Design work on what would become the
King Edward VII class began in 1901; the
Royal Navy had observed that foreign battleships, such as the Italian and the American , had begun to carry a heavy
secondary battery of guns. The design staff, operating without the direction of the
Director of Naval Construction,
William Henry White, who was ill at the time, began a series of studies for a battleship based on the preceding armed with a secondary battery of or guns. The Assistant DNC, J. H. Narbeth, initially had a great deal of trouble arranging the guns such that the secondary turrets did not interfere with the main battery guns. After examining the directly superimposed turrets used in the
Virginias, Narbeth concluded that it was not a workable solution, and so adopted an arrangement with four secondary turrets, one at each corner of the
superstructure. The
Admiralty provisionally accepted a draft equipped with eight 7.5 in guns in twin
gun turrets, but after White returned, he suggested the 9.2 in guns would be more effective against heavily armoured ships, and so the decision was made to switch to that armament. The heavy secondary guns added a great deal of weight high in the ship and they took up space on the deck, thus forcing the designers to make compromises to other aspects of the vessels, particularly the rest of the secondary battery. These guns, traditionally carried in
casemates, were relocated to a central box battery, since it would require less armour to protect the guns in such a compact arrangement. They were also mounted lower relative to the waterline, owing to the decreased
freeboard; this rendered the guns essentially unusable in anything but relatively calm seas. Combined with a higher
metacentric height, the low freeboard of the
King Edward VIIs made them prone to shipping water in heavy seas and excessive rolling. Despite the problems with their secondary armament, the ships were significantly more powerful than earlier British battleships and they compared well with foreign contemporaries. They nevertheless suffered the same fate as all late
pre-dreadnought battleships. Completed shortly before the advent of the all-big-gun in 1906, they were quickly rendered obsolescent, such that during the
First World War, the
King Edward VII-class ships were frequently deployed at the front of the
dreadnought battle squadrons to screen them for
naval mines, either by sighting or striking them before the dreadnoughts entered the area. The
King Edward VII class was the culmination of battleship design under the direction of White that had begun with the in the late 1880s. The follow-on class, the two s, were a major departure from previous designs and marked a transitional stage between pre-dreadnought and dreadnought-type battleships.
General characteristics The ships of the
King Edward VII class were
long between perpendiculars and
long overall. They had a
beam of and a
draft of . The
King Edward VII-class ships were more than a thousand tons heavier than earlier battleships
displacing normally and up to
fully loaded. The ships had of freeboard forward,
amidships, and aft. To save weight, the ships had their storage for food and other supplies reduced from a 4-month supply that was standard in previous designs to 3 months. Their crew varied over the course of their careers, ranging from 755 to 815; for example, after entering service, had a crew of 777 officers and
ratings; crews tended to increase during wartime.
King Edward VII and her
sister ships discarded the aft
conning tower that was standard practice in favour of a torpedo control tower that directed the firing of the stern
torpedo tubes. The ships were fitted with two heavy pole
masts; their foremasts were equipped with
tops used to mount
wireless telegraphy and
fire control equipment. , ,
Dominion, , and carried large, oval tops for most of their equipment and a smaller top below, while , , and had smaller, square tops, with two small tops lower on the masts. The
King Edward VIIs were the first British battleships with balanced rudders since the 1870s and were very manoeuvrable, with a tactical diameter of at . However, they were difficult to keep on a straight course, and this characteristic led to them being nicknamed "the Wobbly Eight" during their 1914–1916 service in the
Grand Fleet. They had a slightly faster roll than previous British battleship classes, but were good gun platforms, although very wet in bad weather.
Machinery The
King Edward VII-class ships were powered by a pair of 4-cylinder
triple-expansion engines that drove two inward-turning
screws, with steam provided by
water-tube or
fire-tube boilers of various types.
King Edward VII had ten
Babcock & Wilcox boilers and six
Scotch marine boilers, while
Africa,
Britannia,
Hindustan, and
Hibernia received eighteen Babcock & Wilcox boilers and three cylindrical return tube boilers.
New Zealand used eighteen
Niclausse boilers and three of the cylindrical return tube boilers, and
Dominion and
Commonwealth had sixteen of the Babcock & Wilcox boilers only. The reason multiple boiler arrangements were adopted was to compare the effectiveness of different boiler types. In service, the ships with mixed boiler types proved to be something of a disappointment, since the differing boiler types added complications to the powerplant and hampered efficient operation; they produced no benefit in return, and the experiments were not repeated in subsequent designs. The boilers were trunked into two
funnels located amidships. Primarily powered by coal, all of the class except
New Zealand had oil sprayers installed during construction, the first time this had been done in British battleships. These allowed steam pressure to be rapidly increased, improving the acceleration of the ships; this ability later led to the decision to adopt all oil-fired boilers in the
super-dreadnoughts.
New Zealands Niclausse boilers could not be adapted to use the oil sprayers. The
King Edward VII-class ships had a top speed of from , though some of the ships exceeded on speed trials, including
Dominion and
Hindustan. Using only coal, the ships had a cruising radius of about at an economical speed of , and with the supplemental fuel oil, their range increased to .
