Extensive Soviet experimentation with combat tanks began during the middle of the 1920s and continued well into the Cold War period (1947-1991). Various attempts at perfecting a locally-created combat platform were made and this resulted in mixed successes through several notable and other, less-worthy, designs. One of the chief contributions by Soviet engineers heading into the 1930s became the "T-26" Light Infantry Tank which saw production surpass 10,000 vehicles before its end was met (this tank is detailed elsewhere on this site). The series fought throughout the pre-World War 2 period and into World War 2 (1939-1945) proper where its last actions were ultimately recorded.
To improve upon the inherent performance of this successful tank, Soviet engineers attempted to fit the American "Christie" suspension system to the existing T-26 and this work went on to produce the ultimately-abandoned "T-46". The original leaf-sprung, bogie-style wheel arrangement was done away with and, in its place, a more traditional (and rather modern) track-and-wheel arrangement was fitted that involved four road wheels to a hull side, a drive sprocket at front, and a track idler at rear. Two track return rollers were fitted to aid the track-link sections about the upper reaches of the hull sides. A unique quality of this design was also the tank's ability to have its track-link lengths removed and run on its road wheels like an automobile (as was the case with the Soviet "BT" Fast Tank series detailed elsewhere on this site). For this mode of travel, the front pair of wheels were steerable by the driver with drive power being delivered to the aft-pairing.
Design work on the new vehicle took place in 1933 and construction of the pilot vehicle was handled at eh Kirov Works, Factory No.185 of Leningrad. As the original pilot form proved underpowered, a second prototype followed in November of 1935 as the "T-46-1".
As completed, the 10.3 tonne vehicle sported a length of 5.5 meters with a width of 2.3 meters and a height of 2.3 meters. Its operating crew was three men and armament was contained in a traversing turret fitted over the hull (the same as found in the T-26 Light Tank). Primary armament consisted of 1 x 45mm 20K L/46 main gun backed by 1 x 7.62mm DT machine gun in a coaxial mounting. A second 7.62mm DT machine gun was managed through a mounting at the rear turret face giving the crew all-round protection. A flamethrower could also be carried that provided up to twelve bursts of ranged fire out to 20 meters. Armor reached 15mm at the thickest facings for basic protection against small arms fire.
Drive power was from a GAZ MT5-I 12-cylinder Otto gasoline-fueled engine developing 330 horsepower. This provided the vehicle with a road range out to 500 kilometers but, more importantly, a road speed nearing 55 kmh on tracks and 72 kmh on its road wheels.
The T-46 had an initially good showing in 1936 to the point that the Soviet Army commissioned for fifty vehicles to be built to the pre-series standard. However, production was quickly abandoned after just a handful of examples were completed for the design showed itself to be just as expensive as the more valuable T-28 Medium Tank series (detailed elsewhere on this site). The T-46 lacked armor protection and firepower while also costing as much as its medium-weight counterpart which led to the T-46's demise and abandonment. The few examples that were finished were used in the fighting of the "Winter War" with neighboring Finland during 1939-1940 and then pressed into the desperate situation of June 1941 when the Germans invaded the Soviet Union through "Operation Barbarossa". The small stock of T-46 tanks was out of service from then on.