Battleship - Senkan (English spelling) battleship

Japanese: 戦艦 - せんかん（英語表記）battleship

A warship with the most powerful guns and robust defenses, it was the main force of the fleet, and its main mission was to destroy enemy ships by bombardment at sea. It was equipped with many large caliber guns, and thick armor was attached to the sides, decks, and main gun turrets of the main hull to withstand hits from its own main guns. It also had underwater defenses against torpedo and mine explosions, so the size of the ship was large, and until World War II, it was the largest warship, except for a few large aircraft carriers. Its speed was several knots or about 10 knots slower than high-speed ships such as cruisers and destroyers of the same period. Since its appearance in the late 19th century, it was the main force of the navy until World War II, and the number of battleships and the power of each individual ship were considered symbols of national power, and had a great influence on politics and diplomacy. However, during World War II, aircraft and aircraft carriers became the main force of the navy, so the battleship lost its military value and became a thing of the past. After the war, they were gradually decommissioned by each country, and now they have all disappeared except for memorial ships and decommissioned ships kept in storage.

[Yasuo Abe]

History of the Battleship

Age of sail

The origin of the battleship can be traced back to the ships of the line that appeared in the second half of the 17th century. These were wooden warships equipped with sails and whose mission was to form a line of battle and engage enemy fleets by firing multiple broadsides at once. A representative example of this was the Victory (2,162 tons, 100 guns), which served as the flagship of Admiral Nelson, commander-in-chief of the British fleet, in the Battle of Trafalgar in 1805.

[Yasuo Abe]

From the Birth of Ironclad Ships to the Russo-Japanese War

In the 19th century, technological innovations such as the practical application of steam engines and the invention of howitzers that fire explosive shells progressed. In response to the increasing power of naval guns, iron clad ships with thick armor plates on the waterline of the ships' sides were built, replacing the ships of the line. The first ship was the French Gloire (5,600 tons, 12.8 knots), launched in 1859, which was a steam-powered ship with a wooden hull covered in 10 cm thick armor plates and 30 16 cm cannons on the sides. In response to this, the British Warrior (9,000 tons, 14.3 knots, 38 20 cm cannons), launched in 1860, was the first ironclad ship, and this evolved into battleships, battlecruisers, large armored cruisers, and so on. After the appearance of these two ships, ironclad ships of 5,000 to 10,000 tons equipped with powerful artillery were built in each country, and the number of main guns mounted decreased while the caliber became larger. Following the early broadside ships, casmate ships appeared, which had their main guns mounted in a defensive casemate in the center of the hull, and turret ships, which had swivel turrets, were built in the late 1860s. With the development of steam engines, sails were abandoned and the method of mounting swivel turrets on the deck improved, leading to the central turret ships, which had two turrets arranged in a trapezoid shape above the central defensive compartment, being built in the 1870s, and barbette ships, which had turrets mounted on the centerline of the front or fore and aft parts of the hull, appearing in the early 1880s.

Around 1880, breech-loading rifled guns were developed to replace the conventional muzzle-loading smoothbore guns, and their firing power and accuracy improved significantly. The British Royal Sovereign Class (14,150 tons, 16.5 knots), completed in 1892, was equipped with four 34-cm breech-loading rifled guns in open turrets and had 45.7-cm thick armor plates on the sides of its ships, giving it well-balanced offensive and defensive capabilities as well as excellent seaworthiness, and it became the forerunner of modern battleships. From this time on, the term battleship came to be used instead of the conventional armored ships and turret armored (ironclad) ships. The main guns were further developed into turrets with bulletproof protection all around, and although the caliber was reduced to 30 cm, their firing power was greater than that of the conventional 40-43 cm guns. For defensive armor, Harvey armor was invented, which used carbonization technology to significantly improve bullet resistance, and Krupp armor and Vickers armor were developed as improvements on this. These technological advances were incorporated into the British Majestic Class (14,900 tons, 17 knots), which was completed in 1895, and this established the basic form of battleships. This class was equipped with one twin 30 cm gun turret at the front and rear, which became the standard main armament for battleships thereafter, and many ships of this type were built in various countries until the appearance of the Dreadnought class battleships (details below). This includes Japanese battleships (all British-made) during the Russo-Japanese War, such as the Mikasa (15,140 tons, 18 knots, four 30 cm guns), all of which were the most elite ships of their time.

At the time, the distance of artillery fire was generally within 7,000 meters, so defense focused on bulletproof protection provided by waterline armor plates on the sides of the ships, with little consideration given to underwater defense.

