BT-SV

The BT-SV ( Bystrohodny Tank-Stalin Voroshilov) was an experimental Soviet light tank. In 1936, Soviet engineer Nikolai Tsyganov proposed a new high-speed light tank based on the BT-5. The design was to incorporate sloped armor similar to the T-34, which was also being developed at the time, and a transmission identical to that of the BT-5. The armor was angled at around 15°–58°. It could protect the tank from 45mm rounds. Only two prototypes were built, both of which saw field testing. The vehicle never saw mass production, due to the lead engineer Nikolai Fedorovich Tsyganov being arrested alongside many of the other engineers of the project during the Great Purge. The tank also shows concern on the reliability of the suspension and transmission, as the extra weight added a lot of stress on the mechanics.