KV-1 first prototype in Finland with the 91st Tank Battalion of the 20th Heavy Tank Brigade near Suma, 17-19 dec. 1939, alongside two T-100 and one SMK.
KV-1 model 1939 with wielded turret. Central front, summer 1941.
KV-1 model 1940, central front, Autumn 1940. Slogan "For Russia".
KV-1 model 1940 of the Moskow heavy tactical reserve, winter 1941/42. Slogan : "For Stalin".
KV1 model 1941 with a complex "Finnish" camouflage pattern, winter 1941/42. Notice also the new spoked wheels.
KV-1 model 1940e Ekranami (up-armored). Unknown reserve Front unit, summer 1942.
KV-1 model 1941 S Ekranami (up-armored), unknown unit, Leningrad sector, winter 1942.
KV-1B (model 1941), 124th Guard Tank Brigade, part of the 24th Tank Division, operating near leningrad.
KV-1B, Leningrad sector, winter 1941/42. The winter camouflage is another variation with omitted spots to create an alternative pattern.
KV-1 model 1941, late production, 53rd army of the Transcaucasian Front, Anglo-Soviet invasion of Iran, september 1941.
KV-1 model 1941/42 with a partially welded turret and the new ZiS-5 long barrel gun. Unknown unit, Central Front, autumn 1942.
KV-1 model 1942 with the fully cast turret. Unknown unit, Southern Front, summer 1942. Slogan "October Revolution"
KV-1 model 1942 (fully cast turret) "kutuzov" in white washable paint livery, unknown unit, northern front, winter 1942/43.
KV-1 model 1942, Unknown unit, Finnish front, march 1942. Notice the DT 7.9mm Mg AA mount and the faded white paint.
KV-1 model 1942 (late production), Unknown unit, Southern front, spring 1942.
KV-1 model 1942 (late production), Central front, early 1943. Slogan "death for death". The original factory green has been modified due the passing of one winter and burning gasoline from an explosion and other chemicals. Fighting inside factories has been not unusual in many street battles.
KV-1 S (for "Skorostnoy", "fast") model 1942 with spoked wheels, Unknown unit, central front, fall 1942.
KV-1-S model 1942 with the new late roadwheels, lead or commander tank, winter 1942/43.
KV-1 S model 1943, Unknown unit, southern front, summer 1943.
KV-1 S model 1943, Unknown unit, Eastern prussia, winter 1943/44.
KV-1-S, late production, unknown unit, Berlin, may 1945.
KV-85, Unknown unit of the guards, Eastern Prussia, june 1944. This transition model between the KV-1 and IS-I was only produced to 143 machines.
KV-2, model 1940, 3rd regiment of the 2nd tank division, central front, summer 1941. The KV-2 was globally an impressive but unsatisfactory model. Only 400 were built as the production stopped by june 1941.
KV-2, model 1940, unknown unit, winter livery, Leningrad sector, december 1941.
Flame thrower versions :
KV-8 (flame-thrower version), 503rd independent armored bataillon, Volhovsky sector, summer 1942.
Captured KVs :
PzkPfw KV-1 756(r), SS Panzer Regiment of the 2nd SS Panzergrenadier Division "Das Reich", group center, spring 1943. Notice the salmon camouflage over the standard dunkelgrau of captured units.
KV-1 C (Model 1942) or PzKpfw KW I 754(r), 3rd SS Panzer-Grenadier Division "Totenkopf", Kharkov, march 1943.
PanzerKampfwagen KW-1 756(r) mit 75mm KwK L/53, 204th Panzer Regiment, 22th PanzerDivision, Kursk, summer 1943.
KV-2 Model 1940 PzKpfw KW II 754(r), Panzerkompanie (z.b.v.) 66, Malta invasion force, 1941. Notice the Panzer III commander cupola and headlight.
KV-1 (Kliment Voroshilov)
Heavy Tank - Soviet Union (1939).
5219 built until 1943 (all variants).
