In the second half of the 1920s, the Red Army was armed only with light tanks "Russian Renault", developed on the basis of the French FT17 and its further development, the light tank T-18 (MS-1) "small escort" plant "Bolshevik".
In the late 1920s, the military command considered it expedient to start developing medium tanks, while two directions were chosen: creating their own tank and an attempt to copy foreign samples.
In 1927, the military issued requirements for the development of a medium "maneuverable tank" with machine-gun and cannon armament. The development of the tank was started by the Main Design Bureau of the Arms and Arsenal Trust, then this robot was transferred to the Kharkov Steam Locomotive Plant No. 183.
Medium tank T-24
The development of design documentation for the tank was completed at the KhPZ, and at the beginning of 1930, a prototype tank was manufactured, which received the T-12 index. According to the test results of the tank, it was recommended to modify it, increase the power reserve, change the design of the tower, instead of the paired 6, 5mm Fedorov machine guns, install 7, 62 mm DT machine guns.
The tank was modified, and its serial production began under the T-24 index. 26 sets of tanks were manufactured, but only 9 tanks were assembled and production was stopped due to the start of production at this plant of BT-2 tanks, an analogue of the American light tank "Christie".
The layout of the T-24 tank was based on a three-tiered arrangement of weapons. A machine gun was installed in the hull, a cannon and two machine guns in the main turret, and another machine gun in a small turret located on the roof of the main turret on the right. The weight of the tank was 18.5 tons, the crew consisted of 5 people, commander, gunner, driver and two machine gunners.
The control compartment was in front, behind it was the fighting compartment, the engine-transmission compartment was in the back. The driver was located in front of the right. Commander, gunner and machine gunner in the main nine-sided tower and another machine gunner in the small tower. For the landing of the driver there was a hatch in the frontal sheet of the hull, for the rest of the crew there was one hatch in the main and small turrets.
A 45-mm cannon was installed in the frontal leaf of the turret, one 7.62-mm machine gun on each side of it. One 7, 62-mm machine gun was installed in the hull and small turret.
The hull and turret were riveted from armor plates, the thickness of the turret armor, the forehead and sides of the hull was 20 mm, the bottom and roof were 8.5 mm. The armor plates of the hull's forehead were located at rational angles of inclination.
The aircraft engine M-6 with a capacity of 250 hp was used as a power plant, providing a speed of 25.4 km / h and a power reserve of 140 km.
The undercarriage of the tank was unified with the undercarriage of the Comintern tractor and on each side consisted of 8 double rubberized road wheels of small diameter with vertical spring springs protected by armored casings, interlocked in four bogies of two, four supporting rollers, a front guide and a rear drive wheel.
The production of the tank at the plant was not prepared, there was no required equipment and specialists. The tanks were assembled almost by hand. Their reliability was very low, they often broke and went out of order, it was not possible to establish high-quality production of tanks.
At this time, the purchasing commission of Soviet specialists was considering in the West the issue of purchasing licenses for the production of Western models of tanks. As a result, it was decided not to develop their own tanks and to use the documentation for the tanks of England and the United States. The British six-ton Vickers light tank was taken as a prototype of the T-26 light tank and its production was mixed at the Bolshevik plant in Leningrad, and the American Christie M1931 tank, the production of which was located at the KhPZ, became the prototype of the BT-2 high-speed cruising tank.
Attempts by the KhPZ management and designers to continue the production and improvement of the T-24 medium tank did not lead to anything and work on it was stopped. The military leadership considered it expedient to purchase and manufacture Western tanks under license and thereby get rid of the mistakes that their designers have already gone through.
Medium tank T-28
The T-28 medium tank was developed in Leningrad in 1930-1932 and from 1933 to 1940 was mass-produced at the Kirov plant. A total of 503 T-28 tanks were produced. The prototype of the T-28 was the English medium three-turret tank "Vickers 16-ton".
In 1930, the Soviet procurement commission got acquainted with the British tank, but failed to buy a license for its production. It was decided to create a similar tank, taking into account the experience gained while studying the British tank.
