KV-1 Heavy Tank

Development history

DEVELOPMENT HISTORY

In October 1938, a group of undergraduate students from the Mechanisation and Motorisation Academy of the Red Army arrived at the Special Design Bureau No. 2 at the Kirov Factory in Leningrad in order to carry out their graduate project. The Design Bureau was engaged at that time in work on the three-turreted SMK tank – named after the murdered Bolshevik leader, Sergei Mironovich Kirov.  In connection with this, the arriving students proposed a draft project involving the same overall design of the SMK tank, but with only one turret. Numerous problems arose during the design process, however, including problems with the original planetary transmission.

At this time, trials were being conducted on the Czechoslovakian-built Skoda S-II-a tank, which the Red Army command intended to acquire. Several persons were sent to Kubinka from the Kirov Design Bureau in order to familiarize themselves with the Czech tank. As a result, a significant amount of interesting material made its way back to the Bureau. Work on the proposed design continued.

Commencing in December 1938, a gathering at the Main Defense Council began examining the design of the SMK tank, which was approved for production in a two-turreted variant. It was proposed that two prototypes be constructed for trials. Also attending the conference were the chief of Design Bureau No. 2, Zh. Ya. Kotin, and the director of the Kirov Factory, I. M. Zal'tsman. They proposed constructing a single-turreted tank in place of the second SMK prototype. It should be noted that military officials and designers during these years quarreled over the designation of medium and heavy tanks.

The military wanted multi-turreted monsters, while the design staff favoured simpler, single-turreted vehicles.  Time would tell who was correct. The Main Military Council took the decision to design and manufacture a tank corresponding to the technical specifications of the SMK.

Final confirmation of the technical specifications and authrorisation for the construction of the tank was approved by a order No. 45ss of the Committee of Defense of the Council of People's Commissars of the USSR on February 27th, 1941.

The Kirov Factory embarked upon the design process of the new tank, named the KV – after the Soviet Peoples' Commissar of Defense, Kliment Voroshilov, on February 1st, 1939. This was prior to the approval of its technical specifications. As a result, the preceding specifications regarding the SMK tank were used as the basis for the new tank. The basic design made use of the graduate project developed by the students from the Mechanisation and Motorisation Academy, who had been sent to work at Design Bureau No. 2 in March 1939, upon receiving their diploma.

Work on the tank proceeded quickly. On April 9th, a technical mock-up was approved and on September 1st, the tank was assembled and subjected to a driving terst.

The KV borrowed many of the design specifications of the SMK tank, including the armour scheme, design of optical sights, elements of the transmission and so on. A V-2 diesel engine was installed in the tank along with a standard gear box. The DK machine-gun was rejected in light of the technical specifications which envisioned two guns being mounted in the turret – a 76-mm and a 45-mm, which left no room for the DK.

On September 5th, the tank was sent to Moscow, where it was presented to government officials on September 23rd. On October 8th, the vehicle returned to Leningrad and was sent off for trials. The onset of the Soviet-Finnish War led to the suspension of the trials and the tank joined the 91st Tank Battalion, 20th Heavy Tank Brigade and was sent off to the front, alongside the SMK and the T-100, where it distinguished itself. Upon arriving at the front, the 45-mm gun was removed as it interfered with the crew's operations. On December 19th, Molotov signed Resolution No. 433ss of the Committee of Defense of the USSR, according to which the KV tank was accepted for the Red Army – this, after the test model had driven only 650 km! As a result of the combat trials, the decision was taken to equip four of the tanks from the first production batch with a 152-mm ML-10 howitzer. This development would lead to the KV-2 heavy assault tank. Prior to 1941, however, these two tanks had not received the designations KV-1 and KV-2 yet, and were known in more prosaic terms as ‛the tank with the large turret“ and ‛the tank with the small turret“.

By May 1940, the yearly production target for the KV was increased from 50 to 200 vehicles. The Armoured Department of the Red Army became anxious over the fact that the tank had not undergone full trials and that many defects had emerged among those vehicles already produced. The tank was ordered to undergo comprehensive trials, which began in May 1940 at Kubinka and near Leningrad.

