EC-1 and EC-2
The heavy tanks JS-1 and JS-2 owe their appearance to the heavy KV-1 tank and to the medium tank with heavy KV-13 armor. The main stimulus for the development of new tanks was the appearance in the winter of the 1942-1943 on the Eastern front of the new German Tiger tanks. It was their appearance that forced the Soviet leadership to initiate the manufacture and conduct of state tests of two experimental Joseph Stalin tanks — the IS. The latest variants of the KV-13 were used as a running gear, but the armament of the two models was different.
The tests of two tanks took place from March 22 to April 19 1943, and were found successful. The State Commission noted that as a result of a more dense layout than that of the KV-1, the IS tanks, with a smaller mass (44 and 46 tons), have stronger booking and greater speed.
The EC-1 was in fact a deep modernization of the KV-1 tanks. It has been significantly redesigned weapons and armor protection. The tank received a new gearbox, while the EC-1 had a large number of parts from HF tanks of various modifications. The layout of the car was classic. His armored hull was divided from bow to stern into a control compartment, a combat compartment, and a power pack compartment. In the first one there was a mechanic driver, the other three crew members occupied jobs in the combat compartment, which united the tank turret and the middle part of the armored hull. Here the gun was installed, the ammunition was placed, part of the fuel tanks. The transmission and engine were located at the rear of the tank.
The armored body of the vehicle (with the exception of the frontal part) was welded from armor plates 90, 75, 60, 30 and 20 mm thick. The frontal part of the body of a streamlined shape was cast, in different parts its thickness varied from 30 to 120 mm, with other parts it was connected by welding. The streamlined turret of the tank was an armored casting of complex geometric shape. The thickness of its sides was 100 mm. Boards were located at an angle to the vertical, which increased projectile resistance.
The main weapon of the tank was the D-5T gun of the 1943 model of the year, which had a caliber of 85 mm. The gun was installed on the axles in the tower and was completely balanced. The tower was also balanced, its center of mass was on the geometric axis of rotation. Gun ammunition consisted of 59 shots of unitary loading. The shells were located in the tank turret and along both sides of the fighting compartment. This gun was a tank version of the 52-K anti-aircraft gun. A total of 130 X-1 tanks were launched.
The main machine, which bore the brunt of the battles of the last years of the war, was the EC-2, which was also called the EC-122, in this case the 122 figure designated the caliber of the tank gun. All were released 3475 tanks of this modification. The idea to equip a tank with a more powerful weapon was dictated by necessity. The X-NUMX-mm D-85-gun mounted on the EC-5 did not have sufficient capabilities to fight the new German medium tanks “Panther” and heavy tanks “Tiger”. In addition, 1-mm projectile had a small high-explosive action to combat the enemy's bunkers and billets.
As a result, it was decided to equip an 122-mm IS tank with a weapon developed on the basis of the A-19 cannon. This artillery gun was modified for installation in the tank. In particular, it received a muzzle brake, softening recoil, a more compact recoil device, improved placement of controls to provide the gunner with more comfortable conditions when working in the closed space of the tower. A revised version of the gun received index D-25T. Ammunition of the gun consisted of 28 shots of separate loading. Due to this fact, as well as the large weight of the shells, the firing rate of the gun was at the level of 3 rounds per minute, and even less in combat conditions. However, when hit at a target, a projectile fired from a given cannon often pierced German tanks through or led to the disruption of the turret. Also, the gun proved to be excellent when storming German cities, which the Nazis turned into real fortresses.
Another significant difference between the EC-2 tank and the EC-1 was the change in the frontal part of the hull. The EC-2 of the 1944 model of the year was equipped with a new “straightened” part of the frontal armor in order to increase the equipment resistance. Instead of a streamlined stepped end of a complex geometric shape, the EC-2 forehead began to be equipped with flat armor plates, the upper of which had the appearance of a trapezoid tapering to the turret, was located at an angle of 60 °, and its thickness reached 120 mm.
EC-3 was a further development of the series, appeared at the very end of the Great Patriotic War and did not participate in hostilities. This machine is most often considered the first Soviet post-war heavy tank. The main distinguishing feature of the tank is its characteristic frontal detail - the nose of the hull, which looked like a pike, and the tank itself was nicknamed “Pike” for it.
The development of the tank took place in 1944 year, the first batch was made in May 1945 year. Serial production of cars went to the middle of the year 1946, all was released 2311 tanks. The tank had a classic layout, its crew consisted of an 4 man. The tank was armed with the same X-NUMX-mm D-122T gun as on the EC-25 tank. At the same time, the tank received a new turret with a flat construction, which was subsequently used on all Soviet tanks from T-2 to T-54.
EC-3 had a very strong differentiated anti-sparring booking and was designed to protect against all modern tanks and PT-guns in the frontal projection and from the effects of most of the tanks and PT-guns from the sides. The forehead of the tank was reserved 110-mm. armor plates, according to the scheme called "pike nose". The forehead of the hull consisted of two wedge-converging plates arranged with an inclination of 56 ° to the vertical. Reservation of the boards reached 90 mm, with the slope of the armor in 60 °, in addition to this, the upper part of the sides was covered with 30-mm screens. The turret of the tank was a casting of homogeneous armor and had a flattened hemispherical shape. The thickness of its walls ranged from 220 mm at the base to 110 mm at the top, the front of the tower had armor close to 255 mm. At the same time, the weight of the tank remained at the level of 46 tons.
