Panzer VIII Maus

• Role: Heavy Tank
• Manufacturing Nation: Germany
• Introduced: 1944
• Crew: 6
• Maximum speed: 13 km/h (8 mph)
• Operational Range: 160 km on roads/62 km off road (99 miles/38miles)
• Weight: 192 Metric Tons
• Main Gun: 128mm Cannon
• Secondary Armaments: 75 mm KwK 44 L/36.5 gun and a 7.92 mm MG34

The Panzer VIII Maus was a true behemoth. With between 60-210mm of armor, it was nearly indestructible, but its massive weight reduced its mobility and limited the roads and bridges it could use. As a result an alternative system was developed, where the Maus would instead ford the rivers it needed to cross. Due to its size it could ford relatively deep streams, but for deeper ones it was to submerge and drive across the river bottom. The solution required tanks to be paired up. One Maus would supply electrical power to the crossing vehicle via a cable until it reached the other side. The crew would receive air through a large snorkel, which was long enough for the tank to go 45 feet (13 m) underwater. The Panzer VIII Maus never advanced beyond the prototype stage, although the original contract called for 150, as well as plans for an anti-aircraft version with twin eighty-eights. One prototype was captured by the Soviets, but few design ideas were adopted by the Russians, who strictly limited the weight and size of their tanks.

T-100

• Role: Super Heavy Tank
• Manufacturing Nation: USSR
• Introduced: 1939
• Crew: 8
• Maximum speed: 36 km/h
• Operational Range: 200 km
• Weight: 58 Tons
• Main Gun: 76.2mm type L-11 gun (center turret)
• Secondary Armament: 45mm gun (forward turret)

The T-100 was a twin-turreted Soviet heavy tank prototype was designed in 1938-39 to be a super-heavy breakthrough tank. The original specification was for a five-turreted "anti-tank gun destroyer" which would resist 37mm guns at any range and 76.2mm guns at 1,200 m. This was reduced to two turrets and featured thick, welded armor, radios, and torsion bar suspension. The T-100 tank sported two turrets placed on a very long chassis. The front turret, mounting a 45mm antitank gun, was placed at a lower elevation than the other, thus giving the front turret a limited area of fire. The top turret, mounting a 76.2mm gun, was able to turn a full 360 degrees. A prototype was used in the Winter War against Finland. A self-propelled gun variation was also designed. Ultimately, the Soviets chose to focus on smaller, lighter, more mobile tanks.

Tortoise A39

• Role: Heavy Assault Tank
• Manufacturing Nation: United Kingdom
• Introduced: 1944
• Crew: 7
• Maximum speed: 19 km/h (12 mph) (road), 6 km/h (3.7 mph) (offroad)
• Operational Range: 140 km (87 mi) (road)
• Weight: 78 Tons
• Main Gun: 94mm Gun
• Secondary Armaments: three 7.92 mm Besa Machine Guns

The Tortoise (A39) was a British heavy assault tank design developed in World War II but never put into production. In the early part of 1943 the Allied forces anticipated considerable resistance in the projected future invasion of Europe, with the enemy fighting from heavily fortified positions such as the Siegfried Line. As a result, a new class of vehicles emerged, in the shape of assault tanks, which placed maximum armor protection at a higher priority than mobility. The 32-pdr gun was mounted in a power-assisted limited traverse mounting; rather than being mounted on the more traditional trunnions, it protruded through a large ball mount in the front of the hull, protected by 225 mm armor. 25 were initially ordered, but following the end of the war the order was reduced and only 6 vehicles were built. In trials it was found to be mechanically reliable and a powerful and accurate gun platform, however at a weight of 80 tons and a height of 10 feet (3.0 m) it proved difficult to transport.

O-I

• Role: Super Heavy Tank
• Manufacturing Nation: Japan
• Introduced: 1944
• Crew: 11
• Maximum speed: 25 km/h
• Weight: 130 Metric Tons
• Main Gun: 105mm Gun
• Secondary Armaments: 37 mm Type 1 gun, three 7.7 mm machine guns

O-I was the name given to a proposed series of Japanese super-heavy tanks, to be used in the Pacific Theater. The vehicle was monstrous, carrying 11 crew in its 120-ton body, but only one model was rumored to have been built in 1944 and afterward sent to Manchuria. Exact information is lacking however, and it is unknown whether it ever saw combat. The original plans called for three turrets for the one large cannon and two smaller guns. They also had planned a more advanced experimental prototype, the Ultra-Heavy Tank OI, which featured no fewer than four turrets. It is unlikely that the Ultra-Heavy was ever actually built.

FCM-F1

• Role: Super Heavy Tank
• Manufacturing Nation: France
• Introduced: 1940
• Crew: 9
• Maximum speed: 20 km/h
• Operational Range: 200 km
• Weight: 139 Metric Tons
• Main Gun: 90mm Gun
• Secondary Armaments: 47mm SA37 gun and six machine guns

When the Second World War broke out in September 1939 some hurried measures were taken to have an operational heavy tank ready for the planned offensive against Germany in 1941. Despite the urgency of events in Europe, the FCM-F1 was the subject of numerous committees and redesigns which tried to reconcile the limitations of the country's bridges with the armor required to stop shells from German 88's. In May 1940, a potential final design was scrapped because there was no suitable 135mm gun available. Within weeks, the Germans invaded and conquered France and all official design on the FCM-F1 was halted.

T-28

• Role: Super Heavy Tank
• Manufacturing Nation: United States
• Introduced: 1945
• Crew: 4
• Maximum speed: 12 mph (19.3 km/h)
• Operational Range: 100 mi (160 km)
• Weight: 95 Tons
• Main Gun: 105 mm T5E1 gun, with 62 rounds
• Secondary Armament: .50 Cal Machine Gun

The T28 was first conceived in the spring of 1945, too late to be used in World War II. The original plans called for five prototype vehicles to be built, and eventually for a total of twenty-five tanks to be constructed. The T28 had no conventional turret, instead it had a casemate style hull, giving it a comparatively low profile. Its main armament was a 105 mm T5E1 gun in a ball-shaped gun mantlet set into the hull front. Because this vehicle did not have a turret, the T28 was redesignated as the T95 Gun Motor Carriage, but in June 1946 the vehicle was, again, redesignated Super Heavy Tank T28. It has been argued that it was neither a super-heavy tank nor a self-propelled gun, but that it was in fact a very heavy tank destroyer intended for German heavy tanks.