Heavy Tank and "deep battle" concept in USSR :
The concept of "deep battle" was contained the doctrinal use of the Soviet heavy tank, was first theorized during the late twenties, then refined and eventually adopted by the Red Army Field Regulations in 1936. The tactical deep battle doctrine advocated for fast battle tanks (BT serie and T26), reconnaissance types (T27, T37A, T38 tankettes), and penetration tanks medium or heavy ("Tyazholy"), the latter were also also called "siege tanks" and have to be able to resist most AT gun calibers, either deployed by enemy infantry or other tanks, and to destroy them as well. They were to be placed on key tactical positions to drag and concentrate enemy fire, or destroy enemy fortified position while assisting infantry. Protection was therefore given priority over mobility.
T35, T-100 and SMK :
After the T28
, which was considered a medium, infantry tank design, the T35 became the first of these heavy tanks to enter service in USSR. This was a true monster, influenced by the multi-turreted fad which came from Great Britain, but was quite complicated and unsatisfactory in operations.
A new 1937 specification gave birth to the two T100s, a unique SMK prototype, showing a new arrangement of firepower, with tandem turrets. All three were tested in operations in Finland during the "winter war" (september-december 1939). They proved resistant but shown very poor reliability and mobility. They were also costly, over-complicated, and difficult to maintain. Another prototype however, the KV, has been drawn by the same team which designed the SMK, as a single-turreted variant. During these operations, the two KV prototype simply outperformed the others and was subsequentely approved for a 50-units preserie under the name of KV-1...
Origin of the Kliment Voroshilov Tank :
The TsKB-2 design bureau responsible for the SMK, through chief engineer Zh. Kotin, designed at first an all-wielded hull with cast turret and large parts, with wide, reinforced tracks and a torsion-bar suspension. Alongside the SMK, the KV, named after People's Defence Commissioner and political stateman Kliment Voroshilov, was essentially a single-turret variant, the extra weight saved beeing replaced in extra frontal and side protection, without any sacrifice to mobility. Initially not meant for production, the KV was given direct approval from Stalin himself. Thus, this model should have been named "Kotin-Stalin" (KS-1) instead. A wooden mockup was ready in April 1939, and first presentation to the general staff in september. Both prototypes were tested at tested at the Kubinka proving grounds near Moskow, and immediately after in real combat conditions in Finland. The two KVs prototypes and the first 50 preserie KV-1 were virtually identical, only differing by some redesigned parts for easier production. The hull, transmission, optics, and torsion bar suspension were all borrowed to the SMK. First production was assumed by Kirov Factory, ChTZ, and the first 50, were part of the "model 1939", but the first were delivered in march 1940.
Design of the KV-1 :
The model 1939 was nearing 45 tons in weight, with a long hull (6.75m) relatively narrow if not for the very large tracks. The generous mudguards above gave exceptional room for storage. However, as no transmission was able to cope with such mass, the designers found an expedient, giving both prototypes and the SMK, an old but sturdy Caterpillar system, which proved tricky, even unreliable in operations. The driver sat in the middle, and the radio operator/machine gunner sat on the left, the three other crewmembers beeing centered in and below the turret. This had poor visibility, with narrow vision slits. The driver had a his frontal slit made of poor quality laminated glass, which proved blurred most of the time, and his vision periscope has limited traverse. The commander (which also the loader) had two turret periscopes. The wheel train comprised front idler wheels and rear drive sprockets (T28 model), and a set of 6 twin roadwheel bogies, each sprung to an independent torsion-bar apparatus. There were also, due to the weight of the tracks, three large and thick return rollers. These large tracks had excellent traction on soft ground (snow and mud), and overall, the protection, at 90mm on the front (glacis and turret) was unrivalled for the time, if not for rare equivalents like the British tanks Matilda II (80mm) and the French B1 bis (70mm), but way ahead any german tank.
The KV-1 model 1939 and 1940.
