The Allies weren’t the only ones in World War II who had some bizarre ideas up their sleeves. Adolf Hitler particularly desired an indestructible superheavy tank. He proposed it in 1942, but few others at the top of the German military shared his enthusiasm for the idea. The Maus (“mouse”) was a 200-ton behemoth of a tank designed by Ferdinand Porsche, but it was plagued with mechanical problems from the start.
The driveshaft especially suffered from constant failures. Despite a massive Daimler-Benz aircraft engine powering the motors, the tank’s top speed was only 19 kilometers per hour (12 mph). It featured armor that was more than 23 centimeters (9 in) thick, but the Maus didn’t have a single machine gun to make it suitable for close combat—and the considered opinion of the top German brass was that it would find itself in close combat often.
There were plans to make 150 of these tanks, but the concerns of the generals couldn’t be overcome. In the end, only two prototypes were completed.