Yamato class
IJN YAMATO
The Yamato class were the largest and most powerful battleships ever built and the only ones to carry guns larger than
16in (406mm) except for the short-lived experiment of just one 18in gun mounted on the light battlecruiser HMS Furious in 1917. After 1936, when Japan withdrew from the 1922 and 1930 naval treaties, planning started on a class of five ships, each of 70,000 tonnes (full weight), mounting nine 18.1in (460mm) guns. The Yamato's were designed by naval architects Vice Admiral Professor Hiraga Yuzuru and Rear Admiral Fukuda Keiji. The ships were built in great secrecy in specially enlarged docks under massive 400t camouflage nets and served by specially-built 450t cranes. Named after ancient Japanese provinces, Yamato and hull No. 111 (proposed name Kii) were laid down at Mitsubishi Heavy Industries Kure in 1937 and 1939 respectively; Musashi at Nagasaki Naval Arsenal in 1931; Shinano at Yokosuka Naval Arsenal in 1939, but hull No.
797 was cancelled in 1942. In the event Shinano, after being 50% built, was completed as the then world's largest aircraft carrier in November 1944 (but sunk just ten days after completion) and hull No. 111 was broken up in 1942 when 30% completed, its materials used for the conversions of Ise and Hyuga into hybrid battleship-carriers. This left Yamato and Musashi completed in December 1941 and August 1942 respectively. The concept was quality to offset quantity, designed to be capable of engaging multiple enemy battleships at the same time.
The use of a shallow draught meant that the Yamato class had an immense beam. The narrow prow, ending in a large bulbous bow, achieved a remarkable
58% propulsive efficiency at 18 knots. To reduce weight the main armour belt, inclined at 20 degrees to the vertical, was incorporated as an integral part of the hull. The armour was intended to resist 18in (460mm) shells, or a bomb dropped from 15,000ft (4,575m). They had double, in places triple, bottoms and 1,174 separate watertight compartments, which incorporated torpedo protection with a multiple bulkhead side-protection system designed to withstand an 880lb (400kg) TNT charge. 12 Kampon boilers powered quadruple steam turbines, which in turn drove four 20ft (6m) propellers enabling a top speed of 27 knots.
The most striking feature was their forward superstructure, 12 stories high incorporating a four-man lift that ran up through an armoured shaft within the pagoda mast. Each of the nine 18.1in guns, mounted in triple-turrets, weighed 180 tons and fired a shell weighing 1.5 tons with a range of 23 miles (45.7km). The blast was such that the anti-aircraft mounts and boats were fitted with light-armoured shields. Secondary armament comprised 12 x 6.1in guns mounted in four triple turrets and 12 x 5in AA guns in six twin turrets, all of which were taken from the Mogami class cruisers when they were up-gunned with 8in armament. Two of the 6.1in midship turrets were removed later and replaced (on Yamato) by three additional 5in mounts each side, but in Musashi by three triple
IJN Yamato
Class: Yamato
Displacement: 72,809 tonnes
Length: 263m (862ft 10in)
Beam: 36.9m (121ft 1in)
Draft: 11.7m (38ft 5in)
Speed: 27 knots
Range: 13,358km (8,300 miles)
Crew: 2,500 men
Armament: 3 x triple 18.1in guns • 4 triple x 6.1in guns • 6 twin x 5in DP/AA guns • 162 x 25mm AA guns • 7 Nakajima E8N / Nakajima E4N float planes Armour: Decks - 230mm (9.1in), Waterline belt 410mm (16.1in)
IJN MUSASHI
Compared to her more famous sister, less has been written about Musashi, probably because she was the last to launch and the first to be sunk, operational for only two years and 87 days. Until lost, Musashi operated with Yamato during the Pacific War as units of Battleship Division 1. On 11 February 1943, Musashi replaced Yamato as flagship of the Combined Fleet, so that after Admiral Yamamoto was shot down and killed on 3 April by American fighters while en-route from New Britain to Bougainville, his cremated remains were flown back to Truck and placed in his cabin on board Musashi. On 24 June, while being refitted at Yokosuka, the battleship was visited by Emperor Hirohito. A photograph of Hirohito on the main deck with Musashi’s commanding officer, Captain Komura IJN and over 70 of his ship's officers, remains as a memento of his Highness's visit.
On 29 March 1944, Musashi was attacked by the submarine USS Tunny, which fired six torpedoes, one hitting near the bow which blew a hole 5.8m in diameter causing casualties and several thousand tons of water to flood the forward section. This took Musashi out of the war until 22 April. Partnering with Yamato as units of the Second Fleet during the June 1944 Battle of the Philippine Sea, Musashi escaped being attacked and returned undamaged to Japan.
