Japanese battleship Yamato

From Wikipedia, the free encyclopedia

Career
Yamato on trials, 1941
Ordered:	March 1937
Laid down:	4 November 1937
Launched:	8 August 1940
Commissioned:	16 December 1941
Fate:	Sunk 7 April 1945 North of Okinawa
General characteristics
Displacement:	65,027 tonnes (empty, including 21,266 tonnes of armor); 72,800 tonnes (estimated, full load)
Length:	256 m (800.5 ft) water-line 263 m (862.5 ft) overall
Beam:	36.9 m (121 ft)
Draft:	11 m (36 ft) maximum
Propulsion:	• 12 Kanpon boilers, driving 4 steam turbines • 150,000 shp (110 MW) • Four 3-bladed propellers, 6.0 m (19.7 ft) diameter
Speed:	27 knots (50 km/h)
Range:	11,500 km at 16 knots (30 km/h)
Complement:	2,750
Armour:	• 650 mm on face of turrets • 410 mm side armor, inclined 20 degrees • 200 mm armored deck
Armament: (1941)	• 9 × 46 cm (18.1 inch) (3×3) • 12 × 15.5 cm (6.1 inch) (4×3) • 12 × 12.7 cm (6×2) • 24 × 25 mm AA (8×3) • 4 × 13 mm AA (2×2)
Armament: (1945)	• 9 × 46 cm (18.1 inch) (3×3) • 6 × 15.5 cm (6.1 inch) (2×3) • 24 × 12.7 cm (12×2) • 162 × 25 mm AA (52×3, 6×1) • 4 × 13 mm AA (2×2)
Aircraft:	7, 2 catapults

Yamato (大和), named after the ancient Japanese Yamato Province, was a battleship of the Imperial Japanese Navy. She was the first built (the lead ship) of the Yamato class. She and her sister ship Musashi were the largest, heaviest battleships ever constructed, weighing 72,802 tons at full load. She carried the heaviest armament ever fitted to a battleship: nine 460 mm (18.1 inch) guns.

1 Construction
2 Unique design features
3 Combat
4 References
5 Trivia
6 External links

[edit] Construction

Yamato under construction

The Yamato class were designed in the post Washington Naval Treaty period. The treaty had been extended by the London Naval Treaty of 1930 which limited the signatories to no battleship production before 1937; the Japanese withdrew from the Treaty at the Second London Conference of 1936. Design work on the class began in 1934 and after modifications the design for a 68,000 ton vessel was accepted in March 1937. The Yamato was built in intense secrecy at a specially prepared dock to hide her construction at Kure Naval Dockyards beginning on 4 November 1937. She was launched on 8 August 1940 and commissioned on 16 December 1941. Originally it was intended that five ships of this class would be built, but the third ship of the class, Shinano, was converted to an aircraft carrier during construction after the defeat at the Battle of Midway, the un-named "Hull Number 111" was scrapped in 1943 when roughly 30% complete, and "Hull Number 797", proposed in the 1942 5th Supplementary Program, was never ordered. Plans for a "Super Yamato" class, with 50.8 cm (20 inch) guns, provisionally designated as "Hull Number 798" and "Hull Number 799", were abandoned in 1942.

The class was designed to be superior to any ship that the United States was likely to produce. The 46 cm (18.1 inch) main guns were selected over 40.6 cm (16 inch) because the width of the Panama Canal would make it impractical for the U.S. Navy to construct a battleship with the same caliber guns without severe design restrictions or an inadequate defensive arrangement. To further confuse the intelligence agencies of other countries, her main guns were officially named as 40.6 cm Special, and civilians were never notified of the true nature of the guns. Their budgets were also scattered among various projects so that the huge total costs would not be immediately noticeable.

At the Kure Navy Yard, the construction dock was deepened, the gantry crane capacity was increased to 100 metric tonnes, and part of the dock was roofed over to prevent observation of the work. Arc welding, a relatively new procedure at that time, was used extensively. The lower side-belt armor was used as a strength member of the hull structure. This was done to save weight, an important concern for the designers, despite the lack of treaty limitations.

