On June 21st, 1941, trials of the M1940 tank, created by the talented American engineer Walther Christie, concluded in Voronezh.
The USSR bought two tanks of this type, with technical documentation and a production license. Christie's vehicles had exceptional mobility characteristics, and could move not only on tracks, but on wheels.
The trials showed that the M1940 tank could be accepted into service with the Red Army, provided changes were made to the design to improve the reliability and adapt it for capabilities of Soviet production.
The Christie tank became the ancestor of the Soviet BT tank family. These convertible drive vehicles composed a significant percentage of the Soviet tank park and fought at Khalkin-Gol, in Western Ukraine, Belarus, Finland, and in the initial stages of the Great Patriotic War.
Read more about the BT-2, the first in the fast tank family, here.
Original article available here.