Anti-tank warfare

Anti-tank warfare refers to any method of combating military armored fighting vehicles, notably tanks. The most common anti-tank systems include artillery with a high muzzle velocity, missiles (such as wire-guided HEAT), various autocannons firing penetrating ammunition, and anti-tank mines.

In the area of anti-tank warfare, three terms are often used: "mobility kill", "firepower kill", and "catastrophic kill". In a mobility kill (M-kill), the vehicle loses its ability to move, for example, by breaking a tank track; the target is then immobile but may retain full use of its weapons and still be able to fight to some extent. A firepower kill (F-kill) is some loss of the vehicle's ability to fire its weapons. M-kills and F-kills may be complete or partial, the latter corresponding to reductions in a target's ability to move or fire. A catastrophic kill (K-kill) removes the tank's ability to fight completely; this may entail complete destruction of the tank or disabling the weapon system(s) or crew.

Early systems

See also: Anti-tank rifle

Small cannon and large-calibre rifles were used against the early World War I tanks (e.g. Mark I tank) being introduced by the British Expeditionary Force. Many of these weapons proved to be almost useless. Some weapons included the armor piercing 7.92 K Bullets, then a larger anti-tank rifle when those became ineffective. Also grenades were used, and the Geballte Ladung ("Bunched Charge"), basically several regular grenades bound together. Tanks were also vulnerable to artillery and mortars, especially if they became stuck, which was a common occurrence at the time with difficult terrain and barbed wire, and they could be targeted more easily.

By the end of the war, a number of light guns, typically 37 mm (in British terms "2-pounder"), were being deployed on short carriages that proved to be considerably better. In addition most forces deployed large high-velocity rifles, typically of .50 cal (12.7 mm), with enough power to puncture the thin armor of the tanks of the era.

Anti-tank guns

See also: List of anti-tank guns, Tank gun.

Bofors 37 mm anti-tank gun as used by several nations

Anti-tank guns are guns designed to destroy armored vehicles. In order to penetrate the armor of tanks and other armored vehicles they generally fire shells of smaller calibre than regular indirect-fire artillery guns, propelling them at higher velocity.

Prior to World War II, anti-tank guns included both small towed guns and anti-tank rifles. Few had (or needed) calibers larger than 50 mm. Examples of guns in this class include the German 37 mm, US 37 mm, French 25 mm and 47 mm guns, British QF 2-pounder (40 mm), and Soviet 45 mm. All of these light weapons could penetrate the thin armour found on most pre-war and early war tanks.

German PaK 38 50-mm anti-tank gun

At the start of World War II many of these weapons were still being used operationally, along with a newer generation of light guns that closely resembled their WWI counterparts. These guns were decreasingly effective as tank armor improved. For instance, the new German lightweight 37 mm gun was quickly nicknamed the "tank door knocker" (German: Panzeranklopfgerät), once Soviet T-34 and KV tanks were encountered; all it seemed to do was announce its presence.

All combatants quickly introduced newer and more powerful guns, and the anti-tank rifle declined in importance, although many were still in use as late as 1943. The "typical" towed gun by late 1942 was 50 mm or larger; the Germans had an excellent 50-mm high-velocity design, while the British introduced the QF 6-pounder which was adopted, with minor modifications, by the US Army as the "57 mm Gun M1". A year later, sizes had grown due to pressure on the Eastern Front, German guns were now 75 mm and the famous 88 mm. The Red Army used a variety of 45 mm, 57 mm, and 100 mm guns, as well as deploying general-purpose 76.2 mm and 122-mm guns in the anti-tank role. The British QF 17 pounder, whose design had begun before the 6 pounder entered service, was smaller at 76.2 mm but delivered its excellent armour piercing shell at high speed.