Remarkable is the fact that the EC-3, who did not take part in the war, became a member of the Berlin parade of Allied forces timed to victory in World War II. 7 September 1945 of the year 52 of the tank EC-3 drove through the streets of Berlin and made a strong impression on our anti-Hitler coalition allies.
EC-4 and EC-5
The EC-4 - Soviet heavy tank, put into service in the 1947 year, was produced from 1947 to 1948, a rather small series in 219 units. Was a further development of the tank EC-2. The main focus was on increasing the booking. Reservations for the hull forehead and tank sides reached 160 mm. Reservations for the frontal tower reached 250 mm, from the sides of the 200 mm. Such an increase in armor could not but affect the weight of the combat vehicle. The maximum weight of the tank approached the mark in 60 tons, which required the installation of a new B-12 engine in 750 hp, previous tank models were equipped with 520 hp engines.
The EC-5 was the prototype of a tank that never went into the series. Its main difference was the 100-mm C-34 cannon, which during the tests did not prove its reliability. As a result, the IS-4 went to the series, armed with the old proven D-25T gun of 122 mm caliber, while the tank ammunition reached 30 shells (increased by 2).
During operation, it became clear that the tank because of its mass can not cross many bridges and is faced with the difficulties of transporting various vehicles. In addition, a number of deficiencies in its transmission and its lack of reliability were revealed. At the end of the 1970-s all the tanks of this series were sent to the smelter.
EC-6 - an experienced Soviet tank, was not adopted for service. Development of the tank began in the year 1943. Sketch design of the machine was carried out from December 1943 to summer 1944. In total, two options were proposed, the first - “252 Object”, which had a mechanical transmission of the same type as the EC-3, but using large-diameter road wheels. Support rollers were missing.
A special feature of the other tank, the 253 Object, was an electromechanical transmission, which should have a positive effect on maneuverability and ease the control of the tank. The undercarriage was similar to the undercarriage of the EC-2. During the tests, the prototypes gave way to the EC-4 tank that was sent to the series.
An experienced Soviet heavy tank, developed in 1945-1947, the total number of machines produced did not exceed 50 units. One of the most powerful tanks of its time and the heaviest among the Soviet tanks, armed with the army was not accepted. This tank was in many ways a development of the EC-3 tank and was notable for the use of a number of technical solutions that were well ahead of their time. He had a classic layout. In this case, the crew of the tank increased to 5 people, in its composition appeared the second loader.
EC-7 in the museum in Kubinka, the first in a row
The tank inherited from the IS-3 the frontal part of the hull, made according to the "pike nose" scheme, while its reservation increased significantly. The forehead of the hull and side had a thickness of 150 mm. The forehead of the tower had a thickness of 210 mm, and the mask of the gun was 350 mm, the side armor of the tower reached 150 mm. The combat weight of the tank reached 68 tons, while the latter could develop on the highway a speed of 60 km / h. In many respects, the merit of the new M-50T diesel engine with a capacity of 1050 hp was here; this engine was a variant of the marine diesel engine. It is noteworthy that this was not the only detail inherited from the tank fleet.
The main armament of the tank was a 130-mm rifled C-70 gun with a barrel length in 57,2 caliber and an initial velocity of 33,4 kg projectile in 900 m / s. This tool was developed on the basis of 130-mm naval gun. The gun was equipped with a vertical wedge semi-automatic shutter, with which the rate of fire was increased to 6-8 shots per minute. OMS tank when conducting firing automatically guided gun, guided by the position of the sight, and made a shot. Tank ammunition included 30 shots separate loading.
The last heavy tank series of IP. Serially produced from 1954 to 1966 year. All were released from 2500 to 8000 similar tanks. He was in service with the Soviet army 40 for years, was retired from the Russian army in 1993 year. The tank was designed to replace the EC-2 and EC-3, and its development took into account the operating experience of the EC-4 and EC-7, which led to a decrease in tank mass to 50 tons. The decrease in the mass of the tank was accompanied by a decrease in the level of its reservation. During the design, the tank received indexes from the EC-8 to the EC-10, but after Stalin's death, the tank received a new name T-10.
Like the EC-3 and EC-7 tanks, this tank had a pike nose, but less modest booking compared to the last. The forehead of the hull had an 120 mm reservation., The 80 mm boards, the tower forehead - 201 mm., The 148 mm boards. Initially, the tank was equipped with an improved D-25TA gun, inherited from the EC-2 and EC-4 tanks, as well as the B-12-5 diesel engine with 700 hp power.
At the same time, the overwhelming number of tanks in service had the T-10М index, and in 60-s all the cars produced were upgraded to this modification. In it, the tank received a new 122-mm M-62-T2 gun, which was distinguished by high ballistics and two-plane 2-12 stabilizer "Downpour". Instead of a DShK, a 14,5-mm KPVT machine gun was installed on the tank, the turret design was changed, and its frontal booking was brought to 250 mm. The tank received a new, more powerful B12-6 engine with 750 horsepower, anti-nuclear protection and a set of night-vision devices for all tank crew members, with the exception of the loader.
Tank IS-3 on the go in Kubinka
Heavy tanks IS and KV