:: wikimiki.org ::
| WWI |
WWI
, and the use of new, devastating weapons - tanks, aircraft, machine guns, and poison gas.]]
World War I, also known as the First World War, the Great War, the War of the Nations and the War to End All Wars, was a world conflict lasting from 1914 to 1919, with the fighting lasting until 1918. The label World War I or First World War did not come into general use until after the outbreak of World War II in 1939, and until then it was known as the Great War or the World War. The war was fought by the Allied Powers on one side, and the Central Powers on the other. No previous conflict had mobilized so many soldiers or involved so many in the field of battle. By its end, the war had become the second bloodiest conflict in recorded history (behind the Taiping Rebellion), though it was surpassed within a generation by World War II.
World War I became infamous for trench warfare; this was especially true of the Western Front. The trenches went from the North Sea to the border of Switzerland in Europe. More than 9 million died on the war's battlefields, and nearly that many more on the home fronts because of food shortages, genocide, and ground combat. Among other notable events, the first large-scale bombing from the air was undertaken and some of the century's first large-scale civilian massacres took place, as one of the aspects of modern efficient, non-chivalrous warfare. In the First World War 5% of casualties were civilian. In the Second World War that was 50%.
World War I proved to be the decisive break with the old world order, marking the final demise of absolutist monarchy in Europe. Four empires were shattered: the German, the Austro-Hungarian, the Ottoman, and the Russian. Their four dynasties, the Hohenzollerns, the Habsburgs, the Ottomans, and the Romanovs, who had roots of power back to the days of the Crusades, all fell during or after the war.
The post-war failure to deal effectively with many of the causes and results of the War would lead to the rise of Fascism in Italy, Nazism in Germany and the outbreak of World War II within a generation. The War was the catalyst for the Bolshevik Russian Revolution, which would inspire later Communist revolutions in countries as diverse as China and Cuba, and would lay the basis for the Cold War standoff between the Soviet Union and the United States. In the east, the demise of the Ottoman Empire paved the way for a modern democratic successor state, Turkey. In Central Europe, new states such as Czechoslovakia and Yugoslavia were born and Poland was re-created.
__TOC__
Causes
Poland of Franz Ferdinand. The murder was the igniting torch of World War I.]]
:See also: Causes of World War I and Participants in World War I
On June 28, 1914, Franz Ferdinand, Archduke of Austria and heir to the Austro-Hungarian throne, was assassinated in Sarajevo by Gavrilo Princip, a Bosnian Serb student. He was part of a group of fifteen assassins, acting with support from the Black Hand, a secret society founded by pan-Serbian nationalists, with links to the Serbian military. The assassination sparked little initial concern in Europe. The Archduke himself was not popular, least of all in the Austro-Hungarian Empire. While there were riots in Sarajevo following the Archduke's death, these were largely aimed at the Serbian minority. Though this assassination has been linked as the direct trigger for World War I, the war's real origins lie further back, in the complex web of alliances and counterbalances that developed between the various European powers after the defeat of France and formation of the German state under the leadership of Otto von Bismarck in 1871.
Reasons & Responsibilities
- See also: Causes of World War I
There are many different hypotheses that try to explain who, or what, is to blame for the outbreak of the First World War. Early explanations, prominent in the 1920s and 1930s, stressed the official version of responsibility as described in the Treaty of Versailles and Treaty of Trianon, that Germany and its allies were solely responsible for the war. However, as time progressed, scholars began looking toward the rigidity of both German and Russian military planning, each of which stressed the importance of striking first and executing plans quickly.
The fact that for many decades the British had been accustomed to colonial wars which were won relatively easily against much weaker adversaries certainly helped build enthusiasm for the Great war. In addition, the fact that no major political force opposed the war meant that those who did not agree with it had little organisational power to build opposition, though small protests continued throughout the war.
Another cause of the war was the building of alliances and arms races. An example of the latter is the launch of HMS Dreadnought, a revolutionary battleship that rendered all previous ships obsolete as "pre-dreadnoughts", in 1906. This weakened Britain's power as a seafaring nation and sparked a major naval arms race in shipbuilding, particularly between Britain and Germany due to new imperialism. Overall, nations in the Triple Entente became fearful of the Triple Alliance and vice versa.
The civilian leaders of the European powers also found themselves facing a wave of nationalist zeal that had been building across Europe for years. This left governments with ever fewer options and little room to manoeuvre as the last weeks of July 1914 slipped away. Frantic diplomatic efforts to mediate the Austrian-Serbian quarrel simply became irrelevant, as the automatic military escalations between Germany and Russia reinforced one another.
Furthermore, the problem of communications in 1914 should not be underestimated; all nations still used telegraphy and ambassadors as the main form of communication, resulting in delays from hours to even days.
There is probably no single concise or conclusive assessment of the exact cause of the First World War.
Outbreak of war
ambassadors are depicted in green, the Central Powers in red, and neutral countries in yellow.]]
Austria–Hungary was created in the "Ausgleich of 1867" after Austria was defeated by Prussia. As agreed in 1867, the Habsburgs were the Emperors of the Austrian Empire. With the formation of the Dual Monarchy, Franz Josef became leader of a nation with sixteen ethnic groups and five major religions speaking no fewer than nine languages.
In large measure because of the vast disparities that existed within the Empire, Austrians and Hungarians always viewed growing Slavic nationalism with deep suspicion and concern. Thus the Austro-Hungarian government grew worried with the near-doubling in size of neighbouring Serbia's territory as a result of the Balkan Wars of 1912–1913. Serbia, for its part, made no qualms about the fact that it viewed all of Southern Austria–Hungary as part of a future Great South Slavic Union. This view had also garnered considerable support in Russia. Many in the Austrian leadership, not least Habsburg Emperor Franz Joseph, and Conrad von Hötzendorf, worried that Serbian nationalist agitation in the southern provinces of the Empire would lead to further unrest among the Austro-Hungarian Empire's other disparate ethnic groups. The Austro-Hungarian government worried that a nationalist Russia would back Serbia to annex Slavic areas of Austria–Hungary. The feeling was that it was better to destroy Serbia before they were given the opportunity to launch a campaign.
After the assassination of Franz Ferdinand by Gavrilo Princip and nearly a month of debate the government of Austria–Hungary sent a 10-point ultimatum to Serbia (July 23, 1914) — the so called July Ultimatum — to be unconditionally accepted within 48 hours. The ultimatum was the first of a series of diplomatic events known as the July Crisis which set off a chain reaction and a general war in Europe.
The Serbian government agreed to all but one of the demands in the ultimatum, noting that participation in its judicial proceedings by a foreign power would violate its constitution. Austria–Hungary nonetheless broke off diplomatic relations (July 25) and declared war (July 28) through a telegram sent to the Serbian government.
The Russian government, which had pledged in 1909 to uphold Serbian independence in return for Serbia's acceptance of the Bosnia annexation, mobilised its military reserves on 30 July following a breakdown in crucial telegram communications between Kaiser Wilhelm and Tsar Nicholas II (the famous "Willy and Nicky" correspondence), who was under pressure by his military staff to prepare for war. Germany demanded (31 July) that Russia stand down its forces, but the Russian government persisted, as demobilization would have made it impossible to re-activate its military schedule in the short term. Germany declared war against Russia on August 1 and, two days later, against the latter's ally France.
The outbreak of the conflict is often attributed to the alliances established over the previous decades — Germany-Austria-Italy vs France-Russia; Britain and Serbia being aligned with the latter. In fact, none of the alliances were activated in the initial outbreak, though Russian general mobilization and Germany's declaration of war against France were motivated by fear of the opposing alliance being brought into play.
Britain declared war against Germany on August 4. This was ostensibly provoked by Germany's invasion of Belgium on August 4 1914, whose independence Britain had guaranteed to uphold in the Treaty of London of 1839, and which stood astride the planned German route for invasion of Russia's ally France. Unofficially, it was already generally accepted in government that Britain could not remain neutral, since without the co-operation of France and Russia its colonies in Africa and India would be under threat, while German occupation of the French Atlantic ports would be an even larger threat to British trade as a whole.
The spread of war
;1914
- July 23: Austria-Hungary ultimatum to Serbia.
- July 28: Austria-Hungary declares war on Serbia.
- July 31: Russia begins mobilization.
- August 1: Germany declares war on Russia.
- August 2: German troops occupy Luxembourg.
- August 3: Germany declares war on France.
- August 4: Germany invades neutral Belgium; the United Kingdom declares war on Germany in response.
- August 6: Montenegro sides with its traditional ally, Serbia, and declares war on Austria-Hungary.
