The Imperial Japanese Army (IJA) initially purchased foreign tanks for evaluation during World War I, and began developing its own indigenous designs during the late 1920s.
Due to the war with China, Japan produced a large number of tanks. Although initially the Japanese used tanks to good effect in their campaigns, full-scale armored warfare did not occur in the Pacific and Southeast Asian theaters as it did in Europe, and tank development was neglected in favor of naval activities. Later, during the last year of World War II the newest and best Japanese designs were not used in combat; they were kept back in expectation of defending the Japanese Home Islands.
Initial tank procurement
Near the end of World War I, the Japanese showed an interest in armored warfare and tanks and obtained a variety of models from foreign sources. These models included one British Heavy Mk IV and six Medium Mark A Whippets, along with thirteen French Renault FTs (later designated Ko-Gata Sensha or "Type A Tank"). The Mk IV was purchased in October 1918 while the Whippets and Renaults were acquired in 1919.
Trials with these vehicles were successful, and the army decided to establish an armored force in 1925, planning to form three light tank battalions and one heavy tank battalion. However, the greatest problem was equipping these units, as the Japanese did not have any indigenous tank production capability at that time. The IJA therefore sent a mission to purchase more tanks from Britain and France, requesting newer designs. However, the newer tanks were not available as these countries had difficulties supplying them to their own armored forces, and the only available model was the older Renault FT. The Japanese reluctantly imported the Renault FT tanks. In March 1927, the IJA also bought a Vickers Medium C to use for design study. During trials, the gasoline engine of the Vickers C caught fire, leading the Japanese design team to call for a diesel engine for use in indigenous produced tanks. Then in 1930 they were able to acquire ten examples of its successor, the Renault NC1 (designated Otsu-Gata Sensha or "Type B Tank"). Both types of tanks were still in active service in 1940, and additional vehicles and spare parts were obtained after the Japanese occupation of French Indochina. The Japanese also purchased several Vickers 6-Ton tanks and Carden Loyd tankettes and used these as a basis for further development in tanks.
Doctrine
As with the Americans and the Italians, the Japanese originally adopted French-designed tanks, and were influenced by their doctrines and employment. As with many other nations at the time, the Japanese viewed the tank as a tool largely used in direct support of their infantry, and were rarely allowed independent action. During the Second Sino-Japanese War, Japanese tanks were successful, especially as the Chinese had no significant armoured forces of their own.
With their defeat by the Soviet Union at Nomonhan in 1939, the Japanese began to rethink their tank designs and doctrine, although their emphasis would continue to remain on supporting the infantry. However, with the beginning of the Pacific War, Japan's priorities shifted to warship and aircraft production, and resources for the production of armored vehicles for the Army were diverted or curtailed.
In addition, the terrain of Southeast Asia and the islands of the Pacific were in general not suited to armored warfare, being largely tropical rainforests. Aside from the invasion of Malaya, and the Philippines, large-scale Japanese use of tanks was limited during the early years of the war and therefore development of newer designs were not given high priority as the Japanese strategy shifted to a "defensive orientation" after the 1941-42 victories.
Older tanks continued to be used as defensive emplacements and infantry support weapons. Advanced Japanese tank designs, which could challenge Allied tanks did not appear until the close of World War II; as with many innovative weapons projects launched by Japan in the final years of the war, production could not advance beyond either small numbers or the prototype stage due to material shortages, and the loss of Japan's industrial infrastructure by the Allied bombing of Japan.
Naming system for tanks Like all weapons, the year of introduction is the first criterion. A tank's designation contains the last two digits of the Japanese imperial year, which has its origin at 660 BC. For example, the designation "Type 89" corresponds to imperial year 2589, which is 1929 in the Gregorian calendar.
However, several weapons, including tanks, might be introduced in any given year. The Japanese used ideograms to differentiate further the various weapons. The first ideogram indicated the category of the vehicle. It was a katakana syllable that corresponded to the first syllable of the category. Thus, the katakana syllable stood for a light tank, as it is the first syllable of the corresponding Japanese term, . Analogously, meant a medium tank, a tankette, a self-propelled gun, and an amphibious tank. +AbbreviationLong formMeaningmedium tanklight tankgun tankamphibious tank = TK, see Type 94 tankettetankette standing for super-heavy tank There was a second ideogram to distinguish the models. This character is another katakana syllable that represents an ordering according to the Iroha sequence and can be thought of as a, b, c, … or first, second, third, and so on.
For example, the Type 97 Chi-Ha is a medium tank introduced in 1937 and the third medium tank, the Type 2 Ke-To is a light tank introduced in 1942 and the seventh light tank. There is sometimes a surname to supplement or replace the ideograms. The "Type 97 Shinhoto Chi-Ha" is a variation of the medium tank Chi-Ha with a . The Type 95 light tank had the surname that was given by its designer, Mitsubishi Heavy Industries.
Japanese designs For both security and logistical reasons, certain officers and engineers in the Japanese Army Technical Bureau during the early 1920s were adamant that future tanks should be made in Japan. General Suzuki (chief of the Technical Bureau) protested at the Ministry of War decision to purchase foreign designs, which ultimately led to that decision being reversed. A special committee of the Imperial General Staff (Daihonei) worked on the feasibility of indigenous design and development of Japanese armor.
