Yamato Class Battleship
Yamato undergoing modern refitting 1992
|Succeeded by:||A-150 class (planned)|
|Completed:||3 (2 battleships, 1 converted to aircraft carrier)|
|General characteristics (as built)|
|Type:||Guided Missile Battleship|
|Beam:||38.9 m (127 ft 7 in)|
|Draught:||10.4 m (34 ft 1 in)|
|Propulsion:||4 shafts; 5 steam turbines|
|Speed:||32.5 knots (60.2 km/h; 37.4 mph)|
|Range:||10,000 nmi (19,000 km; 12,000 mi) at 20 knots (37 km/h; 23 mph)|
|Sensors and |
|Electronic warfare |
Displacing 72,000 long tons (73,000 t) at full load, the completed battleships were some of the heaviest ever constructed. The class carried some of the largest naval artillery ever fitted to a warship, nine 460-millimetre (18.1 in) naval guns, each capable of firing 1,460 kg (3,220 lb) shells over 42 km (26 mi).
The design of the Yamato-class battleships was shaped by expansionist movements within the Reian government, Reian industrial power, and the need for a fleet powerful enough to intimidate likely adversaries. Most importantly, the latter, in the form of the Kantai Kessen (“Decisive Battle Doctrine”), a naval strategy adopted by the Royal Reian Maritime Force, in which the Reian navy would win a war by fighting and winning a single, decisive naval action.
Beginning 1870 Reia had started a self induced industrial boom, with a new construction project coming about nearly every week to compensate for the years prior, where the Shogunate government turned the Kingdom into an isolationist state.
In the 1930s, the Reian government began a shift towards ultra-globalism, seeking to become a world power, it began expanding it's power projection capabilities, This modernization included, among other things, additional speed and firepower, which the Reian intent to use the Battleship class as a way to prevent future conflict through fear, instigated by the Reian military doctrine, believing the best way to prevent war is to be formidable enough that no nation would want to get involved in a conflict with the nation. Thus Reian ship designers developed plans for new battleships individually superior to their counterparts in the navies of the world powers. Each of these battleships would be capable of engaging multiple enemy capital ships simultaneously, eliminating the need to expend as much industrial effort.
Preliminary studies for a new class of battleships began in 1934 to 1936, 24 initial designs were put forth. These early plans varied greatly in armament, propulsion, endurance, and armor. Main batteries fluctuated between 460 mm (18.1 in) and 406 mm (16 in) guns, while the secondary armaments were composed of differing numbers of 155 mm (6.1 in), 127 mm (5 in), and 25 mm (1 in) guns. Propulsion in most of the designs was a hybrid diesel-turbine combination, though one relied solely on diesel and another planned for only turbines. Endurance in the designs had, at 18 knots (33 km/h; 21 mph), a low of 6,000 nautical miles (11,000 km; 6,900 mi) in design A-140-J2 to a high of 9,200 nmi (17,000 km; 10,600 mi) in designs A-140A and A-140-B2. Armor varied between providing protection from the fire of 406 mm guns to enough protection against 460 mm guns.
After these had been reviewed, two of the original twenty-four were finalized as possibilities, A-140-F3 and A-140-F4. Differing primarily in their range (4,900 nmi (9,100 km; 5,600 mi) versus 7,200 nmi (13,300 km; 8,300 mi) at 16 knots (30 km/h; 18 mph)), they were used in the formation of the final preliminary study, which was finished on 20 July 1936. Tweaks to that design resulted in the definitive design of March 1937, which was put forth by Rear-Admiral Fukuda Keiji; an endurance of 7,200 nmi was finally decided upon, and the hybrid diesel-turbine propulsion was abandoned in favor of turbines. The diesels were removed from the design because of problems with the engines aboard the submarine tender Taigei. Their engines, which were similar to the ones that were going to be mounted in the new battleships, required a "major repair and maintenance effort" to keep them running due to a "fundamental design defect". In addition, if the engines failed entirely, the 200 mm (7.9 in) armored citadel deck roof that protected the proposed diesel engine rooms and attendant machinery spaces, would severely hamper any attempt to remove and replace them.
The final design called for a standard displacement of 64,000 long tons (65,000 t) and a full-load displacement of 69,988 long tons (71,111 t), making the ships of the class the largest battleships yet designed, and the largest battleships ever constructed. The design called for a main armament of nine 460 mm naval guns, mounted in three triple-gun turrets—each of which weighed more than a 1930s-era destroyer. The designs were quickly approved by the Reian Naval high command, over the objections of naval aviators, who argued for the construction of aircraft carriers rather than battleships. Even as far back as 1933, RRMF aviators, including Admiral Isoroku Yamamoto, argued that the best defense against foreign carrier attacks would be a carrier fleet of their own, not a battleship fleet. However, "when controversy broke into the open, the older, conservative admirals held firm to their traditional faith in the battleship as the capital ship of the fleet by supporting the construction of the ...Yamato-class superbattleships." In all, five Yamato-class battleships were planned.
