Teletank
Teletanks were a series of wireless remotely controlled unmanned tanks produced in the Soviet Union in the 1930s and early 1940s so as to reduce combat risk to soldiers. They saw their first combat use in the Winter War, at the start of World War II. A teletank is controlled by radio from a control tank at a distance of , the two constituting a telemechanical group. Teletanks were used by the Soviet Red Army in the Winter War against Finland, fielding at least two teletank battalions at the beginning of the Eastern Front campaign in the Second World War. Design Teletanks were equipped with DT machine guns, flamethrowers, smoke canisters, and sometimes a special 200–700 kg time bomb in an armoured box, dropped by the tank near the enemy's fortifications and used to destroy bunkers up to four levels below ground. Teletanks were also designed to be capable of using chemical weapons, although they were not used in combat. Each teletank, depending on model, was able to recognize sixteen to twenty-four different commands sent via radio on two possible frequencies to avoid interference and jamming. Teletanks were built based on T-18, T-26, T-38, BT-5 and BT-7 light tanks. Standard