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The King George V-class battleships (KGV) were the last British battleship design completed for use during World War II, and only one further battleship was completed after the war. Five ships of the class were commissioned: King George V (1940), Prince of Wales (1941), Duke of York (1941), Howe (1942), and Anson (1942).

The Washington Naval Treaty limiting both the quantity, size (in tonnage), and armament of post First World War battleship construction had been extended by the First London Naval Treaty, but the treaty was due to expire in 1936. With increased tension between the various major naval nations, it was expected by planners that the treaty might not be renewed and the King George V-class was designed with this loss of restriction in mind.

All five ships served in the Second World War. Prince of Wales was the only one lost when she, along with the battlecruiser HMS Repulse (1916) were sunk by Japanese air attack near Singapore. The surviving ships were broken up in the late 1950s.

Development
The King George V class was the outcome of a design process dating from 1928. Under the terms of the Washington Naval Treaty of 1922, a 'holiday' from building capital ships was in force until 1931. The battleship element of the British Navy consisted of only those battleships retained after the end of the First World War and the two new but slow Nelson-class battleships. In 1928 the Royal Navy commenced discussion of the staff requirements for the ships it expected to begin in 1931.

In the event, the First London Naval Treaty of 1930 extended the 'building holiday' to 1937. Planning recommenced in 1935, drawing on previous design work. The new class would be built up to the Treaty maximum displacement of 35,000 tons. Alternatives with 16-inch, 15-inch, and 14-inch main guns were considered, and it was determined the 15-inch armament would give the best balance. Most designs were intended to make about 27 knots, and it was reasoned the likely decisive range in a battle would be 12,000 to 16,000 yards. Armour and torpedo protection would form a much greater proportion of the design than previous British battleships.

In October 1935, the decision was made to use 14-inch guns. At the time, Britain was negotiating a continuation of the Naval Treaties with the other parties of the First London Treaty. The British favoured a reduction in the maximum calibre of battleship gun to 14-inch, and in early October learned the United States would support this position if the Japanese could also be persuaded to do so. As the guns needed to be ordered by the end of the year, the Admiralty decided to use a 14-inch gun on the King George V-class. The Second London Naval Treaty, a result of the Second London Naval Conference begun in December 1935, was signed in March 1936 by the US, France and the UK confirming 14 inch guns as the treaty limit; however Japan left the conference in January and Italy refused to sign.

Machinery
The King George Vs were the first British battleships to alternate engine rooms and boilers in the machinery spaces. This reduced the likelihood of a single hit causing the loss of all power. The machinery was arranged in four engine (turbine) rooms and four boiler rooms, with the 8 machinery compartments being alternated in pairs of engine or boiler rooms, forward to aft in the citadel. Each pair of boiler rooms formed a unit with a pair of engine rooms. Nominal full power was 110,000 shp at 230 rpm with 400 psi steam at 700 f. The machinery was designed to operate at an overload power of 125,000 shp and Prince of Wales' "...main machinery steamed at overload powers of 128,000 to 134,000 shaft horsepower with no difficulties." during the hunt for the Bismarck. The Admiralty boilers operated very efficiently and similar boilers of nearly identical power, fitted to HMS Warspite during her 1937 rebuild, achieved a full power specific fuel consumption of .748lb per shp on trials which compared favourably with contemporary battleships. However, after 1942 the Royal Navy was forced to use fuel oils with considerably higher viscosity and greater seawater content than these boilers could efficiently use. The poor quality of the oil fuel combined with the seawater contamination to reduce the efficiency of the steam power plant and increased the maintenance required. By 1944 the specific full power fuel consumption had increased to .8lb per shp and boiler maintenance was becoming increasingly difficult. The Admiralty had been aware of this problem and were designing new types of oil sprayers and burners that could burn the available fuel oil much more efficiently, and sometime after 1944, Duke of York and Anson were fitted with new higher pressure oil sprayers and burners that restored the boilers to full efficiency. These same oil sprayers and burners were used on HMS Vanguard along with other detail improvements so that Vanguard achieved a full power specific fuel consumption of .63 lb per shp while using the same steam pressures and temperatures as used on the KGV class.