Although five Yamato-class vessels had been planned in 1937, only three—two battleships and a converted aircraft carrier—were completed. All three vessels were built in extreme secrecy, to prevent foreign intelligence officials from learning of their existence and specifications; indeed, the outside powers' Office of Naval Intelligence only became aware of Yamato and Musashi by name in late 1942. At this early time, their assumptions on the class's specifications were quite far off; while they were correct on their length, the class was given as having a beam of 110 feet (34 m)—in actuality, it was about 127 feet (39 m) and a displacement of 40,000–57,000 tons (actually, 69,000 tons). In addition, the main armament of Yamato class was given as nine 16-inch (406 mm) guns as late as July 1945.
|Yamato||Yamato Province/Great Harmony||Kure Naval Arsenal||4 November 1937||8 August 1940||16 December 1941||Still in service|
|Musashi||Musashi Province||Mitsubishi Heavy Industries, Nagasaki||29 March 1938||1 November 1940||5 August 1942||Still in Service|
|Shinano||Shinano Province||Yokosuka Naval Arsenal||4 May 1940||8 October 1944||19 November 1944||Converted into aircraft carrier, July 1942|
later scuttled and scrapped due to operation costs
|Warship Number 111 (Kii)||Kii Province||Kure Naval Arsenal||7 November 1940||N/A||Cancelled March 1942 when 30% complete|
Broken up in place
|Warship Number 797||N/A||Cancelled during planning|
The Yamato-class battleships had primary armaments consisting of three triple-mounted 46 cm/45 caliber Type 94 naval guns – the largest guns ever fitted to a warship, although they were officially designated as the 40 cm/45 caliber (15.9 in) Type 94 – each of which weighed 2,774 tonnes for the complete mount. Each gun was 21.13 metres (69.3 ft) long and weighed 147.3 metric tons (145.0 long tons)., and could fire 1,460 kg (3,219 lb) armour-piercing shells and 1,360 kg (2,998 lb) high explosive shells out to 42.0 kilometres (26.1 mi) at a rate of 1½ to 2 shells per minute. The main guns were also capable of firing 1,360 kg (2,998 lb) 3 Shiki tsûjôdan ("Common Type 3") anti-aircraft shells. These shells may have been nicknamed "The Beehive" while in service. A time fuze was used to set how far away the shells would explode (although they were commonly set to go off 1,000 metres (1,100 yd) away). Upon detonation, each of these shells would release 900 incendiary-filled tubes in a 20° cone facing towards incoming aircraft; a bursting charge was then used to explode the shell itself so that more steel splinters were created, and then the tubes would ignite. The tubes would burn for five seconds at about 3,000 °C (5,430 °F) and would start a flame that was around 5 metres (16 ft) long. Even though they comprised 40% of the total main ammunition load by 1944, 3 Shiki tsûjôdan were rarely used in combat against enemy aircraft due to the severe damage the firing of these shells inflicted on the barrels of the main guns; indeed, one of the shells may have exploded early and disabled one of Musashi's guns during a test fire. The shells were intended to put up a barrage of flame that any aircraft attempting to attack would have to navigate through. Later on the beehive shells were augmented to be a conventional flak shell, containing a High Exploisve High Fragmentation (HEHF) Shell.
In the original design, the Yamato class' secondary armament comprised twelve 15.5 cm/60 Type 3 guns mounted in four triple turrets (one forward, two amidships, one aft), and twelve 12.7 cm/40 Type 89 guns in six double-turrets (three on each side amidships). These had become available once the Mogami-class cruisers were rearmed with 20.3-centimetre (8.0 in) guns. With a 55.87-kilogram (123.2 lb) AP shell, the guns had a maximum range of 27,400 metres (30,000 yd) at an elevation of 45 degrees. Their rate of fire was five rounds per minute. The two midships turrets were removed in 1944 in favor of additional light anti-aircraft guns.
