Work on the creation of various multi-turret tanks was characteristic of the Soviet tank school in the second half of the 1930s. One of the most famous and recognizable multi-turret tanks, of course, was the T-35 heavy tank, which was even produced in a small series. But it was far from the only multi-turret heavy tank that were created in the USSR in the pre-war years. One of the last Soviet tanks of this configuration (weapons were located in two towers) was the experienced SMK heavy tank (Sergei Mironovich Kirov), developed in the late 1930s.
Heavy tanks, which were designed in the USSR in the late 1930s, were a response to a new round of armor versus projectile confrontation. The development of anti-tank artillery, in particular the spread of 37-47 mm anti-tank guns, called into question the effectiveness of using tanks with armor less than 20-25 mm. The vulnerability of such machines was clearly demonstrated by the Spanish Civil War. The anti-tank guns, which the Francoists had, easily hit the well-armed but poorly armored Republican tanks, which massively used the Soviet T-26 and BT-5. At the same time, the problem of protection from anti-tank artillery concerned not only light tanks, but also medium and heavy vehicles. All of them had different weapons and sizes, but their armor was insufficient, this fully applied to the five-turret heavy tank T-35.
Already in November 1937, the Kharkov Steam Locomotive Plant (KhPZ) named after the Comintern received a technical task from the Armored Directorate (ABTU) of the Red Army to increase the reservation of the T-35 tank. The military demanded from the designers of the plant to increase the frontal armor up to 70-75 mm, and the armor of the sides of the hull and turret up to 40-45 mm. At the same time, the mass of the tank was not supposed to exceed 60 tons. Already at the stage of preliminary design, it became clear that with such a booking, it was simply unrealistic to keep within the established weight limit. It was for this reason that the decision was made to change the layout of the heavy tank, as a result of the research it was decided to stop at the three-turret scheme.
Heavy tanks T-35
In order to speed up the design work, it was decided to connect two powerful design bureaus to the development of a new heavy tank - the design bureau of the Leningrad Kirov plant (LKZ) and the design bureau of the plant No. 185 named after S. M. Kirov. The tanks developed in the indicated design bureaus were three-turret vehicles with armor up to 60 mm and weighing up to 55 tons. A 76-mm gun was installed in the main turret, and a 45-mm cannon in two small ones. It was planned to use a 800-1000 hp carburetor aircraft engine as a power plant, and a 1000 hp diesel engine was also considered. The design maximum speed was supposed to be up to 35 km / h, the crew - up to 8 people.
The creation of such a machine was quite difficult. The designers were looking for the optimal shape of the hull and turrets of the tank, they were faced with the question - to make them cast or welded from armor plates. For clarity, layouts were made of wood. At the LKZ, a group of engineers A. S. Ermolaev and Zh. Ya. Kotin created the SMK-1 tank (Sergey Mironovich Kirov). Already on October 10, 1938, the state mock-up commission reviewed the prepared drawings and mock-up of the new tank. Although a tank with anti-cannon armor, the T-46-5, had already been created at the plant, it was clear that the new combat vehicle would be much more unusual. In terms of layout, the first version of the SMK, which had three gun turrets, most of all resembled a cruiser. It was curious that the turrets of the tank were located not along the longitudinal axis of the hull, but with an offset - the front to the left, and the rear to the right. At the same time, the central tower was higher than the end ones and was installed on a massive armored conical base, thus, the placement of weapons was two-tier.
When creating QMS-1, the designers allowed themselves some deviations from the requirements of ABTU. For example, they decided to abandon the T-35-style suspension recommended by the military, opting for a torsion bar suspension. The designers understood that the suspension of the T-35 heavy tank was unreliable, it needed good protection - heavy and bulky armored screens. Therefore, even at the design stage, they abandoned it, for the first time in the Soviet Union using a torsion bar suspension on a heavy tank, which was already used at that time on light German and Swedish tanks. However, just in case, a version with a spring-balanced suspension from the T-35 was prepared. On December 9, 1938, the SMK-1 project, together with the "product 100" (T-100) design bureau of plant No. 185, was considered at a meeting of the Main Military Council. During the discussions, it was decided to reduce the number of towers to two. The weight savings due to the dismantled third turret could be used to increase the armor of the tank. In addition, work was allowed on a single-turret version of the tank, famous in the future heavy tank KV (Klim Voroshilov).
