Tanks in the Japanese Army
This article deals with the history and development of tanks of the Japanese Army from their first use after World War I, into the interwar period, during World War II, the Cold War and modern era.
Overview
The First World War established the validity of the tank concept. After the war, many nations needed to have tanks, but only a few had the industrial resources to design and build them. During and after World War I, Britain and France were the intellectual leaders in tank design, with other countries generally following and adopting their designs. Japan took interest in tanks and procured some of the foreign designs, and then went to build its own. Many Japanese designs were of tankettes and light tanks, for use in campaigns in Manchuria and elsewhere in China. During the mid-1930s, the "tank actions" there were mainly against opposing infantry as the Chinese National Revolutionary Army had only three tank battalions consisting of Vickers export tanks, German PzKpfw I light tanks, and Italian CV33 tankettes. 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. Armored vehicle development and fielding suffered as a result; a shift to designs with heavier armor and larger guns to fight against the larger tanks of the Allies came too late for the Japanese to field superior tanks on the battlefield.After the Second World War, the Supreme Commander of the Allied Powers dismantled all military manufacturing and development facilities in Japan, causing Japan to lose the technology base required to manufacture tanks and armored vehicles. However, due to the outbreak of the Korean War, SCAP ordered Japan to re-militarize, forming the Japanese Ground-Self Defense Force and providing M4A3E8 Sherman and M24 Chaffee tanks. For various reasons, including obsolescence of the tanks in JGSDF service at the time, the JGSDF in 1954 was given the option to either purchase new American built M46 Pattons and later the M47 Patton or develop its own Main Battle Tank. The JGSDF decided to develop its own tank, which resulted in the development of the current range of modern Japanese tanks built by Mitsubishi Heavy Industries.
Naming system for tanks
Like all weapons, the year of introduction is the first criteria. That year is computed on the historical calendar of Japan, starting 660 years BC. The Type 89 tank was thus introduced in 1929, the year 2589 of the Japanese calendar. However, several weapons, including tanks, might be introduced in any given year. The Japanese used ideograms to differentiate further the various weapons. The ideogram "Chi" meant a medium tank, "Te" a tankette, "Ke" a light tank, "Ho" a self-propelled gun, "Ka" an amphibious tank. There was a second ideogram to distinguish the models. The Type 97 Chi-Ha is a medium tank introduced in 1937, the Type 2 Ke-To is a light tank introduced in 1942. 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 new turret. The Type 95 light tank had the surname "Ha-Go" that was given by its designer, Mitsubishi Heavy Industries.Post World War I tank designs
After World War I ended, many European countries attempted to mechanize their cavalry. The Japanese cavalry experimented with a variety of armored cars with limited success. These wheeled armored cars were not suitable for most operations in Manchuria, due to the poor road conditions and severe winter climate. Japan's army tried various methods to integrate modern armor into their traditional horse cavalry formations.The Imperial Japanese Army obtained a variety of models from foreign sources as Japan did not have any indigenous tank production capability at that time. These models included one British Heavy Mk IV and six Medium Mark A Whippets, along with thirteen French Renault FTs. The Mk IV tank was purchased in October 1918 while the Whippets and Renaults were acquired in 1919.
The Imperial Japanese Army established an armored force in 1925. Building tanks of their own met several problems, as Japan's priority tended to be with naval procurements so production for tank steel was on a lower level. Development of the first Japanese-designed tank began in June 1925. A team of engineers participated in the development of the medium main battle tank, including a young army officer, Major Tomio Hara. Hara went on to become the head of the tank development department. The design was finished in May 1926 and the prototype was completed by February 1927. After trials, the IJA decided the Type 87 Chi-I was too heavy at 20-ton and too slow to be used as its main battle tank. When the design was rejected, a new requirement was issued for a lighter tank with a nominal weight. The new design was modeled after the Vickers Medium C, which had been bought by the IJA in March 1927. By 1929, the prototype of the Type 89 Chi-Ro was completed. As a result of trials, in 1929 the Japanese decided to develop a small vehicle for mobile operations.
Given its indigenous tank program was still in the prototype stage, in 1930 the Imperial Japanese Army purchased replacements for the Renault FTs; from France, they acquired 10 of the Renault NC1. The army also purchased several Vickers 6-Ton tanks and six Carden Loyd tankettes from the British and used these as a basis for further development.
At first, an indigenous hybrid amphibious car known as the Sumida Amphibious Armored Car was tested in 1930. It had both tracks and wheels and was able to drive in forward and reverse, both in the water and on land. The Japanese cavalry officers were not impressed with the performance, so the amphibious car concept was abandoned. The design was changed to a land tracked vehicle only.
The initial attempt for the tracked vehicle resulted in the Type 92 Jyu-Sokosha Heavy Armoured Car by Ishikawajima Motorcar Manufacturing Company. The Type 92 was designed for use by the cavalry for reconnaissance and infantry support. Production of this first indigenous tankette was plagued by technical problems and only 167 units were built.
