In these cases, heat warheads often seem oversized in relation to the round's body. Classic evernote examples of this include the german Panzerfaust and soviet rpg-7. Variants edit a russian 3BK29 heat round Many heat-armed missiles today have two (or more) separate warheads (termed a tandem charge ) to be more effective against reactive or multi-layered armor. The first, smaller warhead initiates the reactive armor, while the second (or other larger warhead penetrates the armor below. This approach requires highly sophisticated fuzing electronics to set off the two warheads the correct time apart, and also special barriers between the warheads to stop unwanted interactions; this makes them cost more to produce. The latest heat warheads, such as 3BK-31, feature triple charges: the first penetrates the spaced armor, the second the reactive or first layers of armor, and the third one finishes the penetration. The total penetration value may reach up to 800 millimetres (31 in).
This is done either using fluted copper liners, which have raised ridges, or by forming the liner in such a way that it has a crystalline structure which imparts spin to the jet. 9 10 Besides spin-stabilization, another problem with any barreled weapon (that is, a gun) is that a large-diameter shell has worse accuracy than a small-diameter shell of the same weight. The lessening of accuracy increases dramatically with range. Paradoxically, this leads to situations when a kinetic armor-piercing projectile is more usable at plan long ranges than a heat projectile, despite the latter having a higher armor penetration. To illustrate this: a stationary soviet T-62 tank, firing a (smoothbore) cannon at a range of 1000 meters against a target moving 19 km/h was rated to have a first-round hit probability of 70 when firing a kinetic projectile. Under the same conditions, it could expect 25 when firing a heat round. 11 This affects combat on the open battlefield with long lines of sight; the same t-62 could expect a 70 first-round hit probability using heat rounds on target at 500 meters. A further problem is that, if the warhead is contained inside the barrel, its diameter becomes overly restricted by the caliber of that barrel. In non-gun applications, when heat warheads are delivered with missiles, rockets, bombs, grenades, or spigot mortars, the warhead size is no longer a limiting factor.
Since then, the penetration of heat rounds relative to projectile diameters has steadily increased as a result of improved liner material and metal jet performance. Some modern examples claim numbers as high as 700. 7 Stabilization and accuracy edit heat warheads are less effective if spinning, and grow ever less effective with faster spin. This became a challenge for weapon designers: for a long time, spinning a shell was the most standard method to obtain good accuracy, as with any rifled gun. However, the centrifugal force of a spinning shell disperses the charged jet. Thus, most hollow charge projectiles are fin-stabilized and not spin-stabilized. 8 In recent years, it has become possible to use shaped charges in spin-stabilized projectiles by imparting an opposite spin on the jet so that the two spins cancel out and result in a non-spinning jet.
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6 book It was this article that revealed to the American public how the fabled bazooka actually worked against tanks and homework that the velocity of the rocket was irrelevant. Most Americans were shocked to learn that even their enemies in World War ii had what the us army referred to as "shape charge warhead weapons". Citation needed After the war, heat rounds became almost universal as the primary anti-tank weapon. Variants of varying effectiveness were produced for almost all weapons from infantry weapons like rifle grenades and the M203 grenade launcher, to larger dedicated anti-tank systems like the carl Gustav recoilless rifle. When combined with the wire-guided missile, infantry weapons were able to operate at long-ranges also. Anti-tank missiles altered the nature of tank warfare throughout the 1960s and into the 80s, and remain effective. Effect edit cut-away view of a heat round; the copper-lined conical shaped area can be clearly seen Further information: Munroe effect The stream moves at hypersonic speeds in solid material and therefore erodes exclusively in the contact area of jet and armor material.
The correct detonation point of the warhead and spacing is critical for optimum penetration, for two reasons: If the heat warhead is detonated too near a target's surface, there is not enough time for the particle stream to fully develop. That is why most modern heat warheads have what is called a standoff, in the form of an extended nose cap or probe in front of the warhead. Notes 1 The distance is critical because the stream disintegrates and disperses after a short distance, usually well under 2 meters. The stream material is formed by a cone of metal foil lining, usually copper, though ductile iron and tin foil was commonly used during World War. The key to the effectiveness of a heat round is the diameter of the warhead. As the penetration continues through the armor, the width of the hole decreases leading to a characteristic fist to finger penetration, where the size of the eventual finger is based on the size of the original fist. In general, very early heat rounds could expect to penetrate armor of 150 to 250 of their diameters, and these numbers were typical of early weapons used during World War.
The need for a large bore made heat rounds relatively ineffective in existing small-caliber anti-tank guns of the era. Germany worked around this with the Stielgranate 41, introducing a round that was placed over the end on the outside of otherwise obsolete 37 millimetres (1.5 in) anti-tank guns to produce a medium-range low-velocity weapon. Adaptations to existing tank guns were somewhat more difficult, although all major forces had done so by the end of the war. Since velocity has little effect on the armor-piercing ability of the round, which is defined by explosive power, heat rounds were particularly useful in long-range combat where slower terminal velocity was not an issue. The germans were again the ones to produce the most capable gun-fired heat rounds, using a driving band on bearings to allow it to fly unspun from their existing rifled tank guns.
