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Penetration of tanks

Hello, dear tankers! In this issue of Entertaining Mechanics, we will talk about such an important aspect of the game, how to break through the armor of a tank. Knowledge of armor penetration algorithms is twice necessary for any tanker, on the one hand it will allow you to more effectively strike the enemy, and on the other hand, will help you prolong your combat vehicle time under enemy fire. Therefore, we have divided this extensive topic into two issues: the protection of armored vehicles and the destruction of armored vehicles.

Do not forget that the World of Tanks is a game, not a training simulator, it, of course, largely seeks to comply with the laws of tank battles. But all the same has a number of conventions necessary to give the battles proper dynamics.

The processes occurring in reality when a projectile hits in a battle are too complex for rendering on the fly, and the scatter of results is such that the great Belarusian random seems to be a model of predictability. For example, a projectile that struck strictly perpendicular to the armor, it would seem, has a maximum penetrability, however, when the blanks split from internal stresses at the moment of impact, this parameter drops to zero. In the game, it has only a 25% variation from the nominal indicated in the description. If, say, your MS1 cannon has 51 mm armor penetration, then you should expect a spread from 38 to 64 mm. The spread of values ​​for damage is constructed in the same way.

Before we start talking about the geometry and mechanisms of breaking through, we will explain the terminology that we will use. Take a point on the armor and draw a tangent through it, the normal is a straight line drawn through the selected point perpendicular to the tangent, to put it in simple language - this is the usual perpendicular. We also clarify that we will consider the angle of occurrence of the projectile - this is the angle between the normal and the trajectory of the projectile at the point of impact, that is, at 0 degrees the chance of armor penetration will be maximum, and let's say at 80, most likely, a rebound will occur. It is worth noting that many players define this angle as the angle between the tangent and the trajectories of the projectile, noting, for example, that at angles less than 30 degrees, the chance of rebounding is very high. We will adhere to the terminology adopted among the developers of World of Tanks and in the military-technical literature, and consider the angle from the normal.

Another important concept is reduced armor. A shell with a large angle of entry into the armor has to punch a much larger thickness than indicated in the description of the tank. In accordance with the laws of geometry, the final layer or the reduced thickness of the armor to be pierced is calculated as the thickness of the armor to the cosine of the angle of entry. Of course, during the battle, no one will sit with a protractor and a calculator, and to calculate the reduced armor, it is enough to remember an intuitive rule: the greater the angle of entry of the projectile, the thicker the layer of armor that it needs to break through.

In order to make it easier for novice players to understand who and where to punch, a penetration marker for arcade and sniper sights was introduced into the game. If it is green, then if the projectile hits the armor along the normal, you will damage the combat vehicle, if it is orange, then the probability is 50 to 50, if it is red, then you should not spend an armor-piercing projectile. However, it’s impossible to believe the marker color unconditionally, the tank’s armor can be located at the most bizarre angles, besides, your shell may deviate from the aiming line and get a little wrong where you aim. And if you are aiming at the enemy’s lower frontal part, but he got a diamond, then you will not always be able to penetrate it, because even in the description of the tank, armor thickness is 50 mm, in this case your projectile will have to pierce 60-70-80 mm. armor, and even more, but the color of the marker does not change. But you should not get upset, because armor in real combat conditions behaves exactly the same way and tank designers made projectiles for cannons so that when hit they would tend to tighten to normal at the point of impact and slightly bring the angle of encounter with armor to 0 degrees. This effect is called the normalization of the projectile and since the update 0.8.0 is 4-5 degrees. Thus, we can adjust our reduced armor formula to the normalization angle. So, in the game when hit in an armor sheet at an angle of 45 degrees, the projectile will reach 40 degrees to the normal, and it will be a little to penetrate the armor, but it will be easier. For example, let's calculate the reduced armor, taking into account the normalization for two tanks known to all - the Tiger and the Royal Tiger. For clarity, we, on the contrary, will shoot at the upper frontal part from a distance of 50 m from guns, armor penetration of which is approximately equal to the thickness of the tested armor. For the sake of simplifying the calculations, we will assume that the projectile flies parallel to the ground, let's start with the World of Tanks Tiger. The thickness of its frontal armor is 100 mm, and it is located with a deviation of armor just 9 degrees from the vertical, the angle of entry will be the same, and taking into account the normalization we get 4 degrees. We shoot from gun L40 KVK48 with an average armor penetration of 106 mm. We see a lot of penetration of armor, since the thickness of the above armor will be equal to 100 mm. Now let us invite the Royal Tigger to the scene with a top frontal detail of 150 mm, check its durability with a 90 mm M3 gun with armor penetration of 160 mm. A sufficiently large number of hits did not cause the tank significant damage, because the armor has a tilt angle of 160 degrees, which means that the reduced armor has an impressive 212 mm, and since the maximum possible armor penetration of our weapon with an armor-piercing projectile is only 200 mm, we will not be able to disturb the royal imperturbability by shooting the upper armor. frontal detail.