Armour


The armour protection of the King George V-class battleships was designed after consideration of the Royal Navy's experience of the First World War and upon full scale testing between the wars. Magazine protection was given priority through the provision of a thick belt and deck armour and by placing the magazines at the lowest levels of the ship.

The horizontal protection over the magazines consisted of three layers with a total thickness of 9.13 inches; the weather deck consisted of 1.25 inches of D steel, the main armoured deck was 5.88 inches thick over a .5 inch D steel deck, and above the shell rooms there was another 1.5 inch splinter deck. The powder magazines were located below the shell rooms for added protection, a practise that was begun with the Nelson class battleships. The weatherdeck thickness was the same over the machinery spaces, but there the main armoured deck was reduced to 4.88 inches over a .5 inch D steel deck. The main armoured deck was continued forward of the forward armoured bulkhead and gradually reduced from full thickness to 2.5 inches, while aft of the after magazines an armoured turtle deck covered the steering gear with 4.5–5 inches of armour whilst also providing protection along the waterline.

The main armour belt was 23.5 ft high and covered the hull side from the main armoured deck to finish 15 ft below the deep waterline. Post-First World War studies had indicated that it was possible for delayed-action AP shells to dive under a shallow belt and penetrate into vital areas of the ship and therefore the main belt was made to extend as far below the waterline as possible. Along the ship, the belt started just forward of the forward turret and finished just aft of the aft turret. The belt was at its thickest above, and at, the waterline. Along the magazines, the belt was 15 inches thick (381 mm); over the machinery spaces, the belt was 14 inches (356 mm). The lower section of belt tapered to a thickness of between 4.5 in and 5.5 in. Armour protection was even better than the thickness of armour would indicate due to the improved qualities of the cemented armour which provided excellent resistance. The armoured belt, together with armoured bulkheads fore and aft and the armoured main deck, formed an "armoured citadel" protecting magazines and machinery. The armoured bulkhead was 12 in (305 mm) thick forward and 10 in (254 mm) thick at the after end of the citadel The main armoured belt extended forward and aft of the main armoured bulkheads with reduced height to protect the waterline and gradually reduced in thickness from 13 to 5.5 inches. Immune zone calculations vary wide from source to source.

The main gun turrets were relatively lightly protected in comparison to contemporary battleships. Maximum turret and barbette armour was reduced to 12.75 inches in this class from the 16 inches of the Nelson class. The turret faces had 12.75 in (324 mm) of armour at the front; 8.84 in sides (at the gun chamber); 6.86 inches (284–174 mm) on the sides and rear; the roof plate was 5.88 in (149 mm) thick. The main armament barbettes were of varying thickness: 12.75 in (324 mm) thick on the sides, 11.76 in (298 mm) forward and 10.82 in (275 mm) aft of the turret. To some extent the higher quality of the armour minimized the loss of protection and the turret's flat face improved ballistic resistance at long ranges, while the low profile of the turret minimized target area at closer ranges. However the reduction in turret and barbette armour was a design trade off in favour of the thickest possible protection for the magazines. The extensive anti-flash protection in the turrets and barbettes was designed to ensure that the magazines would remain safe even if the turrets and/or barbettes were penetrated. The secondary gun mounts, casements and handling rooms received only light plating of 0.98 in (25 mm) to protect against splinters.

Unlike contemporary foreign battleships and the preceding Nelson class battleships, the KGV class had comparatively light conning tower protection with 2.94 inches (75 mm) inches sides, 3.94 in (100 mm) forward and aft and a 1.47 in (38 mm) roof plate. The RN's analysis of the First World War revealed that command personnel were unlikely to use an armoured conning tower, preferring the superior visibility of unarmoured bridge positions Stability and weight considerations clearly played an important part in the British decision to limit superstructure armour. The conning tower armour was sufficient to protect against smaller ship guns and shell fragments.

