Length 6.75 m
Width 3.32 m
Height 2.71 m
Weight 45+ tonnes
Armour and armament
Armour 90 mm
Main armament M-10 152 mm howitzer
Secondary armament 4×DT machine guns
Power plant 12-cyl. diesel model V-2
600 hp (450 kW)
Suspension Torsion bar
Road speed 35 km/h
Power/weight 13 hp/tonne
Range 335 km
After disappointing results with the multi-turreted T-35 heavy tank, Soviet tank designers started drawing up replacements. The T-35 conformed to the 1920s notion of a 'breakthrough tank' with very heavy firepower, but poor mobility and armor protection. The Spanish Civil War demonstrated the need for much heavier armor on tanks, and was the main influence on Soviet tank design just prior to World War II.
Several competing designs were offered, and even more were drawn up prior to reaching prototype stage. All had heavy armor, torsion-bar suspension, wide tracks, and were of welded and cast construction. One of the main competing designs was the SMK, which lowered the number of turrets from the T-35's five to two, mounting the same combination of 76.2 mm and 45 mm weapons. When two prototypes were ordered though, it was decided to create one with only a single turret, but more armour. This new single-turret tank was the KV. The smaller hull size and single turret enabled the designer to add more armor while keeping the weight within manageable limits.
When the Soviets entered the Winter War, the SMK, KV and a third design, the T-100, were sent to be tested in combat conditions. The heavy armour of the KV proved highly resilient to Finnish anti-tank weapons, making it more effective than the other designs. It was soon put into production, both as the original 76-mm-armed KV-1 Heavy Tank and the howitzer-mounting assault gun, the KV-2 Heavy Artillery Tank.
The KV-2 Heavy Artillery Tank's 152-mm howitzer was housed in an enormous turret.
The 45-ton KV outweighed most other tanks of the era, being about twice as heavy as the heaviest contemporary German tanks. The KV's strengths included armor that was impenetrable by any tank-mounted weapon then in service except at pointblank range, good firepower, and good floatation on soft ground. Along with these strengths, its flaws were quite serious. It was very slow and difficult to steer. The transmission was unreliable. The ergonomics were poor, with limited visibility and no turret basket. Later, by 1942, when the Germans were fielding large numbers of long-barrelled 50-mm and 75-mm guns, the KVs armor was no longer invincible, and other flaws came to the fore. While its 76.2 mm gun was adequate, it was the same gun as carried by smaller, cheaper T-34 medium tanks. It was much more difficult to manufacture and thus more expensive than the T-34. In short, its advantages no longer outweighed its drawbacks.
When Operation Barbarossa began, the Red Army was equipped with 639 KV-1s. So effective was its armour that the Germans were incapable of destroying it with their tanks or anti-tank weapons and had to rely on air support and anti-aircraft artillery (flak) to knock them out. At one point, a large German armoured group was delayed for 2 days by a single KV-2 near Ostrov.
(Low poly, Game-Ready!)