of armour, the main gun turrets were mounted all forward, shortening the necessary armoured citadel length. The G3 and N3's had put two turrets forward of the bridge with the third between the bridge and the funnels and aft superstructure. However in the Nelsons, this was taken further and all three were in front of the bridge; with 'B' mount superfiring over 'A', with 'X' turret on the fo'c'sle deck behind 'B', and therefore unable to fire directly forward or aft. 'X' turret is sometimes referred to as 'C' turret and one alternative design had it superfiring over both 'A' & 'B' turrets. The secondary guns were placed in totally enclosed director-controlled turrets at the main deck level and were grouped aft – another innovative element taken from the G3 and N3 design.

The machinery was of necessity limited in weight, size and installed power, and there were only two shafts with quite large screws. All previous British battleships since HMS Dreadnought (1906) of 1906 had four screws as did all British battleship classes after Nelson. In order that flue gasses be kept clear of the superstructure, the boiler rooms were moved behind the engine rooms, exhausting into a single funnel. This orientation also reduced the overall length of the armoured citadel. As a countermeasure to the limited power, the hull was of a very efficient hydrodynamic form, to attain the best possible speed.

Armour
Armour weight was also reduced by using an internal, inclined armour belt sloped at 72 degrees vertically, 14" thick over the main magazines and control positions to 13" over the machinery and 6" gun magazines . The slope increased the relative thickness of the belt to a plunging projectile. Water filled compartments surrounded by air-filled torpedo bulges were fitted internally between the external hull of the ship which was not armoured. The outer hull plating was meant to initiate detonation of shells which would then explode outside the armour. The armour scheme was of the "all or nothing" principle; areas were either well protected, from the front of 'A' barbette rearwards to the after 6" turrets, or were not protected at all, disposing of the multiple intermediate thickness of armour seen in older designs. For the first time a British battleship had a single, 6.25" thick armoured deck to protect against plunging shells and aircraft-dropped bombs with 4.25 in armour over the stern, both on top of the 0.5 in (12.7 mm) deck plating. The main turrets had 16" NC armour on the faces, 11" on the sides, 7.25" on the roof and 9" on the rear with 15" around the barbettes. The secondary turrets however had only 1" NC all round.

Superstructure
The large superstructure which was octagonal in plan, was known to its crew as the "Octopoidal" and was sometimes referred to as "Queen Anne's Mansions", due to its similarity to Queen Anne's Mansions a 14-storey brick residential development of the that name, opposite St. James's Park underground railway station in London. The superstructure provided spacious, weatherproof working spaces for the navigating officers and any flag officers embarked. This innovative bridge design was subsequently copied by the French in the Dunkerque class battleships, as was the all-forward main armament orientation, features which were both repeated in the Richelieu class designs. Other than an emergency conning tower at its base, and the trunking for the main gun directors mounted on top, the superstructure was lightly armoured against splinters only, to save weight. Other weight-saving measures included the use of light materials such as aluminium for fittings, and fir instead of teak for deck planking, although in practice teak decks were fitted in the late 1920s, following concerns that the ships could not fire a full broadside without causing structural damage to the decks.

The Nelson class was a revolutionary but compromised design, and unsurprisingly there were shortcomings. The rearward location of the superstructure caused manoeuvrability problems in high winds, especially when steaming at low speeds, where the superstructure acted somewhat like a mizzen sail permanently set, causing the ships to "weathervane" but according to Capt. T.H. Binney "if this is kept in mind, no real difficulties should be encountered in any circumstances". This was potentially a problem in crowded harbours, and made the ships somewhat difficult to dock and embark although this issue never led to a major incident. T.H. Binney, Nelson's captain in the late twenties and later admiral in the Royal Navy also stated "In the early stages of the ship's first commission, there was a general misconception that the Nelson class were unhandy and difficult to manoeuvre. Both my predecessor and myself (sic), however, very soon discovered that this opinion was entirely fallacious! In calm weather, the ship's manoeuvring capabilities are in no way inferior, and in many ways superior to those of Queen Elizabeth or Revenge." They could also be awkward to manoeuver when moving astern. This was attributed to the ships having a single centre rudder which was out the propeller race of the twin screws. At sea, however, they were reported to handle well, with a comparatively small Tactical Diameter (turning circle) particularly when turning into the wind, according to Lt.Cmdr. Galfrey Gatacre RAN (later Rear Admiral), who served in 1941-2 as the Navigator for both the Nelson and subsequently the Rodney. He reported no difficulty in navigating either ship through the boom gates at Scapa Flow. The Nelson and the Rodney were the only battleships to never have bumped the boom gate vessel as they passed through Hoxa Sound.

