T-34 medium tank

During the Second World War, the T-34 was the tank that more influenced the German tank projectists and, in turn, this one originated from the work of Walter Christie. Thus, it can be said that this American engineer had a huge influence in the design of armored vehicles, which was not in proportion with his personal achievements in that field. Taking as starting point the BT series of fast tanks, developed in the Soviet Union - based on the M 1928 projected by Christie in his homeland - by Soviet projectist Mikhail Koshkin, in cooperation with Aleksandr Morozov and Nikolai Kucherenko in the factory of the Komintern in Kharkov, it was decided to build a 20-ton tank. This one, called A-20, had the capability designed by Christie for marching conventionally with tracks or marching without them like a conventional wheel vehicle. In about thirty minutes the crew of a "convertible" tank could remove the tracks and engage a chain drive from the drive sprocket to the rearmost road wheel on each side, allowing the tank to travel at higher speeds on roads. In this mode the tank was steered by pivoting the foremost road wheels like in conventional wheel vehicles. Other characteristics of the A-20 were a sloped armor in both the hull and the turret (this was the first one of the so called "Shellproof Tanks"), an L/46 45-millimeter cannon and a powerful and very reliable 450-horsepower Diesel engine, with which the tank was capable of reaching a speed of 65 kilometers/hour. In fact, this early tank already anticipated all the main features of the future T-34.

The A-20 was clearly superior to every rival model in everything except its cannon, so it was decided to replace that weapon by an L/26.5 76.2 millimeters short cannon. This new version of the tank was known as the A-30 and it started to be produced in 1939. Koshkin was not convinced about the usefulness of a tank marching without tracks. Such feature was found of little practical use in a country with few paved roads, it consumed space and added needless complexity and weight to the tank. The system was deemed as not worthy of the limitations that it imposed to the wheel ensemble, specially regarding the width of the tracks. In the next model, the A-32 - later renamed as T-32 -, this system was not installed. In this way the tank could be equipped with wider tracks that posed less ground presure, improving so traction. The T-32 was very similar to the A-20 and the A-30, except in that it had five wheels on each side instead of four, and these still were large enough to not require return rollers. The T-32 was slightly slower than the previous models but it was better armed and armored. Koshkin believed that this one was the best tank and the one that would allow a greater development. Consequently he used it as basement for the project of the T-34. With an armor thickess increased to up to 45 millimeters and with a somewhat more powerful engine, the prototype of the T-34 rolled for the first time in the late January 1940. In the beginning of February, two of the first T-34 produced undertook a long trials march under the personal supervision by Koshkin. They followed the route Kharkov-Moscow-Smolensk-Kiev-Kharkov. In Moscow the tank was shown to the High Staff in the Red Square. But in this travel Koshkin contracted pneumonia and he had to be interned in a hospital, where he would die the 26th September.


T-34/76C. Crew: 4; length: 7.08 meters; width: 2.9 meters; height: 2.45 meters; armor: 14-45 millimeters; engine: Diesel 500 horsepower; operational range: 450 kilometers; speed: 50 kilometers/hour; armament: one 76.2-millimeter cannon and two 7.62-millimeter machine guns.

Morozov took the command as project manager and put the tank into production. This one was equipped with a longer cannon, the L/30.5 76.2-millimeter cannon, which achieved a muzzle speed of 610 meters/second. Such velocity was enough to allow its piercing projectiles weighing 6.25 kilograms to perforate a 55 millimeters thick armor plate at normal distances and angles of incidence, and put out of action the contemporary PzKpfw III and PzKpfw IV from twice that distance and from the front. Two Degtyarev 7.62-millimeter machine guns were mounted: one in the frontal glacis of the hull and the other co-axial with the cannon. The tracks were wider than in any other tank of that time; they ran around an unequally spaced double-wheel ensemble, whose coil-spring suspension was installed inside the hull, allowing the T-34 to roll in conditions in which its opponents would get stuck. This modified Christie suspension allowed for high speed in cross-country and it waspresent in all the Soviet tanks until the T-62. Tanks fitted with this type of suspension were characteristic by their large wheels and absence of return rollers. The 615 liters of fuel - a fourth part of which were carried in an external tank that could be jettisoned when depleted - and the 500-horsepower V-12 Diesel engine granted this tank a considerable operational range of about 450 kilometers and a low risk of fire. The overall design of the tank benefited serial production and easy maintenance, as well as reparations in the battlefield. The majority of the mechanical elements of the tank, following the norms of the Red Army about standardization, were interchangeable with the ones from the KV heavy tanks. All of this made the T-34 to be an extraordinary tank, already since its initial version, which was constantly improved as the war progressed. Still, it had obvious defects. The final step in the transmission was prone to failures, a problem that was soon fixed with a remodelation. There were also problems with the turret. The commander's hatch was too large and it opened in reverse way, with the hinges in the fore part, while the turret, with a characteristic welded cradle for the cannon, was very small and had a "shot trap" cavity under the protruding rear part.

