Koning Willem I Class Battleships
Gunnery developments in the late 1890s and the early 1900s, led in the United Kingdom by Percy Scott and in the United States by William Sims, were already pushing expected battle ranges out to an unprecedented 6,000 yards (5,500 m), a distance far enough to force gunners to wait for the shells to arrive before applying corrections for the next salvo. A related issue was that the shell splashes from the more numerous smaller weapons tended to obscure the splashes from the bigger guns. Either the smaller-calibre guns would have to hold their fire to wait for the slower-firing heavies, losing the advantage of their faster rate of fire, or it would be uncertain whether a splash was due to a heavy or a light gun, making ranging and aiming unreliable. Another issue was that longer-range torpedoes were expected to soon be in service, and these would discourage ships from closing to ranges where the smaller guns' faster rate of fire would become preeminent. Keeping the range open generally negated the threat from torpedoes and further reinforced the need for heavy guns of a uniform calibre.
In 1903, the Italian naval architect Vittorio Cuniberti first articulated in print the concept of an all-big-gun battleship. When the Italian Navy did not pursue his ideas, Cuniberti wrote an article in Jane's Fighting Ships advocating his concept. He proposed an "ideal" future British battleship of 17,000 long tons (17,000 t), with a main battery of a dozen 12-inch guns in eight turrets, 12 inches of belt armor, and a speed of 24 knots (44 km/h; 28 mph). This led to the development of the HMS Dreadnought. This ship had such an impact when launched in 1906 that similar battleships built after her were referred to as "dreadnoughts," and earlier battleships became known as pre-dreadnoughts. Her design had two revolutionary features: an "all-big-gun" armament scheme and steam turbine propulsion. The arrival of the dreadnoughts renewed the naval arms race, principally between the United Kingdom and Germany but reflected worldwide, as the new class of warships became a crucial symbol of national power.
The Royal Netherlands Navy was in the early 20th century a modern and well-equipped navy, but lacked real firepower that battleships could provide. The Navy tried to react to this with the construction of the De Zeven Provincien class cruisers, which were equipped with four 11inch guns, but it soon became clear that these were no match for the dreadnoughts being constructed by the United Kingdom and Germany. When this shortcoming was finally recognized by the government the go-ahead was given to design and build two ''Slagkruisers'' (English: battlecruisers, officially classified as Dreadnoughts) for the Navy. As the Dutch did not have any experience in building these kind of ships, navy officials traveled to London to discuss possible help from the United Kingdom in constructing the new ships.
London agreed and in 1908 the construction of the ''Slagkruisers 1908'' started. The British naval engineers applied lessons learned from the Bellerophon Class battleships and the Dutch designed the hull. The ships were to become one of the first in the world with a double main battery, stacked behind each other instead of being placed midships. The class was to be named after King William the first of Orange-Nassau (William I of Frederick) and his wife Wilhelmina of Prussia.
The Koning Willem I Class were the first ships in the navy to use steam turbines in place of the older reciprocating triple-expansion steam engines. They each had two paired sets of Parsons direct-drive turbines, each of which was housed in a separate engine-room and drove two shafts. The wing shafts were coupled to the high-pressure ahead and astern turbines and the low-pressure turbines to the inner shafts. A cruising turbine was also coupled to each inner shaft, although these were not used often and were eventually disconnected. The four-bladed propellers were 8feet 10inches (2.69m) in diameter. The turbines were powered by eighteen Babcock and Wilcox water-tube boilers in three boiler rooms. They had a working pressure of 250 psi (1,724 kPa; 18 kgf/cm2). The turbines were designed to produce a total of 23,000 shaft horsepower (17,000 kW), but reached nearly 27,018 shp (20,147 kW) during trials in October 1906. Dreadnought was designed for 21 knots (38.9 km/h; 24.2 mph), but reached 21.6 knots (40.0 km/h; 24.9 mph) during trials.
Each ship carried 2,868 long tons (2,914 t) of coal, and an additional 1,120 long tons (1,140 t) of fuel oil that was to be sprayed on the coal to increase its burn rate. At full capacity, they could steam for 6,620 nautical miles (12,260 km; 7,620 mi) at a speed of 10 knots (19 km/h; 12 mph).
The ships was mounted with British 45-calibre BL 12 inch Mark X guns in four twin gun turrets. The four turrets were placed along the centreline of the ship, with the forward turrets (A&B) and aft turrets (X&Y). The guns could initially be depressed to −3° and elevated to 13.5°, although the turrets were modified to allow 16° of elevation during World War I, the same modification as applied by the British Navy. They fired 850-pound (390 kg) projectiles at a muzzle velocity of 2,725 ft/s (831 m/s); at 13.5°, this provided a maximum range of 16,450 m (17,990 yd) with armour-piercing (AP) 2 crh shells. At 16° elevation, the range was extended to 20,435 yd (18,686 m) using the more aerodynamic, but slightly heavier 4 crh AP shells. The rate of fire of these guns was one to two rounds per minute. The ships carried 98 rounds per gun.
The secondary armament consisted out of twelve BL 4-inch (101.6 mm) Mk VII guns that were positioned in the superstructure. The BL 4-inch gun Mk VII was a British high-velocity naval gun introduced in 1908 as an anti-torpedo boat gun in large ships, and in the main armament of smaller ships. They fired 20-pound projectiles at a muzzle velocity of 2,600 ft/s (790 m/s); this gave a maximum range of 9,300 yd (8,500 m). Their rate of fire was 12 rounds per minute. The ships carried three hundred rounds for each gun. Further more they were also equipped with eight QF 12 pounder 18 cwt naval guns that were placed on top of the superstructure. The QF 12 pounder 18 cwt gun was a 3 inch high-velocity naval gun used to equip larger British warships such as battleships for defence against torpedo boats. 18 cwt referred to the weight of gun and breech (18 × 112 lb = 2,016 lb or 914 kg), to differentiate the gun from others that also fired the "12 pound" (actually 12.5 lb or 5.7 kg) shell.
The class was also on of the first ships in the world to be fitted with an extensive AA battery. Each ships carried eight QF 6 pounder Hotchkiss guns. The QF 6 pounder Hotchkiss was a light 57 mm naval gun and coast defence gun of the late 19th century used by many countries, and was adapted for use anti-aircraft gun for the navy. They were placed on top of the turrets and strategically placed all over the ship.
The ships were both constructed at Wilton-Feyenoord in Rotterdam
8x BL 12-inch (304.5mm Mark X gun
12x BL 4-inch (101.6mm) Mk VII guns
8x QF 12-pounder (76mm) 18 cwt naval guns
8x QF 6-pounder (57mm) Hotchkiss guns
4x 18-inch (450 mm) torpedo tubes
The HMNLS Wilhelmine's forward turrets, under construction, 1909