Heavy tank SMK
In January 1939, work began on the manufacture of the SMK tank, and on April 30, a new heavy tank first left for the yard of the plant, on July 25 of the same year, the tank left to undergo field tests. Two months later, on September 23-25, 1939, a heavy two-turret tank SMK, among other promising models of military equipment, took part in the government show in Kubinka. Even then, it was obvious that the SMK surpasses the T-35 in speed, power reserve, and cross-country ability. The SMK could climb slopes with a steepness of 40 degrees, while for the T-35, a steepness of more than 15 degrees became an insurmountable obstacle.
The SMK heavy tank had conical towers, which were located one after another, towering above the fighting compartment. The front (small) tower was 145 mm displaced to the left of the longitudinal axis of the combat vehicle, the rear (main) tower was located on a high conical turret box. The control compartment was located in the front of the tank, the engine-transmission compartment was behind the combat one. In the control compartment there were the seats of the driver and the gunner-radio operator, who was sitting to his right. In the small turret there are the gunner (turret commander) and loader positions, in the main turret - the tank commander, gunner and loader. Also, the tank was provided with a place to accommodate a technician.
The hull of the heavy tank was made of homogeneous armor, it was welded. By removing the third turret, the thickness of the upper part of the frontal hull plate was increased to 75 mm, the thickness of the other frontal and side armor plates of the hull and turret was 60 mm. Due to the use of a torsion bar suspension, the designers abandoned side screens, like that of the T-35 tank. In the frontal sheet of the hull, only the so-called plug hatch with viewing devices was located, the mechanical drive's landing hatch was placed on the roof of the hull. The achieved level of booking ensured reliable protection of the tank's crew and its equipment from the shelling of 37-47 mm armor-piercing shells at all combat distances.
The armament of the SMK heavy tank was powerful enough. The main turret housed a 76, 2-mm L-11 cannon paired with a 7, 62-mm DT machine gun, the vertical guidance angles of the gun ranged from -2 to +33 degrees. A 7.62 mm DT anti-aircraft machine gun was installed on the turret of the turret landing hatch, and a large-caliber 12.7 mm DK machine gun was located in the aft recess of the turret in a ball mount. The main turret turning mechanism had a differential mechanism, which allowed the electromechanical and manual drives to work simultaneously, which ensured a high smoothness and speed of guidance of the existing weapons. The small turret housed a 45 mm 20K cannon and a 7.62 mm DT machine gun paired with it, the gun pointing angles ranged from -4 to +13 degrees. Unlike the main tower, which could rotate 360 degrees horizontally, the small tower had a horizontal guidance angle of 270 degrees. The set of weapons was supplemented with a DT machine gun, which was installed in a ball mount in the frontal sheet of the hull, served by a radio operator gunner.
The tank's ammunition was just as impressive as the set of weapons. For the 76, 2-mm gun, there were 113 armor-piercing and high-explosive fragmentation shells, the ammunition load of the 45-mm 20K cannon consisted of 300 shells. To 12, 7-mm machine gun had 600 rounds, and the total ammunition for all DT machine guns was 4920 rounds.
The heart of the SMK tank was the AM-34BT V-shaped 12-cylinder carburetor aircraft engine, which was installed in the rear of the tank. The engine developed a maximum power of 850 hp. at 1850 rpm. In fact, it was no longer an aircraft engine, but a marine engine that was installed on torpedo boats. Three fuel tanks, located on the bottom of the tank in the fighting compartment, contained 1400 liters of fuel. The cruising range on the highway reached 280 km.
The layout of the heavy tank SMK
For each side, the undercarriage of the SMK tank consisted of 8 road wheels with internal shock absorption, four rubberized support rollers, a drive and a guide wheel. The suspension of the tank was torsion bar, without shock absorbers. The tracks were large-link with cast steel tracks.