At the beginning of 1931, the design bureau of the Artillery and Artillery Association (Leningrad) began designing the T-28 tank; in 1932, prototypes of the tank were manufactured and tested. According to the test results, the tank was put into service in 1932.
The T-28 tank was a three-turret medium tank with a two-tier arrangement of cannon and machine-gun armament, intended for fire support of the infantry. The control compartment was in front, behind it was the fighting compartment, in the aft part was the engine-transmission compartment, fenced off from the fighting compartment by a partition.
The turrets of the tank were located in two tiers, on the first in front there were two small machine-gun turrets, on the second - the main tower. Between the machine-gun turrets there was a driver's cabin with a folding armored door and a triplex hatch that opened upwards. From above, the cabin was closed by another hatch, which facilitated the landing of the driver.
The main turret had an elliptical shape with a developed aft niche and was identical in design to the main turret of the T-35 heavy tank. Outside the tower, along the sides, a handrail antenna was attached to brackets. Small machine gun turrets were also identical in design to the T-35 machine gun turrets. Each turret could rotate from the stop against the driver's cabin wall to the stop against the wall of the tank hull, the horizontal angle of fire of the machine gun was 165 degrees.
The tank's crew consisted of six people: a driver-mechanic, a radio operator-gunner from a machine gun, a commander and a gunner in the main turret, and two gunners of machine-gun turrets.
The hull of the tank was a box-shaped riveted-welded or welded structure, the same design was the tank turret. The armor of the tank was bulletproof, the thickness of the armor of the forehead of the hull was 30 mm, the forehead and sides of the turret were 20 mm, the sides of the hull were 20 mm, the bottom was 15-18 mm, and the roof was 10 mm. On the modification of the T-28E tank, additional armor was installed, armor plates with a thickness of 20-30 mm were attached to the hull and turrets. The shielding made it possible to increase the thickness of the armor of the frontal parts of the tank hull to 50-60 mm, and of the towers and the upper part of the sides to 40 mm.
The main armament of the tank was the 76, 2-mm gun KT-28 L / 16, 5 and was intended to combat enemy firing points and non-armored targets. It was not suitable as an armor-piercing weapon, and since 1938, the tanks were armed with a new 76, 2-mm L-10 L / 26 cannon with an initial speed of an armor-piercing projectile of 555 m / s, which made it possible to penetrate armor up to 50 mm thick at a distance of 1000 m.
The auxiliary armament of the tank consisted of four 7.62 mm DT machine guns, located in ball mountings. One of them was located in the frontal part of the main tower in an autonomous installation, to the right of the cannon, the other in the aft niche of the tower and two in the machine-gun turrets. On tanks of the latest series, an anti-aircraft turret with a DT machine gun was also installed on the gunner's hatch.
An M-17T aircraft engine with a capacity of 450 hp was used as a power plant. with., an attempt to install a diesel engine on the tank was unsuccessful. The tank developed a speed of 42 km / h and provided a power reserve of 180 km.
The undercarriage of the tank on each side consisted of 12 paired rubberized road wheels of small diameter, interlocked by means of balancers in 6 carriages with spring suspension, which, in turn, were interlocked into two bogies, suspended from the hull at two points, as well as 4 rubberized supporting roller.
The T-28 medium tank can be compared with foreign medium tanks of the same period with similar characteristics, these are the English Vickers 16-ton tank, the French Char B1bis and the German Nb. Fz.
The English "Vickers 16-ton" was essentially the "progenitor" of the T-28, with a weight of 16 tons, it was three-turret, was armed with a 47mm cannon with L / 32 and three machine guns, armor protection at the level of (12-25) mm and provided speed 32 km / h.
German Nb. Fz. there was also a three-turret, as an armament in the main turret a spark 75mm L / 24 cannon and a 37mm L / 45 cannon were installed, as well as three 7, 92-mm machine guns spaced across the towers, armor protection at the level of 15-20 mm, with a weight of 23, 4 tons, he developed a speed of 30 km / h.
The French Char B1bis had a 75mm cannon in its hull, and a 47mm long-barreled cannon with L27.6 and two machine guns in the turret, armor protection at the level of (46-60) mm and with a weight of 31.5 tons, developed a speed of 28 km / h.