- August 10: Austria-Hungary declares war on Russia.
- August 12: The United Kingdom and France declare war on Austria-Hungary.
- August 23: Japan declares war on Germany.
- September: Unity Pact signed by France, Britain, and Russia.
- October 9: Belgium falls to German troops at the Siege of Antwerp.
- October 29: The Ottoman Empire enters the war on the side of Germany and Austria-Hungary.
- November 2: Russia declares war on the Ottoman sultanate.
- November 5: France and United Kingdom declare war on the Ottoman sultanate.
- December 25: Christmas Truce in the Trenches.
;1915
- April 25: Gallipoli campaign commences. Turks defeat Allies crushingly.
- April 26: Italy secretly signs the London Pact with the Triple Entente.
- May 23: Italy declares war on Austria-Hungary.
- October 14: Bulgaria declares war on Serbia and enters the war on the side of Germany and Austria-Hungary.
;1916
- March 9: Germany declares war on Portugal (see Portugal in the Great War).
- August 27: Romania declares war on Austria-Hungary.
- August 28: Italy declares war on Germany.
;1917
- January 16: Germany sends the Zimmermann Telegram to Mexico, proposing an alliance against the United States.
- April 6: The United States declares war on Germany.
- June 27: Greece enters the war on the side of the Entente.
- July 6: Arab Revolt troops under Lawrence Of Arabia capture Aqaba, a main sea port for the Ottoman Empire.
- August 14: The Republic of China declares war on Germany.
- October 26: Brazil declares war on Germany.
- November 7: The October Revolution takes place in Russia.
- December 7: United States declares war on Austria-Hungary.
;1918
- January 8: President Woodrow Wilson made his famous Fourteen Points address, introducing the idea of a League of Nations.
- 3 March: Russia and the Central Powers sign the Treaty of Brest-Litovsk, marking Russia's exit from World War I.
- October 30: Mudros/Turkish Armistice signed opening Turkish territory to Entente military operations.
- November 11: Armistice signed, end of World War I.
;1919
- 28 June: Treaty of Versailles, official end to World War I between the Entente and Germany.
;1920
- 4 June: Treaty of Trianon, partition of Austro-Hungarian Empire's Kingdom of Hungary.
;1923
- 24 July: Treaty of Lausanne, peace made with Turkey.
- 29 October: Turkey changes its government to republic.
Opening battles
republic
Some of the very first actions of the war occurred far from Europe, in Africa and in the Pacific Ocean. On August 8 1914 a combined French and British Empire force invaded the German protectorate of Togoland. On August 10 German forces based in South-West Africa attacked South Africa. New Zealand occupied German Samoa (30 August 1914) and on September 11 the Australian Naval and Military Expeditionary Force landed on the island of Neu Pommern, which formed part of German New Guinea. Within a few months the Entente forces had accepted the surrender of or driven out German forces in the Pacific. Sporadic and fierce fighting continued in Africa for the remainder of the war.
In Europe, Germany and Austria-Hungary suffered from miscommunication regarding each army's intentions. Germany had originally guaranteed to support Austria-Hungary's invasion of Serbia, but the interpretations of this idea differed. Austro-Hungarian leaders thought Germany would cover her northern flank against Russia, but Germany had planned for Austria-Hungary to focus the majority of its troops on Russia while Germany dealt with France on the Western Front. This confusion forced the Austro-Hungarian army to split its troop concentrations from the south in order to meet the Russians in the north. The Serb army, coming up from the south of the country, met the Austrian army at the Battle of Cer on 12 August 1914.
The Serbians occupied defensive positions against the Austrians. The first attack came on August 16th, between parts of the 21st Austro–Hungarian division and parts of the Serbian Combined division. In harsh night-time fighting the battle ebbed and flowed, until Stepa Stepanovic rallied the Serbian line. Three days later the Austrians retreated across the Danube, having suffered 21,000 casualties as against 16,000 Serbian. This marked the first major Allied victory of the war. The Austrians had not achieved their main goal of eliminating Serbia, and it became increasingly likely that Germany would have to maintain forces on two fronts.
Germany's plan (named the Schlieffen plan) to deal with the Franco-Russian alliance involved delivering a knock-out blow to the French and then turning to deal with the more slowly mobilized Russian army. Rather than invading eastern France directly, German planners deemed it prudent to attack France from the north. To do so, the German army had to march through Belgium. Germany demanded free passage from the Belgian government, promising to treat Belgium as Germany's firm ally if the Belgians agreed. When Belgium refused, Germany invaded and began marching through Belgium anyway, after first invading and securing Luxembourg. It soon encountered resistance before the forts of the Belgian city of Liège, although the army as a whole continued to make rapid progress into France. Britain sent an army to France (the British Expeditionary Force, or BEF), which advanced into Belgium. Initially the Germans had great successes in the Battle of the Frontiers (14–24 August 1914).
However, the delays brought about by the resistance of the Belgian, French and British forces; the unexpectedly rapid mobilization of the Russians; and the overly-ambitious objectives upset the German plans. Russia attacked in East Prussia, diverting German forces intended for the Western Front. Germany defeated Russia in a series of battles collectively known as the Second Battle of Tannenberg (17 August – 2 September). This diversion exacerbated problems of insufficient speed of advance from railheads, not allowed for by the German General Staff, and allowed French and British forces to finally halt the German advance on Paris at the First Battle of the Marne (September 1914) as the Entente forced the Central Powers into fighting a war on two fronts. The German army had fought its way into a good defensive position inside France and had permanently incapacitated 230,000 more French and British troops than it had lost itself in the months of August and September. Yet staff incompetence and leadership timidity, as Ludendorff had needlessly transferred troops from the right to protect Sedan, cost Germany the chance for an early knockout.
Early stages: from romanticism to the trenches
Sedan, 1917]]
The perception of war in 1914 was romanticized by many people, and its declaration was met with great enthusiasm by these people. The common view was that it would be a short war of manoeuvre with a few sharp actions (to "teach the enemy a lesson") and would end with a victorious entry into the enemy capital, then home for a victory parade or two and back to "normal" life. However, many people regarded the coming war with great pessimism and worry. Many military figures, such as Lord Kitchener and Erich Ludendorff, predicted the war would be a long one. Other political leaders, such as Bethmann Hollweg in Germany, were concerned by the potential social consequences of a war. International bond and financial markets entered severe crises in late July and early August reflecting worry about the financial consequences of war.
The perceived excitement of war captured the imagination of many in the warring nations. Spurred on by propaganda and nationalist fervor, many eagerly joined the ranks in search of adventure. Few were prepared for what they actually encountered at the front.
See also: Recruitment to the British Army during WW I
Trench warfare begins
:Main article: Western Front (World War I)
Advances in military technology meant that defensive firepower out-weighed offensive capabilities, making the war particularly murderous, as tactics had failed to keep up. Barbed wire was a significant hindrance to massed infantry advances; artillery, now vastly more lethal than in the 1870s, coupled with machineguns, made crossing open ground a nightmarish prospect. General Staffs of European armies had uniformly ignored the lessons of the U.S. Civil War and were often indifferent to massive loss of life (General Haig's diaries are particularly striking in this respect).
After their initial success on the Marne, Entente and German forces began a series of outflanking manoeuvres to try to force the other to retreat, in the so-called Race to the Sea. Britain and France soon found themselves facing entrenched German positions from Lorraine to Belgium's Flemish coast. Britain and France sought to take the offensive while Germany defended occupied territories. One consequence was that German trenches were much better constructed than those of their enemy: Anglo-French trenches were only intended to be 'temporary' before their forces broke through German defences. Some hoped to break the stalemate by utilizing science and technology. In April 1915, the Germans used mustard gas for the first time, opening a four mile wide hole in the Allied lines when French colonial troops retreated before it. This breach was closed by Canadian soldiers at Ypres, earning German respect. Neither side proved able to deliver a decisive blow for the next four years, though protracted German action at Verdun throughout 1916, and the Entente's failure at the Somme in the summer of 1916 brought the French army to the brink of collapse. Futile attempts at more frontal assaults, at terrible cost to the French poilu (infantry), led to mutinies which threatened the integrity of the front line after the Nivelle Offensive in spring of 1917. News of the Russian Revolution gave a new incentive to socialist sentiments. Red flags were hoisted and the Internationale was sung on several occasions. At the height of the mutiny, 30,000 to 40,000 French soldiers participated. Throughout 1915-17 the British Empire and France suffered many more casualties than Germany, but both sides lost millions of soldiers to injury and disease.
