"March 21st, 1937
#4250ss
To the chief of the ABTU, Divisional Commander Bokis
CC:
Chief of Armament of the Red Army, Army Commander 2nd Class, comrade Khalepskiy
Chief of the General Staff, Marshal of the Soviet Union, comrade Yegorov
Experience in using the T-26 tank demonstrated its poor suitability for fighting in cities, where the tanks took heavy losses. There is no reason to assume that other types of tanks will perform any better. We much have tanks that are especially designed for successful street fighting, not only in small settlements, but in large cities, where the enemy will have the ability to attack our tanks from above.
Discuss this issue (invite Arman and Krivoshein) with specialists: engineers and designers. Report to me in 20 days regarding your ideas for a tank that is designed for street battles.
Consider the following:
- The tank should, in my opinion, possess considerable penetration. It should be able to destroy not only barricades of all types, but also stone obstacles: walls, houses, etc, which means that the front part of the tank should be reinforced and shaped like a battering ram. Think this idea over.
- It must be possible to fire machineguns, or, more desirably, cannons up at an angle of 60-70 degrees to hit the enemy on top floors of houses. This requires good visibility upwards and to the sides.
- The tank crew must be protected from incendiary fluid.
- Speed can be sacrificed for improved armour, especially in the front, but not agility.
- The rear of the tank must be covered by fire.
- It is desirable to have a BT-IS-like Tsyganov convertible drive.
- It is desirable to protect the tracks from hand grenade bundles.
These are the requirements, in very general terms, for a tank designed for street (city) fighting. Report your ideas on the topic and on timelines for designing an experimental prototype, if you consider this tank necessary at all.
K. Voroshilov."