The T-28, in comparison with the 16-ton Vickers, surpassed it in armament, protection and mobility. Compared to the Nb. Fz, the T-28 was inferior to him in armament, but superior in protection and mobility. Compared to the Char, the B1bis was inferior in armament and protection, but superior in mobility. In general, the combination of the main characteristics of the T-28 was at the level of foreign medium tanks of the same stage of development.
Heavy tank T-35
At the end of the 20s, attempts were made in the Soviet Union to create a heavy breakthrough tank. After several setbacks, in 1932, a design group specially created for the development of a heavy tank proposed a T-35 tank project, and in the fall of 1932 a prototype was manufactured. After testing and revising it, a second sample of the tank was made, which showed satisfactory results and was even shown in 1933 at a parade in Leningrad. In 1933, the serial production of the T-35 tank was entrusted to the Kharkov steam locomotive plant, where it was produced until 1940, a total of 59 T-35 tanks were produced.
The T-35 tank was a five-turret heavy tank with a two-tier arrangement of cannon and machine gun armament and bulletproof armor, designed to support and strengthen the infantry when breaking through fortified enemy positions.
According to the layout of the tank, the control compartment was in the hull, in the frontal part of the hull on the left was the driver. He had a triplex inspection hatch, which on the march folded up. Above the driver in the roof of the hull there was a hatch for his landing in the tank.
There were five towers on the roof of the hull. The main turret of a cylindrical shape with a developed aft niche, identical in design to the main turret of the T-28 tank, was located in the center on a turret box in the form of an irregular hexagon.
In the frontal part of the tower, on the trunnions, there was a 76-mm cannon, to the right of which a machine gun was located in an independent ball mount. Another machine gun was installed in the rear of the tower.
The two middle cylindrical turrets with two hatches in the roof for crew access were identical in design to the turret of the light tank BT-5, but without the aft niche. The towers were located diagonally from the right to the front and from the left to the rear in relation to the main tower. A 45 mm cannon and a coaxial machine gun were installed in the front of each turret.
Two small cylindrical machine-gun turrets in design were identical to the machine-gun turrets of the T-28 medium tank and were located diagonally from the left to the front and from the right to the rear. A machine gun was installed in front of each turret.
The main tower was fenced off from the rest of the fighting compartment with a partition, the rear and front towers communicated with each other in pairs.
The crew of the tank, depending on the production series, was 9-11 people. The main tower housed the commander-gunner, machine gunner and radio operator - loader. In each middle tower there were two people - a gunner and a machine gunner, in the machine gun towers there were one machine gunner.
The hull and turrets of the tank were welded and partially riveted from armor plates. The armor protection of the tank provided protection from bullets and shell fragments, as well as the frontal projection of the tank from small-caliber anti-tank artillery shells. The thickness of the armor of the forehead of the hull is 20-30 mm, the turret and sides of the hull are 20 mm, the bottom is 10-20 mm and the roof is 10 mm. In the process of producing tanks, the booking increased and the weight of the tank from 50 tons reached 55 tons.
The main armament of the tank was the 76.2 mm KT-28 L / 16.5 tank gun. The horizontal guidance was carried out by turning the turret with manual or electric drives. The power of the armor-piercing projectile, due to its low initial velocity, was very low.
Additional artillery armament consisted of two 45mm 20K L / 46 semi-automatic cannons with an armor-piercing projectile muzzle velocity of 760 m / s. Horizon guidance was carried out by turning the turret using a rotary screw mechanism
The auxiliary armament of the tank consisted of six 7.62mm DT machine guns, which were installed inside the turrets of the tank. On tanks of the latest series, an anti-aircraft turret with a DT machine gun was also installed on the gunner's hatch.
An M-17 aircraft engine with a capacity of 500 hp was used as a power plant, providing a speed on the highway 28, 9 km / h and a cruising range of 80 km.
The undercarriage of the tank on each side consisted of eight rubberized road wheels of small diameter, six carrier rollers with rubber tires, front and drive rear wheels. The suspension was blocked, two rollers in a cart with two coil springs suspension. The undercarriage was covered with a solid 10mm armor screen.