The IJA determined that a new tankette was needed, so in 1933 development of the project was given to Tokyo Gas and Electric Industry. The completed 1934 experimental model was a small light tracked vehicle with a turret armed with one machine gun. The design was standardized as the Type 94 tankette, and it was designated for reconnaissance and infantry support. It entered service in 1935, but was later superseded by the Type 97 tankette. Both were "tailored" vehicles for operating in China. There the ultra-light tankettes, with weak armament and armor but highly mobile, proved very successful in infantry support and reconnaissance. However, by the late thirties, it became clear that these type of vehicles would not be very useful against a more serious armed enemy. The development of tankettes was stopped.
By 1932, Mitsubishi Heavy Industries was producing an air-cooled diesel engine that was suitable for tanks. It was placed experimentally into a Type 89. This later became known as the Type 89-B medium tank. Subsequently, Major Tomio Hara designed the suspension system, which was used on many future Japanese tanks. The bell crank scissors suspension paired bogie wheels connected by a coil spring mounted horizontally outside the hull.
, climbing an obstacle
Japan built the Type 95 Heavy Tank in 1934, which was the final version of the Japanese multi-turreted designs, that had started back in 1931 with the prototype 18-ton Type 91 Heavy Tank. Modeled from German and Italian tank designs, the Type 95 featured three turrets; the main armament being a 70 mm cannon with a 6.5 mm machine gun also mounted on the main turret. The two addition turrets gave the Type 95 more firepower: one Type 94 3.7 cm tank cannon was mounted in one auxiliary turret, and the second auxiliary turret featured a 6.5 mm machine gun. Four prototypes were completed before the project was cancelled.
In the meantime, a new light tank known as the Type 95 Ha-Go was produced. Introduced in 1936, it would go on to be produced in greater numbers than any other Japanese tank. It was by no means a bad design, but its popularity among the crews delayed by a couple of years the introduction of a follower. It was already outdated in 1941. The two models that replaced it after 1942 did address the shortcoming of the Type 95, but were still insufficient. A new follower, the Type 5 Ke-Ho would not go further than testing in 1945.
In the field of amphibious tanks, the Japanese proved more creative. The army built several prototypes before the war, but the whole enterprise was dropped by 1940. The Imperial Japanese Navy took over development of amphibious vehicles and in 1941 came up with the Type 2 Ka-Mi, followed in 1943 by the larger Type 3 Ka-Chi. They were adaptations of land tanks on which disposable bows and sterns were added to ensure flotation. They did not play a significant role in combat. Still, in their tank programs the Japanese introduced innovations as they built their designs, including bell-crank suspensions, as pioneers in amphibious tanks, and the use of diesel engines as they were less likely to catch on fire versus the regular gas engines.
World War II
The Japanese generals had made a mistake in their assessment of the tanks used against China, a country whose army had few tanks or antitank weapons. By 1937, Japan fielded 1,060 tanks in 8 regiments, but most were designed for and used in an infantry support role. However, tanks built for this role left the IJA without a tank capable of tank-vs-tank combat, a deficiency that was brought home hard at the Battles of Khalkhin Gol, a terrible defeat inflicted by the Soviet Red Army on the Mongolian border in 1939.During the battles of Khalkhin Gol, the Japanese Army's 1st Tank Corps consisted of the 3rd Tank Regiment and 4th Tank Regiment. The 3rd Tank Regiment consisted of 26 Type 89Bs, four Type 97 medium tanks, seven Type 94 tankettes, and four Type 97 Te-Ke tankettes, and the 4th Tank Regiment contained 35 Type 95s, eight Type 89As, and three Type 94 tankettes. In addition, the IJA infantry and cavalry units had approximately 50 tankettes and armored cars. In this battle, the IJA 1st Tank Corps launched an offensive in July against the Soviet Union's 11th Tank and 7th Armored brigades and suffered heavy losses. After four days of combat, the 1st Tank Corps lost 42 tanks. In the ensuing Soviet counteroffensive in late August, armored units of the Red Army swept around the flanks and attacked the Japanese forces in the rear, achieving a classic double envelopment. By 31 August, Japanese forces on the Mongolian side of the border were destroyed.
The battles of Khalkhin Gol resulted in defeat for the Japanese Sixth Army, and prompted the Imperial Japanese Army to rethink tactics and formations of armored units along with tank design. Armored production was ramped up from 500 tanks per year to 1,200; the Japanese decided they needed a better tank gun and developed the 47 mm Type 1 gun in response to the Soviet 45 mm guns encountered in combat in 1939. This was mounted into the Type 97 and designated the Type 97-Kai a/k/a Type 97 Shinhoto Chi-Ha.