Around 800,000 soldiers from the British Empire were on the Western Front at any one time, 1,000 battalions each occupying a sector of the line from Belgium to the Arne and operating a month-long four stage system, unless an offensive was underway. The front contained over 6,000 miles of trenches. Each battalion held its sector for around a week before moving back to support lines and then the reserve lines before a week out-of-line, often in the Poperinge or Amiens areas.
Southern theatres
Entry of the Ottoman Empire
The Ottoman Empire joined the Central Powers in October–November 1914, due to the secret Turko-German Alliance signed on August 2, 1914, threatening Russia's Caucasian territories and Britain's communications with India and the East via the Suez canal. British Empire action opened another front in the South with the Gallipoli (1915) and Mesopotamian campaigns, though initially the Turks were successful in repelling enemy incursion. In Mesopotamia, by contrast, after the disastrous Siege of Kut (1915–16), British Empire forces reorganized and captured Baghdad in March 1917. Further to the west in the Sinai and Palestine Campaign, initial British failures were overcome with Jerusalem being captured in December 1917 and the Egyptian Expeditionary Force under Edmund Allenby going on to break the Ottoman forces at the Battle of Megiddo (September 1918).
Russian armies generally had the best of it in the Caucasus. Enver Pasha, supreme commander of the Turkish armed forces, was a very ambitious man, with a dream to conquer central Asia. He was not a practical soldier. He launched an offensive with 100,000 troops against the Russians in the Caucasus in December of 1914. Insisting on a frontal attack against Russian positions in the mountains in the heart of winter, Enver lost 86% of his force. A new Russian commander on the front in the fall of 1915, Grand Duke Nicholas, brought new vigour. A major offensive in 1916 drove the Turks out of much of present-day Armenia, and tragically provided a context for the deportation and genocide against the Armenian population in eastern Armenia. With control of part of the southern Black Sea coast, Nicholas pushed forward the construction of railway lines to bring up supplies. He was ready for an offensive in the spring of 1917. If it had gone ahead, there was a very good chance that Turkey would have been knocked out of the war in the summer of 1917. But, because of the Russian Revolution, Grand Duke Nicholas was recalled and the Russian armies soon fell apart.
Italian participation
:Main article: Italian Campaign (WWI)
Italy had been allied to the German and Austro-Hungarian Empires since 1882, but had its own designs against Austrian territory in the Trentino, Istria and Dalmatia, and a secret 1902 understanding with France effectively nullifying its alliance commitments. Italy refused to join Germany and Austria-Hungary at the beginning of the war, because the alliance was defensive, while Austria declared war on Serbia. The Austrian government started negotiations to obtain Italian neutrality in exchange for French territories (Tunisia), but Italy joined the Entente by signing the London Pact in April and declaring war on Austria-Hungary in May 1915; it declared war against Germany fifteen months later.
In general, the Italians enjoyed numerical superiority, but were poorly equipped; instead, the Austro-Hungarian defence took advantage of the elevation of their bases in the mostly mountainous terrain, which was anything but suitable for military offensives. For the most part the front remained unchanged during the war, while Austrian Kaiserschützen and Standschützen and Italian Alpini fought bitter close combat battles during summer and tried to survive during winter in the high mountains.
Beginning in 1915, the Italians mounted 17 major offensives on the Isonzo front (the part of the border nearest Trieste), all repelled by the Austro-Hungarians, who had the higher ground. The Austro-Hungarians counter-attacked from the Altopiano of Asiago towards Verona and Padua in the spring of 1916 (Strafexpedition), but they also made little progress. In the summer, the Italians took back the initiative, capturing the town of Gorizia. After this minor victory, the front remained practically stable for over one year, despite several Italian offensives, again all on the Isonzo front. In the fall of 1917, thanks to the improving situation on the Eastern front, the Austrians received large reinforcements, including German assault troops. On October 26, they launched a crushing offensive that resulted in the victory of Caporetto: the Italian army was routed, but after retreating more than 100km, it was able to reorganize and hold at the Battle of the Piave River. In 1918 the Austrians repeatedly failed to break the Italian line, and, decisively defeated in the Battle of Vittorio Veneto, surrendered to the Entente powers in November.
Throughout the war Austro-Hungarian Chief of Staff, Conrad von Hötzendorf had a deep hatred for the Italians because he had always perceived them to be the greatest threat to his state. Their betrayal in 1915 enraged him even further. His hatred for Italy blinded him in many ways, and he made many foolish tactical and strategic errors during the campaigns in Italy.
The War in the Balkans
After repelling three Austrian invasions in August-December 1914, Serbia fell to combined German, Austrian and Bulgarian invasion in October 1915. The Serbian army retreated into Albania and Greece. In late 1915, a Franco-British force landed at Salonica in Greece to offer assistance and to pressure the Greek government into war against the Central Powers. Unfortunately for the Allies, the pro-allied government of Eleftherios Venizelos fell before the allied expeditionary force even arrived, and the pro-German king, Constantine, prevented official Greek entry into the war for two years, until 1917. Meanwhile, the Salonica Front proved entirely immobile, so that it was joked that Salonica was the largest German prisoner of war camp. Only at the very end of the war, after most of the German and Austro-Hungarian troops had been removed and the front had to be held by the Bulgarians alone, were the Entente powers able to make a breakthrough, leading to Bulgaria's signing an armistice on September 29, 1918.
The Eastern Front
1918
:Main article: Eastern Front (World War I)
While the Western Front had reached stalemate in the trenches, the war continued in the east. The Russian initial plans for war had called for simultaneous invasions of Austrian Galicia and German East Prussia. Although Russia's initial advance into Galicia was largely successful, they were driven back from East Prussia by the victories of the German generals Hindenburg and Ludendorff at Tannenberg and the Masurian Lakes in August and September 1914. Russia's less-developed economic and military organization soon proved unequal to the combined might of the German and Austro-Hungarian Empires. In the spring of 1915 the Russians were driven back in Galicia, and in May the Central Powers achieved a remarkable breakthrough on Poland's southern fringes, capturing Warsaw on August 5 and forcing the Russians to withdraw from all of Poland, known as the "Great Retreat".
The Russian Revolution
Dissatisfaction with the Russian government's conduct of the war grew despite the success of the June 1916 Brusilov offensive in eastern Galicia against the Austrians, when Russian success was undermined by the reluctance of other generals to commit their forces in support of the victorious sector commander. Allied fortunes revived only temporarily with Romania's entry into the war on August 27: German forces came to the aid of embattled Austrian units in Transylvania, and Bucharest fell to the Central Powers on December 6. Meanwhile, internal unrest grew in Russia, as the Tsar remained out of touch at the front, while Empress Alexandra's increasingly incompetent rule drew protests from all segments of Russian political life, resulting in the murder of Alexandra's favourite Rasputin by conservative noblemen at the end of 1916.
conservative]
In March 1917, demonstrations in St. Petersburg culminated in the abdication of Tsar Nicholas II and the appointment of a weak centrist Provisional Government, which shared power with the socialists of the Petrograd Soviet. This division of power led to confusion and chaos, both on the front and at home, and the army became progressively less able to effectively resist Germany. Meanwhile, the war, and the government, became more and more unpopular, and the discontent led to a rise in popularity of the Bolshevik party, led by Vladimir Lenin, who were then able to gain power.
The triumph of the Bolsheviks in November was followed in December by an armistice and negotiations with Germany. At first, the Bolsheviks refused to agree to the harsh German terms, but when Germany resumed the war and marched with impunity across Ukraine, the new government acceded to the Treaty of Brest-Litovsk on March 3, 1918, which took Russia out of the war and ceded vast territories including Finland, the Baltic provinces, Poland and Ukraine to the Central Powers.
After the Russians initially dropped out of the war, Entente led a small-scale invasion of Russia. The invasion was made with intent to punish the Russians for dropping out of World War I and to support the Tsarists in the Russian Revolution. Troops landed in Archangel and in Vladivostok. The Entente forces were initially told they were invading to defend supplies from German troops. In reality, they were defending them from communist Russians. A memorial commemorating the event is located in White Chapel Cemetery in Troy, Michigan. The force also included a number of Canadians who were based in Vladivostok. The Canadian force contained an artillery unit, but they saw minimal combat.
The Last Half
Troy, Michigan
Events of 1917 would prove decisive in ending the war, although their effects would not fully be felt until 1918. The Entente's naval blockade of Germany began to have serious impact on morale and productivity on the German home-front. In response, in February 1917, the German General Staff (OHL) were able to convince Chancellor Theobald von Bethmann-Hollweg to declare unrestricted submarine warfare, with the goal of starving Britain out of the war. Tonnage sunk rose above 500,000 tons per month from February until July, peaking at 860,000 tonnes in April. After July, the newly introduced convoy system was extremely effective in neutralizing the U-boat threat. Britain was safe from the threat of starvation.
The decisive victory of Germany at the Battle of Caporetto led to the Entente decision at the Rapallo Conference to form the Supreme Allied Council at Versailles to co-ordinate plans and action. Previously British Empire and French armies had operated under separate command systems.
In December, the Central Powers signed an Armistice with Russia, thereby releasing troops from the eastern front for use in the west. Ironically, German troop transfers could have been greater if their territorial acquisitions had not been so dramatic. With both German reinforcements and new American troops pouring into the Western Front, the final outcome of the war was to be decided in that front. The Central Powers knew that they could not win a protracted war now that American forces were certain to be arriving in increasing numbers, but held high hopes for a rapid offensive in the West, using their reinforced troops and new infantry tactics. Furthermore, rulers of both the Central Powers and the Entente became more fearful of the threat first raised by Ivan Bloch in 1899, that protracted industrialized war threatened social collapse and revolution throughout Europe. Both sides urgently sought a decisive, rapid victory on the Western Front as they were both fearful of collapse or stalemate.
Entry of the United States
revolution
A long stretch of American isolationism (the Monroe Doctrine) left the United States reluctant to involve itself with what was popularly conceived as a European dispute.
Early in 1917 Germany resumed its policy of unrestricted submarine warfare. This, combined with public indignation over the Zimmermann telegram, led to a final break of relations with the Central Powers. President Woodrow Wilson requested that the U.S. Congress declare war on Germany, which it did on April 6, 1917 (see: Woodrow Wilson declares war on Germany on Wikisource). The Senate approved the war resolution 82-6, the House with 373-50. Wilson hoped a separate peace could be achieved with Austria-Hungary; however, when it kept its loyalty to Germany, the US declared war on Austria-Hungary in December 1917.
Although the American contribution to the war was important, particularly in terms of the threat posed by increased US presence in Europe, the United States was never formally a member of the Entente, but an "Associated Power". Significant numbers of American troops only arrived in Europe in the summer of 1918.
Still, the United States had been in a state of full miltitary-related production, aiding the Entente for quite some time. This was another reason for the decision to resume unrestricted submarine warfare, as America's declaration of war would only change circumstances once troops began to arrive in Europe in the distant future. However, the United States Army and the National Guard had mobilized in 1916 to pursue the Mexican "bandit" Pancho Villa, aiding the speed of wartime mobilization after April, 6, 1917. The German High Command saw the episode as reconfirming evidence of American military incompetence.
The United States Navy was able to send a battleship group to Scapa Flow to join with the British Grand Fleet, a number of destroyers to Queenstown, Ireland and several divisions of submarines to the Azores and Bantry Bay, Ireland to help guard convoys. However, it would be some time before the United States forces would be able to contribute significant manpower to the Western and Italian fronts.
The British and French insisted that the United States emphasize sending infantry to reinforce the line. Throughout the war, the American forces were short of their own artillery, aviation, and engineering units. However, General John J. Pershing, American Expeditionary Force commander, resisted breaking up American units and using them as reinforcements for British Empire and French units, as suggested by the Allies. Pershing also maintained the use of frontal assaults, which had been discarded by that time by British Empire and French commanders. As a result the American Expeditionary Force suffered a very high rate of casualties in its operations in the summer and fall of 1918.
German Spring Offensive of 1918
American Expeditionary Force]
Ludendorff made plans for a 1918 general offensive along the Western Front, codenamed Operation Michael. The Spring Offensive sought to divide the British Empire and French armies in a series of feints and advances. The German leadership hoped to strike a decisive blow before the United States forces could be deployed. Before the offensives even began, Ludendorff may have made the mistake of leaving the elite Eighth Army in Russia and sending over only a small portion of the forces from the east to aid the offensive in the west.
Operation Michael opened on 21 March, 1918 with an attack against British Empire forces, towards the rail junction at Amiens. It was Ludendorff's intention to split the British Empire and French armies at this point. German forces achieved an unprecedented advance of 60 km. For the first time since 1914, manoeuvre had returned to the battlefield.
British and French trenches were defeated using novel infiltration tactics. To this time, attacks had been characterized by long artillery bombardments and continuous-front mass assaults. However, in the Spring Offensive the German Army used artillery briefly and infiltrated small groups of infantry at weak points, attacking command and logistics areas and surrounding points of serious resistance. These isolated positions were then destroyed by more heavily armed infantry. German success relied greatly on this tactic.
The front line had now moved to within 120 kilometres of Paris. Three super-heavy Krupp railway guns advanced to fire 183 shells on Paris, causing many Parisians to flee the city. The initial stages of the offensive were so successful that
Tank: This article is about armoured fighting vehicles. For other meanings, see Tank (disambiguation).
Tank (disambiguation)
A tank is a tracked, armoured combat vehicle (armoured fighting vehicle), designed primarily to engage enemy forces by the use of direct fire. A modern main battle tank is distinguished by its high level of firepower, mobility and armour protection relative to other vehicles of its era. It can cross comparatively rough terrain at high speeds, but is fuel, maintenance, and ammunition-hungry and is logistically demanding. It has the heaviest armour of any vehicle on the battlefield, and carries a powerful weapon able to engage a wide variety of ground targets. It is among the most versatile and fearsome weapons on the battlefield, valued for its shock action against other troops and high survivability.
Tank organisations (or armoured units) are usually employed with infantry in combined arms warfare, supported by engineers, artillery, aircraft, and other support arms. If not properly protected, tanks can be vulnerable to attack by infantry, mines, artillery, and aircraft strikes.
Tanks were first used in the First World War, to break the deadlock of the trenches, and they evolved to take the role of cavalry on the battlefield. The name tank first arose in British factories making the hulls of the first battle tanks: the workmen were given the impression they were constructing tracked water containers for the British Army, hence keeping the production of a fighting vehicle secret.
Tanks and tank tactics have undergone many generations of evolution over nearly a century. Although weapons systems and armour continue to be developed, many nations have been reconsidering the need for such heavy weaponry in a period characterised by unconventional warfare.
History
: Main article: History of the tank
World War One: the first tanks
Having already seen Rolls Royce armoured cars used by Royal Naval Air Service in 1914, and aware of schemes to create a tracked fighting vehicle, First Lord of the Admiralty Winston Churchill sponsored the Landships Committee to oversee development of this new weapon. The first successful prototype tank, nicknamed Little Willie, was tested for the British Army on September 6, 1915. Although initially termed landships by the Admiralty, the initial vehicles were colloquially referred to as water-carriers, later shortened to tanks, to preserve secrecy. The word tank was used to give the workers the impression they were constructing tracked water containers for the British army in Mesopotamia, and it was made official on December 24, 1915.
1915The first tank became operational when Captain H. W. Mortimore of the Royal Navy took a Mark I into action at Delville Wood during the Battle of the Somme on September 15 1916. The French developed the Schneider CA1 working from Holt caterpillar tractors, and first used it on April 16 1917. The first successful use of massed tanks in combat occurred at the Battle of Cambrai on November 20, 1917.
The tank would eventually make trench warfare obsolete, and the thousands of tanks fielded during the war by French and British forces made a significant contribution. Initial results with tanks were mixed, with problems in reliability (and impatience high command) causing considerable attrition in combat. Deployment in small groups also lessened their tactical value and impact, which was at first formidable. German forces suffered from shock and lacked counter-weapons, though they did (accidentally) discover solid anti-tank shot, and used of wider trenches to limit the British tanks' mobility. This and unreliability forced Allied tanks to continue evolving for the duration of the war, including models such as the very long Mark V (which could navigate large obstacles, especially wide trenches, more easily than many modern AFVs), while Germany mostly fielded a small number of captured tanks, and only made twenty of their native design, the A7V. Demands from infantry to have tanks close by would have pernicious effects on British tank design and tactics well into WW2.
1920s to the end of Second World War
With the tank concept now established, several nations designed and built tanks between the two world wars. The British designs were the most advanced, due largely to their successes in WWI, to the state of the other European powers France and Germany, and the detachment of the USA.
Throughout this period several classes of tanks were common, most of this development taking place in the UK. Light tanks, typically weighing ten tons or less, were used primarily for scouting and generally mounted a light gun that was useful only against other light tanks. The medium (or cruiser tanks as they were known in the UK) were somewhat heavier and focussed on long-range high-speed travel. Finally, the heavy or infantry tanks were heavily armoured and generally very slow. The overall idea was to use infantry tanks in close concert with infantry to effect a breakthrough, their heavy armour allowing them to survive with enemy antitank weapons. Once this combined force broke the enemy lines, groups of cruiser tanks would be sent through the gap, operating far behind the lines to attack supply lines and command units. This one-two punch was the basic combat philosophy of the British tank formations, and was adopted by the Germans as a major component of the blitzkrieg concept. J.F.C. Fuller's doctrine of WWI was the fount for work by all the main pioneers: Hobart in Britain, Guderian in Germany, Chaffee in the U.S., de Gaulle in France, and Tukhachevsky in the USSR. All came to roughly the same conclusions, Tukhachevsky's integration of airborne pathfinders arguably the most sophisticated; only Germany would actually put the theory to practise, and it was their superior tactics, not superior weapons, that made blitzkrieg so formidable.
There was thought put into tank-against-tank combat, but the focus was on powerful antitank guns and similar weapons, including dedicated antitank vehicles. This achieved its fullest expression in the United States, where tanks were expected to avoid enemy armour, and let dedicated tank destroyer units deal with them. Britain took the same path, and both produced light tanks in the hope that with speed, they could avoid being hit, comparing tanks to ducks. In practice these concepts proved dangerous. As the numbers of tanks on the battlefield increased, the chance of meetings grew to the point where all had to be an effective antitank vehicle as well; moreover, tanks designed to cope only with other tanks were helpless against antitank guns. This led to a rapid up-armouring and up-gunning of almost all tank designs. Tank shape, previously guided purely by considerations of obstacle clearance, now became a trade-off, with a low profile desirable for stealth and stability.
World War II saw a series of advances in tank design. Germany for example, initially fielded lightly armoured and lightly armed tanks, such as the Panzer I, which had been intended for training use only. These fast-moving tanks and other armoured vehicles were a critical element of the Blitzkrieg. However, they fared poorly in direct combat with British tanks and suffered severely against the Soviet T-34, which was superior in armour and weaponry. By the end of the war all forces had dramatically increased their tanks' firepower and armour; for instance, the Panzer I had only two machine guns, and the Panzer IV, the "heaviest" early war German design, carried a low-velocity 75mm gun and weighed under twenty tonnes. By the end of the war the standard German medium tank, the Panther, mounted a powerful, high-velocity 75mm gun and weighed forty-five tonnes.
Another major wartime advance was the introduction of radically improved suspension systems. Although this might not sound important, the quality of the suspension is the primary determinant of a tank's cross-country performance. Tanks with limited suspension travel subject their crew to massive shaking, making operation difficult, limiting speed, and making firing on the move practically impossible. Newer systems like the Christie or torsion bar suspension dramatically improved performance, allowing the late-war Panther to travel cross country at speeds that would have been difficult for earlier designs to reach on pavement.
By this time most tanks were equipped with radios (all U.S. and German, some Soviet; British radios were common, but often of indifferent quality), vastly improving the direction of units. Tank chassis were adapted to a wide range of military jobs, including mine-clearing and combat engineering tasks. All major combatant powers also developed specialised self-propelled guns: artillery, tank destroyers, and assault guns (armoured vehicles carrying large-calibre guns). German and Soviet assault guns, simpler and cheaper than tanks, had the heaviest guns in any vehicles of the war, while American and British tank destroyers were scarcely distinguishable (except in doctrine) from tanks.
Turrets, which were not previously a universal feature on tanks, were recognised as the way forward. It was appreciated that if the tank's gun was to be used to engage armoured targets then it needed to be as large and powerful as possible, making having one large gun with an all-round field of fire vital. Multiple-turreted tank designs like the Soviet T-35 were abandoned by World War II. Most tanks retained at least one hull machine gun. Even post-war, the M60 MBT had a smaller secondary turret for the commander's cupola.
The Cold War and beyond
M60's Tiananmen Square during the 1989 protests
Jeff Widener (The Associated Press) ]]
After WWII, tank development proceeded largely as it had before, with improvements to both the medium and heavy classes. Light tanks were now limited to the reconnaissance role, and in U.S. use, airborne support as well. However, the weight limitations of air transport made a practical light tank almost impossible to build, and this class gradually disappeared over time.
But the seeds for a true transformation had already been working their way into existing designs. A combination of better suspensions and greatly improved engines allowed late-war medium tanks to outperform early-war heavies. With only slightly more armour and somewhat larger engines to compensate, mediums were suddenly protected against almost all antitank weapons, even those mounted on heavy tanks, while at the same time having the mobility of a medium tank. Many consider the turning point to be the Panther, which became the basis for almost every tank design after it. However the Panther was not terribly well armoured, and could not really fight the heavy tanks on an equal basis.
1989 protests]]
The first tank to 'get it all right' is generally considered to be the British Centurion tank, which (in its later versions) was able to take hits from the infamous German 88 mm gun, was armed with the deadly 105 mm Royal Ordnance L7 that was superior to anything in the field, and could reach 56 km/h due to its excellent 650-hp Rolls-Royce Meteor engine. The Centurion replaced all British medium cruiser tanks and led to the demise of the heavy infantry tank class entirely, becoming what the British referred to as the Universal Tank, soon to be known as the main battle tank in most forces, abbreviated MBT.
In response to the threat of heavy antitank guided missiles (ATGMs), the focus in development shifted away from just a tank's size, to the technologies within it. The long range of ATGMs made it useless to concentrate resources into fewer heavy tanks, because they could no longer perform in the stand-off role, the one thing they were really useful for. So rather than just producing tanks with much thicker armour, radically more effective armour was implemented. Gun technology remained remarkably similar even to WWI-era gun technology, with most tanks in service still being manually loaded, but with big advances in shell effectiveness.
Although the basic roles and traits of tanks were almost all developed by the end of WWI, the performance of twenty-first-century counterparts had increased by an order of magnitude. They had been refined dramatically in response to continually changing threats and requirements, especially the threat of other tanks. The advancing capabilities of tanks have been balanced by developments of other tanks and by continuous development of antitank weapons.
Design
The three traditional factors determining a tank's effectiveness are its firepower, mobility and protection. The psychological effect on enemy soldiers of a tank's imposing battlefield presence is called shock action.
Firepower is the ability of a tank to defeat a target. This takes into account the maximum distance at which targets can be engaged, the ability to engage moving targets, the speed with which multiple targets can be attacked, and the capability to defeat armoured vehicles or entrenched infantry.
Mobility includes the speed and agility of driving cross-country, the types of terrain that can be covered, the dimensions of obstacles, trenches, and water that can be crossed, the ability to cross small bridges, and the distance that can be covered before refuelling is required. "Strategic mobility" also includes the ability to travel at high speed on roads, and the ability to be carried on rail or truck transport. Traditionally AFV mobility is measured by the following metrics:
- engine power
- engine torque
- power-to-weight ratio
- road speed
- off-road speed (a somewhat nebulous figure given the possible variation)
- road range
- off-road range
- weight (bridge classification)
- ground pressure
- width of trench crossed
- vertical step climbed
- angle of slope that can be climbed
- angle of side slope that can be negotiated
- ground clearance
- unprepared fording depth
- prepared fording depth (if different)
Protection is the amount of armour, the type(s), how it is arranged (i.e., sloped or not), and which areas are given more protection (e.g., the turret and tracks) and which receive less (e.g., the rear of the chassis). It also includes low profile, low noise and thermal signature, active countermeasures and other methods of avoiding enemy fire, and the ability to continue fighting after damage has been sustained.
Tank design is traditionally held to be a compromise between these three factors—it is not considered possible to maximise all three. For example, increasing protection by adding armour will increase weight and therefore decrease manoeuvrability; increasing firepower by using a larger gun will decrease both manoeuvrability and protection (due to decreased armour at the front of the turret).
How the compromise is achieved is influenced by a combination of factors, including military strategies, budget, geography, political will, and the requirement to sell the tank to other countries.
Examples of how different countries are influenced in their decisions are as follows:
- Britain has historically opted for better firepower and increased protection at the expense of some manoeuvrability. Britain maintains a small, highly trained professional army, and so tank crew survivability is important. As limited resources may be available, the crew needs to be able to maintain their tanks in the field.
- The USA has a large army with sophisticated weaponry and a complex array of mobile support services. As their tanks are expected to rarely be away from support and repair units, less emphasis is placed on the crew's ability to maintain the tank themselves or to continue fighting with it once damage has been sustained.
- Germany's tanks were completely outmatched by the Soviet T-34 on the WWII Eastern front. It lost more of its insufficiently-developed Tiger and Panther tanks due to mechanical breakdowns than enemy action. As a result, German tanks since have been designed to be very manoeuvrable, with a resulting decrease in protection. Enhanced reliability and lower maintenance requirements have also been important design goals.
- Soviet tanks are traditionally rugged, simple for production and maintenance ("quantity turns into quality"), as exemplified by the T-34. State-controlled design development proceeds in incremental changes. Extensive maintenance is expected to be done in specialized depots.
- Israel is a small, but relatively rich, nation, with limited manpower in a hostile political environment. Its primary concern is therefore crew survivability. To this end it is the only nation to have produced a main battle tank with the engine placed at the front and fuel surrounding the crew, to increase protection.
Weapons
Israel.]]
The main weapon of any modern tank is a single large gun. Tank guns are among the largest-calibre weapons in use on land, with only a few artillery pieces being larger. Although the calibre has not changed substantially since the end of the Second World War, modern guns are technologically superior. The current common sizes are 120mm calibre for Western tanks and 125mm for Eastern (Soviet and Chinese legacy) tanks. Tank guns have been able to fire many types of rounds, but their current use is commonly limited to kinetic energy (KE) penetrators and high explosive (HE) rounds. Some tanks can fire missiles through the gun. Smoothbore (rather than rifled) guns are the dominant type of gun today. The British Army and the Indian Army are now the only ones to field main battle tanks carrying rifled guns.
Modern tank guns are generally fitted with thermal jackets which reduce the effect of uneven temperature on the barrel. For instance, if it were to rain on a tank barrel the top would cool faster than the bottom, or a breeze on the left might cause the left side to cool faster then the right. This uneven cooling will cause the barrel to bend slightly and will effect long range accuracy.
Usually, tanks carry other armament for short range defence against infantry or targets where the use of the main weapon would be ineffective or wasteful. Typically, this is a small calibre (7.62 to 12.7 mm) machine gun mounted coaxially with the main gun. However, a couple of French tanks such as the AMX-30 and AMX-40 carry a coaxial 20mm cannon that has a high rate of fire and can destroy lightly armoured vehicles. Additionally, many tanks carry a roof-mounted or commander's cupola machine gun for close-in ground or limited air defence. The 12.7-mm and 14.5-mm machine guns commonly carried on US and Russian tanks and the French Leclerc are also capable of destroying lightly-armoured vehicles at close range.
Some tanks have been adapted to specialised roles and have had unusual main armament such as flame-throwers. These specialised weapons are now usually mounted on the chassis of an armoured personnel carrier.
Fire control
flame-thrower, can fire with reasonable accuracy while moving.]]
Historically, tank weapons were aimed through simple optical sights and laid onto target by hand, with windage estimated or assisted with a reticule. Range to the target was estimated with the aid of a reticule (markings in the gun sight which are aligned to frame an object of known size, i.e. a tank), which was later supplemented with a stereoscopic range-finder, later replaced by a laser range-finder. Consequently, accuracy was limited at long range and made concurrent movement and shooting largely impossible.
Most modern main battle tanks in the armies of industrialised countries use a laser range-finder but optical and reticule range-finders are still in use in older and less sophisticated vehicles. Modern tanks have a variety of sophisticated systems to make them more accurate. Gyroscopes are used to stabilise the main weapon; computers calculate the appropriate elevation and aim-point, taking input from sensors for wind speed, air temperature, humidity, the gun-barrel temperature, warping and wear, the speed of the target (calculated by taking at least two sightings of the target with the range-finder), and the movement of the tank. Infrared, light-amplification, or thermal night vision equipment is also commonly incorporated. Laser target designators may also be used to illuminate targets for guided munitions. As a result modern tanks can fire reasonably accurately while moving.
Ammunition
There are several types of ammunition designed to defeat armour, including High explosive squash head (HESH, also called high explosive plastic, HEP), High explosive antitank (HEAT), and kinetic energy penetrators (KEP, or armour-piercing discarding sabot APDS). For accuracy, shells are spun by gun-barrel rifling, or fin-stabilized (APFSDS, HEAT-FS, etc.).
Some tanks, including the M551 Sheridan, T-72, T-64, T-80, T-90, T-84, and PT-91 can fire ATGMs (anti-tank guided missile) through their gun barrel. This functionality extends the effective combat range of the tank beyond the range afforded by conventional shells. It also provides the tank with a useful weapon against slow, low-flying airborne targets like helicopters. The United States has abandoned this concept, phasing the M551 and M60A2 out of their forces in favour of helicopters and aircraft for long range anti-tank roles, but CIS countries continue to employ gun-missile systems in their main battle tanks.
Protection
CIS, 4th Tank Battalion, 4th Marine Division, US Marines.]]
The main battle tank is the most heavily armoured vehicle in modern armies. Its armour is designed to protect the vehicle and crew against a wide variety of threats. Commonly, protection against kinetic energy penetrators fired by other tanks is considered the most important. Tanks are vulnerable to antitank guided missiles; antitank mines, larger bombs, and direct artillery hits can also disable or destroy a tank. Tanks are especially vulnerable to airborne threats. Most modern MBTs do offer near complete protection from artillery fragmentation and lighter antitank weapons such as rocket propelled grenades. The amount of armour needed to protect against all conceivable threats from all angles would be far too heavy to be practical, so when designing an MBT much effort goes into finding the right balance between protection and weight.
Armour
Most armoured fighting vehicles are manufactured of hardened steel plate, or in some cases aluminium. The relative effectiveness of armour is expressed by comparison to rolled homogeneous armour.
Most armoured vehicles are best-protected at the front, and their crews always try to keep them pointed toward the likeliest direction of the enemy. The thickest and best-sloped armour is on the glacis plate and the turret front. The sides have less armour and the rear and roof are least protected. World War Two American M4 Medium (British name, Sherman) tank crews found the German Tigers to be practically invulnerable from the front, and were forced to employ flank attacks. Today, tanks are vulnerable to specialised top-attack missile weapons and air attack. During WW2, aircraft rockets earned a formidable reputation, especially in France after the Normandy landings (Operation Neptune); post-war analysis revealed many reported kills were near-misses. Aircraft cannon firing armour-piercing ammunition, such as the Hurribomber's 40mm or Stuka's 37mm, could be effective, also. Even a simple Molotov cocktail on the engine deck, however, may disable or destroy any tank.
Before the Second World War, Soviet tank designers started to slope the armour on several tanks, most famously the T-34. Angling armour plates greatly increases their effectiveness against projectiles, by increasing the effective perpendicular thickness of the armour, and by increasing the chance of deflection. German tank crews were said to be horrified to find that shots fired at the angled plates of T-34s would sometimes simply ricochet.
Even light infantry antitank weapons can immobilise a tank by damaging its suspension or track. Many tracked military vehicles have side skirts, protecting the suspension.
High explosive antitank weapons (HEAT), such as the bazooka, were a new threat in the Second World War. These weapons carry a warhead with a shaped charge, which focuses the force of an explosion into a narrow penetrating stream. Thin plates of spaced armour, steel mesh "RPG screens", or rubber skirts, were found to cause HEAT rounds to detonate too far from the main armour, greatly reducing their penetrating power.
Some antitank ammunition (HESH or HEP) uses flexible explosive material, which squashes against a vehicle's armour, and causes dangerous spalling of material inside the tank which may kill the crew without penetrating the armour. As a defence, some vehicles have a layer of anti-spall material lining their insides.
Since the 1970s, tanks have been protected by more complex perforated or composite armour, a sandwich of various alloys and ceramics. One of the best types of passive armour is the British-developed Chobham armour, which is comprised of spaced ceramic blocks contained by a resin-fabric matrix between layers of conventional armour. A form of Chobham armour is encased in depleted uranium on the very well-protected M1A1 Abrams MBT.
The Israeli Merkava tank takes the design of protection systems to an extreme, using the engine and fuel tanks as secondary armour.
Grenade launchers, smoke and passive defences
Most armoured vehicles carry smoke grenade launchers which can rapidly deploy a smoke screen to visually shield a withdrawal from an enemy ambush or attack. The smoke screen is very rarely used offensively, since attacking through it blocks the attacker's vision and gives the enemy an early indication of impending attack. Modern smoke grenades work in the infrared as well as visible spectrum of light.