The five-turret T-35 tank, like the German Nb. Fz., was regularly used for propaganda purposes. He participated in maneuvers and parades, all newspapers wrote about him a lot and published his photographs, and he symbolized the power of the armored forces of the Soviet Union.
The concept of multi-turret heavy tanks in the interwar period was also tried to be implemented in France and England, but it turned out to be a dead end and did not receive further development in world tank building.
The ancestor of the "tank monsters" can be considered a French heavy two-turret tank Char 2C, huge in size, weighing 69 tons, with anti-cannon armor (30-45) mm thick, armed with a 75mm cannon and four machine guns and had low maneuverability and reliability. A total of 10 tanks were manufactured and the work was stopped at this.
More successful was the project of the British five-tower heavy tank A1E1 "Independent" weighing 32.5 tons, with armor protection 13-28 mm thick, armed with a 47-mm cannon and four machine guns. Thanks to a more rational layout of the tank, it avoided a number of shortcomings of the French Char 2C, one prototype was made, but due to the flawed concept of multi-turret tanks, it also did not go into mass production.
Heavy tank KV-1
The KV-1 heavy tank was developed in 1939 at the Kirov plant in Leningrad as part of the concept of heavy tanks needed to break into the enemy front and organize a breakthrough or overcome fortified areas.
Due to the fact that the concept of the T-35 heavy multi-turret tank turned out to be a dead end and attempts to create more advanced multi-turret tanks, such as the SMK and T-100, also did not succeed, it was decided to develop a heavy tank of a classic layout with powerful anti-cannon armor and armed a cannon capable of hitting enemy fortifications and armored vehicles.
The first prototype of the tank was manufactured in August 1939 and immediately sent to the Soviet-Finnish front to participate in the breakthrough of the Mannerheim Line, where it was successfully tested in a real combat situation. The tank could not be hit by any enemy anti-tank gun, and in December 1939 it was put into service. Before the start of the Great Patriotic War, tanks were produced only at the Kirov plant; a total of 432 KV-1 tanks were produced. With the beginning of the war, the production of the tank was organized at the Chelyabinsk Tractor Plant.
The KV-1 tank was of a classic configuration weighing 43 tons with anti-cannon armor, a powerful cannon, a diesel engine and an individual torsion bar suspension. The control compartment was located in the frontal part of the hull, the fighting compartment with a turret in the middle and the engine-transmission compartment in the stern.
The crew of the tank was 5 people, the driver was located in the center in front of the hull, the gunner-radio operator was to his left, three crew members were located in the tower, the gunner and loader were on the left of the guns, the commander was on the right. The crew was landed through a hatch in the turret above the commander's workplace and a hatch on the hull roof above the gunner's radio operator's workplace.
The hull of the tank was welded from rolled armor plates. The armor plates of the front of the vehicle were installed at rational angles of inclination (bottom / middle / top - 25/70/30 degrees). The thickness of the armor of the forehead, sides and turret is 75mm, the bottom and roof is 30-40mm. The armor of the tank was not affected by the 37-mm and 50-mm guns of the Wehrmacht, only from a caliber of 88 mm and above the tank could be hit.
The tank turret was produced in three versions: cast, welded with a rectangular niche and welded with a rounded niche. The gun mantlet was cylindrical of bent rolled armor plate 90 mm thick, in which a gun, a coaxial machine gun and a sight were installed.
The tank's armament consisted of a 76, 2-mm L-11 cannon, which was soon replaced by a 76-mm F-32 cannon with similar ballistics, and in the fall of 1941 a long-barreled ZIS-5 L / 41, 6 cannon was installed. Auxiliary armament consisted of three DT machine guns -29: coaxial with a cannon, course in the hull and stern in the turret.
A V-2K diesel engine with a capacity of 500 liters was used as a power plant. sec., providing a highway speed of 34 km / h and a cruising range of 150 km.