As a result of distance trials of some 2648 kilometers, the tank was discovered to have significant problems involving the transmission, running gear and engine. The engineers from the Kirov factory suggesting calling a halt in production until the problems were ironed out.  This was at odds, however, with the decision of the Council of Peoples' Commissars and the Central Committee of the Party, that the production of the tanks undergo continual growth.

Thus, quality was sacrificed for quantity, which would be paid for in blood one year later. At the end of 1940, the original L-11 gun began started replaced by the F-32 gun, which became known as the KV-1 Model 1940.

The KV tank had a 600hp liquid-cooled V-2K diesel engine, which differed slightly from the V-2 engine employed in the T-34. In the spring of 1941, the decision was taken to install additional bolted-on armour after viewing German propaganda films. Thus appeared the tank which would receive the designation KV-1E (E — ekranirovanniy: lit. ‛with armoured screenings“), although this designation is the result of the later imagination of modern-day writers. At the time, the documented name of the tank continued to be the KV-1, with the occasional addendum -  «with additional armour».

Combat employment

COMBAT EMPLOYMENT

As of June 22nd, 1941, the Red Army possessed 693 KV tanks. In the 1941, the KV tank could destroy any tank the Wehrmacht had to offer, while remaining virtually unassailable to enemy tanks itself. This is corroborated by several accounts of solitary KVs holding up entire German units for a significant  period of time. Thus, one KV, having taken up a position on the motor road outside of Ostrov, halted the German advance along the road to Leningrad for a number of days. During this time, the crew of the KV succeeded in destroying 7 German tanks, a battery of anti-tank artillery, one 88 mm gun with its crew, along with several lorries and armoured personal carriers. The tank was eventually destroyed by an 88-mm anti-aircraft gun.

Nevertheless, numerous myths abound, focused mainly on the supposed invulnerability of the KV. Practically all of these myths arose at the hands of German commanders who had committed flagrant errors and attributed their failures afterward on the mythical Russian ‛wonder-tanks“. For example, the commander of the 4thPanzer Division, Freiherr von Langermann, reporting on the fighting near Orel states: «For the first time during the campaign in the East, in these battles the absolute superiority of the Russian 26 ton and 52 tons tanks over our Pz. Kpfw. III and IV was felt. The Russian tanks usually formed in a half-circle, open fire with their 7.62 cm guns on our Panzers already at a range of 1000 meters and deliver enormous penetration energy with high accuracy».

However, closer examination reveals that Langemann had committed serious errors which led to his division being attacked by Soviet tanks while in marching formation. A surprise attack of this sort could only have taken place if the divisional command had neglected carrying out reconnaissance and battlefield security. Coordinated reconnaissance in all directions would normally have provided ample warning of the enemy's positions, but this was not done. In order to conceal his mistake, Langemann began inventing the myth about the invulnerability of the Soviet tanks, belching out 'highly accurate' and 'enormously penetrative' fire from a kilometer's distance.

There are numerous such examples. Guderian, for instance, in Panzer Leader, refers to ‛the marked superiority of the T-34“ during the fighting at Mtsensk, yet Guderian's panzers had had repeated encounters with T-34s and KVs long before this. During these earlier encounters, however, everything had gone well. Guderian had even written, in a letter dated October 21, 1941, that ‛the Soviet T-34  presents a typical example of backward Bolshevik technology“ and according to the ‛great tank strategist,“ one only had to strike against its the weakly-armoured rear section. His reference to the ‛marked superiority of the T-34“ would occur later. Statistics regarding the losses of these tanks speak eloquently of the recurrent German efforts to paint over their own mistakes rather than the nature of KVs and T-34s as ‛wonder-tanks“.

Combat losses among KV tanks were primarily inflicted by the German 105-mm howitzers and 88-mm anti-aircraft guns. A rather significant number of KV tanks were lost due to non-combat causes, mechanical breakdowns being the chief culprit. Since the Red Army was retreating at the time, practically of these vehicles ended up as irrecoverable losses.

We may cite several such examples. Thus, during the fighting in August 1941, the 10th Tank Division, 15th Mechanised Corps, lost 56 of the 63 KV tanks it had on hand. Of these, 11 had been lost in combat, 11 went missing and 34 were abandoned by their crews due to mechanical breakdowns. In the 8th Tank Division, 43 out of 50 KVs were lost – 13 were knocked out, 2 became stuck in a swamp, and 28 were abandoned or destroyed by their crews due to mechanical failure.

