O-I super-heavy tank

O-I
Diagram illustrating the interior side view of the O-I
TypeSuper-heavy tank
Place of originEmpire of Japan
Production history
Designed1940 (100-ton O-I),
1944 (120+ ton O-I)
Producedincomplete prototype
No. built1 incomplete prototype
Specifications
Mass120+ tons
Length10.12 m
Width4.84 m
Height3.63 m
Crew11

Armormaximum of 150 mm
Main
armament
Type 92 105 mm/L45 gun
Secondary
armament
2 x 70 mm guns in the two front hull sub-turrets and 2 x Type 97 7.7 mm machine guns in a rear sub-turret.
EngineTwo V-12 gasoline engines
550 hp (410 kW) x2
Power/weight8.33 hp/t
Suspensioncoil springs
Maximum speed 25 km/h

O-I was the designation given to a proposed series of Japanese super-heavy tanks designed during World War II. The vehicle was planned to be very heavy and have a crew of 11. The complete history of the O-I is unknown, due to the “obscure” nature of the project and the limited documentation that survived post-war.