Underwater protection
The hull below the waterline, along the main armour belt, formed the Side Protection System (SPS). It was subdivided into series of longitudinal compartments in a void-liquid-void layout; the outer and inner were filled with air, and the middle compartment with liquid (fuel or water). The outer hull plating in the region of the SPS was made as thin as possible to minimize splinter damage in the event of a torpedo hit. The outer compartment of the SPS was normally an empty or void space (containing only air) and this allowed the initial explosion from a torpedo to expand while minimizing damage to the ship. The centre compartment was filled with oil or seawater and this spread the pressure pulse over a larger area while the liquid contained any metal splinters that were created from the torpedo explosion. The inboard compartment was another void space and served to contain any liquid leaking from the liquid layer and any remaining pressure pulse from the torpedo explosion. Inboard of the final void space was an armoured bulkhead which varied in thickness from 1.5 in (37 mm) over the machinery spaces to 1.75 inch (44 mm) abreast of the magazines. This bulkhead formed the "holding bulkhead" and it was designed to resist the residual blast effects from the torpedo hit. If this final inner bulkhead was penetrated a further set of subdivided compartments would contain any leaks; inboard of the holding bulkhead the ship was highly subdivided into small compartments containing auxiliary machinery spaces. The SPS void-liquid-void layer was generally about 13 feet wide, and the auxiliary machinery spaces added approximately another 8 feet of space from the outer hull plating to the major machinery spaces. The only exception to this was abreast A and B Engine Rooms, where the auxiliary machinery spaces were omitted, but another void space, about three feet wide was substituted in its place. Above the SPS, and directly behind the armour belt, was a series of compartments, typically used for washrooms or storage spaces, which were designed to allow for upward venting of overpressure from a torpedo hit. This scheme was designed to protect against a 1000 lb warhead, and had been tested and found effective in full-scale trials. The SPS was also a key component of the ship's damage control system, as lists resulting from flooding could be corrected by counterflooding empty void spaces, and/or draining normally liquid filled compartments. In the case of the loss of the Prince of Wales these spaces were used for counterflooding to reduce list.

HMS Prince of Wales was sunk on 10 December 1941, from what was believed to have been hits by six aerial launched torpedoes and a 500 kg bomb. However, an extensive 2007 survey by divers of the wreck of Prince of Wales determined definitively that there had been only 4 torpedo hits. Three of these four hits had struck the hull outside the area protected by the SPS. In the case of the fourth, the SPS holding bulkhead appeared intact abreast the area where the hull was hit. The conclusion of the subsequent 2009 paper and analysis was that the primary cause of the sinking was uncontained flooding along "B" propeller shaft. The propeller shaft external shaft bracket failed, and the movement of the unsupported shaft then tore up the bulkheads all the way from the external propeller shaft gland through to B Engine Room itself. This allowed flooding into the primary machinery spaces. The damage and flooding was exacerbated by poor damage control and the premature abandonment of the after magazines and a telephone communications switchboard. "B" propeller shaft had been stopped, and then restarted several minutes after being struck by a torpedo. Subsequent inquiries into her loss at the time identified the need for a number of design improvements, which were implemented to a lesser or greater degree on the other four ships of the class. Ventilation and the watertightness of the ventilation system was improved, while internal passageways within the machinery spaces were redesigned and the communications system made more robust. Improved propeller shaft glands and shaft locking gear was introduced. Some of the supposed failures of the ship were nevertheless predicated on the assumption that a torpedo had hit and defeated the SPS at or about frame 206 at the same time as the hit that damaged B propeller shaft. The 2007 survey's video footage evidence showed however that the hull is basically intact in this area. The inability to survey the wreck during the war no doubt frustrated efforts to arrive at a definitive cause for the loss of Prince of Wales and, subsequently, that somewhat flawed analysis has led to a number of incorrect theories regarding the reasons for the sinking being inadvertently disseminated over the years.