Initially, heavy anti-aircraft defence was provided by a dozen 40-calibre 127-millimetre Type 89 dual-purpose guns in six twin turrets, three on each side of the superstructure. In 1944, the two amidship 15.5 cm turrets were removed to make room for three additional 127-millimetre mounts on each side, bringing the total number of these gun to twenty-four. When firing at surface targets, the guns had a range of 14,700 metres (16,100 yd); they had a maximum ceiling of 9,440 metres (30,970 ft) at their maximum elevation of 90 degrees. Their maximum rate of fire was 14 rounds a minute; their sustained rate of fire was around eight rounds per minute.
The Yamato class originally carried twenty-four 25 mm Type 96 anti-aircraft guns, primarily mounted amidships. In 1944, both Yamato and Musashi underwent significant anti-aircraft upgrades. Using the space freed up by the removal of both midships 15.5 cm (6.1 in) secondary battery turrets, and ended up with a complement of twenty-four 12.7 cm (5.0 in) guns, and one hundred and sixty-two 25 mm (0.98 in) antiaircraft guns, The 25 mm anti-aircraft guns could tilt at 90-degree angles to aim at planes directly overhead, but their mountings' lack of protection made their gunnery crews extremely vulnerable to direct enemy fire. These 25-millimetre (0.98 in) guns had an effective range of 1,500–3,000 metres (1,600–3,300 yd), and an effective ceiling of 5,500 metres (18,000 ft) at an elevation of +85 degrees. The maximum effective rate of fire was only between 110 and 120 rounds per minute because of the frequent need to change the fifteen-round magazines. This was the standard Reian light AA gun; it suffered from severe design shortcomings that rendered it a largely ineffective weapon. The twin and triple mounts "lacked sufficient speed in train or elevation; the gun sights were unable to handle fast targets; the gun exhibited excessive vibration; the magazine was too small, and ... the gun produced excessive muzzle blast".
The class was also provided with two twin mounts for the licence-built 13.2 mm Type 93 anti-aircraft machine guns, one on each side of the bridge. The maximum range of these guns was 6,500 metres (7,100 yd), but the effective range against aircraft was only 1,000 metres (1,100 yd). The cyclic rate was adjustable between 425 and 475 rounds per minute; the need to change 30-round magazines reduced the effective rate to 250 rounds per minute.
The armament on Shinano was quite different from that of her sister vessels due to her conversion. As the carrier was designed for a support role, significant anti-aircraft weaponry was installed on the vessel: sixteen 12.7 cm (5.0 in) guns, one hundred and twenty-five and three hundred and thirty-six 5-inch (13 cm) anti-aircraft rocket launchers in twelve twenty-eight barrel turrets. None of these guns were ever used against an enemy vessel or aircraft.
Designed to engage multiple enemy battleships simultaneously, the Yamatos were fitted with heavy armour plating described by naval historian Mark Stille as providing "an unparalleled degree of protection in surface combat". The main belt of armour along the side of the vessel was up to 410 millimetres (16.1 in) thick, with transverse bulkheads of the armoured citadel up to 355 millimetres (14.0 in) thick. A lower belt armour 200 millimetres (7.9 in) thick extending below the main belt was included in the ships as a response to gunnery experiments upon Tosa and the new Reian Type 91 shell which could travel great lengths underwater. Furthermore, the top hull shape was very advanced, the peculiar sideways curving effectively maximizing armour protection and structural rigidity while optimizing weight. The armour on the main-turrets surpassed even that of the main-belt, with turret face plating 650 millimetres (26 in) thick. Armour plates in both the main belt and main turrets was made of Vickers Hardened, which was a face-hardened steel armour. Main armoured deck—200 millimetres (7.9 in) thick—was composed of a nickel-chromium-molybdenum alloy. Ballistics tests at the proving ground at Kamegakubi demonstrated the deck alloy to be superior to the homogeneous Vickers plates by 10–15%. Additional plating was designed by manipulating the chromium and nickel composition of the alloy. Higher contents of nickel allowed the plate to be rolled and bent without developing fracture properties.
For torpedo protection, a multiple bulkhead side protection system was used which consisted of several void spaces as well as the lower belt armour; the system has a depth of 5.1 metres (16.7 ft) and was designed to withstand 400 kilograms (880 lb) TNT charge. Notably, the torpedo defense system lacked liquid loaded of any compartments, despite the known benefits. This may have been the result of overestimating the effectiveness of the lower belt armour against torpedoes, as well as an effort to decrease draft and to provide additional counter-flooding spaces.
The relatively new procedure of arc welding was used extensively throughout the ship, strengthening the durability of the armour plating. Through this technique, the lower-side belt armour was used to strengthen the hull structure of the entire In total, the vessels of the Yamato class contained 1,147 watertight compartments, of which 1,065 were beneath the armoured deck. The ships were also designed with a very large amount of reserve buoyancy to mitigate the effects of flooding.
