Super-heavy tanks were designed in response to the arms race of ever-increasing armament and armor in tanks. Although some models were built, they were impractical and saw no active service or combat. Most heavy tanks suffer from problems related to tactical mobility (soft ground, crossing bridges), strategic mobility (transporting on rail or truck), reliability of mechanical components under severe stresses, and other practical problems, like the sheer difficulty of handling extremely large ammunition. Above a certain weight threshold these problems become insurmountable.
Some extreme tank designs approved by Adolf Hitler during World War II were devised to be all-conquering monsters of the battlefield. A prime example of these would have to be the Maus, a German design which only reached the prototype stage. These tanks were designed by the Nazis as a possible way of winning the war and by the allies as a way of countering any advances in enemy armor.
At the time they seemed sensible as both sides could see the others tanks and anti-tank weapons improving and both required a way of countering the others superiority. Hitler was a keen advocate of super-heavy AFVs and personally agreed to the development of the Maus whereas in Britain and America the stunning effectiveness of the German 88mm's forced home the point that much thicker armor and much better armament was needed on their own tanks.
Ultra-heavy tanks of 1,000 tonnes or heavier were even considered, including the Landkreuzer P. 1000 Ratte, an enormous and unconventional tank, and the Landkreuzer P. 1500 Monster, a gigantic self-propelled artillery platform. These were deemed impractical and neither was built, as Albert Speer quickly put an end to these fearsome but fantastical behemoths.
The idea of super heavy tanks saw less development after the war, except in the Soviet Union where some relatively heavy tank prototypes were tested for the Cold War nuclear battlefield. These might be considered super-heavy by the standards of Soviet tank design, where the emphasis was on small size and low weight, but they were no heavier than the standard U.S. and British heavy tanks of the period.
- Could be armed with a heavier complement of weaponry than other tanks
- Could carry heavier armor than other tanks
- Frightening appearance may cause a psychological advantage
- Were very heavy (buckled roads, couldn't cross lighter bridges)
- Generally unreliable (sheer weight caused problems for gears, running tracks, and power pack)
- Very costly (one could purchase four Stug III for the price of one Tiger I at the same cost-effectiveness. Now consider the Maus's cost)
- Very slow
- Difficult to deploy (most ShTs required special rail transports i.e Pzkpfw VIII Maus, Tortoise, and T-28)
- High supply requirements
List of Super Heavy Tanks
American super-heavy tanks
- T-28 Super Heavy Tank (95 tonnes, 2 prototypes)
British super-heavy tanks
- Tortoise (tank) (78 tonnes, 6 prototypes)
- TOG1 (tank) (80 tonnes, 1 prototype)
- TOG2 (tank) (80 tonnes, 1 prototype)
French super-heavy tanks
German super-heavy tanks
- K-Wagen (120 metric tons, project only)
- Jagdtiger (71.7 tonnes, only super-heavy tank to have seen combat, 88 produced in total)
- Panzer VII Löwe (76–90 tonnes, project only)
- Panzer VIII Maus (188 tonnes, 2 prototypes)
- E-100 (tank) (140 tonnes, 1 hull completed)
- Landkreuzer P. 1000 Ratte (1800 tonnes, project only)
- Landkreuzer P. 1500 Monster (2500 tonnes, project only)
Soviet super-heavy tanks
- Grotte Tank (TG-5 or T-42, 100 tonnes with 107mm main gun and four subturrets. project only - 1931—Zaloga 1984:85)
- Obyekt 279 (60 tonnes, one prototype, two planned - 1957)
Japanese super-heavy tanks
- Experimental O-I Super HeavyTank (130 tonnes. Purportedly one prototype was produced in 1944 and sent to Manchuria.)
- Experimental O-I Ultra HeavyTank (modification of the O-1 Super Heavy Tank with four turrets)
- Zaloga, Steven J., James Grandsen (1984). ''Soviet Tanks and Combat Vehicles of World War Two'', London: Arms and Armour Press. ISBN 0-85368-606-8.