, Philippines, January 1942
From 1932 onwards, the Type 89 Chi-Ro had been the first Japanese tank to be mass-produced. It remained the standard medium tank until the late thirties. It was outdated before that time. Its follower, the Type 97 Chi-Ha took over and remained the standard model type used until the end of the war in 1945. Its shortcomings were clear since the Battle of Khalkhin Gol in 1939 though. The Shinhoto Chi-Ha, the same Type 97 hull with a new turret to install a better gun appeared only in 1942. While vulnerable to opposing Allied tanks, the 47 mm high-velocity gun did give the Shinhoto some fighting chance against them. The 47 mm gun was effective against light tanks and against the sides and rear of the Sherman tank. The Japanese designed additional improved models, but tanks such as the Type 1 Chi-He or the Type 3 Chi-Nu ended up only being produced in limited numbers.
, following surrender in 1945
With the German armor led victories in Europe in 1940, the Japanese changed their deployment and doctrine and organized tank divisions. By 1940 they were the fifth largest tank force in the world behind the Soviet Union, France, Britain and Germany, but were behind in medium and heavy tanks. However, after 1941 the Japanese focused their industry on building warships and aircraft after the attack on Pearl Harbor brought the United States into the conflict, as priorities shifted to warships and aircraft, weapons that were more conducive to naval warfare; attacking across the Pacific, and defending the Empire from the advancing American naval fleet.
So, although the Japanese Army widely employed tanks within the Pacific theater of war, the tanks that Allied forces in the Pacific faced were mostly older designs or even obsolete as the most modern Japanese tanks, such as the Type 3 Chi-Nu, were delayed by material and production shortages. Even after they started to come out of the factories the idea was to hold them for the defense of the mainland, and not dispersed to the far flung army or navy forces. Between 1931 and 1945, Japan produced 6450 tanks. Half of them were made by the Mitsubishi Company. The sub-total of tanks produced between 1940 and 1945 is 4424, i.e. a yearly average comparable to Italy. For a country as large and as industrialized as Japan, that is modest. This being due to the higher priority of steel allocated to the Imperial Navy for warship construction. It changed to a degree in 1944/45, when the homeland became increasingly under direct threat but it was too late. As with many innovative weapons projects launched by Japan in the final years of World War II, production could not advance beyond either small numbers or the prototype stage due to material shortages, and the loss of Japan's industrial infrastructure to the Allied bombing of Japan.
Post World War II
After World War II, Supreme Commander of the Allied Powers ceased all military manufacturing and development plants in Japan, making the country lose the technology to build and manufacture tanks and armoured vehicles. Then due to the Korean War, the Supreme Commander of the Allied Powers ordered Japan to re-militarize, forming armed police forces and provided M4A3E8 Sherman and M24 Chaffee tanks.The M24, though it was popular amongst the Japanese crews, was inadequate when facing Soviet T-34/85s, as seen in Korea. Thus, as the tanks in the Japan ground self-defence force service at the time were obsolete/inadequate, the JGSDF was provided with the option of either purchasing the new American built M46 Patton and, later, the M47 Patton or develop their own MBT in 1954. Due to the high cost of purchasing American made tanks, and because the M47 did not meet their requirements, the JGSDF decided on developing their own main battle tank, resulting in the development of the Type 61 tank.
The first prototype vehicles, STA-1 and STA-2 were built and tested by 1957. The results were used to develop the STA-3 and STA-4. More improvements were made in 1961 and the deployment of the Type 61 began. The initial production rate was low, with only ten tanks produced in 1962, increasing to twenty in 1964 and thirty in 1965 and 1966. A total of 250 had been produced by 1970, with production continuing at an increased pace until 1975 when it was terminated. A total of 560 were produced. The main gun of the Type 61 was unstabilized, so firing on the move was impractical, and the vehicle is not fitted with an NBC protection system or deep wading equipment. The JGSDF started studies on a new tank design with Mitsubishi in 1962, as it was realized that the Type 61 would not be able to defeat the latest Soviet designs like the T-62. The tanks were phased out of service in the 1990s with 400 in service in 1990, and 190 in service in 1995. All were decommissioned by 2000, 39 years after their original deployment. From 1980, Type 61's began to be supplemented by the more modern Type 74 MBT.
The first prototype of the Type 74 MBT, designated STB-1, was delivered in late 1968 and underwent a number of modifications until the final prototype designated STB-6 was delivered in 1973. Production finally started as the Type 74 in September 1975, with 225 being delivered by January 1980. Production ended in 1989, with total production running to 893 examples. The gunner's position included a digital fire control computer, fed range data from the commander's range finder. Rounds for the main gun were upgraded from HEP to APFSDS and HEAT-MP.
After the adoption of the Type 74, the Japanese High Command was already looking for a superior, completely indigenous tank design to defeat the Soviet T-72. As a result, development of a prototype as a replacement for the Type 74, the TK-X MBT began between 1976 and 1977, which became the Type 90 tank.
