We have got accustomed to considering the tank as an armored caterpillar war machine. The first tank “Mark1” created in 1916 by English designers had a caterpillar propeller. Using the caterpillar solved the intensified contradiction which would have occurred in case of using wheels. Such a war machine would have needed a very large wheel capable of providing a high cross-country capability. However, a wheel of this kind has some disadvantages.

Yet there were attempts to solve the cross-country capability problem by compromising – using increased diameter wheels. The Russian inventor Captain Lebedenko proposed such a wheeled tank in May 1915. The machine weighed 2.5 poods (40 to 44 tons) and was formed as a gun carriage having the running wheel diameter of 9 m and rotation speed of 10 rev/min. With such parameters, the machine was expected to easily cross entrenchments, ditches and a vertical wall, to crush a blindage, etc. The “chariot” ran at 28 m/min, which was equal to 18 km/hr.
A scale model of the machine was manufactured. It had 30 cm nickel-plated wheels and a gramophone spring drive. Captain Lebedenko offered this model to Czar. The toy impressed Czar. As a result, the construction of a full-size machine was financed. During the test conducted in August 1927, the machine made a move, broke a big old birch tree with its front axle and stalled with its rear wheel in soil. Another attempt to make the machine move, made in 1918, was also a failure.

So far, the “Czar-tank” (they wanted to call this machine by analogy with the “Czar gun”) has been the largest war machine that ever was in the world's tank building practice. That solution was undoubtedly the strongest one for that time and those conditions. The design simplicity, high arrangement of cannons and machine guns over a battlefield, good visibility for the crew could have made the wheeled tank a strong enemy under those fighting conditions. To stop the wheeled tank, it was necessary to hit exactly the hub of the running wheel whereas hitting any point of the caterpillar was fatal for a caterpillar tank.
The disadvantages of this design are the difficulty to mask the 9-meter tank on a battlefield, high pressure of the wheels on the ground and impossibility to execute fire in the area shielded by the wheels. In addition, the developers committed some errors the most important of which was wrong distribution of load between the running wheels and the rear wheel. All that made the Lebedenko wheeled tank a curious construction which did not have any influence on the tank construction progress.

Source: “Modelist-Konstruktor”.