At first, the 76.2 mm F-32 was chosen as main armament, but due to delays in production, the first 50 preserie models and all remaining model 1939 were equipped with an initial medium-velocity "short" barrel L-11 of the same caliber, fitted with a recoignisable recuperator aborve the barrel. The F32 was able to fire AP (F-342 rounds) and HE shells. The BR-3502 AP rounds were capable of a 612 m/sec. giving a 66mm armour-piercing capacity at 500m. Secondary armament comprised a coaxial DT 7.9 machine gun, another in a rear turret ballmount, another mounted in a hull ballmount, and an extra AA mount later on the model 1942. The engine was the 12-cylinder diesel model V-1, 600 hp@2000 Rpm (450 kW), and then V2 (model 1940), fed with a 615 liters capacity storage. In all, 141 Model 1939 were delivered, followed by 243 to 250 of the model 1940. Most were delivered during 1940 and early 1941. The model 1940 (also called KV-1A) was equipped with the longer F32 gun, and a new mantlet. When the production began, the german invasion was on its way. The Kirov factory was later moved at Chelyabinsk during the winter 1941, and a new model was designed.
The KV-1E or Ekranami
Before the model 1941 production was started over after the factory was delocalized in the Ural, many KV-1s were taken in hand for an expedient armour improvement. These versions called "Ekranami" ("with screens"), received tailored 20mm soft steel plates, bolted-on (with huge bolts), as appliqué to the turret, frontal glacis and sides of the hull. These KV1-E were mosty surviving units of the earlier model 1939, which were up-gunned with the F32 in the same process, and later 1940 and 1941 models, sometimes former damaged and recovered tanks. Exact number of this variant remains mysterious. Some sources speaks of 150 to 200+ units beeing converted in 1942. This was a response to new German tactics, hastily devised on the spot to counter the impregnable KV-1. The introduction of the new PaK-38 and Pak-40 AT guns and later some airborne weapons like the MK 101 fielded by the Henschel 129 ground attack aircraft urged this conversion. Total armour thickness, additioned, was around 110-120mm, making once again the KV-1 a nearly immune vehicle.
The KV-1B model 1941:
The model 1941 was designed and produced at Chelyabinsk. A model F-34 gun was fitted. This was the same gun installed in most T-34/76. As a response to the field-expedient appliqué armour, the hull, sides and turret were protected by an additional 25 to 35mm extra thickness, and the turret was now cast instead of wielded. This version also introduced many simplifications for mass-production. However, it was slow to arrive at the front, and the first model 1941 came out operational in early to mid-1942 at best. The late production received even a longer barrel gun, the ZiS-5 76.2 mm. This increased somewhat its penetrating performances. However by the fall of 1942, new German tanks like the Panzer-IV F2 and 50mm armed late Panzer III, outranged the KV-1 while still not able to pierce it. This version however still retained the original V12 diesel, and was decidedly underpowered. Speed was reduced further and this proved an issue in combined operations with the T34. Production of this model was around 1200 units, according to the factory log.
The KV-1C (model 1942):
The model 1942 was essentially a late up-armored model (10-15mm), either with a cast or wielded turret. This was also the biggest production of the type, with around 1700 units. They were also all armed with the 76.2 mm ZiS-5 and sometimes equipped with AA mounts. However criticism about the serie prompted parallel studies to improve the KV-1 as a whole. These reports stated that its only asset was an excellent protection, however, speed and agility were poor, the transmission proved too often prone to broke down, the suspensions, crumbling under the raising weight also shown critical stress failures, as well as the engine (The V12 V-2K, a modified version of the T-34 diesel), overwhelmed. Final weight of this 1942 version was around 48 tons. Only the German Tiger was equivalent in same terms, but the latter was equipped with quite better optics and a gun which far outclassed anything in the field. This led to the two last improved versions of the type, before the production really stopped for better designs.
The KV-1S : The fast one.
The main criticism about the weight imposed a completely revised version with somewhat "downgraded armor" in order to regain some agility. In fact, this was not an equal sacrifice. Some vital parts, determined after carefuly studied statistics about tank loss reports, were still well protected, while sacrificing others. This was a near "all-or-nothing" protection, which also came with special tactical manoeuvers instructions in order to reduce the exposure of these "weak spots" to the enemy. However the engine was untouched. Another improvement concerned the cast turret, which was redesigned completely, lower, smaller, with slightly sloped sides, and most importantly for the first time, fitted with a real commander cupola bearing all-around vision blocks, which in turn greatly improved the overall vision and efficience of the commander. However, this KV-1S (for "Skorostnoy" - "fast"), was still much cheaper than the T34/76, for the relative same performances. By late 1943 they were concerns about the cancellation of this new version, which occured after 1370 has been delivered, from autumn 1942 to the fall of 1943. Total weight was 42 tons, and protection ranged from 30 to 75mm. The main armament, a 76.2 mm L42 was fed by 114 rounds, and the three DT machine-guns by 3000 rounds.