British 17 pounder AT gun at Nijmegen, 1944

As the guns grew in size they became less mobile, making the dedicated anti-tank gun more vulnerable to enemy fire. Earlier weapons had been light enough to be moved a short distance by their crews. This was impossible with the much heavier weapons becoming common by mid-war. In addition to their lack of mobility, these guns offered almost no protection to the crew and were thus vulnerable to infantry and artillery fire. This gave impetus to the development of the tank destroyer, generally lightly-armoured vehicles providing mobility and some protection against HE fire. These self-propelled (SP) AT guns were far more effective than their towed counterparts.

German PaK 40 75 mm anti-tank gun

German-designed tank destroyers usually employed obsolescent or obsolete tank chassis (often from conquered nations such as French or Czech designs), and installed an AT gun on a turret-less superstructure, saving on weight. Some designs were lower and enclosed giving better protection to the crew and proving hard to spot when lying in defensive positions. US tank destroyers on the other hand retained fully rotating turrets and sacrificed armour to carry larger and longer guns than those mounted on contemporary medium (all-purpose) tanks (76 mm long gun on M10 and M18 designs, then a 90 mm long gun on M36). Overall, the German solution proved to be more successful and was later copied by the Soviets with their SU-85 and SU-100 self-propelled anti-tank guns.

On the whole anti-tank guns and self-propelled anti-tank guns were most effective in defence rather than attack.

By the end of the war the concept of the dedicated, conventional anti-tank gun was declining, with few new designs introduced after 1945. The guns had become so large that they were essentially immobile. Instead, newer recoilless weapons and rocket launchers were developed.

Infantry weapons

Grenades

Sticky bomb in production

There were many types and kinds of anti-tank grenades. These ranged from hollow charge designs (e.g., the British No. 68 AT Grenade), to ones that simply contained a lot of explosive (the British No. 73 Grenade). To increase their effectiveness, some grenades were designed so that they adhered to the tank either through an adhesive (sticky bomb) or with a magnet. The Germans used a magnetic grenade ("Hafthohlladung 3") to ensure that the shaped charge would fire at the optimal 90° angle to the armour.

There was also a special type of grenade called the Nebelhandgranaten or Blendkörper ("smoke hand grenades"), which was supposed to be smashed over an air vent and fill the tank with smoke, widely used by both sides in World War II. Molotov cocktails also saw much use, especially in the Winter War, early tanks being very vulnerable to them, but later tanks required a well-thrown bottle directly over the engine compartment to have any effect at all.

Shaped charge weapons

British PIAT

The development of light, man-portable, anti-tank weapons took off during the Second World War. Most were based on the Munroe effect which led to the development of the high explosive shaped charge. These weapons were called High Explosive Anti-Tank (HEAT). The destructive effect was entirely down to the explosion, so the speed of the round made no difference to the amount of damage inflicted. The effect was also concentrated, and could penetrate more armor for a given amount of explosives. The first HEAT rounds were rifle grenades, but better delivery systems were soon introduced: the British PIAT was propelled by an explosive charge combined with a powerful spring, the US Bazooka and the German Panzerschreck used rockets; and the German Panzerfaust was a small recoilless gun. The HEAT warhead was retroactively used to give more power to smaller calibre weapons such as in the conversion of the otherwise limited German 37 mm PaK guns to fire a large shell (that fitted over the barrel rather than down in it) to a greater range than the Panzerschreck could manage.

After the war, research on infantry anti-tank weapons continued, with most designers focused on two primary goals; first, an anti-tank weapon that could defeat more heavily-armored postwar tanks and fighting vehicles, and second, a weapon lightweight and portable enough for infantry use.

Soviet RPG-7

In the USA, the 2.36 in (60 mm) M9A1 bazooka rocket launcher evolved into the more powerful 3.5 in (89 mm) M20 "Super Bazooka", which was used to good effect against North Korean armored spearheads during the Korean War. However, the M20 proved difficult and cumbersome to portage on foot over long distances. In the 1960s, the U.S. Army adopted the M72 LAW rocket, a lightweight, collapsible rocket launcher with the ability to penetrate moderate thicknesses of enemy armor. During Vietnam War, the weapon was used primarily against NVA and Viet Cong defensive works and emplacements, as there were few encounters against enemy armor. Overall, the LAW was regarded as a success, though its ignition system frequently suffered from misfires in the heat and humidity of Vietnamese jungles. The LAW has since been replaced by the AT4 (M136).