The undercarriage on each side contained 6 stamped gable road wheels of small diameter. Opposite each road roller, the travel stops of the suspension balancers were welded to the armored hull. The suspension was an individual torsion bar with internal shock absorption. The upper branch of the track was supported by three small rubberized carrier rollers.
The KV-1 tank was a major breakthrough in the development of heavy tanks, the optimal combination of firepower, protection and mobility allowed it to occupy a worthy niche in the class of heavy tanks of that time, it became the basis for the creation of heavy Soviet tanks of the IS series.
Heavy tank KV-2
The basis for the development of the KV-2 tank was the experience of the combat use of the KV-1 tank in the fall of 1939 in the Soviet-Finnish war during the breakthrough of the Mannerheim Line. The cannon of the KV-1 tank was not strong enough to fight against well-fortified enemy strongholds. It was decided to develop an assault tank based on the KV-1 with a 152mm howitzer installed on it. In January 1940, the KV-2 tank was developed and put into service in February. Serially produced at the Kirov plant until July 1941, a total of 204 KV-2 tanks were produced.
The tank was based on the KV-1 hull and a new turret with a 152 mm howitzer was installed on it. The weight of the tank reached 52 tons. The crew consisted of 6 people, an assistant loader was added in the tower in connection with the installation of a howitzer with separate ammunition loading. The landing of the crew in the turret was made through the aft door of the turret and a hatch in the roof of the turret in the place of the commander.
The tank stood out for its huge turret with a door in the rear of the turret, the height of the tank reached 3.25 m.
The KV-2 turret was produced in two versions: the MT-1 and the later "lowered" turret of less weight. The MT-1 tower had inclined zygomatic armor plates, and the "lowered" one had vertical ones. Both turret options were welded from rolled armor plates 75 mm thick.
A 152-mm M-10T tank howitzer was installed in the turret on trunnions, similarly to the KV-1, three DT-29 machine guns were installed in the KV-2.
Concrete-piercing and armor-piercing shells were used as ammunition for the howitzer, respectively, for both types of shells there were two types of charges. The use of a charge that does not correspond to the type of ammunition could lead to the failure of the weapon, therefore the crews were strictly forbidden to load one vehicle with shells and charges of different types for them.
Shooting on a full charge was strictly prohibited, since due to the high recoil and rollback, the turret could jam, and the components and assemblies of the engine-transmission unit could suffer from the shock. For this reason, shooting was allowed only from the spot, which further increased the tank's vulnerability in battle.
In the initial period of the war, the KV-2 easily destroyed any enemy tank, while it was invulnerable to enemy tank guns and anti-tank artillery. The KV-2, in comparison with the KV-1, did not find widespread use in the army, and with the beginning of the war, its production was discontinued.
Medium tanks A20 A30 A32
The T-34 medium tank did not appear as a result of requirements for the development of a medium tank, but grew out of an attempt to improve the family of high-speed tanks of the BT series and took from them the most successful components - the Christie suspension and the diesel engine.
At the end of 1937, the military issued to Kharkov plant No. 183 the tactical and technical requirements for the design of a light wheeled-tracked tank BT-20, according to which it was necessary to develop a wheeled-tracked high-speed light tank weighing (13-14) tons with three pairs of driving wheels with tracked and wheel travel, armor (10-25) mm and a diesel engine.
It should be noted that at that time a difficult situation developed in the design bureau of plant No. 183. Chief designer Firsov was dismissed from his post and accused of sabotage due to defects in the BT-5 tanks, a number of leading specialists were also dismissed, and they were soon shot. In the design bureau under the leadership of Firsov, studies have already been made on a fundamentally new tank and work in this direction has been headed by the newly appointed chief designer Koshkin.
The project of the BT-20 tank was developed and in March 1938 was submitted for consideration by the ABTU of the Red Army. When considering the project, the opinion of the military on the type of mover was divided. Some insisted on a tracked version, others on a wheeled-tracked version. The project of the tank was approved, the characteristics of the tank were specified, the requirements for security were increased, the crew was increased to 4 people and the permissible weight of the tank was up to 16, 5 tons, in this regard, the tank passed from the light class to the medium class. The purpose of the tank has also changed, now it was intended for independent actions as part of tank formations and for actions in tactical cooperation with other branches of the armed forces.