The Type 90 was to have replaced the Type 74 outright as the Type 74 was generally outdated even before it entered service, but with the ending of the Cold War these plans were scaled back. Requirements of the Type 90 were completed in 1980 with two prototypes and a second series of four prototypes were built between 1986 and 1988 that incorporated changes as a result of trials with the first two prototypes. These were armed with the Rheinmetall 120 mm smoothbore gun also fitted to the German Leopard 2 and, in a modified version, in the US M1A1/M1A2 Abrams MBT.
These second prototypes were used for development and then user trials, all of which were completed by 1989, before Japan formally acknowledged the Type 90 in 1990. With the exception of the 120 mm smooth-bore gun, which is made under license from Rheinmetall of Germany, the Type 90 and its subsystems were all designed and built in Japan. It has been complemented by the Type 10, which first entered service in January 2012. The Type 10 has armor that consists of modular components, which significantly improves the side armor compared to the Type 90. The Type 10 uses the same 120 mm smoothbore gun as the Type 90.
Overview per tank
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 Major Tomio Hara who later became the head of the tank development department. According to Hara, the first tank on the agenda was to develop a medium main battle tank. The team was allocated two years to complete the project. The design aspect was finished in May 1926.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. The prototype was completed by February 1927, within the required period and ready for trials. During the field trials, the 20-ton tank proved to be under-powered. The weight of the initial prototype and its low speed performance did not impress the Imperial Japanese Army General Staff Office, and a new requirement was issued for a lighter tank, with a nominal weight. The new design was modeled after the Vickers Medium C, which had been bought by the Japanese Army in March 1927.
The Chi-I 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, as examples.
Type 94 tankette
The IJA ordered some Carden Loyd tankettes from Great Britain, along with some French Renault UE Chenillette vehicles and field tested them. The IJA determined that the British and French machines were too small to be practical, and started planning for a larger version, the Tokushu Keninsha.The initial attempt resulted in the Type 92 Jyu-Sokosha for use by the cavalry. However, Japanese infantry commanders felt that a similar vehicle would be useful as the support vehicle for transport, scout and communications within the infantry divisions.
An experimental model was completed in 1934. The TK was a small light tracked vehicle with a turret armed with one machine gun. For cargo transportation it pulled an ammunition trailer. After trials in both Manchukuo and Japan, the design was standardized as the Type 94 tankette. It was reclassified as the Type 94 and was designed for "reconnaissance", but could also be utilized for supporting infantry attacks and transporting supplies. It entered service in 1935. The lightweight Type 94 was "tailored" for operating in China. It was used for infantry support and reconnaissance by infantry divisions. The Type 94 tankette proved effective in Manchuria and elsewhere as the Chinese National Revolutionary Army consisted of only three tank battalions to oppose them. As with nearly all nation's tankettes built in the 1920s and 1930s, they had thin armor and could often be penetrated by standard small arms fire.
Variants included the Type 94 Disinfecting Vehicle and Type 94 Gas Scattering Vehicle, which was a Type 94 tankette adapted for chemical warfare. The tankette was used as a "tractor", where it would pull either a configured independent tracked mobile liquid dissemination chemical vehicle or a respective tracked mobile disinfecting anti-chemical agents vehicle. The Gas Scattering Vehicle version could scatter mustard gas chemical agent with an 8m width and the Disinfecting Vehicle version scattered "bleaching powder to counteract the poison gas" or pathogenic agents.
Type 97 Te-Ke tankette
The 'Type 97 Light armored car Te-Ke was a tankette designed as a fast reconnaissance vehicle, and was a replacement for the earlier Type 94 TK.Although the chassis was similar in appearance, the design of the Type 97 was different than the Type 94 in several significant areas. The engine was moved the rear and the gun turret moved to the middle of the tankette, with the driver located to the left side of the hull. This gave the two men a better position to communicate with each other. As with the Type 94, the interior was lined with heat insulating asbestos sheets.
The main armament was the Type 94 37 mm tank gun, with 96 rounds, barrel length of 136 cm, EL angle of fire of -15 to +20 degrees, AZ angle of fire of 20 degrees, muzzle velocity of 600 m/s, penetration of 45 mm/300 m, which was also used by Type 95 Ha-Go. However, due to shortages in the production of this weapon, most vehicles were fitted with a 7.7 mm Type 97 machine gun instead.
The Type 97 replaced the Type 94 on the assembly line in 1939, it was primarily assigned to reconnaissance regiments, and, as with US Army tanks prior to 1941, was not designed to engage enemy tanks. Because it was a reconnaissance vehicle, built for speed, and not direct combat, its hull and turret were designed for only two crewmen; leaving the tankette commander to load and fire the main gun. As with most tankettes it was severely deficient in armor protection, and was prey for any anti-tank weapon of the time.