The heat round was particularly useful to them because it allowed the low-velocity large-bore guns used on their many assault guns to also become useful anti-tank weapons. Likewise, the germans, Italians, and Japanese had in service many obsolescent infantry guns, short-barreled, low-velocity artillery pieces capable of direct and indirect fire and intended for infantry support, similar in tactical role to mortars ; generally an infantry battalion had a battery of four. High-explosive anti-tank rounds for these old infantry guns made them semi-useful anti-tank guns, particularly the german 150 millimetres (5.9 in) guns (the japanese 70 mm Type 92 battalion gun and Italian 65 mm mountain gun also had heat rounds available for them by 1944 but they. High-explosive anti-tank rounds caused a revolution in anti-tank warfare when they were first introduced in the later stages of World War. One infantryman could effectively destroy any existing tank with a handheld weapon, thereby dramatically altering the nature of mobile operations. During World War ii, weapons using heat warheads were termed hollow charge or shape charge warheads. 5 Post war edit soviet 125 mm heat bk-14 The general public remained in the dark about shape charge warheads, even believing that it was a new secret explosive, until early 1945 when the us army cooperated with the us monthly publication Popular Science.
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By 1942, the piat had been developed by major Millis Jefferis. It was a combination of a heat warhead with a spigot mortar delivery system. While cumbersome, the weapon allowed British infantry to engage armor at range for the first time. The essay earlier magnetic hand-mines and grenades required them to approach dangerously near. 4 During World War ii the British referred to the monroe effect as the "cavity effect on explosives". 5 During the war, the French communicated Henry mohaupt's technology essay to the. Ordnance department, and he was invited to the usa, where he worked as a consultant on the bazooka project.
In mid-1941, germany started the production of heat rifle-grenades, first issued to paratroopers and, by 1942, to the regular army units ( Gewehr-Panzergranate 40, 46 and 61 but, just as did the British, soon turned to integrated warhead-delivery systems: In 1943 the püppchen, panzerschreck and. The german Panzerschreck was lethal at close range against armored vehicles The panzerfaust and Panzerschreck (tank terror) gave the german infantryman journal the ability to destroy any tank on the battlefield from 50150 meters with relative ease of use and training (unlike the British piat ). The germans made use of large quantities of heat ammunition in converted.5 cm pak 97/38 guns from 1942, also fabricating heat warheads for the mistel weapon. These so-called Schwere hohlladung (heavy shaped charge) warheads were intended for use against heavily armored battleships. Operational versions weighed nearly two tons and were perhaps the largest heat warheads ever deployed. 3 A five-ton version code-named beethoven was also developed. Meanwhile, the British. 68 at rifle grenade was proving to be too light to deal significant damage, resulting in it rarely being used in action. Due to these limits, a new infantry anti-tank weapon was needed, and this ultimately came in the form of the "projector, infantry, anti-tank" or piat.
the year 1940. This has some claim to have been the first heat warhead and launcher in use. The design of the warhead was simple and was capable of penetrating 52 millimetres (2.0 in) of armor. 2 The fuze of the grenade was armed by removing a pin in the tail which prevented the firing pin from flying forward. Simple fins gave it stability in the air and, provided the grenade hit the target at the proper angle of 90 degrees, the charge would be effective. Detonation occurred on impact, when a striker in the tail of the grenade overcame the resistance of a creep spring and was thrown forward into a stab detonator. By mid-1940, germany introduced the first heat round to be fired by a gun, the.5 centimetres (3.0 in) fired by the. K.37 L/24 of the panzer iv tank and the Stug iii self-propelled gun (7.5 cm.38 Hl/A, later editions b and C).
Contrary to a widespread misconception (possibly resulting from the acronym heat the jet does not melt its way through armor, as its effect is purely kinetic in nature. The heat warhead has become less effective against tanks and other armored vehicles due to the use of composite armor, explosive-reactive armor, and active protection systems which destroy the heat warhead before it hits the tank. Even though heat rounds are less effective against the heavy armour of 2010-era main battle tanks, heat warheads remain a threat against less-armoured parts of a main battle tank (e.g., rear, top) and against lighter armoured vehicles or unarmoured vehicles and helicopters. History edit, diagram of, piat ammunition, heat warheads were developed during, world War ii, from extensive research and development into shaped charge warheads. Shaped charge warheads were promoted internationally by the Swiss inventor. Henry mohaupt, who exhibited the weapon before world War. Before 1939, mohaupt demonstrated his invention to British and French ordnance authorities. Concurrent development by the german inventor's group of Cranz, add schardin, and Thomanek led to the first documented use of shaped charges in warfare, during the successful assault on the fortress. Eben Emael on Claims for priority of invention are difficult to resolve due to subsequent historic interpretations, secrecy, espionage, and international commercial interest.
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Top Female filmmakers on the "Political weight" of Studio, genre filmmaking. At Comic-Con, jennifer Yuh Nelson The darkest Minds susanna fogel The Spy Who dumped me and Christina hodson bumblebee share their experiences. For other uses, see. 1: Aerodynamic cover; 2: Air-filled cavity; 3: Conical liner; 4: Detonator; business 5: Explosive; 6: piezo-electric trigger, a high-explosive anti-tank heat ) warhead is a type of shaped charge explosive that uses the, munroe effect to penetrate thick tank armor. The warhead functions by having the explosive charge collapse a metal liner inside the warhead to form a high-velocity superplastic jet of liquid metal. This concentrated liquid metal jet is capable of penetrating armor steel to a depth of seven or more times the diameter of the charge (charge diameters, cd) but is usually used to immobilize or destroy tanks. Due to the way they work, they do not have to be fired as fast as an armor piercing shell, allowing less recoil.