On examination of the Prince of Wales after her encounter with the German battleship Bismarck and the heavy cruiser Prinz Eugen, three damaging hits were discovered which had caused about 400 tons of water, from all three hits, to enter the ship. One of these hits, fired from Bismarck, had penetrated the torpedo protection outer bulkhead in a region very close to an auxiliary machinery space causing local flooding within the SPS, while the inner, 1.5 inch ( 2x19 mm)  D-steel holding bulkhead, however, remained intact, as the German shell was a dud. The German shell would have actually exploded in the water if its fuse had worked properly, due to the depth which the shell had to dive before striking the Prince of Wales under her armoured belt.

Main armament


The King George V and the four other ships of the class as built carried ten BL 14 inch Mk VII naval guns, in two quadruple turrets fore and aft and a single twin turret behind and above the fore turret. There was debate within the Admiralty over the choice of gun calibre; though there was little or no debate within Parliament; other European powers preferred 15 inch, and the USN, 16 inch main guns. Initially the Admiralty studied vessels armed with a variety of differing main armament layouts including nine 15 in guns in three turrets, 2 forward and 1 aft. While this was well within the capabilities of the British shipyards, the design was quickly rejected as they felt compelled to adhere to the Second London Naval Treaty signed in 1936, and there was a serious shortage of skilled technicians and ordnance designers, along with compelling pressures to reduce weight. As a result, the class was designed to carry twelve 14-inch guns in three quadruple turrets and this configuration had a heavier broadside than the nine 15-inch guns. Unfortunately, it proved impossible to include this amount of firepower and the desired level of protection into a 35,000 ton displacement, and the weight of the superimposed quadruple turret brought the stability of the vessel into question. In the end, the second forward turret was changed to a smaller two gun turret in exchange for better armour protection, reducing the broadside weight to below that of the nine gun arrangement. The 14 inch Armour Piercing (AP) shell also carried a very large bursting charge of 48.5 lb. The last naval treaty had a clause that permitted a change to 16 inch guns if another signatory did not conform to it by 1 January 1937. Although they could have invoked this clause, the effect would have been to delay construction and it was considered prudent to build with 14 inch rather than find themselves without the new battleships. The U.S. opted to absorb a delay and built its ships with larger guns.

In service, the quad turrets proved to be less reliable than was hoped for. Wartime haste in building, insufficient clearance between the rotating and fixed structure of the turret, insufficient full calibre firing exercises and extensive arrangements to prevent flash from reaching the magazines made it mechanically complex, leading to problems during prolonged actions. Improved clearances, improved mechanical linkages, and better training led to greater reliability in the quadruple turrets but they remained controversial.

During the combat against the German battleship Bismarck, the main battery of the newly commissioned Prince of Wales had mechanical problems: it started to fire three-round salvos instead of five-round salvos, and there were problems in all except for the twin "B" turret. The main battery output was reduced to 74 percent during the engagement, as out of seventy-four rounds ordered fired, only fifty-five were possible. 'A' turret was taking in water leading to discomfort for its crew and "Y" turret jammed at salvo 20. The number of known defects in the main armament that was hampering 14 inch fire, the damage sustained and the worsening tactical situation forced Captain Leach to disengage from combat. With the range down to 14,500 yds and with five of his 14 inch guns out of action, Leach decided to break off his engagement with a superior enemy. Roskill in the War at Sea, volume 1, describes the decision to turn away:" In addition to the defective gun in her forward turret another 4 gun turret was temporarily incapacitated by mechanical breakdowns. In these circumstances Leach decided to break off the action and, at 0613, turned away under cover of smoke." During the later action with Bismarck, King George V was also having trouble with her main battery, and by 0927 every gun missed at least one salvo due to failures in the safety interlocks for antiflash protection. John Roberts wrote of main gunnery problems encountered by HMS King George V:

""At 0847 Rodney opened fire...at a gun range of 23500 yards, followed by King George V one minute later at 24,600 yards ...Initially she [KGV] did well achieving 1.7 salvos per minute while employing radar control but she began to suffer severe problems from 0920 onward [Note: KGV had opened fire at 0848 and fired for about 25 minutes at 1.7 salvos per minute until 0913, when the type 284 radar broke down, but with no recorded loss of 14 inch gun output until 0920. KGV recorded 14 straddles out of 34 salvos fired from 0853 to 0913, when using her type 284 radar for ranging and spotting ]. 'A' turret was completely out of action for 30 minutes [From 0920 ], after firing about 23 rounds per gun, due to a jam between the fixed and revolving structure in the shell room and Y turret was out of action for 7 minutes due to drill errors. . . Both guns in B turret, guns 2 and 4 in A turret and gun 2 in Y turret were put out of action by jams and remained so until after the action - 5 guns out of 10! There were a multitude of other problems with mechanical failures and drill errors that caused delays and missed salvos. There were also some misfires - one gun (3 of A turret) misfired twice and was out of action for 30 minutes before it was considered safe to open the breech.""

- John Roberts

During the early part of her action against the Scharnhorst at the Battle of the North Cape on 26 December 1943, HMS Duke of York (17) scored 31 straddles out of 52 broadsides fired and during the latter part she scored 21 straddles out of 25 broadsides, a very creditable gunnery performance. In total, Duke of York fired 450 shells in 77 broadsides. "However, HMS Duke of York still fired less than 70% of her possible output during this battle because of mechanical and "errors in drill" problems."

The KGVs were the only British battleships to use the 14 inch guns and turrets; their planned successors, free of treaty limitations, were to use a new 16 inch gun and triple mounts.

Secondary armament
The QF 5.25 inch Mark I dual purpose gun has been dogged with controversy as well. The RN Gunnery Pocket Book published in 1945 states that: "The maximum rate of fire should be 10–12 rounds per minute.". Wartime experience revealed that the maximum weight which the loading numbers could handle comfortably was much lower than 80–90 lb, and the weight of the 5.25 in ammunition caused serious difficulties, allowing them to manage only 7–8 rpm instead of the designed 10–12 rpm. The mount had a maximum elevation of only +70 degrees. The slow elevating and training speeds of the mounts were inadequate for engaging modern high-speed aircraft. Despite these failings, Prince of Wales was credited with several 5.25 inch kills during Operation Halberd, and damaged 10 of 16 high level bombers in two formations during her last engagement, two of which subsequently crash landed. HMS Anson (79) had her 5.25 inch turrets upgraded to RP10 control which increased training and elevating speeds to 20 degrees per second. These ships were equipped with the HACS AA fire control system and the Admiralty Fire Control Table Mk IX for surface fire control of the main armament.

Anti-aircraft
For anti-aircraft defence, the KGV were built with 4- and 8-barrelled QF 2 pounder "pom-pom" mounts and UP rockets. To this were added 20mm Oerlikon and 40mm Bofors guns.

The 2 pdr mounts were Director controlled - this placed the aiming of the guns separate from the guns themselves which generated large amounts of smoke and vibration. The mounts would be upgraded later with Remote Power Control and radar for improved performance.

The UP proved to be largely ineffective and were removed in the course of the war.

By the end of the war, the AA defences were more than 50 20mm, 8 40mm, and 88 2pdr guns in various single and multiple mounts. Anson carried 65 20 mm Oerlikons, six 8-barrel and six 4-barrel pom-poms by the end of the war.