Normalization will not help if the angle of entry is greater than 70 degrees, since in this case the armor-piercing projectile will simply ricochet. It is very important to remember, it’s not worth wasting shells, firing anywhere, you should at least approximately represent the angle at which it falls into armor. By the way, after the first rebound, the projectile does not disappear, it can still cause damage, but only within one tank, billiard methods will not work here, so do not expect that you can masterfully ricoche to another tank. Ricochets when firing armor-piercing or sub-caliber ammunition does not occur if the caliber of the gun exceeds the thickness of the armor. In this case, the projectile tries to pierce the armor regardless of the angle. When hit by external modules, for example, a chassis, an instrument or observation devices, the rebound also does not occur regardless of the angle, they generally have a special damage mechanism. Each module has its own reservation and points of strength, and the rules for calculating the above armor for them do not apply, and it is always necessary to break through a strictly defined thickness. In the event that this happens, the module loses points of strength, and the projectile continues to move and thus may well damage the tank hull. However, the rate of armor penetration of the projectile decreases by the thickness of the armor of the damaged module, and it will be harder to penetrate the main armor. This is the secret of the widely discussed nano-grounds.

The armor of the main machines in the games is divided into the main and the so-called screens. The penetration of the main armor removes strength points from the tank, and the screens of all - only weaken the projectile, lowering its armor penetration.

The screens are located at some distance from the main armor and usually have a small thickness, with the exception of screens on the masks of guns. It is very important to remember that when you break through only the screen, the tank does not lose strength points. Why is it important? Because this is one of the main causes of hits without damage. Think of the spread of armor penetration values. Even if the projectile overcame the screen, its armor penetration may be so weakened that it is not enough to break through the main armor.

You probably already know that in the game there are several types of ammunition that affect the armor in different ways. Armor-piercing shells - they are subject to the rules of normalization and ricochets in full. World of Tanks podkalibernye shells differ from armor-piercing shells only by increased penetrability. High-explosive shells do not ricochet, they have weak armor penetration, however, they are applied even when they explode on armor or close to a combat vehicle. Cumulative shells have increased armor penetration and do not ricochet, however, they are not subject to the rules of normalization.

Well, it is time to summarize the theoretical part and demonstrate the mechanism of armor penetration in action. Choose a target and shoot, at the point of the meeting of the projectile with armor and there is a screen. What happens in this case?

  1. the server builds the trajectory of the projectile according to a ballistic formula, determines the point on the screen, into which it fell, and the velocity vector of the projectile at the moment of impact. After that, the angle between the normal to the armor at the point of impact of the projectile and the velocity vector is calculated. If this angle is more than 70 degrees, and the caliber of the projectile does not exceed the thickness of the armor in this place 3 times, then there is a ricochet.
  2. if the rebound did not occur, and the caliber of the projectile exceeds the thickness of armor by more than 2 times, then with armor-piercing and sub-caliber ammunition, normalization increases in proportion to the increase in the caliber of the projectile to the thickness of the armor using the following formula. Thus, the larger the caliber of the projectile, the easier it is for him to pierce armor.
  3. the value of the armor penetration of the projectile is calculated, it depends on the firing distance. Starting from 100 m, the armor penetration of the projectile decreases and from a random deviation from the nominal, which is the plus - minus 25%.
  4. if the projectile breaks through the screen, then it flies further, and its armor penetration decreases in proportion to the screen thickness. After that, if the projectile meets the main armor, the algorithm repeats. Check on the rebound, normalization of the projectile, the calculation of the final armor penetration and in the case of penetration of the main armor, the tank is damaged according to the description of the gun, taking into account the 25% spread. Interestingly, in reality, the projectile, when hit by armor, will change the trajectory under the influence of normalization, but in the game for ease of calculation it continues to move straight, along the initial trajectory. The algorithm is applied sequentially, first for screens or external modules, then for the main armor. In this group of screens and armor in the path of the projectile may be several, and they make their way one after the other.

