Tsar Tank
The Tsar Tank (also known as the Netopyr (Нетопырь, Pipistrellus bat) or Lebedenko Tank) was an unusual Russian armored vehicle developed in 1914–1915. The project was scrapped after initial tests deemed the vehicle to be underpowered and vulnerable to artillery fire.
The tank was different from modern tanks in that it didn't use caterpillar tracks—rather, it used a tricycle design. The two front spoked wheels were nearly 9 metres (27 feet) in diameter; the back one was a smaller (only 2 metres (6 feet) high) double wheel, to ensure manoeuvrability. The upper cannon turret reached nearly 8 metres high. The hull was 12 metres wide with two more cannons in the sponsons. Additional weapons were also planned under the belly.
The vehicle recieved its nickname, because its model, e.g., when carried grabbed by the back wheel resembled a bat hanging asleep.
The huge wheels were intended to cross significant obstacles. However, due to miscalculations of the weight the back wheel was prone to be stuck in soft ground and ditches and the front wheels were sometimes insufficient to pull it out. This led to a fiasco of tests before the high commission on August 1915.