The SMK tank underwent state tests together with two other heavy tanks - T-100 and KV. Tests began in September 1939 and took place at a test site near Moscow in the presence of the country's leaders. By the end of November of the same year, the mileage of the SMK tank had already exceeded 1,700 kilometers. In general, the new combat vehicle has withstood state tests. However, there were comments to it. It was noted that it was difficult for the driver-mechanic to drive a heavy tank, and for the commander it was difficult to control the fire of two guns at once and numerous machine guns in two towers.
The Soviet-Finnish war, which began on November 30, 1939, demonstrated that it would be very difficult to break through the fortifications of the Mannerheim Line without the use of heavy tanks. Under these conditions, the command of the Red Army decided to test new heavy tanks with anti-cannon armor in real combat conditions. For these purposes, all three new heavy tanks - SMK, T-100 and KV - were sent to the Karelian Isthmus. At the same time, the crews of the new tanks, in addition to the Red Army, were staffed with volunteers from among the factory workers, who had previously undergone combat training at special tank courses in Krasnoe Selo before being sent to the front. The two-turret SMK and T-100, as well as the single-turret KV, formed a company of heavy tanks, the commander of which was a 2nd rank military engineer I. Kolotushkin. On December 10, 1939, the company arrived at the front, where it was attached to the 90th tank battalion of the 20th heavy tank brigade.
The first battle of the SMK took place on December 17, 1939, the tank was used to attack the Finnish positions in the area of the Hottinen fortified area, where the "Giant" bunker was located, which was also equipped with artillery weapons in addition to machine guns. The battles showed that the Finnish 37-mm anti-tank guns "Boffors" can do nothing for the new Soviet tank. On the third day of the fighting, the SMK broke into the depths of the Finnish fortifications, moving at the head of a column of heavy tanks. At a fork in the Kameri-Vyborg road, the tank ran into a pile of crates, under which was a homemade land mine or anti-tank mine. A powerful explosion damaged the sloth and the track of the tank, tore off the transmission bolts, the bottom was bent by the blast wave. The damaged SMK covered the T-100 for some time, but the crew was never able to repair the blown up tank and the SMK had to be left in the place where it was blown up, while its crew was evacuated.
The loss of an experienced heavy tank caused a violent and very harsh reaction from the head of ABTU D. G. Pavlov. By his personal order, on December 20, 1939, a detachment was formed specifically to save the secret tank as part of the 37th engineer company and the company of the 167th motorized rifle battalion, two guns and 7 medium T-28 tanks were assigned to the detachment. The formed detachment managed to break through the line of Finnish nadolbov to 100-150 meters, where it was met by dense artillery and machine-gun fire of the enemy. An attempt to tow a 55-ton SMK with the help of a 25-ton T-28 ended in nothing, and the detachment, having lost 47 people killed and wounded, was forced to return to positions without following the order.
As a result, the tank stood at the site of the explosion until the moment when the Soviet troops managed to break through the Mannerheim Line. Specialists were able to inspect it only at the end of February, and the evacuation of the damaged vehicle was carried out at the beginning of March 1940, the tank was towed using 6 T-28 tanks. The SMK was taken to the Perk-Järvi railway station, where new problems arose - there were no cranes at the station that could lift the tank. As a result, the car was literally taken apart and loaded onto separate platforms for shipment back to the factory. On the instructions of ABTU, the Kirov plant was supposed to restore a heavy tank during 1940 and transfer it to Kubinka. But for unknown reasons, the plant did not start these works until the beginning of the Great Patriotic War. At the same time, parts and parts from the QMS lay in the factory yard, after the end of the war they were sent to be melted down.
The performance characteristics of the SMK tank:
Overall dimensions: body length - 8750 mm, width - 3400 mm, height - 3250 mm, ground clearance - 500 mm.
Combat weight - 55 tons.
Reservations - from 20 mm (hull roof) to 75 mm (hull forehead).
Armament - 76, 2 mm L-11 cannon, 45-mm 20K cannon, 4x7, 62-mm DT machine gun and one 12, 7-mm DK machine gun.
Ammunition - 113 rounds for the 76-mm gun and 300 rounds for the 45-mm gun.
The power plant is a 12-cylinder carburetor engine AM-34 with a capacity of 850 hp.
Maximum speed - 35 km / h (highway), 15 km / h (cross country).
Cruising range - 280 km (highway), 210 km (cross country).
Crew - 7 people.