Variants included the Type 97 Disinfecting Vehicle and Type 97 Gas Scattering Vehicle, which was adapted for chemical warfare. The Type 98 So-Da APC designed for use as an armored personnel and ammunition carrier. Also, the Type 100 Te-Re designed for use as an artillery observation vehicle.
Type 89 Chi-Ro medium tank
The IJA decided that the Type 87 Chi-I was too heavy at 20 tons and too slow to be used as its main tank. 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 6.5mm 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 Type 89 had two variants - the Kō, which used a water-cooled gasoline engine, and the Otsu, with an air-cooled diesel engine and improved frontal armor. Of the two versions, 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. With the Type 89 fast becoming obsolete by the late 1930s, the IJA began a program to develop a replacement tank for infantry support. The IJA was also interested in the lighter and less expensive Type 97 Chi-Ni prototype proposed by Osaka Army Arsenal, which had the same 57 mm gun. However, with the out-break of war with China on 7 July 1937, the peacetime budgetary limitations were removed and the Mitsubishi "Chi-Ha" model was 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. It was armed with a 37 mm main gun and two 7.7 mm machine guns, one in the rear section of the turret and the other hull-mounted. The Type 95 weighed 7.4 tons and had three crewmen.It served throughout the Pacific Theater, including the Second Sino-Japanese War in China, during the Battle of Khalkhin Gol against the Soviet Red Army in 1939, and against the British Army in Burma and India. In addition, it engaged in combat on many Pacific islands, such as Guadalcanal, the Marianas, and Iwo Jima. Several variants were built, among them: the prototype Type 3 Ke-Ri, which mounted a 57 mm Model 97 gun; the Type 4 Ke-Nu, a conversion, re-fitted with the larger turret of the Type 97 Chi-Ha with a 57 mm Model 97 gun; and the Type 5 Ho-Ru, a prototype self-propelled gun similar to the German Hetzer, but with a Type 1 47 mm tank gun.
Type 98 light tank
The Type 98 light tank Ke-Ni was designed to replace the Type 95 Ha-Go light tank. It is also referred to as the Type 98 Chi-Ni light tank by some sources. It was developed in 1938 to address deficiencies in the Type 95 design already apparent from combat experience in Manchukuo and China in the Second Sino-Japanese War. The Imperial Japanese Army General Staff realized that the Type 95 was vulnerable to heavy machine-gun fire––so it determined the development of a new light tank with the same weight as the Type 95, but with thicker armor was needed.Even though the Hino Motors "Chi-Ni Model A" prototype was accepted after field trials as the new Type 98 light tank, series production did not begin until 1942. The Type 98 had a two-man turret, an improvement on the asymmetrical turret used on the Type 95, carrying a Type 100 37 mm tank gun, with a muzzle velocity of and a 7.7 mm machine-gun in a coaxial mount. A total of 104 Type 98s are known to have been built: 1 in 1941, 24 in 1942 and 79 in 1943. One prototype variant built in 1941 was the Type 98 Ta-Se, an anti-aircraft tank that mounted a converted Type 98 20 mm AA machine cannon.
Type 2 Ke-To light tank
The Type 2 Ke-To Light Tank was developed by the Imperial Japanese Army during World War II as an improvement on the existing Type 98 Ke-Ni. Development work on the Type 2 proceeded with an improved Type 1 37 mm gun in an enlarged turret. However, production did not commence until 1944, and by that date Japan was desperate for steel. This, combined with the American strategic bombing campaign that laid waste to the industrial infrastructure, which, when added to the IJN's priority for warship construction, made it clear to the military that the Type 95 light tank would maintain its precedence on the assembly lines. Although obsolete, the Type 95 was cost effective and very reliable. Only 34 Type 2 Ke-To tanks were completed by the end of the war. No Type 2 Ke-To light tanks are known to have engaged in combat prior to Japan's surrender.Type 4 Ke-Nu light tank
The Type 4 light tank Ke-Nu was an innovation created to increase the number of light tanks available to front-line infantry divisions of the Imperial Japanese Army in World War II. Through the modernization of Type 97 Chi-Ha medium tanks, in which its 57 mm gun turrets were replaced with 47 mm high velocity gun turrets, the 57 mm gun turrets were then available to install on Type 95 Ha-Go light tank hulls; thus creating a new light tank.The original version of the Type 97 Chi-Ha medium tank had been armed with a low muzzle velocity 57 mm tank gun. Operational experience against the Soviet Red Army in 1939 revealed that this gun was inadequate against opposing armor, and a new higher velocity 47 mm tank gun was developed. This gun was installed in the Type 97 Chi-Ha medium tank to produce the Type 97-Kai Shinhoto version, which became the standard main battle tank of the Japanese Army. This left a large number of surplus Type 97 Chi-Ha turrets that were later retrofitted onto the chassis of the obsolete Type 95 Ha-Go tank, which had been armed with a 37 mm tank gun. The result gave the tank slightly better firepower, but the retrofitting increased its total weight to 8.4 tons. This reduced the top speed of the tank to 40 km/h. The light tank was designated the Type 4 Ke-Nu and in total, approximately 100 units were converted in 1944.