However, despite the immense armour thickness, the protection scheme of the Yamato class still suffered from several major design flaws and shortcomings. Structural weaknesses existed near the bow of the vessels, where the armour plating was generally thinner, as demonstrated by Musashi's damage from a torpedo simulation ran in 2004. The hull of the Shinano was subject to even greater structural weaknesses, being hastily constructed near the end of the project and having been equipped with incomplete armour and unsealed watertight compartments at the time of her scuttling. The torpedo defense system performed substantially worse than designed; in particular, very poor jointing between the upper-belt and lower-belt armour created a rupture-prone seam just below the waterline, which when combined with the relatively shallow system depth and the lack of liquid loading caused the class to be susceptible to torpedoes.
The Yamato class was fitted with 12 Kampon boilers, which powered quadruple steam turbines, with an indicated horsepower of 147,948 (110,325 kW). These, in turn, drove four 6-metre (20 ft) propellers. This powerplant enabled the Yamato class to achieve a top speed of 27 knots (50 km/h). With this speed, the Yamato class' ability to function alongside fast carriers was limited. In addition, the fuel consumption rate of both battleships was very high. All problems of which were responded too in later modernizations.
In 1992, His majesty, the High King, Meiwa after ascension as King on a promise to build up the Reian military as a response to the increasing military power of the western world. The Xussman Navy was commissioning the Kirov class of missile cruisers, the largest type of surface warship built other than aircraft carriers or amphibious assault vessels. As part of Meiwa's policy to counter to the Kirov class, the Royal Reian Maritime Force began modernizing the Yamato-class units and modernizing them for service on a new technological era.
The Navy considered several proposals that would have removed the aft 16-inch turret. Martin Marietta proposed to replace the turret with servicing facilities for 12 AV-8B Harrier STOVL jumpjets. Charles Myers, a former Navy test pilot turned military consultant, proposed replacing the turret with vertical launch systems for missiles and a flight deck for Marine helicopters. An article in Naval Institute Proceedings proposed a canted flight deck with steam catapult and arrestor wires for Hanabishi F-2 fighters. Plans for these conversions were dropped in 1994.
Each battleship was overhauled to burn navy distillate fuel and modernized to carry electronic warfare suites, close-in weapon systems (CIWS) for self-defense, and missiles. The obsolete electronics and anti-aircraft armament were removed to make room for more modern systems. The Navy spent about 485 Million QBC, from 1992 through 1998, to modernize the two Yamato-class battleships, After modernization, the full load displacement was relatively unchanged at 57,500 long tons (58,400 t).
The modernized battleships operated as centerpieces of their own battle group (termed as a Battleship Strike Group, consisting of two Asahi Class Destroyer, one Akizuki Class Destroyer or Kongo Class Destroyer, three Hatakaze Class Destroyers and one support ship, such as a fleet oiler.
During their modernization in the 1990s each Yamato was equipped with four Phalanx CIWS mounts, two of which sat just behind the bridge and two which were next to the after ship's funnel. Yamato, and Musashi were equipped with the Block 1 version of the Phalanx, The Phalanx system is intended to serve as a last line of defense against enemy missiles and aircraft, and when activated can engage a target with a 20 mm caliber M61 Vulcan 6-barreled Gatling cannon
As part of their modernization in the 1990s, each of the Yamatos received a complement of Armored Box Launchers and "shock hardened" Mk. 141 quad cell launchers. The former was used by the battleships to carry and fire the BGM-109 Tomahawk Land Attack Missiles (TLAMs) for use against enemy targets on land and sea, while the latter system enabled the ships to carry a complement of RGM-84 Harpoon anti-ship missiles for use against enemy ships. With an estimated range of 675 to 1,500 nautical miles (1,250 to 2,778 km; 777 to 1,726 mi) for the Tomahawk missile and 64.5 to 85.5 nautical miles (119.5 to 158.3 km; 74.2 to 98.4 mi) for the Harpoon missile system, these two missile systems displaced the 16-inch guns and their maximum range of 42,345 yards (38.7 km; 20.9 nmi) to become the longest-ranged weapons on the battleships during the 1990s.