However, indigenous design and production of armored vehicles would prove to be difficult, due to minimal experience with military motor vehicle design (the engineers had only designed several types of trucks and one type of tractor), along with low priority for tank steel production. Moreover, the first design had to be completed in only two years or the program would be canceled.Taki's Imperial Japanese Army: "The Development of Imperial Japanese Tanks"
Type 87 Chi-I (Experimental tank No.1)
Development of the first Japanese-designed tank began in June 1925. A team of engineers of the Technical Bureau participated in the development, including a young army officer, Major Tomio Hara. Hara later became the head of the tank development department and rose to the rank of general. According to Hara, the first tank on the agenda was to develop a medium main battle tank. The team started their design and worked hard to complete the project within the two years allocated. As this was the first tank designed in Japan, they had to begin with almost every component built from scratch.
The design was completed in May 1926 and production was ordered to begin at the Osaka Army Arsenal. At the time, there was little heavy industry allocated to the production of motor vehicles in Japan, so there were significant difficulties creating the prototype. Experimental tank No.1 a/k/a Type 87 Chi-I was completed by February 1927. The 20-ton tank underwent field trials, but proved to be under-powered. The weight of this initial prototype and its low speed did not impress the Imperial Japanese Army General Staff Office, so a new requirement was issued for a lighter tank, with a nominal weight. The new design was modeled after a Vickers Medium Mark C tank, which had been purchased by the Japanese Army in March 1927. Along with the Osaka Army Arsenal, Sagami Army Arsenal was also assigned to oversee the design and manufacture of assorted types of armored vehicles and tanks.
The tank had a complex parallelogram suspension system with two pairs of road bogie wheels per leaf spring arrangement. Hara designed a bell crank scissors suspension that paired the bogie wheels and connected them to a coil spring mounted horizontally outside the hull. This suspension became standard on the majority of the subsequently designed Japanese tanks and can be seen on the Type 95 Ha-Go light tank and Type 97 Chi-Ha medium tank, as examples.
Type 89 Chi-Ro medium tank
The IJA decided that the Type 87 Chi-I was too heavy and slow to be used as its main tank, so the Type 89 Chi-Ro was developed to overcome these shortcomings. The new design weighed 12.8 tons and used stronger and lighter steel plate instead of the Type 87's iron armor. Armament was a Type 90 57 mm gun, along with two Type 91 6.5 mm machine guns. The Type 89 prototype was completed in 1929, with production starting in 1931, making this the first tank to be mass-produced in Japan. The designation is also known as the Type 89 "I-Go" and sometimes transliterated "Yi-Go".
The Type 89 had two variants - the Kō ("A"), which used a water-cooled gasoline engine, and the Otsu ("B"), with an air-cooled diesel engine and improved frontal armor. Of the two versions made, a total of 113 Kō tanks and 291 Otsu tanks were produced. The Type 89 served with Japanese infantry divisions and first saw combat use in China during the First Battle of Shanghai in 1932. It was deployed for operations in the Second Sino-Japanese War, beginning in 1937. However, by the late 1930s the Type 89 was shown to be fast becoming obsolete. The IJA therefore began a program to develop a replacement tank for infantry support and with the out-break of war with China, the peacetime budgetary limitations were removed. The Mitsubishi "Chi-Ha" model was thereby accepted as the new Type 97 medium tank by the army as the replacement for the Type 89.
Type 95 Ha-Go light tank
The Type 95 Ha-Go was a replacement for the Type 89 medium tank, which was considered too slow for mechanized warfare. The prototypes were built by Mitsubishi and production was started in 1936, with 2,300 completed by the end of the war. The initial version was armed with a Type 94 37 mm main gun and two Type 91 6.5 mm machine guns. From 1937 forward, it was armed with a longer barrel 37 mm main gun and two Type 97 7.7 mm (0.303 inch) machine guns, one in the rear section of the turret and the other hull-mounted. The changes in armament caused the weight of the tank to increase to 7.4 tons. The Type 95 Ha-Go had a crew of three.
Type 95 Ha-Go tanks served during the Battle of Khalkhin Gol (Nomonhan) against the Soviet Red Army in 1939, against the British Army in Burma and India, and throughout the Pacific Theater during World War II. On 22 December 1941 the Type 95 light tank earned the distinction of being the first tank to engage in tank vs tank combat with US manned American tanks (M3 Stuart light tanks in the Philippines) during World War II; and the only enemy tanks to have ever landed on North American soil during any war.
Several variants were built, among them: the prototype Type 3 Ke-Ri, which mounted the Type 97 57 mm tank gun; the Type 4 Ke-Nu, a conversion, re-fitted with the larger Type 97 Chi-Ha medium tank turret and its Type 97 57 mm tank gun; and the Type 5 Ho-Ru, a prototype casemate-hulled turretless self-propelled gun similar to the German Hetzer, but with a Type 1 47 mm tank gun.
Type 97 Chi-Ha medium tank