Prayers for RR and his family. 
Prayers for RR and his family.
It is essential that a tank crewman understand how his tank is built, the reasoning behind the design and how these factors will influence the tactics used in the field. The commander of an armored unit, regardless of its size and force composition, must also become familiar with the all the tactics and techniques of tank warfare and how they are applied in practice.
TANK BASICS
Tanks are made up of three primary facets: Firepower, Protection, and Mobility, all of which are explained in detail below. In addition to these three basics, there are several other factors that can heavily influence the capabilities of individual tanks and their functions in relation to other military units. These include training, crew positions, visibility, optics, communications, ammunition stowage, vulnerabilities, and size.
FIREPOWER
The cannon on a tank is essentially a giant gun barrel. The longer the barrel, the more accurate and powerful the tank cannon is. The cannon barrel can have a smooth bore, like a shotgun, or rifling grooves engraved along its length which impart spin (and therefore greater accuracy) to the shell in its flight. However, most W.W.II cannon used some degree of spin-stabilization. An additional feature which affects the accuracy of the tank gun is the use of a muzzle brake, also called “muzzle whip”, which reduces the movement of the barrel during firing, as well as reducing the recoil and its effects on the tanks structure and crew. The accuracy of the shell is also affected by several other factors, which together are called the “ballistics” of the weapon. These factors include the rate of spin, wind resistance and crosswind. Gravity, range, and the duration of the shell’s flight will also affect the accuracy of the shell. The ammunition used in tank guns is generally of the “fixed” type, which means that the powder charge is fully enclosed and attached to the shell, like a rifle cartridge. Some of the larger cannon, especially howitzers and most large naval guns, may use separate-loading ammunition, which means that the shell is inserted into the breech, then individual bags of powder are forced in behind it.
As the armor used on armored vehicles grew thicker and more advanced, it became obvious that smaller guns were incapable of penetrating it. At first, this meant that the production of smaller guns ceased and the production of larger guns increased. When the development of armor quickly outstripped the capabilities of even the largest of the currently produced guns, new ammunition was designed to increase the penetrating power of the guns already in use. Initially, the ordinary solid shot, or armor piercing (AP) round, was used against tanks, while an ordinary high explosive (HE) shell was used against infantry and other ‘soft’ targets. The problem with solid shot was that its penetrating power could only be increased through greater weight that created an increase in the caliber of the gun, higher muzzle velocities, or increase in the chamber pressure or barrel length. A ballistic cap (APCBC) could also be mounted in order to keep the shot from shattering against thick armor. This problem was solved first by the Germans. By utilising a shell with a heavy tungsten-carbide core, (APCR), surrounded with a softer metal and fired through a barrel which tapered as it reached the muzzle, the softer metal would be squeezed from around the shot and as the barrel pressure increased, so did the muzzle velocity of the round. An unfortunate side effect was a rapid drop-off in velocity, which reduced the long-range performance of the round. A simplified version of this, called discarding-sabot (APDS), used a lightweight collar that fitted around the tungsten carbide core, and dropped off when fired. This had the advantage that it could be fired out of ordinary barrels and did not require a tapering bore to maintain the higher barrel pressure. For low velocity guns and rockets, another technological advance was required. This appeared in the form of the shaped charge (HEAT), in which the explosive filler was moulded so as to leave a cone-shaped space in the end facing the target. When the charge detonated, the concentration of explosive forces in that coneshaped cavity created a solid jet of plasma (known as the Monroe Effect) capable of punching through armor. This generally required a large warhead (at least 75mm) for good effect, but since the round was not dependent on higher velocity for penetrating power, it could penetrate the same amount of armor at 1,000 meters that it could at 10 meters. A shaped charge round mounted on the end of a stick and muzzle-loaded into the 37mm antitank gun was even developed by the Germans! Other types of ammunition, such as smoke producing shells, was also produced, but was reserved mainly for signalling and for screening troops, not for fighting. As a final note, ammunition and barrel qualities, due mainly to materials quality and workmanship, were also a limiting factor in main gun accuracy and effectiveness. These arguments go a long way towards explaining why the significantly larger 122mm cannons of the Soviet Union were inferior to the German 88mm and the American 90mm guns at the end of the war.