The plant was ordered to develop two versions of the tank, make two tracked and one wheeled-tracked tank and submit them for testing. In a short time, documentation was developed for two versions of the tank, their mock-ups were made and in February 1939 were submitted for consideration by the Defense Committee. Based on the results of the consideration, it was decided to manufacture both options in metal, test them and then decide which tank to launch into production.
In May 1939, a sample of the A20 wheeled-tracked tank with synchronized wheeled and tracked chassis was manufactured. The tank had three large-diameter drive rollers on each side and one guide roller in front, the nose of the tank hull was cut to rotate the guide roller. The tank's armament consisted of a 47-mm cannon and two machine guns, the tank's weight increased to 18 tons.
In June 1939, a sample of the tracked version of the tank was made, it was assigned the A32 index. The tank was distinguished by the installation of a 75-mm cannon, with the exception of a complex wheel drive on six rollers, reinforced by the armor of the tank hull, the installation of not four, but five rollers on each side, and a simpler, non-narrowed design of the tank hull nose. The weight of the tank increased to 19 tons.
In the summer of 1939, the A20 and A32 tanks passed field tests and showed good results. Based on the test results, it was concluded that the A32 tank has a weight reserve and it is advisable to protect it with more powerful armor. Factory # 183 was instructed to consider the possibility of increasing the tank's armor up to 45 mm. This was due to the fact that it became necessary to protect the tank from 37 mm anti-tank artillery, which was seriously developed in the late 30s. The study of the design of the tank showed that it was possible to do this without deteriorating the characteristics of mobility, while its weight increased to 24 tons.
A mock-up of such a tank was made, which received the A34 index, which successfully passed sea trials. Numerous changes were made to the design of the tank and a decision was made to produce two experimental A34 tanks. In December 1939, it was decided to adopt only the A34 tank with anti-cannon armor out of two A20 and A34 tanks, which became the T-34 tank, the weight of which increased to 26.5 tons.
At the beginning of 1940, two T-34 tanks were manufactured. They successfully passed the tests and in March were sent under their own power to Moscow to be shown to the leaders of the state. The show was a success and serial production of the T-34 began at the plant, in September the tank began to enter the troops.
Medium tank T-34
After the army operation of the T-34 tank, reviews from the army were extremely contradictory, some praised, others emphasized the unreliability of the components and systems of the tank, frequent breakdowns, unsatisfactory visibility and imperfection of observation devices, the tightness of the fighting compartment and the inconvenience of using the ammunition stowage.
As a result, ABTU developed a negative attitude towards the tank and, at their suggestion, a decision was made to stop production of the T-34 and resume production of the BT-7M. The plant's management appealed this decision and secured the resumption of production of the T-34. Many changes were made to the design documentation and control over the quality of the tanks was strengthened; by the end of 1940, only 117 tanks were manufactured.
As for the attitude of the military towards the T-34, I suddenly had to face it already in our time. In the early 1980s, while defending my dissertation, my opponent turned out to be a man from the "Stalinist Guard", who during the war was the head of the armaments department in the USSR State Planning Committee. We met, he looked like he was already over seventy, the star of the Hero of Socialist Labor was shining on his chest. When he learned that I was from a tank design bureau, he began to be keenly interested not in a dissertation, but in what was happening in the design bureau. During the conversation, he told me that before the war the military were against three types of weapons: the T-34 tank, the BM-13 Katyusha MLRS and the Il-2 attack aircraft. At the first stage of the war, they turned out to be one of the best in their class. Stalin forgot nothing, gave the command to find everyone and they were shot for sabotage. Whether fair or not, it's hard to say, times were like that. Here is such an interesting episode, I don’t know how real it is, but it was told by a man from that system.
Taking into account the comments received during the operation of the tank in the troops in January 1941, a project of a modernized T-34M tank was presented. In fact, it was a new tank, with a different hull and turret of increased volume, improved visibility from the tank, replaced observation and aiming devices, a chassis with a torsion bar suspension and road wheels with internal shock absorption, and a number of other measures.