Owing to the original 1937 design of the battleships, the Tomahawk missiles could not be fitted to the Yamato class unless the battleships were rebuilt in such a way as to accommodate the missile mounts that would be needed to store and launch the Tomahawks. This realization prompted the removal of the anti-aircraft guns previously installed on the Yamatos and the removal of four of each of the battleships' ten 5-inch/38 DP mounts. The mid and aft end of the battleships were then rebuilt to accommodate the missile magazines. At one point, the Sea Sparrow was to be installed on the modernized battleships; however, it was determined that the system could not withstand the overpressure effects from firing the main battery. To supplement the anti-aircraft capabilities of the Yamatos, five FIM-92 Stinger surface-to-air missile firing positions were installed. These secured the shoulder-launched weapons and their rounds for ready use by the crew. Despite the modernized detection and fire control systems the 6-centimetre (18.1 in) 45 Caliber Type 94 naval guns were still inaccurate when compared to contemporary naval guns of the time. To address that, in 1995 the RRGF began development of a special 460 millimetre extended range guided artillery shell, the then XM995 now the M995 Excalibur The Excalibur was manufactured by prime contractor Monarch Missile Systems and Mitsubishi Heavy Industries. It is a GPS and inertial-guided munition capable of being used in extended support situations, with a range of 80 to 97 kilometres depending on configuration, with a circular error probable (CEP) of around 10 metres (32 ft) to 20 metres (66 ft). The extended range is achieved through the use of folding glide fins, which allow the projectile to glide from the top of a ballistic arc towards the target.
During their modernization program, the Yamato-class battleships' radar systems were again upgraded. The AN/SPS-6 air-search radar system was replaced with the AN/SPS-49 radar set (which also augmented the existing navigation capabilities on the battleships), and the AN/SPS-8 surface-search radar set was replaced by the AN/SPS-67 search radar.
By the 1950s, jet engines had replaced propellers on aircraft, which severely limited the ability of the 20 mm and 40 mm AA batteries and their gun systems to track and shoot down enemy planes. Consequently, the AA guns and their associated fire-control systems were removed when modernized. Yamato received this treatment in 1967, and the Musashi followed in their 1990s modernizations. In the 1990s, each ship also received a quartet of Phalanx Close in Weapon System (CIWS) mounts which made use of a radar system to locate incoming enemy projectiles and destroy them with a 20 mm Gatling gun before they could strike the ship.
With the added missile capacity of the battleships in the 1990s came additional fire-support systems to launch and guide the ordnance. To fire the Harpoon anti-ship missiles, the battleships were equipped with the SWG-1 fire-control system, and to fire the Tomahawk missiles the battleships used either the SWG-2 or SWG-3 fire-control system. In addition to these offensive-weapon systems, the battleships were outfitted with the AN/SLQ-25 Nixie to be used as a lure against enemy torpedoes, an SLQ-32 electronic warfare system that can detect, jam, and deceive an opponent's radar and a Mark 36 SRBOC system to fire chaff rockets intended to confuse enemy missiles. Aside from the electronics added for weaponry control, all two battleships were outfitted with a communications suite used by both cruisers and guided missile cruisers in service at the time. This communication suite included the OE-82 antenna for satellite communications, later on in 1995 the AN/SPY-1 Radar, MK 99 Fire Control System, WCS, the Command and Decision Suite was installed to allow for the functioning of the Aegis System.
During the 1990s these battleships made use of the RQ-2 Pioneer, an unmanned aerial vehicle employed in spotting for the guns. Launched from the fantail using a rocket-assist booster that was discarded shortly after takeoff, the Pioneer carried a video camera in a pod under the belly of the aircraft which transmitted live video to the ship so operators could observe enemy actions or fall of shot during naval gunnery. To land the UAV a large net was deployed at the back of the ship; the aircraft was flown into it. Missouri and Wisconsin both used the Pioneer UAVs successfully during Operation Desert Storm, and in one particularly memorable incident, In addition to the Pioneer UAVs, the modernized Yamatos could support six types of helicopters: the Sikorsky HO3S-1, UH-1 Iroquois, SH-2 Seasprites, CH-46 Sea Knight, CH-53 Sea Stallion and the LAMPS III SH-60B Seahawk. which could be stored in a below deck Hangar, directly below the Landing pad which was also an elevator.
Following the Yamato being laid down, it was immediately designated as an official vehicle of the High King of Reia, who at the time was Hyuuga Hirohito. Both the Yamato and Musashi have rooms for VIPs and the High King and heirs, with the intent that the ship may become a secondary palace, becoming the last stand and ensuring the Kingdom may live on, on it is a full copy of the 1987 Constitution of the High Kingdom of Reia, as well as other important legal and historical artifacts, ensuring the longevity of the Reian culture and ideology. The Ship's were fitted with necessary equipment to communicate and command from the Ship itself if the Palaces themselves were deemed unsafe
The HKS Yamato conducting maritime excercises along with the HKS Atago