Note new combat weight saving track style and modern horn but old-style periscopes
KV-1s Heavy Tank
First production series with combat weight saving road wheels, early fall of 1942
KV-1s "skorostniy" Heavy Tank
Though successfully fighting the German advance in the first year of the Russian-German war, the heavy and clumsy KV tank was about to loose his armour advantage against the upcoming German armament in summer 1942.
A new improved KV had to be designed, lighter and thus faster in combat, the KV-1s (s=skorostniy=fast).
The reduction in weight was to be achieved by reducing the armour strength and ammunition storage by fielding a revised cast turret.

Trials with the new engine V-2K with 650hp already began in March 1942 in accordance with the design of a completely reworked transmission.
In July/August 1942 two KV-1S preseries vehicles were tested.
These had a combat weight of 42.3 tonnes and a top speed on the road of astonishing 43.3 km/h (the KV-1 barely reached the factory requirement of 35 km/h. 15-20 km/h was more realistic).
The KV-1s was still armed with the 76.2mm ZIS-5 gun albeit of improved design with parameters now equalling the F-34.
In July altogether 52 KV-1S had been manufactured.
In late August 1942, the first series-production KV-1S reached the Red Army.
In September 1942, the mass-production for the KV-IS was launched and followed by instructions to again increase the ammunition complement from 90 to 114, which increased weight to 43.4 tonnes.
A total of 180 KV-IS was built in that month, the highest-ever monthly output of this model.

Aside from the already mentioned principal changes in design, the KV-1S was also the first KV series tank that received the long-desired commander's cupola.
The hull of the KV-1S can be identified by the angled engine deck - introduced to safe weight.
The introduction of the new transmission finally led to a significantly enhanced reliability of the whole drivetrain and powertrain.
The shape of the new cast turret was now ballistically even better than the late KV-1 types.
The turret now also mounted two hatches to enter or leave the vehicle for the three-man turret crew.
Furthermore planned improvements, such as an even better commander's cupola could not be introduced until the KV-1S production came to an end in August l943 after some 1,300 tanks had been accomplished.
Note factory number on rear turret, rounded engine deck rear and displaced spare fuel tanks
Fading wintherwhite camouflage in spring of 1943
Moscow's farmer handing over KV-1s tanks donated to the army
Fading wintherwhite camouflage in spring of 1943
Late production series of 1943
Handrails on body front, body rear and turret sides as well as new road wheels
A column of KV-1S tanks of the 6th Guardian Armored Breakthrough Regiment on the march to the combat area, spring of 1943
Note funny "palm shape" of radio antenna
Destroyed or Disabled
Disabled late production model, probably of the 1st Guards Tank Breakthrough Regiment of the 28th Army, Southern Front 1943


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Last Updated: January 19, 2014