The Soviets developed the RPG-2 from the German Panzerfaust 150. Further development lead to the ubiquitous RPG-7. The RPG-7 is one of the most widely used Anti-tank weapon, favored most by soldiers of Irregular Militaries. The RPG-7 could fire a range of different warheads, from Thermobaric warheads to a single HEAT or Tandem-charge HEAT warheads against Explosive reactive armour equipped tanks. The RPG-7 has a long combat history, and has been used in most wars from the Vietnam war all the way to present day wars. In modern times, the RPG-7 is generally used in an Urban environment, which would enhance their effectiveness due to the close ranges involved. However, the aging RPG-7 has evolved to the even more potent RPG-29 which has proven its worth in conflicts in the Middle East, disabling or destroying Merkava IV, Challenger 2 and M1 Abrams Main battle tanks.

Infantry close assault

The tank is still vulnerable to infantry, especially in close country or built-up areas. Rough terrain may expose the floor armour, and high ground such as multi-story buildings may expose the top armour. Their large size and loud noise can allow enemy infantry to spot, track, and evade tanks until an opportunity presents itself for counter-attack.

Because tank crews have limited visibility from inside the tank, infantry can get close to a tank given enough concealment and if the hatches are closed. If tank crewmen unbutton for better visibility, they become vulnerable to small arms fire. An infantryman cannot be targeted by a tank's main gun when close, as it cannot depress sufficiently. Close defense weapons such as pistol ports and pintle-mounted machine guns may still provide protection however.

Since heavy tank losses in some Second World War arenas, tank tactics have generally included close infantry support. Tanks in formation can support each other as well.

Whilst many hand-held infantry anti-tank weapons will not penetrate the front armour of a tank, they may penetrate the less heavily armoured top, rear, and sides. Damage to the tracks or running gear can inflict a mobility kill. Early WWII tanks had open vision slits which could be fired through to kill the crew. Later tanks' slits had thick glass, as well as sights and periscopes which could still be damaged with powerful small arms such as anti-tank rifles and heavy machine guns to hamper the crew's visibility. If all else fails, the hatch could also be forced open and grenades thrown inside, although later tank designs often have hatches designed to be difficult to open from the outside.

Tanks are also vulnerable to hand-placed anti-tank mines. Infantry have even immobilised tanks using a set of plates covered with leaves and dirt as dummy mines (the ruse being augmented by the crew's obscured vision). Infantry can then attack the stopped tank. This tactic was taught to the British Home Guard during World War II since they were not often provided with long-range anti-tank weapons.

In some cases in World War 2, a tactic of the some infantry was to run directly up to a tank, avoiding their main gun and mounted guns, and pour petroleum over and into the tank and light it, sometimes blocking the exit, burning the crew alive. Used by Soviet and German infantry respectively.

Artillery

Conventional artillery shells are not very effective against tank armour, except a lucky direct hit by a sufficiently powerful shell. A non-penetrating shell can still disable a tank through dynamic shock, internal armour shattering or simply overturning the tank.

In the last thirty years, however, a variety of artillery projectiles have been developed specifically to attack tanks. These include laser-guided projectiles, such as the US's now-cancelled Copperhead Cannon Launched Guided Projectile (CLGP), which increases the chances of a direct hit. Some of these CLGPs (including the Copperhead) have HEAT warheads instead of common HE.

Guided and unguided scatter munitions and submunitions have also been developed: a single artillery shell containing a number of smaller munitions designed to attack a tank. A six-gun battery might be able to fire several hundred submunitions in a minute or two.

In one form, the shell bursts in the air above the tank and a number of shaped charge (HEAT) or HEDP (High Explosive Dual Purpose) bomblets or grenades rain down. Any that hit the tank have a good chance of causing damage, since they are attacking the thin top armour.