In May 1941, it was decided to stop production of the T-34 and start production of the T-34M. In early June, the production of the T-34 was stopped and preparations for production for a new tank began. In total, 1,110 T-34 tanks were produced in the first half of 1941. With the beginning of the war, production of the T-34 was immediately resumed and the T-34M had to be forgotten for the time being.
The T-34 tank of the 1940 model was a medium tank weighing 26.5 tons with a crew of 4 people, with anti-cannon armor, armed with a 76, 2-mm cannon and two 7, 62-mm machine guns. The layout of the tank was classic, with a command compartment in front, a fighting compartment with a turret in the middle of the tank and a motor-transmission compartment in the rear of the hull.
The driver-mechanic was located on the left in the hull, to the right of him was the place of the radio operator-gunner. The tower on the left housed the commander and the loader on the right. In terms of the composition of the tank's crew, an unjustified decision was made to assign the gunner's functions to the commander, and he practically could not perform his command functions. In addition, in addition to the cramped layout of the tower, he had an unsatisfactory set of sights and observation devices, which were extremely poorly installed at his workplace.
The tank hull was welded from rolled armor plates. The lower ones were installed vertically, and the upper ones with rational angles of inclination (forehead top / forehead bottom / top of sides / stern - 60/53/40/45 degrees). The thickness of the armor of the forehead and sides is 45 mm, the stern is 40 mm, the bottom is 13-16 mm, the roof is 16-20 mm. The nose of the hull at the junction of the upper and lower frontal armor plates was made rounded. The upper and lower frontal plates were attached with tugs to a transverse steel beam. The driver's hatch was on the upper frontal plate, viewing devices were installed in the hatch.
The turret was also welded from rolled armor plates, the side and rear walls were inclined to the vertical at an angle of 30 degrees. The thickness of the armor of the forehead of the turret is 45-52 mm, the sides and stern are 45 mm. A cast turret was installed on some tanks of the 1940 model. On the roof of the tower there was one large trapezoidal hatch.
The command vehicles were equipped with a 71-TK-3 radio station with an antenna on the starboard side in front of the hull.
The armament of the tank consisted of a 76, 2-mm long-barreled cannon L-11 L / 30, 5, replaced in 1940 by the more advanced 76, 2-mm cannon F-34 L / 41, 5, and two 7, 62-mm machine guns DT. One machine gun was paired with a cannon, the other was placed in the body on a ball joint.
A V-2-34 diesel engine with a capacity of 500 hp was used as a power plant, providing a road speed of 54 km / h and a cruising range of 380 km.
The chassis of the tank was made according to the Christie scheme, on each side there were five large-diameter road wheels with an independent suspension of each roller on vertical coil springs inside the hull. The drive wheel was in the back, steering in the front. The tracks of the caterpillars were similar to those of the BT-7 tank, but with a greater width - 550 mm.
In terms of the aggregate characteristics of firepower, protection and mobility, the T-34 at the beginning of the war surpassed all foreign tanks of this class, but its use in the first battles was unsuccessful, most of the tanks were quickly lost.
The reasons for the low efficiency and high losses of the T-34 during this period were explained by the poor development of new tanks by personnel, poor visibility from the tank and an extremely unsuccessful layout of the fighting compartment, tactically illiterate use of tanks, their low reliability, lack of repair and evacuation means on the battlefield, hasty the introduction of tanks into battle without coordination with other branches of the armed forces, the loss of command and control of troops and long marches over long distances. Over time, all this was eliminated, and the T-34 was able to prove itself with dignity in the subsequent stages of the war.
The development and production of medium and heavy tanks, which began in the Soviet Union in the early 30s, in the early stages relied on copying foreign models and creating multi-turret medium and heavy tanks in accordance with the trends of that time. A long way was passed in the search for an acceptable concept of such tanks, as a result of which the medium tank T-34 and the heavy tank KV-1 of the classic layout were developed and put into mass production in the late 30s, which became examples of a successful combination of firepower, protection and mobility. tanks of these classes and largely determined the direction of development of Soviet and foreign tank building.
