 BT tanks along with T-26 constituted the basis of the tank arm of Soviet Armies.As the technical lead of the project together with M. I. Koshkin and N. A. Kucherenko headed development of the medium T-34 tank in 1940.During the Great Patriotic War, he was the chief designer of upgrades of the T-34 tank, which was recognized as the best tank of the period of the Second World War.