Type 97 Chi-Ha medium tank
The Type 97 medium tank Chi-Ha was the most widely produced Japanese medium tank of World War II, with about 25 mm thick armor on its turret sides, and 30 mm on its gun shield, considered average protection in the 1930s. The 57 mm main gun was a carry over from the 1933 Type 89 medium tank, and was designed to support the infantry, while the 170 hp diesel Mitsubishi was a capable engine for the tank in 1938. The number of Type 97 medium tanks produced was slightly lower than the output of Type 95 Ha-Go light tanks, but larger than any other medium tank fielded by Japan.Some 3,000 examples of the Type 97 Chi-Ha were produced by Mitsubishi, including several types of specialized tanks. Initially armed with a low-velocity Type 97 57 mm tank gun, but from 1942 on-wards, the Model 97 was equipped with a high-velocity Type 1 47 mm tank gun, mounted in a larger turret. This version was designated Shinhoto Chi-Ha. Type 97 Shinhoto Chi-Ha tanks were first used in combat during the battle of Corregidor Island of the Philippines in 1942. It went on to serve against allied forces throughout the Pacific and East Asia as well as the Soviets during the July–August 1945 conflict in Manchuria. While vulnerable to opposing Allied tanks, the 47 mm high-velocity gun did give the Shinhoto Chi-Ha a fighting chance against them and it is considered to be the best Japanese tank to have seen "combat service" in the Pacific War.
Type 1 Chi-He medium tank
The Type 1 Chi-He was developed in 1942 to replace the Type 97. Compared to the Type 97, the Type 1 Chi-He was slightly longer and taller. Its angled, thicker frontal armor was welded, as opposed to riveted. The adding of the frontal armor and a fifth crewman increased the weight, but the "streamlining" of the hull reduced the increase to only 1.5 tons. Further, its engine generated 70 horsepower more than the Type 97 engine. The newer tank proved to be superior to the Type 97 in both speed and armor protection, but production did not begin until 1943, due to the higher priority of steel allocated to the Imperial Navy for warship construction. A total of 170 units were built from 1943–44, but they did not see combat as they were allocated to the defense of the Japanese home islands. The three-man turret and 47 mm gun of the Type 1 were retrofitted on the modified hull of the Type 97 that the factories were already producing. Even so, production of the tank was discontinued after less than one year in favor of the Type 3 Chi-Nu medium tank.Type 3 Chi-Nu medium tank
The Type 3 Chi-Nu medium tank was urgently developed to counter the American M4 Sherman medium tank. Originally, the next tank in development to replace the Chi-He was the Type 4 Chi-To medium tank. However, the development of the Type 4 Chi-To was delayed, and a "stopgap tank" was needed. The development of Chi-Nu started in May 1943 and was finished by October. The low priority given tanks, along with the raw material shortages meant that the Type 3 did not enter production until 1944. It was the last design based directly on Type 97 lineage.The Chi-Nu retained the same chassis and suspension of the Type 1 Chi-He, but with a new large hexagonal gun turret and a commander's cupola. The main armament, a Type 3 75 mm tank gun, was based on the Japanese Type 90 field gun. The Chi-Nu was the last IJA tank deployed and production continued until the end of the war. The tanks produced were allocated to the Japanese home islands to defend against the projected Allied Invasion.
Type 4 Chi-To medium tank
The Type 4 medium tank Chi-To was one of several new medium and heavy tanks developed by the Imperial Japanese Army towards the end of World War II. It was the most advanced Japanese wartime tank to reach the production phase.The Type 4 Chi-To was a thirty-ton, all-welded tank with a maximum armor thickness of about 75 mm. It was much larger than the Type 97 Chi-Ha, with a longer, wider, tall chassis, supported by seven road wheels. The main armament, a Type 5 75 mm tank gun, was based on the Type 4 75 mm AA Gun that was in turn essentially a copy of a Bofors Model 1929 75 mm AA Gun, housed in a large powered, well-armoured hexagonal gun turret. One Type 97 heavy tank machine gun was mounted in the front hull, and there was a ball mount on the side of the turret for a second one. Two Type 4 Chi-To tanks were completed prior to the end of the war. Neither of the completed units saw combat use.