Armament
Their main armament of nine 16 in guns were mounted in triple turrets, the only RN battleships designed in this manner. The guns themselves deviated from standard British designs. Where previous RN weapons fired heavy shells at a moderate velocity, the Nelson's weapons followed the German practice of a lighter shell at a higher velocity. This change in Director of Naval Ordnance policy was due to British testing of surrendered German equipment post World War I, although much later subsequent testing proved contradictory. Two different rifling rates were tried, and for sometime there was a mixture of barrel types in different turrets, even sometimes within the same turret. The guns suffered considerable barrel wear and had a fairly large dispersion pattern, due mainly to the different riflings that each barrel had as they were refurbished over their lifespan. To compensate for barrel wear muzzle velocities were reduced and a heavier (longer) shell was tried to offset this, but the cost of producing new shells, and modifying shell handling and storage equipment came at a time when RN funding had been heavily reduced. Nevertheless these weapons were not generally considered by the RN to be as successful as the previous BL 15 inch Mark I but were considered more successful than the BL 14 inch Mark I fitted to the subsequent King George V class battleships. The need to reduce displacement led to the use of triple mount turrets which had early problems with the ammunition handling and loading machinery. Also the heavier weight of the triple Vs a twin turret meant increased stresses on the roller bearings when training the turrets. This was solved by the incorporation of both vertical as well as horizontal roller bearings. The triple mount turret proved itself, when in October 1929, one turret crew with two years experience loaded and fired 33 rounds without mishap. The incorporation of many safety features achieved with lighter materials meant that the complex but relatively fragile equipment had to be serviced regularly over the ships' lifetime. These ships were fitted with the HACS AA fire control system and the Admiralty Fire Control Table Mk I for surface fire control of the main armament.

Finally, the blast of the guns disrupted some officers on the bridge to such an extent that the guns of 'X' turret were usually prohibited from firing abaft of the beam at high elevations of 40 degrees during peacetime practice firing. Fitting tempered glass in the bridge windows was tried, but gun blast shattered some of them and filled the bridge with flying debris. A great deal of effort was expended in correcting this problem, and fitting of protective ledges below the bridge windows proved successful. Blast was also a problem elsewhere; D.K. Brown tells of a test firing that was suspended when DNC observer, H.S. Pengelly, who was beneath the foredeck, reported a bright red flash after firing. This was later discovered to be caused by concussion of the observers' eyeballs.

Critical Assessment
Because of their unusual silhouette, HMS Nelson and her sister Rodney were sarcastically nicknamed Nelsol and Rodnol by the Royal Navy ratings who never served in these ships – their manoeuvrability issues and single-funnelled silhouettes reminded Navy men of oil tankers, and a series of fleet oilers that had been built during the First World War that bore names ending in "ol". There was a long-standing rumour that the ships could not fire a full broadside without risk of structural damage. This was disproved in Rodney's action with the German battleship Bismarck, where upwards of 40 broadsides (380shells) were fired without major structural damage except to deck planking and upper deck fittings, although damage to sickbay fittings, partition bulkheads, toilet bowls and plumbing in the forecastle was extensive. Rodney also held the distinction of being the only battleship to have ever successfully torpedoed another battleship when one of its twelve 24" torpedoes hit Bismarck amidships. Despite the derisive criticism directed at this class of battleship by some of the media and 'old salts' of the navy upon their debut, well respected Naval Historian, Antony Preston declares that they were 'Soundly conceived ships reflecting all the hard-won experience of World War One' and 'they proved to be very well-protected and well-designed ships'. It is significant that in his 2002 book "The World's Worst Warships" he makes no criticism of the Nelsons whatsoever, yet lists both s and "Panzerschiff" (pocket battleships) amongst the worst designs.

Service
By the end of the war, the two ships had seen hard use without any significant refit or repair and were worn out, especially their machinery. They were both scrapped in 1948 not long after the s and s, in the midst of great public-spending cuts, but nonetheless causing much public outcry.