The first series T-34 tanks were delivered to the Red Army in June 1940 from the factories in Kharkov, Leningrad and Stalingrad, albeit that year only a total of 115 units were produced. Some of them were sent to Finland to carry combat trials, but they arrived too late to take part in the operations. When Hitler attacked the Soviet Union in June 1941, the factories at Kharkov and Leningrad were considered as vulnerable and hence transferred, along with the most part of the Soviet strategic industries, to locations east of the Ural Mountains. The tank factories were reallocated in Chelyabinsk, where in combination with the already existent tractor factory, they turned into "Tankogrado", where it would be concentrated the production of Soviet tanks until the dismemberment of the Soviet Union in the early 1990s. In the time of the invasion 1225 tanks T-34 had been built. The T-34 entered combat for the first time the 22nd June 1941 near Grodno in Belarus, constituting an unpleasant surprise for the Germans. However, in the Battle of Moscow, where 1853 of them were assigned to the fighting units, many of them were destroyed. In 1941 the tank crews of the Wehrmacht had to see how the new T-34, with its low profile and sloped surfaces, was a really difficult target for the cannons mounted in their tanks. Only towed anti-tank guns like the famous 88 millimeters Flak or the 75 millimeters Pak 40 could destroy the T-34 without trouble. In that year, none of the German tanks could compete against the T-34, either in firepower, protection or reliability. Due to the alarming situation, German generals insisted in the necessity of having the new Tiger and Panther tanks on the battlefield as sooner as possible. These two tanks were clearly superior to the T-34 in firepower and mostly in protection, but they suffered from inferior reliability, which also delayed their entry into service. The first Tiger tank would not enter service until December 1942 and the first Panther until mid 1943. However, the negligible organization of the Red Army in 1941 greatly helped the Germans in their fight against the new tank. The first T-34 tanks suffered from the absence of radio equipment - employing signal flags instead -, bad strategy in their formations and bad training in their crews. It was not rare to find abandoned T-34 tanks that had entered the deep mud only to get stuck there. Germans made operative use of many, if not all, of the captured T-34 tanks, being these greatly appreciated, and surely better exploited, by their new crews.


T-34/76D, version that entered service in May 1942.

The first variant of the T-34 was called in the western world the T-34/76A and it remained in production until 1942. In that time it was already available a new version of the cannon Model 1939, the more powerful Model 1940 F34. Its barrel had increased its length up to 41.2 calibers and, consequently, the muzzle speed had increased up to 680 meters/second. Besides the new cannon, the T-34 acquired as well a heavier armor and a turret built in cast steel, becoming so the T-34/76B. In that year were produced a total of 5000 units. In 1942, the T-34/76C started to appear, with a thicker armor, redesigned turret hatch and other improvements. That year the production reached 10000 units and it did not descend from that number until the end of the war. In 1943, there was a revision of the original model that improved it so much that it allowed the installation of a much more powerful cannon, the 85 millimeters D-5T85. However, it was decided to continue as well the development of the T-34/76. When it appeared the variant T-34/76D, it had a new turret, hexagonal, welded and larger than the previous one; it was clearly better, since it provided a much needed inner space and it removed the rear protrusion that was potentially very dangerous. The T-34/76E was very similar but with a taller commander's cupola, while the T-34/76F had the same turret, but built in cast iron instead of welded plates. To allow the installation of the much larger 85-millimeter cannon, the improved T-34 required a different turret. Krylov, who had replaced Morozov as project manager, choose one that served as well for the heavy tank KV-1 which had been started to be built almost at the same time than the first T-34. The new turret was much more comfortable and it had space for a fifth crew member that relieved the commander from loading the cannon, task that distracted him from his tactical role.

The 85-millimeter cannon was in every aspect equivalent to the KwK 36 88-millimeter cannon installed in the Tiger tanks. The cannon, in this first version, had a barrel 51.5 calibers long, fired 9.36-kilogram projectiles and had a muzzle speed of 792 meters/second. The improved cannon ZIS-S53 that replaced it had a barrel 3.1 calibers longer and a muzzle speed of 800 meters/second, which allowed to perforate a 100 millimeters thick armor plate at a distance of 1000 meters. In successive modifications, the radio was moved from the hull to the turret, new gunsights were installed, the commander's cupola was improved, ventilators were added before and after the turret, and smoke generators were fitted as well, which electrically detonated MDSh canisters. After the war, more improvements would arrive: improved engine V-2-34M, new wheels, improved ventilation and lubrication, battery generator, improved radio and installation of infrared vision, among others. The T- 34/85, as it was called the improved tank, entered production in December 1943 and, in the first month, the factory at Tankogrado produced about 300 units. In 1944, 11000 more were produced and another 10000 before the end of the war. It was estimated that, subsequently and until 1964, were produced at least other 10000 units. The T-34/85 remained in frontline service with the Red Army and with the armies of countries of the Warsaw Pact until well into the 1950s, when it was replaced by the T-54 and destined exclusively to training; after more than 50 years it could still be seen in the armed forces of some Third World countries. During the Second World War there were T-34 tanks of the two main types that were reconverted into flamethrower tanks. Others were modified for recovery of armored vehicles, either by simple suppression of the turret or by adding a crane and a windlass. After the war, some T-34 were equipped with bulldozer blades and minesweeper rollers; there were some, serving with the Czech Army, that were reconverted in bridge-laying vehicles. Some T-34 in Syria were remodeled as self-propelled howitzers with a 122 millimeters D-30 howitzer installed in the turret. In North Vietnam some T-34 were remodeled by installing in them turrets fitted with twin 37-millimeter anti-aircraft cannons.


The inner world of an early T-34/85 from the time of the Second World War.

Specifications for T-34/76D



Specifications for T-34/85





Article updated: 2014-12-25

Categories: Tanks - World War Two - 20th Century - [General] - [General]

E-mail:

Website: Military History

Article submitted: 2014-06-25