The Soviet “railroad torpedo” ЖДТ-3 (ZhDT-3) was developed by the Ordzhonikidze Machine Plant of Podolsk in 1935 as a weapon against enemy armored trains.
It consisted of a small, two-axle, battery-powered trolley armed with a 495lb (225 kg) bomb containing a 220lb (100 kg) high-explosive charge. The ZhDT-3 had a top speed of 37 mph (60 km/h) and a range of about 6 miles (10 km). Production started in 1938 and it was planned to equip each armored train with five of these devices. While many of these were in service in 1941 at the outset of the war, there is no record of their actual use in combat.
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