Some smoke grenades are designed to make a very dense cloud capable of blocking the laser beams of enemy target designators or range finders and of course obscuring vision, reducing probability of a hit from visually aimed weapons, especially low speed weapons, such as antitank missiles which require the operator to keep the tank in sight for a relatively long period of time. In many MBTs, such as the French-built Leclerc, the smoke grenade launchers are also meant to launch tear gas grenades and anti-personnel fragmentation grenades. Many Israeli tanks contain small vertical mortar tubes which can be operated from within the tank, enhancing the anti-personnel capabilities and allowing it to engage targets which are behind obstacles. There have been proposals to equip other tanks with dual-purpose smoke/fragmentation grenade launchers that can be reloaded from the interior.
Prior to the widespread introduction of thermal imaging the most common smoke grenade in AFV launchers was white phosphorus which created a very rapid smoke screen as well as having a very useful incendiary effect against any infantry in the burst area (e.g., infantry attempting to close with hand placed charges or mines).
Since the advent of thermal imagers most tanks carry a smoke grenade that contains a plastic or rubber compound whose tiny burning fragments provide better obscurant qualities against thermal imagers.
Some tanks also have smoke generators which can generate smoke continuously, rather than the instantaneous, but short duration of smoke grenades. Generally smoke generators work by injecting fuel into the exhaust, which partially burns the fuel, but leaves sufficient unburned or partially burned particles to create a dense smoke screen.
Modern tanks are increasingly being fitted with passive defensive systems such as laser warning devices, which activate an alarm if the tank is "painted" by a laser range-finder or designator.
Other passive defences include radio warning devices, which provide warning if the tank is targeted by radar systems that are commonly used to guide antitank weapons such as a millimetre and other very short wave radar.
Countermeasures
Passive countermeasures, like the Russian Shtora system, attempt to jam the guidance systems of incoming guided missiles.
Explosive reactive armour, or ERA, is another major type of protection against high explosive antitank weapons, in which sections of armour explode to dissipate the focussed explosive force of a shaped charge warhead. Reactive armour is attached to the outside of an MBT in small, replaceable bricks.
Active protection systems go one step further than reactive armour. An APS uses radar or other sensing technology to automatically react to incoming projectiles. When the system detects hostile fire, it calculates a firing resolution and directs an explosive-launched counter-projectile to intercept or disrupt the incoming fire a few metres from the target.
Exposed crew
Paradoxically, a tank is usually in its safest state when the commander is in a personally unsafe position, riding in the open, head out of the turret, with no personal protection save his helmet and a flak jacket. In this rather high position the commander can see around the vehicle with no restrictions, and has the greatest chance of spotting enemy antitank operations or natural and unnatural obstacles which might immobilise or slow down the tank. Tank periscopes and other viewing devices give a sharply inferior field of vision and sense of the countryside, despite constant advances in optics and electronics. Thus, when a tank advances in hostile territory with hatches closed, the commander and the crew might be personally safer, but the tank as a whole is more at risk given the extremely reduced vision. Improvements in onboard optical systems are ongoing, in order to overcome this problem.
Mobility
periscopei Merkava Mk-III) allow it to tackle most types of terrain, but they are only lightly armoured and are prone to mechanical failure.]]
There are essentially two main aspects of mobility to consider, the tank's basic mobility such as its speed across terrain and ability to climb obstacles, and its overall battlefield mobility such as range, what bridges it can cross, and what transport vehicles can move it. Mobility of a tank is categorised as either Battlefield Mobility, Tactical Mobility, or Strategic Mobility. The first is a function of its engine performance and capability of its running gear and is determined by aspects such as acceleration, speed, vertical obstacle capability and so on. The second is the ability of the tank to be readily transported within a theatre of operation. The third is its ability to be transported from one theatre of operation to other, dependent on its weight, air portability and so on.
A main battle tank is designed to be very mobile and able to tackle most types of terrain. Its wide tracks disperse the heavy weight of the vehicle over a large area, resulting in a specific ground pressure that might be lower than that of a man's foot. The types of terrain that do pose a problem are usually extremely soft ground such as swamps, or rocky terrain scattered with large boulders. In "normal" terrain, a tank can be expected to travel at about 30 to 50 km/h. The road speed may be up to 70 km/h.
The logistics of getting from point A to point B are not as simple as they appear. On paper, or during any test drive of a few hours, a single tank offers better off-road performance than any wheeled fighting vehicle. On the road the fastest tank design is not much slower than the average wheeled fighting vehicle design. But in practice, the huge weight of the tank combined with the relative weakness of the track assembly makes the maximum road speed of a tank really a burst speed, which can be kept up for only a short time before there is a mechanical breakdown. Although the maximum off-road speed is lower, it cannot be kept up continuously for a day, given the variety and unpredictability of off-road terrain (with the possible exception of plains and sandy deserts).
Since an immobilised tank is an easy target for mortars, artillery, and the specialised tank hunting units of the enemy forces, speed is normally kept to a minimum, and every opportunity is used to move tanks on wheeled tank transporters and by railway instead of under their own power. Tanks invariably end up on railcars in any country with a rail infrastructure, because no army has enough wheeled transporters to carry all its tanks. Planning for railcar loading and unloading is crucial staff work, and railway bridges and yards are prime targets for enemy forces wishing to slow a tank advance.
When moving in a country or region with no rail infrastructure and few good roads, or a place with roads riddled by mines or frequent ambushes, the average speed of advance of a tank unit in a day is comparable to that of a man on a horse or bicycle. Frequent halts must be planned for preventive maintenance and verifications in order to avoid breakdowns during combat. This is in addition to the tactical halts needed so that the infantry or the air units can scout ahead for the presence of enemy antitank groups.
Another mobility issue is getting the tank to the theatre of operations. Tanks, especially main battle tanks, are extremely heavy, making it very difficult to airlift them. Using sea and ground transportation is slow, making tanks problematic for rapid reaction forces.
Some tank-like vehicles use wheels instead of tracks in order to increase road speed and decrease maintenance needs. These vehicles lack the superior off-road mobility of tracked vehicles, but are considered by United States planners as more suited for rapid reaction forces due to increased strategic mobility.
Water operations
For most tanks water operations are limited to fording. The fording depth is usually limited by the height of the air intake of the engine, and to a lesser extent the driver's position. Typical fording depth for MBTs are 90 to 120 cm.
Deep fording
However, with preparation some tanks are able to ford considerably deeper depths. The West German Leopard I and Leopard II tanks can ford to a depth of several metres, when properly prepared and equipped with a snorkel. The Leopard snorkel is in fact a series of rings which can be stacked to create a long tube. This tube is then fitted to the crew commander's hatch and provides air and a possible escape route for the crew. The height of the tube is limited to around three meters.
Some Russian/Soviet tanks are also able to perform deep fording operations, however unlike the Leopard, the Russian snorkel is only a few inches round and does not provide a crew escape path. Russian snorkels are also fixed in length, providing only a couple of metres of depth over the turret height.
This type of fording requires careful preparation of the tank and the ingress and egress sites on the banks of the water obstacle. Tank crews usually have a negative reaction towards deep fording. This has influenced tactics in those countries where the psychological health of the crews or their capacity for rebellion is taken into account. However if properly planned and executed this type of operation adds considerable scope for surprise and flexibility in water crossing operations.
Amphibious tanks
Some light tanks such as the PT-76 are amphibious, typically being propelled in the water by hydrojets or by their tracks.
Often a fold down trim vane is erected to stop water washing over the bow of the tank and thus reducing the risk of the vehicle being swamped via the driver's hatch.
In World War II the M4 Medium (Sherman) tank was made amphibious with the addition of a rubberised canvas screen to provide additional buoyancy. It was propelled by propellers driven by the main engine. This was referred to as the Sherman DD (Duplex Drive) and was used on D-Day to provide close fire support on the beaches during the initial landings. The Sherman DD could not fire when afloat as the buoyancy screen was higher than the gun. A number of these DDs sank due to rough weather in the Channel (having been launched too far out). Those that did make it ashore, however, provided essential fire support in the first critical hours, getting off the beaches.
Power plants
D-Day, 4th Tank Battalion, 4th Marine Division, US Marines.]]
The tank's power-plant supplies power for moving the tank and for other tank systems, such as rotating the turret or electrical power for a radio. Tanks fielded in WWI all used petrol (gasoline) engines as power-plants. In the Second World War there was a mix of power-plant types used; a lot of tank engines were adapted aircraft engines. As the Cold War started, tanks had almost all switched over to using diesel, improved multi-fuel versions of which are still common. Starting in the late 1970s, turbine engines began to appear.
