OI (tank)
| OI | |
|---|---|
| General properties | |
| crew | 11 |
| length | 10 m |
| width | 4.2 m |
| height | 4 m |
| Dimensions | 120+ t |
| Armor and armament | |
| Armor | Max. 150-200 mm |
| Main armament | Type 96 15 cm howitzer or Type 92 10 cm cannon |
| Secondary armament | two 47 mm Type 1 anti-tank guns , 7.7 mm Type 97 machine guns |
| agility | |
| drive | two V-12 engines 121 kW (550 PS) |
| Top speed | 25 km / h |
| Power / weight | |
OI was a planned super-heavy Japanese tank from the time of World War II . O stands for "Ooki-I-gou", Japanese for "big", I for "first".
After the fighting on Chalin Gol in May – September 1939 with the Red Army , the Imperial Japanese Army believed that a super-heavy tank, like a moving fortress, would be necessary in the future. The contract was awarded to Mitsubishi . At Mitsubishi, the project was called Mi-To , Mi for Mitsubishi, To for Tokyo .
Designed as a multi-turn armor, it had smaller towers next to the main tower, which were to be attached to the hull at the front and rear . The weight was 120 to 150 tons. The vehicle was suspended by the coil springs attached to rollers . As drive two modified were BMW VI - aircraft engines provided by Japan as Kawasaki built Ha-9 under license. The engine was also intended for the Type 5 Chi-Ri . Two of these air-cooled petrol engines should be housed in parallel in the rear. A reinforced version of the one used in the Type 97 Chi-Ha was planned as the transmission . According to the construction plans, the main tower was equipped with a Type 96 15 cm howitzer . Two small turrets on the front of the hull each accommodated a 47-mm Type 1 anti-tank gun ; Another turret at the stern accommodated two heavy Type 97 machine guns . According to other statements, the main armament was the Type 92 10 cm cannon . There are also various statements about armor. Accordingly, the front armor was 75 mm with an additional armor plate of 75 mm. The side armor was 35 mm with additional 35 mm thick aprons that protruded over the upper chains. Other sources report a maximum of 200 mm front and 110 mm side armor.
The experiments with an unfinished prototype were probably carried out on August 1, 1943 in the Sagami Arsenal . After the suspension was destroyed in the experiment, the design was abandoned and the prototype was scrapped . The only remnant that has been preserved is a 0.8 m wide link of the track . This was in a shrine in Fujinomiya for a long time before it was brought to the Camp Takigahara military facility of the Japanese Ground Self-Defense Forces .
The information on this tank project was mainly based on the statements made by the developers involved after the war. Some original development documents were only published at the end of 2016. In the literature you can also find the statement that the prototype of a 100-ton tank was manufactured in 1940 but the project was no longer pursued. In 1944 the project would have been resumed under the name OI , but canceled because of the poor war situation. According to the new documents, it is the same project.
literature
- Kenneth Estes: Super-heavy Tanks of World War II . Osprey, 2014, ISBN 978-1782003830 .
- Andrzej Tomczyk: Japanese Armor Vol. 4 . AJ Press, 2005, ISBN 978-8372371676 .
- Steven J. Zaloga : Japanese Tanks 1939-45 . Osprey, 2007, ISBN 978-1-8460-3091-8 .
website
- Super heavy tank "OI". Taki's Page, accessed February 7, 2019 .
- OI Superheavy Tank: A Complete History