Panzerkampfwagen VIII Maus (English: 'mouse') was a German World War II super-heavy tank completed in late 1944. It is the heaviest fully enclosed armored fighting vehicle ever built. Five were ordered, but only two hulls and one turret were completed, the turret being attached before the testing grounds were captured by advancing Soviet military forces. This vehicle was also built to compete with the Soviet heavy Kliment Voroshilov tank.
These two prototypes underwent trials in late 1944. The complete vehicle was long, wide and high. Weighing 188 metric tons, the Maus's main armament was the Krupp-designed 128 mm KwK 44 L/55 gun, based on the 12.8 cm Pak 44 towed anti-tank gun also used in the casemate-type Jagdtiger tank destroyer, with a coaxial 75 mm KwK 44 L/36.5 gun. The 128 mm gun was powerful enough to destroy all Allied armored fighting vehicles in service at the time, with some at ranges exceeding .
The principal problem in the design of the Maus was developing an engine and drivetrain which was powerful enough to adequately propel the tank, yet small enough to fit inside it – as it was meant to use the same sort of "hybrid drive", using an internal-combustion engine to operate an electric generator to power its tracks with electric motor units, much as its Porsche-designed predecessors, the VK 30.01 (P), VK 45.01 (P), and Elefant had. The drivetrain was electrical, designed to provide a maximum speed of and a minimum speed of . However, during actual field testing, the maximum speed achieved on hard surfaces was with full motor field, and by weakening the motor field to a minimum, a top speed of was achieved. The vehicle's weight made it unable to use most bridges; instead it was intended to ford to a depth of or submerge up to a depth of and use a snorkel to cross rivers.
The Maus was intended to punch holes through enemy fortifications in the manner of an immense "breakthrough tank", while taking virtually no damage to any components.
Development
The development of the Maus originates from a contract given to Porsche for the design of a 100-ton tank in March 1942. Porsche's design, known as the VK 100.01 / Porsche Type 205, was shown to Adolf Hitler in June 1942, who subsequently approved it. Work on the design began in earnest; the first prototype, to be ready in 1943 was initially to receive the name Mammut ('mammoth'). This was reportedly changed to Mäuschen ('little mouse') in December 1942 and finally to Maus ('mouse') in February 1943, which became the most common name for this tank.
The Maus was designed from the start to use the "electric transmission" design which Ferdinand Porsche had used in the VK 4501 (P), his unsuccessful attempt to win the production contract for the Tiger. The initial powerplant was the Daimler-Benz MB 509 gasoline engine, an adaptation of Germany's largest displacement (at inverted V12 aircraft engine, the Daimler-Benz DB 603 petrol engine, and later changed to the Daimler-Benz MB 517 diesel engine. This drove an electrical generator, and their combined length occupied the central/rear two-thirds of the Maus' hull, cutting off the forward driver's compartment in the hull from direct access to the turret from within the tank. Each 1.1-meter-wide track, which used the same basic "contact shoe" and "connector link" design format as the Henschel-built Tiger II, was driven by its own electric motor mounted within the upper rear area of each hull side. Each set of tracks had a suspension design containing a total of 24 road wheels per side, in six bogie sets, staggered to be spread over the entire width of the track.
Due to the return "run" of the uniquely 110 cm-wide tracks used being completely enclosed within the fixed outer side armor panels that defined its overall hull width, with the inner vertical lengthwise walls of the hull used to mount the suspension components, a narrow lengthwise "tub" remained between the hull's inner armored walls, under and to the rear of the turret to house the engine and generator of the tank's powertrain.
The armor was substantial: the hull front was thick, the sides and rear of the hull were up to . The turret armor was even thicker, the turret front was up to and the sides and rear . The gun mantlet was , and combined with the turret armor behind, the protection level at that section was even higher.
The initial plan for the Maus was for the prototype to have been completed by mid-1943, with monthly production scheduled to run at ten vehicles per month after delivery of the prototype. The work on the Maus would be divided between Krupp, responsible for the chassis, armament and turret and Alkett, who would be responsible for final assembly.