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IS-3 Heavy Tank

Heavy tank "Joseph Stalin - 3" (abbreviated IS - 3) - the last Soviet tank, adopted during the Great Patriotic War, but practically did not participate in hostilities. The first experimental batch of heavy tanks IS-3 left the factory workshops in May 1945. Before production ceased in mid-1946, 2,311 units were manufactured. Of these, until the end of World War II - 29. This combat vehicle is often considered one of the first post-war Soviet tanks. The abbreviation IS stands for "Joseph Stalin" - the official name of the series of Soviet heavy tanks produced in 1943-1953. Index 3 corresponds to the third production tank model of this family. The constructive solutions incorporated in the IS-3 had a huge impact on the further development of heavy tanks, which will be used in the design of the last Soviet serial heavy tank IS-8.

After the end of the Great Patriotic War, the Red Army completed its battles with a significant number of heavy IS-2s; in addition, in 1945 a new heavy IS-3 tank was adopted for its armament. On September 7, 1945, a parade of allied troops took place in Berlin in honor of the end of World War II. Then the IS-3 was demonstrated for the first time, which made a real sensation. The tank had hull and turret shapes that were very unusual for their time. The cast turret had a flattened spherical shape, the walls of the turret were made of variable thickness - from 75 to 230 mm. An anti-aircraft machine gun was mounted on the roof of the turret, which allowed both the loader and the commander to fire at the aircraft. A 122 mm tank gun and a coaxial DT machine gun (Degtyarev tank, 7.62 mm) were mounted in a cast mask. The bow of the hull looked unusual, it had a ship-like shape, which the designers jokingly called the "pike nose".

The IS-3 was a game-changer. The Soviets had developed a tank that was far more advanced than anything in the American and British arsenals. The message was loud and clear: the new Soviet IS-3 represented the first volley in the “action-reaction” tank-development cycle that became a defining characteristic of the Cold War. More recent assessments of this popular tank argue that the IS-3 has historically been overrated. When developing the project of the IS-3 tank, the conclusions of the commission were taken into account which examined the combat damage received by tanks during the Battle of Kursk in front-line conditions. Attention was drawn to the massive defeat of the frontal elements of the hull and turret. Therefore, it was decided to work out on the basis of the IS-2 tank a new design of the turret and hull to give them a streamlined shape and sharply differentiate the armor protection. As a result of design work, the inclination of the welded sheets, especially in the front of the hull, was brought to the maximum possible.

Unfortunately, it soon became clear that the IS-3 was unsuitable for service in peacetime - their reliability and the lifetime of the mechanisms turned out to be extremely low, whereas in peacetime the tank had to be operated for years and not for several weeks (until its destruction in combat ) as it was during the war. As a result, already in 1946, the production of the IS-3 was completed, without having had time to turn around in full force, and all the tanks that had already been released underwent modernization under the program for elimination of design flaws.

For the rest of the 1940s and 1950s, the IS-3 was photographed and paraded as often as possible by the Soviets, and reports were released to the public that highlighted the tank’s participation in various Soviet-army exercises. As time went by, however, all this attention led to more information being learned by American and NATO intelligence organizations. This information included reports that the cutting-edge Soviet tank was suffering from important mechanical and structural problems. These problems ranged from production hull welds being stressed to the point of failing and engine-reliability issues to a series of problems resulting from mounting such a large and heavy main gun in such a small turret.

Production of the IS-3 tanks with an improved electric drive for turning the turret was organized in accordance with the resolution SNK of the USSR No. 3217-985 of December 30, 1945 (order of the NKTP No. 8 of January 17, 1946). The design of the electric drive was designed by ChKZ in cooperation with Plant No. 255 of the People's Commissar-Transmash according to the concept of Leonardo in combination with the commander control device of the turret, proposed by Experimental Plant No. 100. The installation of the drive on the first 50 tanks of the IS-3 was carried out by the Chelyabinsk Shipyard in March 1946. From April 1 of the same year, the electric drive of the turret with commander target designation was installed on all manufactured vehicles.

Work to improve the security of the tank on the battlefield was carried out in the direction of enhancing its protection against cumulative projectiles (grenades) and anti-mine resistance, as well as creating a fire extinguishing installation (PPO system). In order to increase the mobility of the machine, research has been launched to improve the power plant (increasing the reliability of engine operation, cooling system efficiency, testing and testing air cleaners with automatic dust removal, and steam-dynamic heater). They began to create an electromechanical transmission (“Object 707”) and high-durability tracks — at least 3000 km. During the operation of the IS-3 tanks produced in 1945, the engine overheated in the conditions under which the engines of the IS-2 tanks worked normally. The comparative ground tests of the IS-2 and IS-3 tanks carried out at the end of 1945 confirmed this fact.