Another form scatters a number of small anti-tank mines in the tank's path, which probably will not penetrate the armour but can damage a track, leaving the tank immobile and vulnerable.

More sophisticated are submunitions with a homing capability. Once again the shell explodes above the tank position and dispenses a number of submunitions. The munitions contain some circuitry to identify tanks, such as IR or millimetre radar; when a tank is identified, a rocket propellant is fired to shoot the projectile at the tank. These munitions will often descend by parachute, to allow time for target acquisition and attack.

All of the above but the CLGP can be fired from medium (122/152/155-mm) artillery, both tube and rocket.

There has also been development of large calibre (81 mm and larger) guided mortar munitions with both internal (e.g., IR or radar) or external (i.e., laser designator) guidance.

Mines and other explosives

A statue of a Vietminh soldier holding a Lunge AT Mine.

Main article: Anti-tank mine

• Hawkins mine
• The Wehrmacht employed the Goliath tracked mine, an unmanned demolition vehicle
• The Soviet Union employed anti-tank dogs during World War II, with very limited success; as a counterpart to the German Goliath the Teletank was used as a remote-controlled unmanned tank
• The Japanese forces employed suicide attacks with pole-mounted anti-tank mines dubbed Lunge Mines during late World War II

Developments since World War II

Despite a drastic drop in combat effectiveness (due to their diminished ability to penetrate the ever-heavier armour the various militaries fielded in World War II), the anti-tank rifle remained in use during the conflict. Notable examples include the Finnish Lahti L-39 (which was also used as a sniper rifle during the Winter War), the automatic Japanese Type 97 20 mm anti-tank rifle, the German Panzerbüchse 38, Panzerbüchse 39, the Polish Anti-tank rifle, model 35 and the Soviet 14.5mm PTRD and PTRS-41.

In the post-war era, HEAT became an almost universal choice outside of artillery and tank units. The British had developed the HESH (or High-Explosive Squash Head) warhead as an anti-concrete device for attacking fortifications during the war, and found it surprisingly effective against tanks. Although these systems allowed infantry to take on even the largest tanks, and, like HEAT, its effectiveness was independent of range, infantry typically operated at short range. Increasing use of combined arms tactics allowed the attacking infantry to suppress the anti-tank crews effectively, meaning that they could typically get off only one or two shots before being countered or forced to move.

The search for a more suitable, longer-range delivery system took up much of the immediate post-war era. The US invested in the recoilless rifle, delivering a widely-used 75 mm design, and less common 90 mm and 106 mm designs (the latter was usually mounted rather than infantry-handled). The 106 mm formed the basis of a dedicated anti-tank vehicle, the Ontos tank, which mounted six 106 mm rifles. The Soviet Union also built recoilless rifles in various calibers intended to be used as anti-tank weapons, most commonly 73 mm, 82 mm, and 110 mm (only the 73 mm remains in service with the Russian military today, though the other two can be found all over the world due to Soviet military aid during the Cold War). The British used a massive 120 mm (4.7 inch) design, the BAT series, which served from the 1950s until replaced by MILAN, but it was generally too heavy for infantry use and had to be towed by or mounted on a vehicle for maneuverability.

The successor to the recoilless rifle lay in the development of the (wire) guided missile, or Anti-Tank Guided Weapon (ATGW). Systems came into use in the late 1950s and 1960s that could defeat any known tank at ranges beyond that of the guns of the accompanying infantry. The United Kingdom, France, and other NATO countries were among the first to develop such weapons (e.g., the Malkara missile by the UK/Australia in 1958). The Soviet Union, and now Russia, put extensive development into these weapons; the first man-portable model to enter service was the AT-3 in 1961. The United States was one of the last, coming up with the BGM-71 TOW in 1970. For a time, it appeared that the tank was a dead end. A small team of infantry with a few missiles in a well-concealed position could take on a number of the largest and most expensive tanks. In the 1973 Yom Kippur War, Soviet first-generation wire-guided missiles employed by the Egyptian forces inflicted heavy casualties on Israeli tank units, causing a major crisis of confidence for tank designers.

