IS tank family

Iosif Stalin tank
IS-2 model 1943 (more modern fenders added) (foreground) and IS-3 (background) at the Great Patriotic War Museum, Minsk, Belarus
TypeHeavy tank
Place of originSoviet Union
Service history
Used by
  • Soviet Union
  • China
  • Cuba
  • Czechoslovakia
  • East Germany
  • Hungary
  • Egypt
  • Poland
  • North Korea
Wars
Production history
Designer
Designed
  • 1943 (IS-2)
  • 1944 (IS-3)
  • 1944–45 (IS-4)
ManufacturerKirov Factory, UZTM
Unit costIS-2: 264,400 rubles
Produced
  • 1943–44 (IS-1)
  • 1944–45 (IS-2)
  • 1945–47 (IS-3)
  • 1947–49 (IS-4)
No. built
  • 207 (IS-1)
  • 3,854 (IS-2)
  • 2,311 (IS-3)
  • 250 (IS-4)
  • 6 (IS-7) (prototypes)
Specifications (IS-2 Model 1944)
Mass46 tonnes (51 short tons; 45 long tons)
Length9.90 m (32 ft 6 in)
Width3.09 m (10 ft 2 in)
Height2.73 m (8 ft 11 in)
Crew4

Armor
Hull front: 120 mm
Lower glacis: 100 mm at 30° angle
Turret front: 100 mm (rounded)
Mantlet: 155 mm (rounded)
Hull side: 90–130 mm at 9-25°
Turret side: 90 mm at 20° angle
Main
armament
D-25T 122 mm gun (28 rounds)
Secondary
armament
DShK, 3×DT (2,079 rounds)
Engine12-cyl. diesel model V-2
600 hp (450 kW)
Power/weight13 hp/tonne
Suspensiontorsion bar
Fuel capacity820 L (180 imp gal; 220 US gal)
Operational
range
  • Road:
    240 km (150 mi)
  • Cross-country:
    180 km (110 mi)
Maximum speed37 km/h (23 mph)

The IS tanks (Russian: ИС) were a series of heavy tanks developed as a successor to the KV-series by the Soviet Union during World War II. The IS acronym is the anglicized initialism of Joseph Stalin (Ио́сиф Ста́лин, Iosif Stalin). The heavy tanks were designed as a response to the capture of a German Tiger I in 1943. They were mainly designed as breakthrough tanks, firing a heavy high-explosive shell that was useful against entrenchments and bunkers. The IS-2 went into service in April 1944 and was used as a spearhead by the Red Army in the final stage of the Battle of Berlin. The IS-3 served on the Chinese-Soviet border, the Hungarian Revolution, the Prague Spring and on both sides of the Six-Day War. The series eventually culminated in the T-10 heavy tank.