[Yasuo Abe]

From just after the Russo-Japanese War to the Washington Conference

During the Russo-Japanese War, the first battle between battleships took place, and it became clear that battleships equipped with large caliber guns had the decisive power to decide the outcome of naval battles, and that no strong ship could resist their concentrated fire. This led to the establishment of the doctrine of big ships and big guns. Based on this lesson, Britain abolished intermediate guns and 15 cm secondary guns and equipped as many main guns as possible (single caliber main gun doctrine), and in 1906 completed the innovative battleship Dreadnought (18,110 tons, 21 knots, five twin 30 cm guns), which achieved a speed of over 20 knots by adopting steam turbines instead of the conventional reciprocating steam engines, and this instantly made conventional battleships worthless. Such single caliber main gun battleships were called Do-class battleships, after the first letter of the ship's name, Do. At the same time as Dreadnought, Britain also equipped a large armored cruiser with gun power equivalent to that of a dreadnought battleship and further improved its speed by completing the Invincible Class battlecruiser (17,250 tons, 26.5 knots, eight 30 cm guns) in 1908. Ships of both types were built in competition with each other as capital ships by various countries.

The caliber of the main guns increased steadily from 30 cm to 34 cm, 36 cm, and 38 cm, and ships equipped with guns of 34 cm or more were called super-dreadnought ships. As the caliber of the main guns increased, defenses were also strengthened, and ships gradually became larger, with ships of nearly 30,000 tons appearing during World War I.

The lessons learned from the Battle of Jutland in 1916 required strengthening deck defense (horizontal defense) against large-angle shells in long-range artillery battles, strengthening underwater defense against near-missiles and torpedo explosions, fireproofing and fire prevention measures for ammunition magazines, and the development of emergency measures against large-scale flooding and fires. Ships incorporating these measures were built in the UK, the US, and Japan toward the end of World War I and after the war, and these ships were called the Post-Jutland type. Japan's Nagato class (33,800 tons) not only strengthened its defenses, but also led the way in adopting 40-centimeter guns as its main guns, and furthermore used all-geared turbines and heavy oil-fired boilers for its engines, making it a high-speed battleship with a speed of 26.5 knots. A fast battleship combines the offensive and defensive power of a battleship with the speed of a battlecruiser. Britain led the way in World War I, and all the flagships of Japan's 8-8 fleet plan were designed as this type.

[Yasuo Abe]

From the Washington Conference to World War II

The Washington Naval Treaty of 1922 established limits on the number of battleships owned and new constructions by the UK, the US, Japan, France and Italy (standard displacement of 35,000 tons, main gun caliber of 40cm or less), putting an end to the race to build capital ships and causing many existing and unbuilt ships to be scrapped. The British Nelson Class (33,950 tons, 23 knots, nine 40cm guns), completed in 1927, was the only battleship built in accordance with the provisions of the treaty, and was the first ship to adopt a thorough centralized defense system, with all triple main guns concentrated at the front, which had a major influence on the design of battleships by various countries thereafter.

After that, the construction of the German armored ship Deutschland Class (11,700 tons, 26 knots, six 28 cm guns, completed in 1933) prompted the construction of medium-sized, fast battleships of 26,000 to 32,000 tons equipped with 28 to 33 cm guns in Europe. Then, construction of full-scale battleships of 35,000 tons equipped with the largest caliber guns began, and when the disarmament treaty expired at the end of 1936, the United States, Britain, and Japan also began construction of new battleships. These were equipped with large-caliber guns of 36 cm or more, had excellent long-range artillery combat capabilities of 30,000 meters, were heavily defended, fast battleships, and were equipped with numerous anti-aircraft armaments such as anti-aircraft guns and machine guns. Representative ships of this period included the British King George V Class (36,750 tons, 27.5 knots, ten 36 cm cannons), the American North Carolina Class (38,000 tons, 28 knots, nine 40 cm cannons), the Iowa Class (48,500 tons, 33 knots, nine 40 cm cannons), and the Japanese Yamato class (64,000 tons, 27 knots, nine 46 cm cannons). Germany, Italy, and France also built fast battleships similar to those of the British and Americans, all of which were completed just before and during World War II.

Due to the development of aircraft and aircraft carriers, there were no more opportunities for battleships to engage in naval battles at sea during World War II, and it became clear that no matter how well-defended a battleship was, it could not withstand the concentrated torpedo and bomb attacks of numerous aircraft. As a result, battleships lost their long-held position as the main force of the navy, and were used for direct escort of aircraft carrier task forces, fleet flagships, land bombardment, convoy escort, etc.