The KV-85 : Blueprint for the IS-I.
Another strong criticism about the KV-1 concerned its main armament, which was the same as the average, mainstream tank of the read army, the T34, while beeing costier and with far less mobility. A better gun could have effectively saved the KV-1, making something comparable to the last version of the panzer IV or the Tiger. By 1943, Lieutenant-Colonel Kotin technical bureau was split in two, a part beeing affected to studying a new stopgap heavy tank based on the KV-1, waiting for its replacement to come. The team choosed naturally the improved KV-1S but increased the armor protection in vital parts to 110mm(4ft 3in), and widened slightly the hull to accomodate a larger turret, and gun, the 85 mm D-5T which was also choosed to equip the IS-85 (forerunner of the famous IS-I). Due to this interim position, the KV-85 was only produced in limited quantity by the beginning of 1943. 143 units of this ultimate version will be delivered until the production stopped for good. The KV-85 had the same engine as its predecessors, and was 46 tons strong, with a 60mm (hull) 75 (frontal glacis), to 100-110mm (turret front, sides and rear). Max speed was around 40 kph and range, 250km. The DT-5 gun (SU-85), was a shorter derivative of the original 85mm AA gun (792 m/s (2,598 ft/s) muzzle velocity).
KV-1 tank gallery :
The KV-1 in action (1941-44).
As the production began in 1940, at a slow pace, only a handful of KV-1s were operational when Operation Barbarossa began. Usual figures are about 530 operational into twenty-nine mechanized corps, alongside all available T34s (1590 tanks in all). They were about a third KV1s for each of these units. They first met the Wehrmacht on june, 23, 1941, the second day of the invasion. More precisely , it was at the Battle of Raseiniai, when Soviet 2nd Tank Division from the 3rd Mechanized Corps clashed with 6th Panzer Division near Skaudvilė. They encountered little resistance from forces composed mainly of PaK-36 and 38 AT guns and Pz35(t) light tanks. The next day, a single KV-1 succesfully blocked any advance of some elements of the 6th Panzer Division during 24 hours, before running out of ammunition and retiring. It has been hit by dozens of different calibers, but remains unscaved. At Krasnogvardeysk (Gatchina, near Leningrad) on August 14, 1941, a small unit of 5 well-hidden and entrenched KV-1s, plus two in reserve, with twice the usual ammunitions, including a majority of AP shells, were skillfully placed around the single road bordering a swamp. This unit commanded by Lieutenant Zinoviy Kolobanov, destroyed some 43 German tanks from German 8th PzD during a single half-hour action. Kolobanov was later awarded the Order of Lenin and made Hero of the USSR.
The KV-2, heavy howitzer version. This was a generally unsucessful variant. The turret was easy to spot, top-heavy, making the tank fairly unstable. Plus, the howitzer blast provoked excessive vibrations for the engine and transmission.
Many alarming reports later all fired in the same direction : These "new" Russian tanks were nearly unstoppable. In fact their ignorance has been one of the biggest blunder of German intelligence prior to the invasion.
Facing these, the Germans had a total of 3266 tanks, but only 1146 Panzer III-IV armed with 50mm or 75mm barely able to penetrate the armor (and only on weak spots) of the two models (T34 and KV-1). Most of the KV-1s were concentrated in 6th, 4th, 8th, and 15th Mechanized Corps during the summer, and all but one were send in Ukraine. They suffered heavy losses however, despite beeing usually bypassed by the Panzers, left to the air support, field artillery and 88mm, or special antitank squads using shaped charge grenades. Many also broke down, run low on fuel and layed abandoned due to the confusion of the first two weeks of Barbarossa. The total losses were far superior anyway to those related by the German reports, and by the autumn 1941, few were still extant. Anyway, the impression left by the KV-1 (as well as the T34, which was faster and more numerous), from the simple soldiers to the general staff, was huge. It triggered an unpecedented Panzerkommision on 20 November 1941, which studied remains of both tanks on the field. The T34 is notable to have inspired the development of the sloped-armoured Panther and the KV-1, with its straight armor, the Tiger.
