III. Heavy Tanks

October 07, 2003

***Tank speed here is maximal, range is given on byroads

1. T-35. (1933-39)
   1. T-35A (1933-35)
   2. T-35M35 (1935-37)
   3. T-35M38 (1938-39) with conical turret
2. KV
   1. KV-1M40 (1940-41)
   2. KV-1M41 (1941-42)
   3. KV-1S (1942-43)
   4. KV-2M40 (1940)
   5. KV-2M41 (1941)
   6. KV-8 (flame thrower tank)
   7. KV-8s (flame thrower tank)
   8. KV-85 (1943)
3. IS tanks
   1. IS-1 (IS-85)
   2. IS-2 (1944-45)
   3. IS-3 (1945-46)
4. Summary of IS-2's Tests
5. Remarks

1. T-35. (1933-39)

The first heavy tank of RKKA

1a. T-35A (1933-35)

• Weapon: 76.2 mm gun KT-28+2-45mm guns (M32) +6-7,62 machine-guns (MG)
• Armor: 50mm - front, 20mm-(tilted) front, 20mm-side and rear, 10mm shielding on trackguards, 20mm on all turrets.
• Speed: 28,9 km/h
• Range: 80-90 km
  

1b. T-35M35 (1935-37)

• Weapon: 76.2 mm gun KT-28+2-45mm guns (M32) +7-7,62 machine-guns (MG)

see 1a.

1c. T-35M37 (1937-38)

• Weapon: 76.2 mm gun KT-28+2-45mm guns (M32) +7-7,62 machine-guns (MG)
• Armor:70mm- front, (tilted areas) 20mm font (upper and lower inclined areas), 20mm-rear, 25mm-side 10mm-trackguards, 20mm-all turrets.
• Speed: 28,9 km/h
• Range: 80-90 km

Comments: Had increased armor and a more powerful engine. Data was assumed to be the same as for T-35M38 which differed only by the turrets' construction

1d. T-35M38 (1938-39) with conical turret

• Weapon: 76.2 mm gun KT-28+2-45mm guns (M32) +7-7,62 machine-guns (MG)
• Armor:70mm- front, (tilted areas) 20mm front (upper and lower inclined areas), 20mm-rear, 25mm-side 10mm-trackguards, 20mm-all turrets.
• Speed: 28.9 km/h
• Range: 80-90 km
• Number produced - 6

Total number of T-35 different modifications - 61 unit

Total number of T-35 in RKKA on Jan 01, 1941 - 56 units (in other sources-59 units)

Almost all (38) vehicles were used by 67th and 68th tank regiments (34th Tank Division/8th Mechinised Corps, South-Western front). Some vehicles were in Kharkov under repair and were used in October 1941 as immovable pillboxes. 2 vehicles were seen in "documentary" movie - "The Battle for Moscow" but actually had never been used there.

All T-35's of the 8th Tank Corps were lost before July, 09'41.

Full list of T-35 losses in combat:

67th Tank Regiment:

• #0200-9 - was destroyed in June, 30
• #399-48 - was destroyed near Belo-Kamenka village, June,30
• #148-39 - was destroyed near Verba village, June,30
• #288-14 - unknown lost near Zapit village, June,28
• #220-25 - was destroyed near Ptichje village, June,30
• #988-16 - was destroyed near Ptichje village, June 30
• #339-68 - was destroyed by shells near Brody town, June, 30
• #200-0 - was destroyed near Ptichje village, June,30

By July, 1-2 ~5 units were lost due to technical breakages (i.e. in theory they could been used in fights earlier)

68th Tank Regiment:

Lost none from enemy fire

On July. 1-9 some 7-10 machines were lost due to technical failures

Two self-propelled guns were made based of T-35's hull (SU-14BR2 and SU-14-2) Both were used in the Battle for Moscow. They had both 50mm front armor, 30mm on the sides. Speed 15km/h, Range from 80 to 100 km

2. KV

2a. KV-1M40 (1940-41)

• Weapon: 76.2 mm gun L-11 +4-7,62 machine-guns (MG)
• Armor: 75 mm all
• Speed:35km/h
• Range: 90-180 km

Comments: in 1941 some units with spark-ignition engines were built

The first KV-1 was used in the Winter War (1939-40)

2b. KV-1M41 (1941-42)

• Weapon: 76.2 mm gun (F-32 or ZIS-5) +4-7,62 machine-guns
• Armor: 75 mm all
• Speed:35km/h
• Range: 90-180 km

Comments: Had screened modifications (additional screens on front sheet and turret).

Total amount produced (all KV-1 modifications) - 3486 units

On June 22,1941 in RKKA - 639 units. Were widely used on all fronts until August,42. Most KV-1's in 1941 were used in the defense of Leningrad. Last KV-1 was seen in 1944 on the Karelian front

2c. KV-1S (1942-43)

• Weapon: 76.2 mm gun (ZIS-5) +3-7,62 machine-guns
• Armor: 75 mm front, 82mm gun's mask and turret's front, 75mm-turret sides and rear, 60mm- side and rear (in other sources even 40mm)
• Speed:43km/h
• Range: 80-160 km
• Produced - 1087 units

2d. KV-2M40 (1940)

• Weapon: 152.4mm howitzer (MT-1) +4-7,62 machine-guns
• Armor: 75 mm all;
• Speed: 32km/h;
• Range: 145 km;
• Produced - 24 units

Comments: Almost all (19 units) were concentrated in the 2nd Tank Division in the Baltic region,

All were lost in June 1941.

