After experience in the Russio-Finnish War with the T-100 and the SMK, it was found that they were too large and complex.1 Design work for the new heavy tank started in 1938.9 Kotin showed design plans for a single turreted heavy tank to Stalin in August 1939 and it was approved to construct a KV prototype.1
This vehicle was originally called the Kotin-Stalin but was officially changed to the Klimenti Voroshilov5,8 / Klementi Vorishilov / Marshal Klimenti Voroshilov4,7/ Kliment Voroshilov3 (KV) after the Defense Commissar.
The KV-1 borrowed the hull, transmission, optics, and torsion bar suspension from the SMK.1
Initially the armor was welded.5
The KV-1s were used as assault or break through tanks.8,9
The driver sat in the middle.5,7 The radio operator / machine gunner sat on the left.5,7
The KV-1's vision was very limited for the commander and driver.1 The driver had a limited traverse periscope and a slit in the front that had laminated glass, but it was usually of poor quality and hard to see through.1 The commander of the KV-1 had two periscopes mounted in the top of the turret.1 He was also the gun loader.1
The engine was the same as the T-34 but with minor modifications.
Drive sprocket was at the rear.7
Initially the KV-1 was to have the 76.2 mm F-32, but due to delays the 76.2 mm L-11 was initially used.1
| Type | Name | Weight | Muzzle Velocity | Penetration |
|---|---|---|---|---|
| 500 m | ||||
| AT2 | BR-3502 | 6.3 kg2 | 612 m/sec2 | 66 mm2 |
| HE2 | F-342 | 6.23 kg2 | 610 - 635 m/sec2 |
N. L. Duchov was the responsible designer from the S. J. Kotin design bureau that started development of the KV-1 in February 1939.2
The prototype was built at the Kirov Factory in February 1939.3,5 A wooden mockup was ready in April 1939.5 By September 1939 the first prototype was show to the General Staff.2,3,5 It was accepted in December 1939 / December 19, 19392,3, with production starting in February 1940.5
The KV-1 prototype was tested at the Kubinka test grounds outside of Moscow alongside the SMK and T-100.1
They came from the production lines in Leningrad and went straight to the front at Karelian.2 The factory was later moved to Chelyabinsk.2
In February 1940, 22 / a platoon of KV-1s were sent to Finland4 for trials.9
The T-100, SMK, and KV-1 prototypes were apart of the 91st Tank Battalion of the 20th Heavy Tank Brigade and had their first combat near Summa from December 17 to 19.1
Despite hits from Finnish antitank weapons none were knocked out.3 It was also found that the diesel engine proved to be very reliable.3 The wide tracks allowed it to have excellent cross country performance.3
By June 1941 there were 636 produced. By the Battle for Moscow (December 1941) 1,364.
| KV-1 | |
|---|---|
| Crew | Commander, gunner, auxiliary driver, driver/mechanic, radio-operator Commander/loader, gunner, 2nd driver/mechanic, driver/mechanic, hull gunner/radio operator7 51,3,4,5,6,7,9 |
| Physical Characteristics | |
| Weight | 94,600 lb9, 104,791 lb5 42,910 kg1, 43,000 kg4,9, 47,500 kg5 42.23 tons1, 42.3 tons4, 43 tons1, 43.5 tons7, 46.35 tons3,6 |
| Length | 20.6'5, 21' 11"4,9, 22.6'3,6, 24' 3"1 6.3 m5, 6.68 m4,9, 7.41 m1 |
| Height | 7.9'5, 8' 8"'3,6, 8' 10.7"9, 8' 11"4, 9' 5"1 2.4 m5, 2.71 m4,9, 2.87 m1 |
| Width | 10.2'5, 10.65'3,6, 10' 10.7"9, 10' 11"4, 11' 5"1, 3.1 m5, 3.32 m4,9, 3.49 m1 |
| Width over tracks | |
| Ground clearance | |
| Ground contact length | 14.2'3 |
| Ground pressure | 10.68 psi, 10.7 psi5, 11.23 psi 0.7 kg/cm2 5 |
| Turret ring diameter | |
| Armament | |
| Main | 76.2 mm M1938/39 L/30.53 |
| Secondary | |
| MG | 3: MG3,6 4: 7.62 mm MG9 up to 4: 7.62 mm MG4 |
| MG - coaxial | 1: MG7 1: 7.62 mm DT MG1,2,5 |
| MG - rear | 1: MG7 1: 7.62 mm DT MG1,2 (some models)5 |
| MG - hull | 1: MG7 1: 7.62 mm DT MG1,2,3 |
| Side arms | |
| Quantity | |
| Main | 1113,5 |
| Secondary | |
| MG | 3,0005, 3,0243 |
| Side arms | |
| Armor Thickness (mm) | 30 - 706, 754, 75+256, 75 - 1005, 90-1107, 1009 Front: 2.95"1 Front: 751 |
| Hull Front, Upper | 755, later models: 75+355, 1063 |
| Hull Front, Lower | |
| Hull Sides, Upper | 75 - 773 |
| Hull Sides, Lower | |
| Hull Rear | |
| Hull Top | 30 - 403 |
| Hull Bottom | 30 - 403 |
| Turret Front | 3.5"1 30 - 1003, 901 |
| Turret Sides | |
| Turret Rear | |
| Turret Top | |
| Engine (Make / Model) | W-2-K2, V-27, V-2-K IS5, V2K4,9, V-2K1,3 |
| Bore / stroke | |
| Cooling | Water5 |
| Cylinders | V-121,4,9, 123,5 |
| Capacity | |
| Net HP | 5001, 5503,4,6, 6007,9, 600@2,000 rpm5 |
| Power to weight ratio | 12.6 hp/ton5 |
| Compression ratio | |
| Transmission (Type) | |
| Steering | |
| Steering ratio | |
| Starter | |
| Electrical system | |
| Ignition | |
| Fuel (Type) | Diesel1,3,4,5,6,9 |
| Octane | |
| Quantity | |
| Road consumption | |
| Cross country consumption | |
| Performance | |
| Traverse | 360° |
| Speed - Road | 21.7 mph4, 21.75 mph9, 21.8 mph1, 22 mph3,6,7 35 kph1,4,9 |
| Speed - Cross Country | 8.1 mph1, 12.4 mph 13 kph1 |
| Range - Road | 93 miles4, 93.2 miles9, 99 miles1, 140 miles1,3, 210 miles7 150 km4,9, 160 km1, 225 km1 |
| Range - Cross Country | 62 miles1, 94 miles3 100 km1 |
| Turning radius | |
| Elevation limits | |
| Fording depth | |
| Trench crossing | 8' 6"9 2.59 m9 |
| Vertical obstacle | 3' 8"9 1.2 m9 |
| Climbing ability | |
| Suspension (Type) | Torsion bar1,3 |
| Wheels each side | 6 twin steel7, 121 |
| Return rollers each side | 37 |
| Tracks (Type) | |
| Length | |
| Width | 2' 3.5"3,7 |
| Diameter | |
| Number of links | |
| Pitch | |
| Tire tread | |
| Track centers/tread |
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