In 1915 the Russians decided to build a prototype of a huge wheeled tank based on earlier concepts from the 19th century. But instead of building a huge monolithic block tank, they built a tank based on a huge armored cart with twin 27' wheels up front and 2-3 rear wheels of 5' in the back like a giant tricycle! The top of the tank would house 10 crew members in the turret and body of the beast. It would have 12 water-cooled MGs located in two turrets up and under and two sponsors (one on each side) for full coverage. But the tank was underpowered by 2x 250 hp Maybach Sunbeams and was thinly armored and vunerable due to lack of visibility at that height against hidden infantry and artillery below well-camouflaged. It was slow and ackward and could be rammed, its high COG forcing it to tip over. As it was the Tsar Tank got stuck in the mud and was immobilized, making it a sitting duck for heavy howitzers. It was cancelled in 1916 as unpractical and difficult to manufacture. It's name of Netopyr (pipistrella) is from the genus of a bat which came about when the inventors carried the model size by its rear wheels giving the impression of a sleeping bat! What a crazy idea. This is still the biggest tank in terms of height while the German Maus is heaviest at 188-203 tons!!! Germans made a ball tank too in WW2 but shipped it to Japan- the Kugelpanzer made by Krupp. That sits in a museum while the Tsar Tank was scrapped in 1923.

http://strangevehicles.greyfalcon.us/pictured/tsar3.jpg
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