[Yasuo Abe]

Current Battleships

After World War II, battleships from each country were gradually scrapped, and by the mid-1960s, all but four American Iowa-class ships had disappeared. The United States used these ships for land bombardment in the Korean War and the Vietnam War, and from the early 1980s they were recommissioned after undergoing modernization work, including the installation of Tomahawk cruise missiles and Harpoon anti-ship missiles, in order to use them as core ships of the surface strike force. Two of these ships also participated in the Gulf War. From 1990 to 1992, all four ships were placed in reserve, and in 1995 they were struck from the list, bringing to a close the history of these battleships.

[Yasuo Abe]

"The World's Battleships: Big Ships and Big Guns" (1998, Sekai Bunka Publishing)" ▽ "The World's Battleships: Dreadnought Battleships" (1999, Sekai Bunka Publishing)" ▽ "The World's Battleships - A History of the Development of Battleships that Dominated Fleet Battles with Superior Gunpower and Armor: Rekishi Gunzo, Pacific War History Series 41" (2003, Gakken)" ▽ "The World's Ships Special Issue Vol. 83: History of Modern Battleships" (2008, Kaijinsha)" ▽ "The Collected Works of Fukui Shizuo 1: The Story of Japanese Battleships I" (2008, Kojinsha)" ▽ "The Collected Works of Fukui Shizuo 2: The Story of Japanese Battleships II" (2008, Kojinsha)" ▽ "The Collected Works of Fukui Shizuo 6: The Story of World Battleships" (2009, Kojinsha)" ▽ "Tony Gibbons: The Complete Encyclopedia of Battleships and Battlecruisers; A Technical Directory of All The World's Capital Ships from 1860 to Present Day (1983, Salamand Books)”

Battleship Construction (New Jersey)
©Shogakukan ">

Battleship Construction (New Jersey)

History of Battleships (1)
©Shogakukan ">

History of Battleships (1)

History of Battleships (2)
©Shogakukan ">

History of Battleships (2)

History of Battleships (3)
©Shogakukan ">

History of Battleships (3)

Source: Shogakukan Encyclopedia Nipponica About Encyclopedia Nipponica Information | Legend

Japanese:

もっとも強大な砲力と堅牢(けんろう)な防御力を備え、艦隊の主力となり、洋上で砲撃により敵艦船を撃滅することを主任務とした軍艦。多数の大口径砲を搭載し、おおむね自己の主砲弾の命中に耐えるよう、船体主要部の舷側(げんそく)と甲板、主砲塔に厚い甲鈑(こうはん)を装着するとともに、魚雷・機雷の爆発に対する水中防御を有するため船型は大型になり、第二次世界大戦まではわずかな大型航空母艦を除けばもっとも大きな軍艦であった。速力は、同時期の巡洋艦、駆逐艦などの高速艦艇より数ノットないし10ノット程度低い。19世紀後半に出現して以来、第二次世界大戦まで海軍兵力の主力であり、その保有隻数と個艦の威力が国力のシンボルとみなされ、政治・外交に大きな影響を与えたが、第二次世界大戦中に航空機と航空母艦が海軍の主兵力となったため、戦艦は兵術的価値を失い過去の存在となった。大戦後に各国とも順次除籍し、現在は記念保存艦および除籍後の保管艦を除き、すべて姿を消した。

［阿部安雄］

戦艦の沿革

帆船時代

戦艦の起源は17世紀後半に出現した戦列艦ship of the lineに求められる。これは、戦列を構成し、多数の舷側砲の一斉射撃により敵艦隊と交戦することを任務とした木造帆装軍艦で、1805年のトラファルガーの海戦においてイギリス艦隊司令長官ネルソン提督の旗艦となったビクトリーVictory（2162トン、砲100門）は、その代表的なものであった。

［阿部安雄］

装甲艦の誕生から日露戦争まで

19世紀になって蒸気機関の実用化、炸裂(さくれつ)弾を発射する榴弾(りゅうだん)砲の考案などの技術革新が進み、艦砲の威力増大に対応して舷側水線部に厚い甲鈑を張った装甲艦iron cladが建造され、戦列艦にとってかわった。最初の艦は1859年に進水したフランスのグロアールGloire（5600トン、12.8ノット）で、木造船体に厚さ10センチメートルの甲鈑を張り、舷側に16センチ砲30門を装備した機帆兼用艦だった。これに対抗して、1860年に進水したイギリスのウォーリアWarrior（9000トン、14.3ノット、20センチ砲38門）は、初めて船体を鉄製とした装甲艦で、これが戦艦、巡洋戦艦、大型装甲巡洋艦などへと発展した。両艦の出現以後、5000～1万トンで強力な砲兵装を備えた装甲艦が各国で建造され、主砲は装備数を減じて大口径化の途をたどり、初期の舷側砲門艦broadside shipに続いて、船体中央部の防御砲郭に主砲を装備した中央砲郭艦casmate shipが出現し、さらに旋回砲塔を搭載した砲塔艦turret shipが1860年代末につくられた。蒸気機関の発達により帆装は廃止されるようになり、甲板旋回砲塔装備方法の改善が進み、中央の防御区画の上に2基の砲塔を梯形(ていけい)配置した中央砲塔艦central turret shipが1870年代に建造され、さらに船体前部または前後部の中心線上に露砲塔を設けた露砲塔艦barbette shipが1880年代初めに出現した。

