Russian Heavy Tanks
Armament: 1 x 76.2mm L16 gun , 2 x 45mm 20K guns and 3 x 7.62mm MG's.
Armour: 35mm.
Weight: 44 tons.
Speed: 18mph (30kmh) on road and 12mph (20kmh) cross country.
Range: 93 miles (150km) on road and 58 miles (87km) cross country.
Crew: 10, commander, commanders asssistant, 3 x gunners, mechanic, driver and 3 x Mg gunners.
In August 1932, work began on a new 35-ton heavy tank.
The main turret, similar to the one used on the T-28, was armed with
the 76.2mm KT tank gun and two further turrets, one facing to the rear
of the vehicle were mounted with 45mm 20K guns. The transmission of
the T-35-1 consisted of a petrol engine, a friction clutch, a gearbox
and a well-designed pneumatic system. However early flaws in the transmission
system saw an improved version introduced in February 1933. A standardized
turret, new tank engine, gearbox and an improved transmission were installed
and production began in August 1933 as the T-35A.
The new vehicle featured a longer chassis, smaller turrets and an improved
hull. The vehicle still suffered from design problems. The tracks of
the tank were too fragile and the M-17 engine often overheated. The
vehicles five turrets were set up in two tiers and provided considerable
firepower with one 76.2mm gun, two 45mm 20K guns and three machine-guns.
The crew compartments were separated from each other and cramped. This
made communication inside the vehicle difficult. Visibility for the
crew from within the vehicle was also poor. The layout of the turrets
also resulted in an excessively high profile and decreased the vehicles
mobility on the battlefield.
In 1937, the T-35 was modernised. The gearbox, side clutches, electrical
equipment, drive shaft and oil tank were improved and engine silencers
were installed inside the vehicle. These changes greatly increased the
poor reliability of the vehicle. Under combat conditions the armour
protection of the T-35 was found to be inadequate, but because the vehicle
was already too heavy, it was unrealistic to increase its armour protection
further.
Production of the vehicle ended in 1939 and the majority of vehicles
were lost to mechanical breakdown during the first few weeks of the
campaign.
Armament: 1 x 122mm D-25T gun (28 rounds) 1 x 12.7mm MG and 3 x 7.62mm MG's.
Armour: 120mm.
Weight: 49.5 tons.
Speed: 23mph (37kmh) on road and 17mph (26kmh) cross country.
Range: 240miles (360km) on road and 160miles (240km) cross country.
Crew: 4, commander/Mg gunner, gunner, driver and Mg gunner.
The JS-1 was a new design based on the KV-13 prototype, which had originally been introduced in May 1942. Many of the components of the KV-1s were incorporated in the chassis, while the turret was similar to that on the KV-85, but the hull and interior were completely redesigned.
The JS-2 meanwhile, although identical in design to the JS-1, was to be fitted with the 122mm Tank Cannon D-25T gun. The gun was fitted with a T-shaped muzzle brake design, which was intended to minimise any dust plumes due to firing. The gun also featured a semi-automatic breech, which allowed an increased rate of fire from 1.5 shots per minute to 2 shots per minute.
Both vehicles performed well in trials, weighed less than the KV-1s, could achieve higher speeds, had better armour protection and had equal or better armament.
However, the trials also revealed that the chassis and engine transmission were inadequate. It was also noted that when moving over soft ground the tanks experienced high rolling resistance, due to their treads flexing into the space between the road wheels, which led to them easily being thrown. This was remedied with the addition of an extra road wheel to compensate for the increased distance between the second and third road wheels. All these changes resulted in an increase of the tank's weight to 44 tons and a reduction in its mobility. Another failure that was found with the JS-2 was its limited ammunition stowage, it could only carry twenty-eight rounds.
Production of the JS-1 vehicle began in October 1943, while production of the JS-2 began in December. However, production of the JS-1 ended in January 1944 and from then on all further production was of the JS-2 type.
When the JS-2 entered combat, it was found that when the vehicle was hit, considerable splintering and fragmentation occurred inside the turret, injuring the crew. In February 1944 attempts were made to rectify this fault by increasing the armour tempering and redesigning the shape of the vehicle hull with a straightened glacis, sloped at 60°. Vehicles with the new improvements were introduced from May 1944 onwards. A further improvement introduced at the same time, was the fitting of a new turret with a widened porthole and improved armour protection on the tank's mantlet. The JS-2 remained in service throughout the remainder of the campaign.