Type 5 Chi-Ri medium tank
The Type 5 medium tank Chi-Ri was the ultimate medium tank developed by the Imperial Japanese Army in World War II. Intended to be a heavier, lengthened, more powerful version of Japan's sophisticated Type 4 Chi-To medium tank, in performance it was designed to surpass the US M4 Sherman medium tanks being fielded by the Allied forces. It was to be powered by a "Kawasaki Type 98 800 HP engine Ha-9-IIb" detuned for the tank to 550 hp. Originally, the tank was to be fitted with the same Type 5 75 mm tank gun used on the Type 4 Chi-To. Eventually, an 88 mm gun was planned for the turret; a secondary weapon of a front hull-mounted Type 1 37 mm tank gun was fitted in the position normally taken by a machine gun.Along with the Type 4 Chi-To medium tanks, the Type 5 Chi-Ri was originally considered for use in the final defense of the Japanese home islands against the expected Allied invasions. However, the project was abandoned to free up manpower and critical resources to concentrate on the development and production of the more practical Type 4 Chi-To medium tank. As with many innovative weapons projects launched by Japan in the final months of World War II, production could not advance due to material shortages, and the loss of Japan's industrial infrastructure to the allied bombing of Japan. With the end of the Pacific War, an incomplete Type 5 prototype was seized by American forces during the occupation of Japan.
Experimental Type 5 Ho-Ri tank destroyer
The Ho-Ri was a more powerful tank destroyer using a 105 mm cannon in place of the 75 mm design and an additional 37 mm gun. It was to use the Type 5 Chi-Ri tank chassis. The superstructure for the main gun was placed at the rear, the engine was positioned in the center area of the chassis and the driver's station was in the front hull section; all similar in design to the German Ferdinand/Elefant heavy tank destroyer. Another version was to have a twin 25 mm anti-aircraft gun on top of the rear superstructure. According to several sources, no prototypes of the Ho-Ri were known to have been completed.Another planned variant was the Ho-Ri II tank destroyer. It was to use the same Type 5 Chi-Ri tank chassis. The boxy superstructure for the main 105 mm cannon was to be integral with the hull's sides and placed at the center of the chassis.
O-I super-heavy tank
The O-I experimental super-heavy tank had three turrets and weighed 120+ tons, and required a crew of 11 men. It was 10 meters long by 4.2 meters wide with an overall height of 4 meters. The armor was 200 mm at its maximum, and the tank had a top speed of 25 km/h. It had two gasoline engines, and was armed with 1 x 105 mm cannon, 1 x Type 1 47 mm gun, and 3 x Type 97 7.7 mm machine guns. It has been reported that a prototype of the O-I was built in 1943, with the project ending after the tank proved to be "unpractical". However, the exact development history of the O-I prototype is unknown. No images of the O-I are known to exist.Amphibious tanks
During the 1930s and 1940s, the Japanese designed and produced a number of amphibious tank designs. Originally an army project, several experimental models, such as the Sumida Amphibious Armored Car, SR I-Go, SR II Ro-Go and SR III Ha-Go were produced for concept evaluation. Each of the SR series were 3.6 to 7 tonne amphibious tanks, which had 2 to 3 crewmen and were armed with machine guns. In 1940, the Imperial Japanese Navy took over development of amphibious vehicles as it planned a major campaign in the Pacific with amphibious operations and thereby needed vehicles that could support the landings.The Type 1 Mi-Sha a/k/a/ "Type 1 Floating Tank Ka-Mi" was the first IJN prototype produced. Mitisubishi used the knowledge gained from IJA's former SR program. The IJN tanks produced included prototypes such as the Type 1 Mi-Sha and Type 5 To-Ku. Production amphibious tanks included the Type 2 Ka-Mi, and Type 3 Ka-Chi; while other amphibious transports included the F B swamp vehicle, and Type 4 Ka-Tsu APC. All of these for use by the Japanese Special Naval Landing Forces in campaigns in the Pacific.
The Type 1 experimental design led to the Type 2 Ka-Mi, which was based on the Type 95 Ha-Go light tank. The Type 2 Ka-Mi was the first production Japanese amphibious tank, although beginning in 1942 only 182 to 184 units were built. The Type 2 Ka-Mi was first used in combat on Guadalcanal. Later they were encountered by US forces in fighting on the Marshall Islands, and Mariana Islands; particularly on Saipan where they supported the Yokosuka Base Special Naval Landing Forces in its failed amphibious operation. They were also used to support the SNLF during the fighting on the Philippine island of Leyte in late 1944.
The Type 3 Ka-Chi amphibious tank was based on an extensively modified Type 1 Chi-He medium tank and was a larger and more capable version of the earlier Type 2 Ka-Mi amphibious tank. The Type 3 Ka-Chi had the useful capacity to be submarine launched, which enabled it to accommodate the increasingly difficult task of daytime reinforcement for isolated island garrisons in the South Pacific and in Southeast Asia. However, given the fact the main priorities of the navy were in warship and aircraft production, and lacking in any definite plans for additional amphibious operations, production of the Type 3 Ka-Chi remained a very low priority. Only 19 Type 3 Ka-Chi tanks were built during the war. The Type 5 To-Ku was a large, heavy prototype based on the Type 5 Chi-Ri and Type 3 Ka-Chi. It boasted extensive armor protection and was fitted with a Type 1 25 mm gun and front hull mounted a Type 1 47 mm tank gun.