　1880年ごろ、従来の前装滑腔(かっくう)砲にかわって元込め式で砲身にライフルを切った後装施条砲が開発され、砲撃威力、命中精度が著しく向上した。1892年に完成したイギリスのロイヤル・ソブリン級Royal Sovereign Class（1万4150トン、16.5ノット）は34センチ後装施条砲4門を露砲塔に装備するとともに、厚さ45.7センチメートルの甲鈑を舷側に装着し、均整のとれた攻防力に加えて優れた航洋力を備え、近代戦艦の嚆矢(こうし)となり、このころから従来の装甲艦、砲塔装甲（甲鉄）艦などにかわって戦艦の名称が使用されるようになった。主砲は、さらに全周囲に耐弾防御を施した砲塔へと発達し、口径は30センチメートルに縮小したが、従来の40～43センチ砲より砲撃威力は増大した。防御甲鈑も滲炭(しんたん)技術を用いて耐弾力を著しく高めたハーベイ甲鈑が発明され、続いてこれを改良したクルップ甲鈑やビッカース甲鈑が開発された。これらの技術進歩を取り入れて1895年に竣工(しゅんこう)したイギリスのマジェスチック級Majestic Class（1万4900トン、17ノット）に至って戦艦の基本形態が定まった。本級は、前後部に30センチ連装砲塔を1基ずつ装備し、以後これが戦艦の標準的主兵装とされ、ド（弩）級戦艦（詳細後述）の出現に至るまでこの方式の艦が各国で多数建造された。三笠(みかさ)（1万5140トン、18ノット、30センチ砲4門）をはじめとする日露戦争時の日本戦艦（すべてイギリス製）もこれに含まれ、いずれも当時の最精鋭艦である。

　当時の砲戦距離はおおむね7000メートル以内であったため、防御は舷側の水線装甲鈑による耐弾防御に重点が置かれ、水中防御はほとんど考慮されていなかった。

［阿部安雄］

日露戦争直後からワシントン会議まで

日露戦争で初めて戦艦どうしの海戦が行われ、大口径砲を搭載した戦艦が海上戦闘の勝敗を決するのに決定的な威力をもち、その集中射撃に対してはいかなる堅艦も抗しえないことが明らかになり、ここに大艦巨砲主義が確立するに至った。イギリスはこの戦訓に基づき、中間砲と15センチ副砲を廃止して極力多数の主砲を搭載し（単一口径主砲主義）、従来の往復動式蒸気機関にかえて蒸気タービンを採用して20ノットを超す速力を実現した、革新的戦艦ドレッドノートDreadnought（1万8110トン、21ノット、30センチ砲連装5基）を1906年に完成させ、これによって従来の戦艦は一挙にその価値を失った。このような単一口径主砲の戦艦を、艦名の最初の文字ドをとってド級戦艦とよんだ。イギリスはドレッドノートと同時に、大型装甲巡洋艦にド級戦艦並みの砲力を搭載し、さらに速力向上を図った巡洋戦艦インビンシブル級Invincible Class（1万7250トン、26.5ノット、30センチ砲8門）を1908年に完成させた。これら両方式の艦が主力艦として各国で競って建造された。

　主砲の口径は30センチから34センチ、36センチ、38センチと増大の一途をたどり、34センチ以上の砲を搭載するものを超ド級艦と称した。主砲の口径増大に対応して防御も強化され、艦型は逐次大型化の道を歩み、第一次世界大戦中には3万トン近い艦も出現した。

　1916年のユトランド沖海戦（ジュットランド海戦ともいう）における戦訓により、大遠距離砲戦での大落角弾に対する甲板防御（水平防御）の強化、至近弾や魚雷の爆発に対する水中防御の強化、弾火薬庫の防炎・防火対策、大浸水や火災に対する応急処置法の開発などが必要とされ、第一次世界大戦末期から戦後にかけてこれらを取り入れた艦が、イギリス、アメリカ、日本で建造され、これをポストジュットランド型と称した。日本の長門(ながと)型（3万3800トン）は防御力の強化のみでなく、主砲に40センチ砲を率先採用し、さらに機関にオールギヤードタービンと重油専焼ボイラーを用いて、26.5ノットの高速戦艦となった。高速戦艦は戦艦の攻防力と巡洋戦艦の速力を兼ね備えたもので、第一次世界大戦中にイギリスが先鞭(せんべん)をつけ、日本の八八艦隊計画の主力艦はすべてこのタイプとして設計された。