[edit] Unique design features

The Yamato was designed by Keiji Fukuda and followed the trend of unique and generally excellent indigenous Japanese warship designs begun in the 1920's by Fukuda's predecessor Yuzuru Hiraga. The design of Yamato contained a number of unique features, some of which contributed to the striking appearance of the vessel. To begin with, like most of the designs of the 20's and 30's the Yamato's deck line was not level, but rose and fell through the length of the hull. The undulating line of the main deck forward saved structural weight without reducing hull girder strength. Tests of models in a model basin led to the adoption of a semitransom stern and a bulbous bow, which reduced hull resistance by 8%. The nine 18.1-inch main armament cannons were the largest ever fielded at sea, a major technological challenge to construct and operate. Their successful implementation in the Yamato class battleships constitutes a major achievement on the part of Japanese naval constructors. The exponentially higher blast effect of the main armament prevented the stowage of boats on deck or the stationing of unshielded personnel in combat. As a result, all anti-aircraft positions (even the smallest) were enclosed in blast shields as designed. Later in their career the anti-aircraft armament of both ships were considerably augmented by open positions of both light and heavy weapons. Presumably AA gun crews would evacuate the weather deck prior to the firing of the main armament. Incidentally this might be the reason for the Yamato's ineffectiveness at the Battle off Samar; the ship was under almost continual air attack and may have been prevented from firing her main armament at the risk of killing or disabling gunners in open positions. For similar reasons the superstructure of the ship was extremely compact, which reduced armored citadel length but also hampered anti-aircraft arcs of fire. Boats were stowed in below-deck hangars and launched via an unusual traveling crane arrangement mounted on both quarters. The quarter deck aft of turret 3 was paved with concrete, beneath which a hanger for the stowage of up to seven spotter aircraft was provided for via a wide elevator-like opening in the stern. Contrary to some descriptions the Yamato and Musashi did not have 'Pagoda' masts as did previous Japanese battleships, but modern tower bridge structures to house command and fire control facilities. The mainmast, funnel and tower bridge were all unique in design and appearance, differing markedly both from other Japanese battleships and from capital ships of other navies. There is a general 'familial' resemblance however between the architecture of the Yamatos and the Hiraga/Fujimoto designed series of cruisers of the 1920s and 30s, particularly the Takao and Mogami classes. The immense beam (girth) of these ships made them perhaps the most stable of all battleships. Both ships were reported to be very stable even in heavy seas. However the increased width of the hull also meant that loss of stability required a correspondingly greater righting-arm to correct in the event of significant flooding. The ship had one single large rudder (at frame 231), which gave it a small (for a ship of that size) turning circle of 640 meters. By comparison the US Iowa class fast battleship had one of over 800 m. There was also a smaller auxiliary rudder installed (at frame 219) which was virtually useless. The steam turbine power plant was a relatively low powered design (25 kgf/cm² (2.5 MPa), 325 °C), and as such, their fuel usage rate was very high. This is a primary reason why they were not used during the Solomon Islands campaign and other mid-war operations. There were a total of 1147 watertight compartments in the ship.

[edit] Combat

Battle of the Sibuyan Sea, 24 October 1944. Yamato is hit by a bomb near her forward 460 mm gun turret, during attacks by U.S. carrier planes as she transited the Sibuyan Sea. This hit did not produce serious damage.

Yamato was the flagship of Admiral Isoroku Yamamoto from 12 February 1942, replacing Nagato. She participated in the Midway operation in June, 1942, but took no active part in the Battle of Midway. She remained the flagship for 364 days until February 11, 1943, when the flag was transferred to her sister ship Musashi. From 29 August 1942 to 8 May 1943, she spent all of her time at Truk, being underway for only one day during this entire time. In May 1943, she returned to Kure, where the two wing 15.5 cm turrets were removed and replaced by 25 mm machine guns, and Type-22 surface search radars were added. She returned to Truk on 25 December 1943. On the way there, she was damaged by a torpedo from the submarine USS Skate, and was not fully repaired until April 1944. During these repairs, additional 12.7 cm anti-aircraft guns were installed in the place of the 15.5 cm turrets removed in May, and additional 25 mm anti-aircraft guns were added.

She joined the Japanese fleet in the Battle of the Philippine Sea in June 1944. In October, she participated in the Battles of Leyte Gulf and Samar, during which she first fired her main guns in anger. She received two bomb hits from aircraft which did little damage. She returned home in November and her anti-aircraft capability was again upgraded over the winter. She was attacked in the Inland Sea on March 19, 1945 by carrier aircraft from Task Force 58 as they attacked Kure, but suffered little damage.