Armament The
King Edward VIIs had four
12-inch 40-calibre Mk IX guns mounted in twin-gun turrets fore and aft. The guns were carried in BVIIS-type mountings, which had a range of elevation from −5 degrees to +13.5 degrees and allowed loading the guns at any angle. The guns had a muzzle velocity of , and they were capable of penetrating 12 inches of Krupp armour at a range of . At their maximum elevation, the guns had a range of .
Commonwealth and
Zealandia later had their mounts modified to allow elevation to 30 degrees, which extended their maximum range significantly, to . These were supported by a heavy secondary battery of four
guns in four single turrets, two on each
broadside. The guns were carried in Mk VS mounts, which had a range of elevation from −7 to +15 degrees, allowing for a maximum range of . Muzzle velocity was . The first five ships also mounted ten
Mark VII 45-calibre guns, the same battery carried by earlier British battleships, though unlike earlier battleships, the
King Edward VIIs mounted these guns in a central battery rather than in casemates. The guns had a muzzle velocity of , and they could penetrate six inches of Krupp armour at . Maximum elevation was 14 degrees, which allowed the guns to engage targets out to . The last three ships (
Britannia,
Africa and
Hibernia) were instead fitted with
6-inch 50 calibre guns, which had been ordered for the
Warrior-class armoured cruisers, but were surplus when it was decided to complete the
Warriors with a secondary armament of guns. For defence against
torpedo boats, they carried fourteen
12-pounder guns and fourteen
3-pounder guns that were dispersed in pivot mounts around the ship. As was customary for battleships of the period, they were also equipped with five
torpedo tubes submerged in the
hull; two were on each broadside, with the fifth in the stern.
Armour Most of the heavy armour of the
King Edward VII class consisted of
Krupp cemented armour; this included most of the belt armour, main and secondary turrets and their
barbettes, and the conning tower. The armour layout of the
King Edward VII class was very similar to the protection scheme used in the and
London classes, with the primary change being the adoption of the armoured box for the 6-inch guns, rather than individual, armoured casemates. They had an armoured belt that was thick in the main portion of the belt; the transverse bulkhead on the aft end of the belt was thick. Aft of the transverse bulkhead, the side of the ship was protected with of Krupp non-cemented plate. Forward of the fore barbette, the belt was reduced to , then tapered to , then to at the extreme end of the bow. The upper edge of the main belt was reduced to thick, and above that was the battery deck for the 6-inch guns, which was protected with 7-inch-thick plate. The guns in the battery were divided with Krupp non-cemented screens. The armoured deck was 2 in of
mild steel, apart from the central portion of the hull, where it was reduced to and raised a deck level to the roof of the central battery. The reduction in thickness there was necessary to reduce topweight. The ships' main battery turrets had sides that were 8 to 12 inches thick, mounted atop 12-inch-thick barbettes. The 9.2-inch guns received thinner armour protection, with 5- to 9-inch sides; their barbettes were only thick, and they were reduced in height on the assumption that the side armour provided sufficient protection, and the likelihood of a shell exploding below the barbette in the ammunition hoists was very small. The conning tower had 12-inch sides.
Modifications The ships of the
King Edward VII class underwent a series of modifications over the courses of their careers. In 1907,
King Edward VII had some of her 12-pounder guns temporarily relocated to the main battery turret roofs, but this was found to be unsatisfactory and they reverted to their original locations that same year. Between 1907 and 1908, she and
Commonwealth,
Dominion,
Hindustan, and
New Zealand had their bridge-mounted 3-pounders removed. They also received
search lights in various positions, including the 9.2-inch turret roofs and the bridge wings. Funnel identification bands were added to all eight ships as well.
Hibernia and
Hindustan received
rangefinders on their aft superstructure in 1911–1912, and most of the ships had further alterations to their search lights.
Africa had experimental aircraft launching ramps installed on her bow in 1912 for flight tests, though the equipment was later transferred to
Hibernia that year, from which it was removed altogether. After the start of the First World War in August 1914,
Zealandia (ex-
New Zealand) gave one of her 12-pounders to arm a
Q-ship, receiving a pair of 3-pounders in its place. During a refit in that period,
Dominions bridge was enlarged. The 6-inch battery was removed from all of the ships of the class between 1916 and April 1917, with each ship having four of the guns re-mounted a deck higher in open pivot mounts in place of the 12-pounder guns that had been located there, where they were less affected by heavy seas, and thus, were more usable weapons. Additional search lights were installed during this period as well. In 1918,
Zealandia and
Commonwealth were heavily modernised for use as gunnery
training ships. Their pole masts were replaced with heavy tripod masts that were capable of supporting the latest fire control directors and rangefinders. Their remaining 12-pounder guns were removed and a pair of
anti-aircraft guns were added on the aft superstructure.
Commonwealth received
anti-torpedo bulges, though
Zealandia did not.
Commonwealth received
dazzle camouflage, and it has been reported that
Zealandia was similarly painted, but according to the naval historian R. A. Burt, the "lack of official and photographic evidence rules this out." ==Ships==