Nelson class battleship
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The Nelson class were battleships of the British Royal Navy built shortly following the Washington Naval Treaty in 1922. They were the first British battleships since the Revenge class of 1913, and the last until the King George V class. Because of the limitations of the treaty the structure of the ships had to be revised, which resulted in unusual design considerations.
Two ships of the class were produced, both named after famous British admirals: HMS Rodney and HMS Nelson .
History and design
The Battle of Jutland had shown the value of firepower and protection over speed and maneuverability. Admiral Fisher's dictum that "speed is armor" had been tested in battle, and had been decisively disproved. Thickness of armor and weight of shell were now seen as the keys to naval victory.
The next generation of British warships were to incorporate this lesson. After the War the Admiralty drew up plans for massive, heavily armored battlecruisers and battleships, far larger and stronger than all previous vessels. They would carry 16 and 18 in (406 and 457 mm) guns and would be the most powerful vessels afloat.
However, development was abruptly halted by the signature of the Washington Naval Treaty in 1922.
The Treaty limit of 35,000 tons and 16 in (406 mm) guns killed the projected super-warships, and the Royal Navy was forced to scale down its designs. The result of this compromise was the Nelson Class of battleships. These were well-armored and defended (nine 16 in (406 mm) guns in three turrets), but light and small enough to conform to the Treaty terms. (Navy men referred to this as the "Cherry Tree Class", because it had been "cut down by Washington").
The need to increase firepower and armor, while keeping weight low, resulted in a radical new warship design:
In order to reduce weight of armor, all the primary gun turrets were mounted on the foredeck. They could then be served by a single magazine, instead of the two necessitated by traditional designs, thus shortening the necessary armored length. The secondary guns were all located near the stern for the same reason. The engines and superstructure were also placed aft in order to balance the heavy weight of the primary armament.
Armor weight was also saved by using an internal, inclined armor belt. The external hull of the ship was unarmored. Inclined armor increases the effective thickness of the belt, and its internal disposition was intended to provide a low-resistance path to vent torpedo explosions out of the ship (this feature was unsuccessful). Also for the first time, a British dreadnought was given thick decks to protect against plunging shells and aircraft-dropped bombs.
This new and unusual design had several serious flaws.
Despite the rear location of the superstructure, the center of gravity of the ships was still too far forward. This caused maneuverability problems in high wind: the superstructure acted as a sail, causing the ships to "weathervane" when steaming at low speeds. This was a particularly dangerous problem in crowded harbors, and the ships were notoriously difficult to dock and embark.
The inclined armor disposition considerably increased the danger of shells diving under the armor belt. In a seaway, with wave motion along the side of the ship, with the ship rolling, perhaps with a list caused by damage, the ship would have been at risk of shells passing almost unhindered into the vitals of the ship. In publicly-released information, the Admiralty always showed the inclined armor to be much deeper than was actually the case.
These ships were very different from the rest of the British battle fleet. They were the first RN dreadnoughts to carry their secondary armament in turret which greatly improved serviceability in heavy seas. Their main armament of 16"/45 guns were mounted in triple turrets, the only RN dreadnoughts to do so. The guns themselves where a step away from standard RN design. Where previous RN weapons fired heavy shell at a low velocity, the Nelson class followed the German practice of a lighter shell at a higher velocity. This change in policy was due to British post-war tests, although subsequent testing proved contradictory and these weapons were never considered to be as successful as the previous 15"/42. The guns suffered considerable barrel wear and had a large dispersion pattern. As a result their muzzle velocities were lowered which reduced their penetrative power. A heavier shell was needed but the cost of producing new shells and modifying shell handling and storage equipment had come at time when RN funding had been heavily reduced and so they had to make do.
Finally, the blast of the guns firing disrupted officers on the bridge to such an extent that the guns were usually prohibited from firing abaft of the beam. A great deal of effort was expended in correcting this problem, and no solution was ever found. They even placed tempered glass in the bridge window holes, but firing the guns shattered them and filled the bridge with flying debris.
The ships
In consequence of this, HMS Nelson and her sister Rodney were sarcastically nicknamed Nelsol and Rodnol by the Royal Navy - their maneuverability problems and silhouettes reminded Navy men of oil tankers, not battleships. (Royal Navy oilers were always given names ending in "ol".)
The closeness of the primary turrets to each other was also a danger to the structural integrity of the ships. The crews were warned to never fire all the 16 in (406 mm) guns at the same time, because this would damage the deck - clearly, a serious handicap on a fighting ship.
Another complication was the size of the forward gun deck. This area had to be kept clear of obstructions since any structures located there would be destroyed by the blast of the guns. However, this left a very large area of the deck where anti-aircraft guns could not be sited. The problem was partially solved by mounting AA guns on top of the turrets, though air defense remained a serious weakness with these vessels throughout their careers.
In theory the "all-forward" design reduced the danger of an enemy "crossing the T" of the ship, since all the main guns could be brought to bear on forward targets. However, this advantage was offset by the awkward location of the third ("X") turret. For structural reasons it was mounted lower on deck than the second ("B"), which severely limited its forward field of fire. This was bad enough, but "X" could also not fire in the aft quarters without damaging the superstructure. (The bridge was a particularly unpleasant place to be when firing on distant stern targets.)
When the Washington Treaty lapsed in 1936 the Royal Navy abandoned the "all-forward" arrangement and returned with relief to traditional designs.
Despite these difficulties both Nelson and Rodney had successful careers during World War II, the latter vessel helping to sink KMS Bismarck in 1941 (although the guncrews ignored engineers' instructions during the battle, and inflicted more damage on their own ship than Bismarck did.)
General Characteristics
- Displacement: 34,000 tons, 38,000 full load
- Length: 710 ft (216 m) overall
- Beam: 106 ft (32 m)
- Draft: 30 feet (9.1 m)
- Complement: 1,500
- Armament: nine 16 in (406 mm) guns; twelve 6 in (152 mm) guns; six 4.7 (119 mm) AA guns; eight 4 (102 mm) guns; eight 2 pounder (907 g) pom-poms; 32-48 1.57 (40 mm) pom-poms; two 24.5 in (622 mm) torpedo tubes
- Speed: 23.8 knots
- Propulsion: Two Brown Curtis geared turbines, two screws
- Armour: Belt 14 in (356 mm); 6 in (152 mm) deck; 16 (406 mm) turret front, 9 in (229 mm) sides; 15 in (381 mm) barbettes
| Nelson-class battleship |
| Nelson | Rodney |
| List of battleships of the Royal Navy |