After a ruthless relocation in dire conditions of the entire Russian war industry next to the Ural mountains, production of the KV-1 was resumed, and two models were produced alongside, the "cast turret" and "wielded turret", which otherwise, were generally similar, bearing the same L32 gun, and for easier production the model 1942 was a near-repeat of the former although up-armoured. Older models were massed together for the counter-offensive of Moskow in january 1942, but the germans were now better prepared, although still fielding the same Panzer III-IV. Among these, many were upgraded as S Ekranami "with screens", receiving thick appliqué bolted plates. This was a response to some new german weapons, like the shaped charges and airborne AT guns. Throughout 1942, the KV1s performed well, although combined operations with the T34 was problematic due the the speed difference between them. Too often the KV-1s were relegated as a support rearguard, and committed only when encountering a fierce resistance.
These tanks fought at nearly all major engagements of 1942-43, including the large counter-offensive of Stalingrad, in january 1943. By then, Soviet industry has produced enough T34 to litterally overwhelm the KV-1 in number (the latter beeing much costier). Growing discontent about the type revolved usually around the same issues : Too slow (easier to spot and target), prone to transmission failures, simply too heavy for many bridges and at the same time, non equipped to ford deep rivers, and lacking range against the late 1942 german AT units and rearmed Panzer IVs. Late versions, even heavier, lost what left of its former manoeuverability, while at the same time beeing still not better armed than the T34. Further heavy losses at Kursk proved they definitely found their match in the new German tanks generation. Beeing not upgunned was found acceptable for the general staff however, which condidered them as breakthrough tanks, operating against infantry and fortified lines of defenses, firing HE shells at relatively short range and only carried a few AP rounds for occasional encounters... They kept this tactical specialization until late 1943, before beeing superseded by the JS-II. By 1944, the existing KV-1s were mostly of the late KV-85 type. Their heavy armor proved still effective while dealing with well-prepared german defences. However, by the end of 1944 they were seen as obsolete. There is even no evidence that any KV-1 or KV-85 took part in the battle of Berlin.
Derivatives of the KV-1 :
The KV-2 Heavy Artillery Tank: The howitzer version.
When encountering difficulties on the heavily fortified mannehreim during the winter war in Finland, the general staff demanded a specially equipped version fitted with a heavy howitzer, intended to deal with concrete bunkers, in support of the regular KV-1 units. But instead of choosing a more pragmatic solution of a traditional SPG, the soviet engineers tried to get the best of both world in a hurry, while using the same turret ring to accomodate an fully traverse, redesigned turret to house the gargantuan howitzer. This gave the KV-2 an unmistakable profile, with its huge, towering turret, which was only accessible by a ladder. An obvious target which was also a topweight compromising the lateral stability of the tank while crossing a sloped terrain. All these deficiencies were taken in account when the factory were relocated in the new "Tankograd" complex at the steps of the Ural. The production was no longer maintained. Only 334 were built in all from late 1939 to mid-1941.
The KV-8 Flame-thrower:
The KV-1 was also chosen to be used as plateform for the new ATO-41 flame-thrower. The gun mantlet accomodated in fact, the flamethrower tube, a coaxial DT machine-gun, and, replacing the former ZiS-5 gun, a 45mm QF model 1932 in disguise, housed inside a 76mm tube. The 45mm was standard issue in the BT serie and the T26, and had good penetration power against 20-25mm of armor. 45 units were converted using KV-1B hulls (model 1941), and later on, 25 more based on the upgraded KV-1S. Two prototypes of the next version (KV-1M), and a few experimental KV-6 (the flame-thrower was relocated in the hull) were also built and tested in combat.
The SU-152 SPG.