［阿部安雄］

ワシントン会議から第二次世界大戦まで

1922年ワシントン海軍軍縮条約の成立により、イギリス、アメリカ、日本、フランス、イタリアの戦艦保有量と新規建造艦の限度（基準排水量3万5000トン以内、主砲口径40センチメートル以下）が定められたことにより、主力艦建造競争に終止符が打たれ、多数の既成艦と未成艦が廃棄された。1927年に完成したイギリスのネルソン級Nelson Class（3万3950トン、23ノット、40センチ砲9門）は条約の規定に従って建造された唯一の戦艦で、徹底した集中防御方式を採用した最初の艦であるとともに、三連装主砲をすべて前部に集中装備し、以後の各国戦艦の設計に大きな影響を及ぼした。

　その後、ドイツの装甲艦ドイッチュラント級Deutschland Class（1万1700トン、26ノット、28センチ砲6門、1933年完成）建造を契機として、ヨーロッパで2万6000～3万2000トン、28～33センチ砲装備の中型高速戦艦が建造された。ついで3万5000トン級で最大口径砲を装備する本格的戦艦の建造が始まり、1936年末に軍縮条約が失効すると、アメリカ、イギリス、日本も新戦艦の建造に着手した。これらは口径36センチメートル以上の大口径砲を搭載し、3万メートル台の優れた大遠距離砲戦能力を備え、重防御の高速戦艦で、高角砲、機銃などの対空兵装を多数装備していた。イギリスのキング・ジョージ5世級King George Ⅴ Class（3万6750トン、27.5ノット、36センチ砲10門）、アメリカのノース・カロライナ級North Carolina Class（3万8000トン、28ノット、40センチ砲9門）、アイオワ級Iowa Class（4万8500トン、33ノット、40センチ砲9門）、日本の大和(やまと)型（6万4000トン、27ノット、46センチ砲9門）などがこの時期の代表的な艦であった。ドイツ、イタリア、フランスも、イギリス、アメリカ艦と同様の高速戦艦を建造し、いずれも第二次世界大戦直前・戦中に完成した。

　航空機と航空母艦の発達により、第二次世界大戦では戦艦部隊どうしの洋上艦隊決戦が行われる機会がなくなり、さらに多数の航空機による集中的な魚雷・爆弾攻撃の前には、いかに強固な防御を施された戦艦といえども耐え抜きえないことが明白に立証されるに至った。この結果、戦艦は長年にわたる海軍主力兵力の地位を失い、第二次世界大戦中は空母機動部隊の直衛、艦隊旗艦、陸上砲撃、船団護衛などに使用された。

［阿部安雄］

現在の戦艦

第二次世界大戦後、各国の戦艦は逐次廃艦とされ、1960年代中ごろまでにアメリカのアイオワ級4隻を残してすべて姿を消した。アメリカは本級を朝鮮戦争およびベトナム戦争で陸上砲撃に用い、さらに1980年代初めから水上打撃部隊の中核艦として使用するため、トマホーク巡航ミサイル、ハープーン対艦ミサイルなどの装備を含む近代化改修工事を実施して再就役させ、このうち2隻は湾岸戦争にも参加した。1990～1992年に4隻とも予備役となり、1995年に除籍され、戦艦の歴史は幕を閉じた。

［阿部安雄］

『『世界の戦艦　大艦巨砲編』（1998・世界文化社）』▽『『世界の戦艦　弩級戦艦編』（1999・世界文化社）』▽『『世界の戦艦――砲力と装甲の優越で艦隊決戦に君臨したバトルシップ発達史　「歴史群像」太平洋戦史シリーズ41』（2003・学習研究社）』▽『『世界の艦船増刊第83集　近代戦艦史』（2008・海人社）』▽『『福井静夫著作集1　日本戦艦物語Ⅰ』（2008・光人社）』▽『『福井静夫著作集2　日本戦艦物語Ⅱ』（2008・光人社）』▽『『福井静夫著作集6　世界戦艦物語』（2009・光人社）』▽『Tony GibbonsThe Complete Encyclopedia of Battleships and Battlecruisers; A Technical Directory of All The World's Capital Ships from 1860 to Present Day（1983, Salamand Books）』