Battle of the Denmark Strait
Two of five ships of the King George V class, the HMS Prince of Wales (53) and HMS King George V (41), participated in the Battle of the Denmark Strait. Prior to the battle,the German battleship Bismarck had left Gydnia in the Baltic, in preparation to break out of the North Sea into the Atlantic. She was accompanied by Prinz Eugen, four U-boats, two auxilliaries and five tankers. In the planning of the operation, the Scharnhorst and Gneisenau were also to have left Brest, France at the same time that Bismarck left Norway, to further threaten the British shipping. However, the British managed to severely damage both Scharnhorst and Gneisenau so that they were unfit for action. Because of this, the commander of the Bismarcks squadron, GroßAdmiral Günther Lütjens, urged his commanders to delay the operation until either Scharnhorst was repaired or Bismarcks sister Tirpitz was completed]].

The ships of the Home Fleet, HMS Prince of Wales, the battlecruisers HMS Hood (1918) and HMS Repulse, the aircraft carrier HMS Victorious (R38) (with 48 Hawker Hurricanes) and 20 cruisers and destroyers, were deployed to block Bismarck and Prinz Eugen's route to the Atlantic. The cruisers HMS Norfolk (78) and HMS Suffolk (55) were sent to guard the Denmark Strait, HMS Manchester (15), HMS Arethusa and HMS Birmingham (C19) were sent to defend the Iceland-Faeroes gap. However, the main fleet would be divided into two groups: Hood, flying the flag of Vice Admiral Lancelot Holland and Prince of Wales, and King George V, flying Admiral John Tovey's flag and Repulse, which was sent from the River Clyde. Also, two photo reconaissance Supermarine Spitfires were sent to Oslo and the Bergen fjords. The latter managed to find the Bismarck and Prinz Eugen at the end of his search, on May 22, 1941, and barely managed to take a few pictures of the ships he thought were cruisers. He was not spotted by either of the ships.

Soon after the disposition of the ships, Admiral John Tovey sent Prince of Wales, Hood, and the destoryers HMS Electra (H27), HMS Anthony (H40), HMS Echo (H23), HMS Icarus (D03), HMS Achates (H12) and HMS Antelope (H36) to cover the Greenland-Icelanand Iceland-Faeroes gap. He himself left Scapa Flow in King George V, with Victorious, the cruisers HMS Galatea (71), HMS Hermione (74), HMS Kenya and HMS Aurora (12), and the destroyers HMS Inglefield (D02), HMS Intrepid (D10), HMS Punjabi, HMS Windsor (D42) and HMS Lance (G87).

On May 23, 1941, the German ships were sighted by the Suffolk, which was followed by the Norfolk in the Denmark Strait. Both of these ships quickly reported their position and that of the Bismarck and Prinz Eugen to the Admiralty. At 2030, the Bismarck opened fire on the Norfolk, who quickly withdrew.

The ships continued through the Denmark Strait during the night, and at 0530, May 24, 1941, the HMS Hood and Prince of Wales sighted the German ships. The British ships opened fire on the Germans at 0600. The Bismarck's fifth salvo scored a fatal hit on the Hood. The Hood disappeared in a column of smoke, which gradually disappeared, and along with it, the battlecruiser HMS Hood.

Refits
The King George V class ships were refitted during the war to make improvements to AA defences and radar equipment and to make modifications for service in the Far East.

The ventilation was improved after reports of heat prostration on Prince of Wales during her last engagement.

In 1944, the aircraft capabilities (the Supermarine Walruses and the double-ended catapult) of King George V, Duke of York, Anson, and Howe were removed.

King George V was in refit during the early part of 1944. As well as the removal of the aircraft facilities, the A/A armament was altered. A quad pom-pom was removed and three octuple pom-poms added. Single barrelled Oerlikons were exchanged for six twin-barrel Oerlikons and quad mount 40mm Bofors. The radars were upgraded.

Duke of York was in refit from December 1942 to February 1943 and October 1944 to early 1945.

Howe went into refit and post refit trials for Pacific service from December 1943 to April 1944.

Anson was in refit from July 1944 to February 1945 for improvements to her AA and radar and then in trials (including the new Type 277P radar) until April.

Awards
Sergeant First Class Paul R. Smith decorations include: