Utilisateur:Baptiste Deleplace/Char de combat-traduc

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This article is about armoured fighting vehicles. For other meanings, see Tank (disambiguation).

Soldats du 3e régiment de cavalerie blindée en éclaireur d‘autres soldats dans leur char de bataille M1 Abrams à Biaj, Irak.

A tank is a tracked armoured fighting vehicle designed to engage enemy forces head-on, using direct fire from a large caliber-gun. Heavy armour - as well a high degree of mobility - give it survivability, while the tracks allow it to cross even rough terrain at relatively high speeds.

Tanks were first used in World War I to break the deadlock of the trenches, and they evolved gradually to assume the former role of cavalry on the battlefield: to either flank opposing positions with fast movement, or to penetrate defences by massive concentration. Either movement may then be followed up by deep penetration into enemy rear areas, again supported by their high mobility. Tanks seldom operate alone, being organised into armoured units, usually in combined arms forces. Without such support, tanks, despite their armour and mobility, are vulnerable to special anti-tank artillery, anti-tank mines, infantry (at short ranges) as well as specialised anti-tank aircraft such as attack helicopters or close air support aircraft.

While tanks are expensive to operate and support, they remain among the most formidable and versatile weapons of the modern battlefield, both for their ability to engage other ground targets (including fortifications) and their shock value against infantry. Tanks and armour tactics have undergone many generations of evolution over nearly a century. Although weapons systems and armour continue to be developed, often at very high cost, many nations have reconsidered the need for such heavy weaponry in a period characterised by unconventional warfare.

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.

[modifier] Firepower

A US Medium Tank M4A3E8 tank fires from a prepared position during the Korean war

The crew of a tank must be able to quickly identify, engage, and destroy many types of targets on the battlefield, while maintaining high mobility. To this end, they are equipped with sophisticated detection and fire-control equipment, a large gun capable of firing armour-piercing and high-explosive ammunition, and machine guns for defence against infantry, light vehicles, and aircraft.

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 than the right. This uneven cooling will cause the barrel to bend slightly and will affect 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 U.S. 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.

[modifier] Protection

[modifier] Éviter la détection

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 dust clouds several times the size of the tanks.

Des réservoirs stationnaires peuvent être bien camouflés dans la régfion boisée et les secteurs couverts de forêts où il y a couverture normale, faisant la détection et l'attaque à partir de l'air plus difficile. En revanche, dans l'ouvert il est très difficile de cacher un réservoir. Dans les deux cas, cependant, une fois qu'un réservoir met en marche son moteur ou commence à se déplacer il peut être beaucoup plus facilement dû détecté à la chaleur et au bruit produits par son moteur. Les voies de réservoir à travers des terres peuvent être repèrées de l'air, et dans le désert le mouvement peut remuer vers le haut des nuages de poussière plusieurs fois la taille des réservoirs.

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 of 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.

Un réservoir stationnaire récemment arrêté a une signature considérable de la chaleur. En effet même si le réservoir lui-même est caché, par exemple derrière une colline, il est encore possible que un opérateur habile détecte le réservoir de la colonne d'un air plus chaud au-dessus du réservoir. Ce risque peut être réduit légèrement par l'utilisation des couvertures thermiques qui réduisent le rayonnement de la chaleur tandis que le moteur et dépistent frais. Quelques filets de camouflage sont manufacturés du mélange inégalement distribué des matériaux avec les propriétés thermiques différentes, qui sont conçues « randomisent » ou réduisent au moins la régularité de la signature thermique d'un réservoir.

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.

Des réservoirs sont actionnés par un moteur de diesel ou de turbine d'une puissance comparable à une locomotive diesel. De l'extérieur un réservoir à moteur diesel sent, ressemble, et se sent tout à fait à d'une locomotive diesel. Le grondement profond de même un à réservoir unique peut être entendu une grande distance un jour tranquille, et l'odeur diesel pointue peut être portée loin vent arrière. Quand un réservoir se tient toujours avec le moteur tournant la terre tremble autour de lui. En se déplaçant, les vibrations sont plus grandes. Les signatures acoustiques et séismiques des moteurs polycarburants sont comparables. La signature acoustique d'un moteur de turbine est beaucoup plus grande : son gémissement aigu peut beaucoup plus facilement être distingué d'autres bruits, près de ou loin.

The very large power output of modern tank engines (typically in excess of 750 kW or 1,000 hp) 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 War 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.

Le rendement de pouvoir très étendu des moteurs modernes de réservoir (typiquement au-dessus de 750 kilowatts ou de HP 1.000) s'assurent qu'ils produisent une signature thermique distincte. La masse exceptionnellement compacte du métal de la coque de réservoir absorbe la chaleur d'une mode qui des marques il au loin brusquement d'autres objets dans la campagne. Il est ainsi relativement facile repèrer un réservoir mobile par de bons modules de balayage infrarouges sur terre ou aériens. Une des raisons du combat recto pendant la guerre du Golfe était que les réservoirs comme M1 Abrams ont eu presque quatre fois la nuit la gamme qu'infrarouge de balayage de T-72s a employée par l'armée irakienne. Un autre facteur dans la guerre du Golfe était que, même lorsque camouflé et ne se déplaçant pas, les réservoirs irakiens la nuit se refroidiraient à un taux différent de leurs environnements, facilitant la détection thermique.

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.

Obtenir un réservoir au mouvement s'est avéré important en conflit de Kosovo en 1999. Pendant l'initiale peu de semaines des sorties d'air de l'OTAN de conflit étaient plutôt inefficaces en détruisant les réservoirs serbes. Ceci a changé en semaine finale du conflit, quand l'armée de libération de Kosovo a commencé à engager des réservoirs. Bien que le KLA ait eu peu de chance de détruire les réservoirs, leur but était d'obtenir les réservoirs pour se déplacer sur quoi ils pourraient plus facilement être identifiés et détruits par puissance de l'air de l'OTAN.

[modifier] Command, control and communications

Commanding and coordinating 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.

Commander et coordonner des chars sur le terrain a toujours été une source particulière de problèmes. Chaque blindé d'un groupe mais aussi chaque membre d'un même équipage sont isolés les uns des autres, ce qui a mené à la mise en oeuvre de solutions spécifiques. Les cloisons internes blindées, le bruit du moteur, les chaos du déplacement, la poussière, la fumée ou encore la nécessité de manoeuvrer toutes écoutilles fermées induisent de sérieux handicap de communication.

[modifier] Internal 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.

[modifier] Tactical communications

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 coordinate 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 coordinate 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.

[modifier] Computerised advances

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.

Modèle:Seealso

[modifier] Vulnerability

Despite being a powerful weapon and an impressive sight on the battlefield, the tank is vulnerable. In fact, the tank's effectiveness has led to massive development of antitank weapons and tactics.

[modifier] Infantry

Despite a tank's long-range firepower and shock action against inexperienced infantry, unsupported tanks are vulnerable to attacks by foot soldiers when attacking defensive positions, in close terrain, and in built up areas. Tank weapons have blind spots below their minimum depression, and a tank's suspension and relatively thin rear and top armour are vulnerable to attacks from nearby and from the upper storeys of buildings.

Tanks generally operate with closely coordinated infantry support to protect them from enemy infantry.

Infantry antitank weapons include early petrol bombs and antitank rifles, antitank hand grenades, magnetic mines and sticky bombs, and various handheld shaped-charge weapons including bazookas, RPGs and antitank guided missiles (ATGM).

[modifier] Artillery

Since World War II, tanks are sufficiently armoured to protect against artillery shell fragments. However, artillery guns usually also have a few rounds of antitank ammunition for defence against tanks in direct fire, in which it can be highly effective, as shown by the 88 mm gun of World War II.

Since the 1970s, there have been several types of artillery ammunition developed which can attack armoured vehicles. These include guided projectiles which home in on a target painted by a laser designator. There are also cluster munitions, saturating an area with bomblets which can attack top armour or create a minefield, and even smart submunitions which can identify and attack nearby tanks.

Modèle:Seealso

[modifier] Mines

Antitank minefields are area-denial weapons, helping to defend an area which is covered by fire, or channel enemy movements to prepared kill zones. Undefended minefields or individual mines planted in roadways are also used to delay movement and act as a nuisance weapon, but are not considered a highly effective military weapon—although their effect on morale and public support for military missions is used by insurgents.

Land mines attack a vehicle's relatively fragile suspension and thinner bottom armour, and many armoured vehicles are designed to reduce their effect. In most cases an anti-tank mine only immobilises a tank and most tanks can be fitted with anti-mine devices (mine plows, mine rollers, or mine flails). There are also off-route mines, which use a shaped-charge HEAT warhead to attack from the side. Guerilla fighters who don't have antitank mines at their disposal may build improvised explosive devices (IEDs) for harassment of armoured forces. However only the most heavy IEDs are capable of actually destroying a modern tank and are only capable of doing so if the tank drives directly over it.

