"January 7th, 1943
#11
In October and November of 1942 factory #100 designed and tested a planetary turning mechanism designed by Engineer Lieutenant Colonel A.I. Blagonravov.
We attach the report on the first stage of trials held with a KV-1S tank and ask you to approve it.
By now, the total length of trials reached 1085 km, of those 135 km was travelled towing a tank. Once the tank with a planetary mechanism even towed two tanks with a combined weight of 75 tons without issue.
The planetary turning mechanism is a new advancement in domestic tank building.
Trials showed that the planetary turning mechanism has the following advantages over clutches:
- Off-road maneuverability of the tank is improved.
- Average movement speed is increased by 25-30%.
- Off-road performance is improved.
- It is easier to steer (12-15 kg of effort instead of 40-50).
- Conditions in which the engine, gearbox, and main clutch improve.
- The lifespan of the brakes increased.
- Fuel expenditure is reduced.
We consider it necessary to recommend this mechanism for mass production and immediately produce a trial batch for front line trials.
With the exception of adapters to connect it to the gearbox and final drives, the same turning mechanism can be used on either the KV-1S or T-34 tanks. Blueprints for the KV-1S variant with corrections made as a result of the trials are ready.
Chief Engineer at factory #100, Maidelman"
CAMD RF F.38 Op.11355 D.1377 L.56
Printed in Glavnoye Bronetankovoye Upravleniye Lyudi, Sobytiya, Fakty v dokumentakh, 1943-1944 p.35