The Tsar Tank was an extraordinary - though ultimately failed - feat of Russian combat engineering that attempted to create a capable mobile weapons platform able to cross any terrain before it. The system was born during the fighting of World War 1 (1914-1918) to which, in the East, pitted the Russian Empire against the forces of the German Empire and its allies. The Tsar Tank was not a combat tank in the traditional sense as it relied on a tricycle wheeled configuration that utilized two large main wheels set ahead of a smaller pivoting steering system. The frontal wheels - heavily spoked as if wheels on a bicycle - were joined by a single axle between them with extending arms connecting them to the main vehicle body. Along this main body was held the powerplant, fuel stores, and crew compartments as well as armament and ammunition. The design was attributed to Nikolai Lebedenko and Alexander Mikulin - the vehicle sometimes referred to as the "Lebedenko Tank" - and work spanned from 1914 to 1915.
The combat tank of World War 1 was primarily characterized by the lozenge-shaped designs of the British with armament held in side sponsons while it was the French that introduced a capable turreted-armament tank in their Renault FT-17 Light Tank series. Both initiatives held their value on the battlefields of World War 1 and proved instrumental from 1917 onwards in breaking the stalemate of trench warfare that had come to dominate Europe by the end of 1914. The Tsar Tank was a grand departure from both of these measures as its primary intent was to easily traverse uneven terrain using large-diameter (27 foot) wheels with the rear of the system brought along by a wheel set measuring just 5 feet high. The lead wheels were each powered by a Sunbeam-brand engine of 250 horsepower output. Armament-wise, the Tsar Tank concentrated its cannon across three turres. There was a main traversable turret emplacement at center along the roof with its firing arc largely obstructed by the forward wheels. A cannon was also added to each side sponson mounted outboard of the forward wheels and these also held limited firing arcs. It is assumed that machine guns were also meant to be carried for defense against infantry attacks though it is doubtful that the Tsar Tank would ever be fielded without support from armored cars or accompanying tanks.
The shortcomings of the Tsar Tank were quickly brought to light in testing during 1915. Though the large diameter front wheels proved capable of traversing many terrain types, it was the smaller rear section that did the vehicle in. The peculiar design of the vehicle placed an inordinate amount of weight at the rear unit which ended with the vehicle becoming bogged down in the terrain. The sheer mass of the vehicle, and the ensuing political instability emerging from the Russian revolution, was such that no additional effort was made to recover the vehicle until after the war in 1923. Even then, the Tsar Tank was far from reconstituted for additional testing and simply scrapped for its valuable metal - ending the reign of the Tsar Tank in full.
Due to its distinct shape when viewed from above - this resembling the profile of a bat handing upside down, the Tsar Tank was also known as the "Netopyr", translating to "pipistrellus", the genus name for bat.