Active protection systems such as the Russian Arena active protection system are starting to be more common, with similar systems such as the Israeli Iron Fist active protection system. The tank may be on a comeback because of active defense systems, which attack missiles in mid-air. This may allow the tank to be competitive on the battlefield once again.

Of the world's major armies, only the Soviet Red Army retained anti-tank guns in any significant quantity, mostly in 100 mm, 115 mm, and 125 mm calibers. The 125 mm anti-tank guns are extremely bulky and massive, and require large tractors to tow them for any significant distance. This is offset by their cheapness and potentially deadly effect, particularly now that they have been upgraded with laser rangefinders and depleted uranium ammunition. However, their tactical usefulness in many types of modern, mobile warfare is still unclear: in Desert Storm for example, tanks set up in emplacements were very vulnerable and could be spotted well in advance. In an environment with more cover, for example in urban terrain, they would be harder to spot.

Aircraft

Starting in World War II the first aircraft adapted for anti-tank warfare appeared: Hawker Hurricane MK. IID, Hawker Typhoon, Henschel Hs 129, Ilyushin Il-2, Junkers 87 "Stuka", Yak-9T and K. Many post-war aircraft, such as the A-10 Thunderbolt II and SU-25 Frogfoot, have been specifically built for close air support, including tank destruction. They can use a variety of weaponry, including large-caliber anti-tank guns, air-to-surface missiles (i.e. AGM-65 Maverick), volleys of unguided rockets, and various bombs (unguided or laser-guided and with or without submunitions such as HEAT bomblets, an example of which would be the CBU-100 Cluster Bomb).

Helicopters

British Army Westland WAH-64 Apache is an anti-tank helicopter.

Anti-tank missiles were first used in a helicopter-borne role by the French in the late 1950s, when they mounted SS.11 wire-guided missiles on Alouette II helicopters. While, initially, there were many teething problems, the possibilities were clear, such as providing the ability to attack the more lightly armoured top of the tank.

The anti-tank helicopter armed with ATGWs (Anti-Tank Guided Weapons) or anti-tank cannons is one of the biggest threats to a modern tank. The helicopter can position itself where it is not easily seen from a tank and then attack from any quarter, exposing the weaker parts of the tank's armour. The limited visibility from a closed-down tank also makes sighting a helicopter harder.

Most helicopter-launched ATGWs have sufficient range that they can under the right conditions be fired at a range too long for the tank to retaliate with its own weapons. This may change with the Israelis fielding the Lahat missile that can be fired from the main gun of the Merkava MBT. With both anti-tank and anti-helicopter role, it does level the playing field somewhat. The Indian Arjun tank has also been modified to fire this missile. The People's Republic of China has developed 100mm gun-launched missiles based on Russian designs such as the GP2 (based on the Russian Bastion). It has been reported to have successfully engaged aerial targets, as well as being an anti-tank missile. Similar missiles are available for Chinese tanks equipped with the 105mm gun. The Russians have also displayed a similar if more advanced system in the Reflex. The system involves an automatic targeting of an aerial/land target instigated by a laser warning system.

Although putting weapons on helicopters (probably) dates back to the 1955 with the Bell 47, the first specific attack helicopter that went into mass production was the Bell AH-1 Cobra in 1966. The AH-1 was equipped with TOW missiles in 1973 for anti-tank capability.

Tactics

Interwar years and WW2

Prior to WW2, a variety of improvised and dedicated weapons drove tactics. Initially, during WW1, light field pieces were deployed in the frontline trench system to fight tanks. These weapons could generally knock out a tank but were themselves vulnerable to artillery fire. Their position in the forward area made them vulnerable to loss also, and their use denuded regular artillery units of some of their firepower.