The battleship's next operational sortie on 17 July was to transport the 106th Infantry Regiment to Lingga Island in Indonesia, after which she was replenished for inclusion in Operation Sho-Go, the Japanese plan to decoy the US Third Fleet away from San Bernardino Strait, thus allowing three strong Japanese naval forces to converge on Leyte in the Philippines and attack the virtually undefended American landing ships and transports.
During the Battle of Leyte Gulf, Central Force, commanded by Vice Admiral Kurita, was the most powerful of the three Japanese naval squadrons converging on Leyte. It comprised five battleships (including Yamato and Musashi), 12 cruisers and 15 destroyers. During passage on 23 October 1944 the destroyer Akishimo transferred 769 sailors to Musashi who had been rescued when their cruiser Maya had been torpedoed and sunk by the submarine USS Dace; their shipwrecked ordeal not yet over.
The next day on 24 October, while transiting the Sibuyan Sea, Kurita's fleet was spotted by a reconnaissance aircraft from the fleet carrier USS Intrepid. Just two hours later the Japanese ships came under attack from aircraft belonging to the carriers of US Task Force 38, the majority of them homing in on Musashi. Beginning at 9am and lasting until mid-afternoon, five multiple aerial attacks, a total of 250 sorties, descended upon Musashi, hitting her with an estimated 19 torpedoes and 17 bombs, all direct hits for the cost of only 18 aircraft. Listing at 10 degrees to port and down 26ft at the bow with her forecastle awash, counter-flooding of her boiler rooms stopped all power and at 7.30pm her crew were ordered to abandon ship. Mushashi capsized six minutes later and sank in over 3,000ft of water. 1,376 of her compliment were saved and the destroyer Shimakaze thankfully rescued 635 of Maya’s survivors before the giant battleship exploded underwater as she sank.
In 1985 the wreck of the Yamato was officially identified 180 miles (290km) South-West of Kyushu 1,120ft (340m) below the ocean in three main sections: part bow, two-thirds of the forward hull and part of the stern. However, it took more than 70 years to locate the wreck of Musashi. On 1 March 2015 the battleship was found 3,000ft (910m) down in the Sibuyan Sea off the Philippines. Survivor witnesses confirm that whilst the ship sank in one piece, it suddenly exploded once underwater. Musashi’s debris field is scattered across the ocean floor, the stern upside down and an upright partbow section, which held the circular steel mount for the Imperial Naval seal, is still intact. It used to incorporate a coloured chrysanthemum made out of teak, but that has long rotted away.
Unbeknown to the designers, the Yamato class suffered from a crucial design fault, confirmed when the wreck of Musashi was investigated by a Japanese team of
experts. The ‘unsinkable' torpedo defence system was their Achilles heel, because the joining between the ship's 16.1in thick upper-belt and their 7.9in thick lower-belt armour plating was riveted, not welded. At that time there was no technique to weld together steel plates of this thickness. When this part of the hull is impacted it creates a rupture-prone seam just below the waterline, making it susceptible to penetration by torpedoes. Joint failures have also been attributed to considerable damage inflicted upon Yamato from a single torpedo strike in 1943 and to the sinking of Shinano from four torpedo hits in 1944. In addition, all three vessels had much thinner armour protection on each side of their bows, evidenced from the extensive damage to Musashi when hit on the bow-side from a single torpedo in 1943. In 1936, when the Yamato class was being designed, the hierarchy of the
Japanese Imperial Navy, other than a few foresighted Admirals such as Isoroko Yamamoto, were still convinced that the traditional fleet action between battleships would prevail when the expected showdown with America inevitably took place. However, by the time the two superbattleships became operational in 1942-43, they were already obsolete due to the advent of air power. It is therefore ironic that the Japanese Navy was in the forefront of the development of aerial destruction of surface ships and that both battleships were sunk by carrier borne aircraft long before they came within striking range of the American fleet. During the final months of the war a saying going around the Japanese Navy was, “The three great follies of the world were the Great Wall of China, the Pyramids and the battleship Yamato!” Nevertheless, Yamato and Musashi hold a special place in the minds of today's naval enthusiasts.
IJN Musashi
Class: Yamato
Displacement: 72,880 tonnes
Length: 263m (862ft 10in)
Beam: 36.9m (121ft 0.8in)
Draft: 10.8m (35ft 5in)
Speed: 27 knots
Range: 13,358km (8,300 miles)
Crew: 2,800 men
Armament: 3 x triple 18.1in guns • 4 x triple 6.1in guns • 6 x twin 5in AA guns • 130 x 25mm AA guns • 7 Mitsubishi F1M/Aichi E13A mono-float planes Armour: Deck - 230mm (9.1in), Waterline belt 410mm (16.1in)