The adventures of shells inside the tank, the features of cumulative shells and the effect of high-explosive fragmentation ammunition will be discussed in the next issue.

Finally, it is time for the most entertaining part, namely for stories about tactical techniques that increase the survivability of the tank in battle. Will the theory help us with this, of course! And now we will consider the simplest techniques that logically follow from the knowledge we have just received.

So, reception number 1 - setting the tank with a diamond or the so-called invulnerability pose: you must position your tank in this way in relation to the enemy, so that he has to pierce your tank's armor at the least favorable angle. This technique requires a good knowledge of the reservation scheme of your combat vehicle. However, with his skillful execution, it will become much more difficult for the enemy to break through your tank. For example, let's talk about two widely known machines: the Soviet heavy tank IS-7 is armored so that you should not place it with a rhombus, because it gets the worst from the front when standing straight, but the German Tiger, which is at an angle to the direction of shelling , begins to reflect the shells with its rather thick forehead.

Reception number 2 - departure from the corner: you need to leave, cutting off the corner and not opening the vulnerable side and chassis of the tank for the enemy. You should also remember about the layout of your car and the scheme of its reservation, trying to expose the least vulnerable part of the tank. It only makes sense to drive sideways if the enemy has already fired a shot and doesn’t pay attention to you. Recall one of the basic laws of tank construction: almost any combat vehicle is armored in front much better than on the side, and on the side much better than on the back and on top, so you should always try to expose the forehead, turning to where the most dangerous shells fly.

Reception number 3 - horizontal swinging: this is probably the most common reception. It looks like a sharp short movement to the left - right. These movements make it harder for the enemy to target vulnerable areas and do not allow him to shoot at vertical booking zones. Also, this technique works well on tanks, the front of the tower which is flat. Rotating the turret to the left - to the right, while the gun is recharging, you seriously complicate the enemy in targeting her cheeks.

Reception number 4 - fishing for live bait: this is an element of aerobatics and it is very difficult to perform it in motion. We substitute the enemy side, giving him the opportunity to aim and at the time of his shot dock body. The projectile rebounds from armor without hitting the tank itself. In general, sudden unexpected maneuvers, if you learn not to shoot down your sight - a very effective method of tank duel. But remember that any rotation of the hull of a moving tank reduces its speed.

Reception number 5 - firefight with the enemy from behind the shelter: in many tanks in the game the tower is armored better than the hull, so you need to hide the lower frontal part behind some kind of shelter. If it is a destroyed enemy tank, an indestructible obstacle or an earthen hill, great. But you can hide behind one-off obstacles - cars, stone fences, shaky barns. One or two shots at you will survive these obstacles. By hiding part of the tank behind the obstacle, you force the enemy to target the less vulnerable parts of the combat vehicle, shoot at the side and track at a very acute angle and either get a ricochet or critical damage to the external module. But at the same time do not lose strength. For a shot, you can turn around or roll back a little, and then, without delaying to return to the starting position. The enemy will have to be very tense, aiming the vulnerable spots of your combat vehicle.

Reception number 6 - the use of natural shelters and shooting from unexpected places. The buildings in World of Tanks have windows and doors through which a projectile can fly. In the ruins there can be breaks through which it is convenient to shoot. Fences and strings of stones also allow you to fire at the enemy, showing him only a small part of the tower. Use this, study the maps and memorize such covers and positions.

That's all. We hope that by looking at this issue, you will be able to look at the enemy in a sniper scope for much longer, and visits to the hangar will become more rare.

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