See also KV-2 gallery

2e. KV-2M41 (1941)

• Weapon: 152.4mm howitzer (M-10) +4-7,62 machine-guns
• Armor: 75 mm all
• Speed: 35 km/h
• Range: 80-140 km
• Produced ~ 200 units (according to another source ~100)

See also KV-2 gallery

Comments for all KV-2: Were used in a tank divisions of mechanised corps (a few units in each). I also have information about their usage in separate battalions (15 units in each) in breakthrough tank divisions. Almost all of them were lost in the first months of 1941. Differed from KV-2M40 by turret's size and shape.

2f. KV-8 (flame thrower tank)

• Weapon: 45mm gun +4-7,62 MG + flame thrower
• Armor: front-110mm -75 mm other sides
• Speed: 35km/h
• Range: 160 km
• Produced - 102 units

Comments: First usage on summer 1942 on the Volkhov Front

2g. KV-8s (flame thrower tank)

• Weapon: 45mm gun +3-7,62 MG+ flame thrower
• No data
• Produced - 35 units

Comments: Produced on the base of KV-1S. Some data may be extrapolated from it.

25 units were made with the chassis of the KV-1S and turret from KV-8 + 10 original KV-8S (turret like KV-1S)

2h. KV-85 (1943)

• Weapon: 85mm gun (D-5) +3-7,62 MG
• Armor: Front-75mm, border-60mm, rear-40mm, turret-100mm
• Speed:34km/h
• Range: 80-180 km
• Produced - 143 units

see also KV-85 gallery

Comments on all KV: "KV" is an abbreviation of "Klim Voroshilov". He was a "Narkom" (minister) of defense for the USSR till 1940. In the troops one can heard the shorter name "Klim".

The KV's of the first series had very weak transmissions. Many tanks were lost to mechanical breakages. (about 50-60%)

3. IS tanks.(JS tanks)

Remark: IS is direct translation of Russian abbreviation. Also JS abbreviation can be seen in western sources. This origins from "Joseph Stalin" name of this tank. Both notations are correct.

3a. IS-1 (IS-85)

• Weapon: 85mm gun (D-5) +3-7,62 MG
• Armor: front-120mm, border-90mm, rear-60mm, turret-100mm
• Speed: 37km/h
• Range:120-135km
• Produced - 107 units 1943: Oct - 2, Nov-25, Dec-40,1944: Jan. - 40.

3b. IS-2 (1944-45)

• Weapon: 122mm gun (D-25) +3-7,62 MG May be equipped also with 1-12,7 anti-aircraft MG
• Armor: Front-120mm, border-90mm, rear-60mm, turret-100mm
• Speed: 35 km/h
• Range: 120-135km
• Produced: 3,385

Comments: Had some slight modifications.

Summary of IS-2's Tests:

Vulnerability to 88mm "Tiger" gun-1000-1200m (Front)

Vulnerability to 75mm "Panther" gun-900-1000m (Front)

Vulnerability to 75mm Panzer IV gun-300-400m (Front)

Vulnerability to 88mm - 1200-1500m (Side, inclined)

Vulnerability to 75mm Panzer IV-600-700m (Side, inclined)

The side can't be perforated by 88mm gun from 600m.

88mm KwK36 Test Results:

Turret:

Front from ±30deg. can't be perforated

Most dangerous angles for the turret- 75 deg (left side) and 285 deg (right side). Was perforated from ~2500m

Left rear side: Can be perforated from 90-135 deg.

Most dangerous was 90 deg (not more than 3500m)

Right rear: can be perforated from 225-270 deg. from distance not more than 2500m

Rear: Can be perforated from angles 150-210 deg.

Most dangerous is 180 deg. (1,400m).

Hull:

Front: Most dangerous 0 deg. (from 600m)

Inclined front sheet-can't be perforated.

Lower front sheet- not more than 1,400m. Most dangerous - 0 deg.

Upper bevels: 45deg., 315deg. 1,400m

Frontal bevels of middle part - -90deg, 270deg. 400m

Border - 90 deg 3500m

Frontal bevel of underturret's box - 75deg, 285deg. 2600m

Border of underturret's box - 90deg. 2400m

Maximal probability of hit for all anti-tank guns to all types of tanks was estimated to be at 800m.

3c. IS-3 (1945-46)

WERE NOT USED in WW2

• Weapon: 122mm gun (D-25) +1-7,62 MG+1-12,7mm anti-aircraft MG
• Armor: front-120mm, border-90mm, rear-60mm, turret-220mm (in other sources 250mm)
• Speed: 40km/h
• Range:95-185km
• Produced: 1,170 units.

Comments to all IS:"IS" is an abbreviation of "Iosif Stalin"

Remarks:

Some heavy (KV) and medium (T-34) tanks could have wheel trawls, i.e. were mine-cleaning units.

Also in RKKA a few exotic tanks were used, like Mk-V and Mk-B received from the armies of the former Baltic countries (tanks of WW I period) Some of them, for example, were used in defense of Riga in June,41 as pillboxes. Also some Vickers tank were used in Baltic region. Captured Finnish Vickers-6tons tanks were used in the defense of Leningrad in 1941. Experimental tanks A-20 and T-29 were used in the Moscow battle. I have information that 4 flame thrower tanks KV-6 were in 124th tank brigade in 1941. The armies of the former Baltic countries had some FIAT-3000, Renault FT-17 tanks and 6 TKS tanketts. FIAT and Renault tanks seem to be have been left (and lost) in winter quarters. In the Leningrad battle the experimental tank KV-220 was used (and destroyed). Also some other experimental and imported tanks took part in the Leningrad, Moscow and probably Stalingrad battles. Experimental tanks "SMK" (S.M.Kirov), T-100, KV-1, KV-2M40 took part in the Winter War 1939-40.

Also a lot of lend-lease tanks were used by RKKA. The first thereof was seen in November 1941 in the Moscow battle.

Some captured tanks and SP guns were also employed.