Yamato exploding

Her final mission was as part of Operation Ten-Go following the invasion of Okinawa on 1 April 1945. She was sent on a suicide mission (commanded by Admiral Seiichi Ito) to attack the US fleet supporting the US troops landing on the west of the island. On 6 April Yamato and her escorts, the light cruiser Yahagi and 8 destroyers, left port at Tokuyama. They were sighted on 7 April by American submarines as they exited the Inland Sea southwards. The U.S. Navy launched 386 aircraft to intercept the task force, and the planes engaged the ships starting at 12:30 that afternoon. Yamato took 8 bombs and 10 torpedo hits before, at about 14:23, she capsized to port and her aft magazines detonated. She sank while still some 200 km from Okinawa. Of her crew 2,475 were lost, and the 269 survivors were picked up by the escorting destroyers. Some reports claim that a number of survivors were machine-gunned in the water by U.S. aircraft.^[1] However, other Japanese survivors reported that U.S. aircraft temporarily halted their attacks on the Japanese destroyers during the time that the destroyers were busy picking up survivors from the water^[2].

The wreckage lies in around 300 meters of water and was surveyed in 1985 and 1999. These surveys show the hull to be in two pieces with the break occurring in the area of the second ('B') main turret.

The senior surviving bridge officer Mitsuru Yoshida, claims that a fire alert for the magazine of the forward superfiring 6-inch guns was observed as the ship sank. This fire appears to have detonated the shell propellant stored as the ship rolled over, which in turn set off the magazine in turret 'B' resulting in the famous pictures of the actual explosion and subsequent smoke column photographed by US aircraft (shown above and recorded as being seen in southern Japan, one hundred miles away).

The bow section landed upright, with the stern section remaining keel up. The three main turrets fell away as the ship turned turtle and landed in the wreckage field around the seperated hull pieces.

A further large hole was found in the stern section, strongly suggesting that a third magazine explosion occurred, possibly the aft superfiring 6" gun magazine.

Further examples of capital ships being lost due to magazine detonations of this nature during or after battle are the British battlecruisers HMS Queen Mary, Invincible and Indefatigable at the battle of Jutland in 1916, Hood at battle of the Denmark Strait in 1941, USS Arizona at Pearl Harbor in 1941 and HMS Barham in the Eastern Mediterranean in 1941.

[edit] References

Yoshida Mitsuru, Requiem for Battleship Yamato. A detailed description of the ship's final voyage; Mitsuru was the only surviving bridge officer.
Janusz Skulski, The Battleship Yamato. A highly detailed book on every aspect of the ship.
Russell Spurr's A Glorious Way To Die. A description of Yamato’s final days as seen from the perspective of not only her officers and men, but also the accompanying ships of her task force and the American forces who destroyed her.
Siegfried Breyer, Battleships and Battlecruisers 1905–1970 (Doubleday and Company; Garden City, New York, 1973) (originally published in German as Schlachtschiffe und Schlachtkreuzer 1905–1970, J.F. Lehmanns, Verlag, Munchen, 1970). Contains various line drawings of the ship as designed and as built.
Robert Gardiner, ed., Conway’s All the World’s Fighting Ships 1922–1946, (Conway Maritime Press, London, 1980)
William H. Garzke, Jr., and Robert O. Dulin, Jr., Battleships: Axis and Neutral Battlehips in World War II, (Naval Institute Press, Annapolis, 1985)
James D. Hornfischer, The Last Stand of the Tin Can Sailors : The Extraordinary World War II Story of the U.S. Navy's Finest Hour, (Bantam; Reprint edition, 2005). Detailed story of the Battle off Samar (although light on details from the Japanese perspective) and the most intensive treatment available of Yamato’s only surface action.
Axelrod, David (Writer and director). (2005) NOVA, Sinking the Supership [Video documentary]. Boston: WGBH Educational Foundation and Bang Singapore Private Limited. — One-hour documentary on Operation Ten-Go

^ "Then the Americans started to shoot with machine guns at the people who were floating, so we all had to dive under." Naoyoshi Ishida; Keiko Bang (September 2005). Survivor Stories: Ishida. Sinking the Supership. NOVA.
^ Yoshida, Requiem, 144.

[edit] Trivia

A 46 cm shell at the Yasukuni Shrine

In 2005, a Yamato museum opened in Kure, Hiroshima. A 1:10 scale model of the ship can be seen there.
A film based on the Yamato and her crew: Otoko-tachi no Yamato, was made in 2005.
The ship is frequently referenced in Japanese popular culture, most notabably in the futuristic anime television and movie series Space Battleship Yamato, broadcast in English as Star Blazers.