Engineer obstacles were perfected by the interwar years. Obstacles consisted of natural features such as ditches, streams and urban areas, or constructed obstacles such as anti-tank ditches, minefields, dragon's teeth, or log barriers. Obstacles were labour-intensive to construct and were not intended to stop an attack by themselves. Instead, the goal was to slow down the attacker, force them to conduct deliberate breaching operations with engineer support, and possibly cause them to reorient the direction of their attack into some better-defended area. Any delay on the attacker's part allowed the defender to move reinforcements into the threatened area and to learn the attacker's intentions. To be effective, all obstacles had to be covered by fire from other weapons systems. For example, a minefield may slow tanks down and force engineers to deploy on foot to clear it; mortar fire can then be used to defeat the engineers.

Anti-tank rifles were developed also. By the beginning of WW2, anti-tank rifle teams could knock out most tanks, and do so with a weapon that was man-portable and easily concealed. However, the upper limit on AT rifle performance meant that by mid-war, most tanks had armour sufficient to defeat their projectiles. The AT rifle teams were also vulnerable to virtually every weapon on the battlefield. Even under the best circumstances, AT rifles were also very short-range weapons requiring great courage from their gunners.

In the Japanese army, the use of satchel charges and pole charges was widespread. Although the charges could knock out any allied tank, the tactic was extremely close-range, and the sappers were vulnerable to all allied weapons.

Towed anti-tank guns were thought to be the primary means of defeating tanks. At battle of Kursk, for example, the Red Army deployed more artillery regiments than infantry regiments, and towed gun densities reached over 20 guns per kilometer of defended tactical zone. A towed gun was much cheaper than a tank, and could be concealed in a shallow position. When time allowed, dugouts with strong overhead cover could be constructed. Guns deployed on reverse slopes and in flanking positions could take a toll of attacking tanks. However, gun crews were vulnerable to artillery and mortar HE fire and enemy infantry. Their positions had to be carefully selected and, once engaged, they generally could not redeploy. Experience strongly suggested that towed AT guns were less effective than self-propelled AT weapons and took heavier casualties.

Self-propelled anti-tank guns were rare at the beginning of WW2, although the Belgian army deployed a few T.15 tank destroyers and the French army was developing several wheeled and tracked designs. The advantages of mobility and even thin armour protection were so compelling, however, that most armies were using self-propelled AT guns by mid-war. Examples of these weapons included the US M10, German Marder II, and Soviet SU-85.

Korean War

The Korean War highlighted the difficulties that can arise with tank forces when vulnerable logistical support is combined with poor terrain. In the early stages of the war, North Korea's well-equipped tank divisions were pushed back to the Yalu River, the border with China, by superior American air power combined with artillery and infantry support. However, when the Chinese entered the war, they managed to reverse the American advances with infantry power alone. Because of the terrain and the need to keep the tanks supplied, American tanks were limited to two main roads. The Chinese merely occupied the land between the roads and harried the American supply lines and troop transports along the road. The Chinese infantry stuck to land that was impassable to tanks, such as rocky prominences and rice paddies, neutralizing the advantage of both American armoured divisions and air support.

Future anti-tank

As bad as it looked for the tank in the 1960s, increases in depth of armor and improvements in armor technology meant that hand-held systems were no longer large enough to deliver enough power by the 1970s, and the introduction of Chobham armour by the UK and reactive armor by the USSR forced the HEAT rounds to be so large that in many cases they are not man-portable.

Weapon systems like the RPG-29 and FGM-148 Javelin use a Tandem warhead where the first explosion disables reactive armor, while the second explosion defeats the target by means of HEAT or a shaped charge.

Today the anti-tank role is filled with a variety of weapons, from portable "top attack" missiles, to larger HEAT missiles for use from jeeps and helicopters, a variety of high velocity autocannon, and ever-larger heavy tank guns.

One of the first lessons of the 2006 Israel-Lebanon conflict is the effectiveness of portable anti-tank missiles (in particular, Russian-made RPG-29, Metis-M, Kornet and European MILAN).

See also

• Czech hedgehog
• Anti-tank grenade
• Bumbar