Nevertheless, in July 1941, the first KV-1 Model 1941 rolled off the assembly lines. To the untrained eye, the most noticeable distinction was the new 76.2-mm ZIS-5 gun, but this was only one of numerous improvements in comparison with the preceding models of the KV.

New reinforced turrets started appearing on the tanks, although the required number of new turrets and guns were lacking and some of the vehicles left the workshops as before with welded turrets and F-32 guns. By 1942, all KVs were being equipped with ZIS-5 guns and for a time it was debated whether to install the F-34 gun initially developed for the T-34 medium tank. A new cast turret was also developed for both the KV and the T-34, which marked a considerable technical advance in production.

It has been a long-held belief that the Germans abruptly pursued the creation of their own heavy tank – the Tiger, as a result of having experienced the shock of encountering the Russian KV tanks. The truth, however, is that the Germans began work on the heavy tank that would eventually become the Tiger long before the war against the USSR commenced. Still, captured KVs were periodically made use of by the Germans on the Eastern Front. And in 1942, the German command even considered the possible employment of companies of captured KV tanks in the Mediterranean theater while planning the intended invasion of Malta.

In 1942, responding to the military, Soviet designers began developing a tank with lighter armour and a speed close to that of the T-34. The new tank received the designation KV-1s (skorostnoi: lit. ‛high-speed“).  A flame-thrower tank – the KV-8 – was also constructed on the chassis of the KV and was armed with a 45-mm gun. Further experimental vehicles included an artillery tank with an 85-mm gun (Object 220) and others.

The chief deficiencies of the KV tank were its weak mechanical reliability, poor crew ergonomics, and limited means of observation. The greatest problem, however, was poor training among the crews. Still, in skillful hands, the tank was capable of performing real wonders, supporting once more the thesis of our site that men wage war – not tanks. It was in a KV tank that Lieutenant Zinoviy Kolobanov (1st Tank Division) destroyed 22 German tanks in one engagement while Lieutenant Semyon Konovalov (15th Tank Brigade) destroyed 16 tanks and 2 armoured cars.

KV tanks series:

• KV-1 Heavy tank – weight: 46–48 tons; armament: 76-mm gun. Production model.
• KV-2 Heavy assault tank – armament: 152-mm gun. Production model.
• KV-220 Heavy breakthrough tank – weight: 63 tons armament: 85-mm gun. Experimental.
• KV-222 Heavy tank – armour: 90-105mm weight 51 tons armament: 76-mm gun. Experimental.
• KV-3 (Object 223) Heavy tank – weight: 75 tons armament: 107-mm F-42 gun (later – 107-mm ZIS-6 gun). Experimental.
• KV-4 (Object 224) Super-heavy breakthrough tank – weight:between 85 to 110 tons. Experimental.
• KV-5 (Object 225) Breakthrough and defensive support tank – weight: 100 tons armament: 107-mm ZIS-6 gun. Experimental.
• KV-6 (Object 226) Heavy chemical tank. Experimental.
• KV-7(i) (Object 227) Heavy turretless tank (Variant I) – one 76-mm and two coaxial 45-mm guns. Experimental.
• KV-7(ii) (Object 227) Heavy turretless tank (Variant II) – two 76-mm guns. Experimental.
• KV-8 Flamethrower tank. Production model.
• KV-9 (Object 229) Heavy assault tank – armament: 122-mm howitzer. Experimental.
• KV-10 (Object 230) Undefined designation referring to either the KV-1K rocket tank or an unfinished variant of the KV-85. Experimental.
• KV-11 (Object 231) Undefined designation. Planning stage.
• KV-12 (Object 232) Heavy chemical/flame thrower tank. Experimental.
• KV-13 (Object 233) A medium-speed, heavily-armoured tank. Experimental.
• KV-14 (Object 236) Heavy self-propelled gun known as the SU-152. Production model.
• KV-1S (Object 238) High speed variant of the KV-1 with lighter armour and new transmission. Production model.
• KV-8S (Object 238) KV-8 variant on a KV-1S chassis. Production model.
• KV-85 (Object 239) KV-1s with a JS-2 turret. Production model.