The weight and type of power-plant (influenced by its transmission and drive train) largely determines how fast and mobile the tank is, but the terrain effectively limits the maximum speed of all tanks through the stress it puts on the suspension and the crew.
Multi-fuel diesels
All modern non-turbine tanks use a diesel engine because diesel fuel is less flammable and more economical than petrol. Some Soviet tanks used the dark smoke of burning diesel as an advantage and could intentionally burn fuel in the exhaust to create smoke for cover. Fuel tanks are commonly placed at the rear of the tank, though in some designs, such as the Israeli Merkava, the diesel fuel tanks are placed around the crew area to provide an additional layer of "armour." Fuel has often been stored in auxiliary tanks externally, or by other means such as in a small trailer towed behind the tank, able to be detached during combat.
Modern tank engines are in some cases multi-fuel engines, which can operate on diesel, petrol or similar fuels.
Gas turbines
Gas turbine engines have been used as an auxiliary power unit (APU) in some tanks, and are the main power plant in the Soviet/Russian T-80 and U.S. M1 Abrams. They are comparatively lighter and smaller than diesel engines, at the same level of sustained power output (the T-80 was dubbed the Flying Tank for its high speed).
However they are much less fuel efficient, especially at low RPMs, requiring larger fuel tanks to achieve the same combat range. Newer models of the M1 have a small secondary turbine engine as an APU to power the tank's systems while stationary, saving fuel by reducing the need to idle the main turbine. T-80 tanks are commonly seen with large external fuel tanks to extend their range. Russia has replaced T-80 production with the less powerful T-90 (based on the T-72), while Ukraine has developed the diesel-powered T-80UD and T-84 with nearly the power of the gas-turbine tank.
Because of their lower efficiency, the thermal signature of a gas turbine is higher than a diesel engine at the same level of power output. On the other hand the acoustic signature of a tank with a muffled gas turbine can be quieter than a piston engine–powered one. The M1A2 was nicknamed Whispering Death for its quiet operation.[http://www.globalsecurity.org/org/news/2003/030324-whispering-death01.htm]
A turbine is theoretically more reliable and easier to maintain than a piston-based engine, since it has a simpler construction with fewer moving parts. In practice, however, those parts experience a higher wear due to their higher working speeds. The turbine blades are also very sensitive to dust and fine sand, so that in desert operations special filters have to be carefully fitted and changed several times daily. An improperly fitted filter, or a single bullet or piece of shrapnel can render the filter useless, potentially damaging the engine. Piston engines also need well-maintained filters, but they are more resilient if the filter does fail.
Like most modern diesel engines used in tanks, gas turbines are usually multi-fuel engines.
Sonic, seismic, and thermal traces
M1 Abrams
Stationary tanks can be well camouflaged in woodland and forested areas where there is natural cover, making detection and attack from the air more difficult. By contrast, in the open it is very hard to hide a tank. In both cases, however, once a tank starts its engine or begins to move it can be detected much more easily due to the heat and noise generated by its engine. The tank tracks across lands can be spotted from the air, and in the desert movement can stir up vast dust clouds several times the size of the tanks.
A recently stopped stationary tank has a considerable heat signature. Indeed even if the tank itself is hidden, for example behind a hill, it is still possible for a skilled operator to detect the tank from the column of warmer air above the tank. This risk can be reduced somewhat by the use or thermal blankets which reduce the radiation of heat while the engine and tracks cool. Some camouflage nets are manufactured from unevenly distributed mix of materials with differing thermal properties, which are designed to "randomise" or at least reduce the regularity of the thermal signature of a tank.
Tanks are powered by a diesel or turbine engine of a power comparable to a diesel locomotive. From the outside a diesel powered tank smells, sounds, and feels quite like a diesel locomotive. The deep rumble of even a single tank can be heard a great distance on a quiet day, and the sharp diesel smell can be carried far downwind. When a tank stands still with engine running the land trembles around it. When moving, the vibrations are greater. The acoustic and seismic signatures of multi-fuel engines are comparable. The acoustic signature of a turbine engine is much greater: its high-pitched whine can be much more easily distinguished from other sounds, near or far.
The very large power output of modern tank engines (typically in excess of 750kW or 1,000hp) ensure that they produce a distinct thermal signature. The unusually compact mass of metal of the tank hull dissipates heat in a fashion which marks it off sharply from other objects in the countryside. A moving tank is thus relatively easy to spot by good land-based or aerial infrared scanners. One of the reasons for the one-sided fighting during the Gulf Wars was that tanks like M1 Abrams had almost four times the night-time infrared scanning range of T-72s used by the Iraqi army. Another factor in the Gulf War was that, even when camouflaged and not moving, Iraqi tanks at night would cool at a different rate from their surroundings, making thermal detection easier.
Getting a tank to move proved to be important in the Kosovo conflict in 1999. During the initial few weeks of the conflict NATO air sorties were rather ineffective in destroying Serbian tanks. This changed in the final week of the conflict, when the Kosovo Liberation Army began to engage tanks. Although the KLA had little chance of destroying the tanks, their purpose was to get the tanks to move whereupon they could be more easily identified and destroyed by NATO air power.
Command, control, and communications
Commanding and co-ordinating a tank organisation in the field has always been subject to particular problems. Because of the isolation of small units, individual vehicles, and even the crewmen of a tank, special arrangements have had to be made. Armoured bulkheads, engine noise, intervening terrain, dust, and smoke, and the need to operate "hatches down" (or "buttoned up") comprise severe detriments to communications.
Every action of a tank's crew, movement and fire, is ordered by its commander. In some early tanks, the crew commander's task was severely hampered by having to load or fire the main armament, or both. In many small armoured fighting vehicles, even into the late twentieth century, the crew commander would relay movement orders to the driver by kicks to his shoulders and back. Most modern AFVs are equipped with an intercom, allowing all crew members to talk to each other, and to operate the radio equipment. Some tanks have even been equipped with an external intercom on the rear, to allow co-operating infantry to talk to the crew.
In the earliest tank operations, communications between the members of an armoured company were accomplished using hand signals or handheld semaphore flags, and in some situations, by crew members dismounting and walking to another tank. In World War One, situation reports were sent back to headquarters by releasing carrier pigeons through vision slits. Signal flares, smoke, movement, and weapons fire are all used by experienced crews to co-ordinate their tactics.
From the 1930s to the '50s, most nations' armoured forces became equipped with radios, but visual signals are still used to reduce radio chatter. A modern tank is usually equipped with radio equipment allowing its crew to communicate on a company or battalion radio network, and possibly to monitor a higher-level network, to co-ordinate with other arms of service. Company or battalion commanders' tanks usually have an additional radio. Communications on a busy network are subject to a set of formalised language rules called radio voice procedure.
Most armoured forces operate with the crew commander, and possibly other crew members, "hatches up", for best possible situational awareness. When taking fire, or in potential NBC conditions, tank crews "button up" and only view the battlefield through vision slits or periscopes, severely reducing their ability to acquire targets and perceive hazards. Since the 1960s, a tank's commander has had progressively more sophisticated equipment for target acquisition. In a main battle tank, the commander has his own panoramic sights (with night-vision equipment), allowing him to designate one or more new targets, while the gunner engages another. More advanced systems allow the commander to take control of the turret and fire the main armament in an emergency.
A recent development in AFV equipment is the increased integration of fire control, the laser range-finder, GPS data, and digital communications. U.S. tanks are fitted with digital computers which are connected into battlefield networks. These integrate known information on enemy targets and friendly units to greatly improve the tank commander's situational awareness. In addition to easing the reporting burden, these systems also allow for orders to be given complete with graphics and overlays, via the network.
See also
- Military communications
- Command, control, and communications (C3I)
Vulnerability
Whilst being a tremendously powerful weapon and the undoubted king of the land battlefield, the tank is not invulnerable. In fact it is the tank's superiority which has focused so much effort on improving antitank weapons.
Infantry
The tank is still vulnerable to infantry, especially in close country or built up areas. The armour and mobility of tanks, while usually notable assets, also makes them large and noisy. This can give enemy infantry the initiative, allowing them to spot, track and evade tanks until an opportunity presents itself for a stealthy counter-attack. This is why modern tactics insist on tanks being closely supported by friendly infantry.
For veteran troops, it is relatively easy for an infantry man to get close to a tank, especially if it is fully closed down (that is, the commander is fully inside the turret) as tanks have very poor visibility close in and especially to the sides and rear, unless the turret is pointing in that direction. If the crew commander is not closed down, that is, has exposed his head and perhaps upper body for the better view it affords him, then he can of course be shot.
In theory, it is easy for an infantry man to lie prone, | | |