[modifier] Aircraft

done

[modifier] Logistics

Tanks have very high logistical requirements. They require large amounts of fuel, ammunition, maintenance, and replacement parts to keep operating, even when not engaged in heavy combat. Armoured forces cannot fight effectively if their requirements are not met due to shortages, poor planning, or enemy actions, and historically, many tank offensives have failed in this way, for example Nazi Germany's Ardennes Offensive during World War II.

Les chars ont des besoins logistiques très lourds. Ils exigent de grandes quantités de combustible, munitions, entretien, et pièces de rechange pour continuer à fonctionner, même inoccupé. Les forces blindées ne peuvent pas combattre efficacement si toutes leurs exigences ne sont pas remplies, la planification optimal, historiquement, beaucoup d'offensives blindees ont échoué de cette façon, par exemple l'offensive nazie des Ardennes pendant la seconde guerre mondiale.

[modifier] Climate

Tanks can also be disabled by the weather: starter batteries and lubricants, and even engines may fail in extreme cold (during World War II campaigns in Russian winters, tanks were often kept running to prevent restart problems with frozen-solid engines). Engines and crew-members can also suffer from overheating during hot weather (partly combated in newer tanks by air-conditioning systems), or dust clogging important ducts.

Les chars peuvent également être neutralisés par le temps : les batteries des démarreurs et les lubrifiants, et même les moteurs peuvent ne pas demarrer dans le froid extrême. Pendant la seconde guerre mondiale dans l'hivers russe, des chars ont souvent ete forces a restee allumme pour prevenir des problèmes de demarrage (moteur et le carburant qui s'y trouve congelé). Les moteurs, et l'equipage, peuvent également souffrir de surchauffe par temps chaud (les nouveaux chars ont sont tous equipes de climatisation), ou la poussiere obstruer les conduits.

[modifier] Terrain

Tanks are also at a disadvantage in wooded terrain and urban combat environments, which cancel the advantages of the tank's long-range firepower, limit the crew's ability to detect potential threats, and can even limit the turret's ability to traverse. Some of these disadvantages have now been taken into account by special modifications for urban combat, and it should be noted that urban operations create additional hazards for almost all unit types, with tanks often retaining a high survivability (especially against improvised and most man-portable weapons) by virtue of their strong armour.

Les chars sont également dans une position défavorable dans les terrains boisés et les environnements urbains. Annulant l'avantage du tir à longue portée, limitant la capacité de l'équipage a détecter des menaces potentielles, et limitant meme la capacité de la tourelle a tournee (!). Certains de ces probleme sont maintenant pris en considération par des modifications spéciales notament pour le combat urbain (notons que les combats urbains créent des risques additionnels pour presque tous les types d'unité) avec une survie des chars qui s'est consideblement ammelioree (particulièrement contre armes improvisées et portatives) tout simplement en vertu de leur armure puissante.

[modifier] See also

Wikimedia Commons propose des documents multimédia libres sur Baptiste Deleplace/Char de combat-traduc.

Voir aussi sur Wikiquote les citations «  Baptiste Deleplace/Char de combat-traduc ».

Armoured warfare and tactics

• Armoured warfare
• Hull-down position
• Tank desant (infantry riding tanks into combat)

Armoured fighting vehicles

• Armoured car
• Armoured engineering vehicle
• Hobart's Funnies (specialised tanks used in the Invasion of Normandy)
• Infantry fighting vehicle
• List of armoured fighting vehicles
• List of modern armoured fighting vehicles
• Tankette

[modifier] Notes

[modifier] References

• Ogorkiewicz, Richard M. (1991). Technology of Tanks. Jane's Information Group, Coulsdon, Surrey. ISBN 0-7106-0595-1. 
• Ogorkiewicz, Richard M.. Design and Development of Armored Fighting Vehicles. 
• Time Life Books editors (1990). The Armored Fist. Time-Life Books, Alexandria Va.. ISBN 0-8094-8609-1; ISBN 0-8094-8608-3; ISBN 0-8094-8704-7; ISBN 0-8094-8705-5. 
• Weeks, John (1975). Men Against Tanks: A History of Anti-Tank Warfare. Mason Charter, New York. ISBN 0-88405-130-7; ISBN 0-7153-6909-1 (British printing). 
• Macksey, Ken. Tank Warfare. 
• Forty, G. The world encyclopedia of Tanks. Lorenz Books, 2006.

[modifier] External links

Modèle:Spoken Wikipedia

• Books about Tanks
• Photos showing some limits of a modern tanks movement abilities (from a private homepage, US tanks in Iraq)
• The Armored Tank turns 90 @ gizmag.com Also shows a tank designed by Leonardo DaVinci