Probably the most distinctive soviet SPG of the war, the SU-152 renewed the idea formerly tried, although unsuccesfully by the KV-2. Developed relatively late in the war, for the upcoming Operation Uranus (the great Stalingrad counter-offensive), this "pillbox killer" was a more sounded (and simpler) design, where the long howitzer was simply relocated into the hull, making it easier to manufacture, more stable and more difficult to hit. It was based on the KV-1S and arrived in time for Kursk, proving also an excellent improvised anti-tank machine, soon nicknamed "the beast killer". It was later on, associated to th great offensives of 1944-45, and was widely used (and photographed) during the battle of Berlin. Around 700 were built in all, including the late ISU-152 based on the improved IS-I serie chassis.
Heavy tanks :
The T-150, KV-220 and KV-222 were early 1942 projects with downgraded armor, traded for speed, and 700 to 850hp diesels, armed with 76mm to 85mm. The KV-11, 12, and 13 all remained paper projects. They were respectively a 85mm variant, a chemical tank and a new generation "universal" medium tank drawned by late 1942.
Super-heavy tanks :
The KV-1 chassis served as a basis for many tests, starting with the KV-3, a single prototype, which had an extra pair of rollers, a lenghtened hull to accomodate a New 850 hp V-2SN engine, a hull protected (at the front) by 130mm of armor, and a 107mm ZiS-6 gun. It was destroyed in combat by German field artillery in 1941. The KV-4 and KV-5 were derivative of the former, but stayed as a paper project. These super-heavy tanks would have been up to 150 tons. 20 different projects were proposed but all cancelled by 1943 in favor of the IS-1.
The experimental KV-7 was a self propelled-gun with three guns (one 76 and two 45mm), and later, the KV-9, a battle-tested 122mm SPG prototype, wich was an early forerunner for the SU-122 serie. In the same scope, the KV-14, carrying the 152mm in a more conventional way, was also the forerunner for the SU-152 serie, as well as the unique U-18 and U-19, which existed only as a mockup or on paper. The KV-10 (or KV-1K) was fitted with four 132mm M-13 rockets launchers installed on the large mud-guards but remained a prototype.
KV-85 variants :
Only 148 of this promising intermediate model were built, before the IS-1 was introduced. It led anyway to four variants. The KV-85G was a competitor, also armed with a 85mm S-31 cannon, but the KV-85 was choosed instead. The KV-152, 100 and 122, were all prototypes derivatives armed with a short 152mm (for support), a long 100mm and a 122mm built and tested in 1943-44. They served as testbeds for the IS-II.
Legacy of the Kliment Voroshilov Heavy Tank:
Despite beeing plagued by problems due to a rushed conception, the formidable reputation of the KV-1 came first from a legendary sturdiness, which was paid in return by a record weight. It paved the way for the next generation of Soviet Heavy tanks which took everything from it. Despite the name, their new turret and heavier guns, the IS (Iosif Stalin) serie were still KV-1s in disguise. They borrowed everything from the chassis to the tracks, road wheels, suspensions, diesel engine, transmission, and most of the equipment. And if the IS-III (which was never to fire a shot before the capitulation) has a different look, with a brand new, entirely redesigned sloped hull and characteristic rounded, flat turret of the Soviet postwar design, it remained essentially a KV-1 inside. The KV-13 design tried briefly to reunite the T34 and the KV-1 in a single package, but failed. However its legacy was to endure in the and very last Soviet heavy tank design, the T10 (1958), after a long serie from the IS-5 to the IS-8. They were to bring support to the more agile T54/55 during the cold war. But the type has to definitely fade in time, in favor of the "universal" type, the main battle tank.
KV-1B Specs. (model 1941)
||5,80 x 4,20 x 2,32m
|Total weight, battle ready:
||4 (commander, driver, 2 gunners)
||V12 diesel V2 600 bhp (400Kw)
|Max Speed :
||38 kph (26 Mph)
|Range (road/off road):
||200 km (140 mi)
||1x75mm L32 + 3x DT 7,62mm mg.
||30 to 100 mm
KV-1 Links and references :
The KV-1 on wikipedia...
The KV-1 on wwIIvehicles.com