The cooling system of the engine of the IS-3 differed from the cooling system of the IS-2, mainly by the design and dimensions of the air duct (especially the cooling air inlet and outlet), as well as the design of air-oil radiators, and the ChKZ design bureau introduced a number of changes to the engine cooling system design. of the IS-3 tank and introduced them into serial production on tanks manufactured in 1946. Comparative ground tests of the vehicle with mileage, which took place in the same year, confirmed the effectiveness of the measures taken.

In 1945, “for the creation of the design of the IS-1 tank and the fundamental improvement of the existing tank”, the Stalin Prize of the 1st degree was awarded to a group of designers from the Kirov and Experimental Plants: N.L. Dukhov, L.S. Troyanov, M.F. Balzhi, G.V. Kruchenykh, V.I. Torotko, several hundred tank builders were awarded orders and medals. The IS-3 entered service with the heavy self-propelled tank regiments of the Soviet Army, where they were operated until the 1970s. In the IS-3 tanks of the last year of production, unlike the vehicles of the first series, two air-oil radiators were installed in front of the fans, instead of four air-oil radiators mounted behind the fans. This made it possible to obtain large internal sections of the air path of the engine cooling system by reducing the height of the internal fuel and oil tanks. Exhaust pipes have completed a streamlined shape and improved the configuration of the collectors of air fans. In addition, recommendations were given on placing the landing on a vehicle in summer (at an ambient air temperature of +20 - 30 ° C), since its location on the roof of MTO (cooling air inlet louvers) under heavy engine loads could lead to its rapid overheating.

One of the major defects of the machine was the lack of rigidity of the body in the area of MTO, which led to a violation of the alignment of its units. So, for example, not a single tank of 1946 release passed the warranty tests for 300 and 1000 km of run. In the same year, a stream of complaints about the failure of the engines followed from the troops at ChKZ. On the tests of six IS-3 tanks, the malfunctioning of the vertical roller drive of the fuel pump of the B-11 engine was identified due to the destruction of the ball bearing cage of this roller. As a result, ChKZ carried out appropriate measures to improve the reliability of its work (the ball bearing was replaced with a plain bearing on the engines of the subsequent release).

In addition, during the long-term operation of machines, cracks began to appear not only in the welds of the hull, but also in the casings of the cast turrets (in the area of the gun installation, as well as in the zygomatic and other parts). The low strength of the welded joints of the IS-3 hull was also confirmed by the test results by shelling in 1946 at the NIIBT test site of five hulls made by the Chelyabinsk plant No. 200 and the Uralmash plant. For a more detailed study of the defects of the IS-3 tanks, the plant sent qualified units and operators to the military units of the brigade.

Modernization of the IS-3 tanks coming from military units was carried out at ChKZ (from 1950 to 1953) and LKZ (from 1950 to 1954) in accordance with Resolution of the Council of Ministers of the USSR No. 4871-2121 of December 12 1950. Modernization of machines during this period by manufacturers was carried out without changing the brand of the machine.

Based on the results of tests of six IS-3s in the spring of 1952, the commission concluded that it was possible to resume acceptance of tanks of this type LKZ and ChKZ and the need to replace on all previously released machines rigid serial clutch of the engine fuel pump to the elastic coupling ChKZ-45. As a result, the acceptance of tanks at the plants (as well as the V-11M diesel at ChKZ) was resumed from May 30, 1952.

In December 1952, tests of three IS-3 tanks with high-powered engines (419 kW (570 hp)) were carried out at the NIIBT test site. However, these tests were stopped due to the failure of transmissions. One gearbox was restored by by means of the landfill, and two boxes required replacement with delivery from the LKZ by January 10, 1953. However, the question of installing IS-3 tanks in UHC tanks with increased power remained open.

The Soviet tank division at full strength had about 8,000 men and 2,300 major items of equipment, including 310 medium tanks, 80 APCs, and 60 artillery pieces. Soviet airborne divisions had about 6,000 men and 1,000 major items of equipment. A few tank divisions, carried as "heavy tank divisions", were smaller (lacking a motorized rifle regiment) and contained heavy tanks (T-10 and JS-3). Heavy tanks were still observed in some tank divisions, but by 1970 it was not certain whether a "heavy tank division" exists as a separate type.

In June 2014, anti-government separatists in Ukraine decided to include an IS-3 Stalin heavy tank built in 1946 that was anchoring a Ukrainian monument to the Great Patriotic War in their struggle against federal forces. After some coaxing from local mechanics and the belching of a lot of smoke from the engine, the pedestal-mounted tank started up. The IS-3 was driven off the monument platform and assumed new duties with the separatists for six months or so. According to separatist forces, the IS-3 was used in battle June 30, 2014. Eventually, Ukrainian federal forces regained control of the local area and recaptured the tank. This infamous IS-3 is now on display near Kiev at Ukraine’s National Military History Museum.

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Page last modified: 13-09-2021 17:24:09 ZULU