Tank destroyers and assault guns
Type 1 Ho-Ni I Gun tank
The Type 1 Gun tank Ho-Ni I was a tank destroyer and self-propelled artillery developed by the Imperial Japanese Army for use during World War II in the Pacific theater. As units of the Japanese Army began to encounter advanced Allied medium tanks, such as the M4 Sherman, it was seen that the Japanese Type 97 Chi-Ha main battle tank lacked sufficient armor or armament to deal with this threat, and work was begun on a tank destroyer version.The Type 1 Ho-Ni I was developed by utilizing the existing Type 97 chassis and engine, and replacing the gun turret with a 75 mm Type 90 Field Gun mounted in an open casemate with frontal and side armour only, which made it very vulnerable in close combat. The mounting for the 75 mm Type 90 field gun allowed for 20 degrees of traverse to either side and -5 to +25 degrees of elevation. The plan was for self-propelled guns of the Ho-Ni series to form part of a fire support company in each of the tank regiments. Production of the Type 1 Ho-Ni I took place during 1942. It was first deployed in combat during the Battle of Luzon in the Philippines in 1945, but like the rest of the Japanese armor, they were defeated in action against superior US Army forces.
One variant produced was known as the Type 1 Ho-Ni II, which mounted a Type 91 105 mm howitzer. It had a slightly changed superstructure as far as the side armor with re-positioned observation visors. This version entered production in 1943. The total limited number produced of both the Type 1 Ho-Ni I and Ho-Ni II were 80 units.
Type 2 Ho-I Gun tank
The Type 2 Gun tank Ho-I Support Tank was a derivative of the Type 97 Chi-Ha medium tanks of the Imperial Japanese Army in World War II. Similar in concept to early variant of the German Panzer IV, it was designed as a self-propelled howitzer to provide the close-in fire support for standard Japanese medium tanks with additional firepower against enemy anti-tank fortifications.After experience in the war in China, Japanese planners wanted an armored vehicle with a larger weapon would be useful against fortified enemy positions, such as pillboxes. They began work on mounting a Type 41 75 mm Mountain Gun onto the chassis of the Chi-Ha medium tank. The adapted mountain gun, known as the Type 99 75 mm tank gun, was completed in 1940. Thereafter, the short barreled Type 99 75 mm gun was fitted into a Type 97-Kai gun turret on a Type 97 Chi-Ha chassis for the prototype version. The production model utilized the chassis of the Type 1 Chi-He medium tank. As secondary armament there was a single 7.7 mm Type 97 heavy tank machine gun in the hull. For deployment, the gun tank was intended to be used in a fire support company for each of the tank regiments. No Type 2 Ho-I gun tanks are known to have engaged in combat prior to Japan's surrender.
Type 3 Ho-Ni III tank destroyer
The Type 3 Ho-Ni III gun tank was a tank destroyer and self-propelled artillery of Imperial Japanese Army in World War II. The Type 3 Ho-Ni III superseded the Type 1 Ho-Ni I and its variant the Type 1 Ho-Ni II in production. It gave better protection to the crew due to having a completely enclosed superstructure. The Type 3 Ho-Ni III utilized the chassis of the earlier Type 97 Chi-Ha medium tank.The main armament of the Type 3 Ho-Ni III was a Type 3 75 mm tank gun, based on the 75 mm Type 90 Field Gun, which was also used in the Type 3 Chi-Nu medium tank. Previous gun tanks, Type 1 Ho-Ni I and Type 2 Ho-I, were not really optimized designs. The fully enclosed and armored casemate of the Type 3 Ho-Ni III with the Type 3 75 mm tank gun was intended to address these issues, and an order for 57 units was placed with Hitachi Ltd in early 1944. Production was hampered by material shortages, and by the bombing of Japan in World War II, and only 31 to 41 were completed. The Type 3 Ho-Ni III tank destroyers were assigned to various combat units, most stationed within the Japanese home islands to defend against the projected Allied Invasion. As the surrender of Japan occurred before that invasion, there is no record of the Type 3 Ho-Ni III being used in actual combat.
Type 5 Na-To tank destroyer
The Type 5 Na-To was the penultimate tank destroyer developed by the Imperial Japanese Army in the closing stages of World War II. The Type 5 Na-To made use of the chassis of the Type 4 Chi-So armored medium tracked carrier. The superstructure had an open top and rear, with an enclosed armored drivers cab. For the Type 5 Na-To there was added a "shielded platform" for its main gun. Its main anti-tank armament consisted of a Type 5 75 mm tank gun, which was the same gun that was used on the Type 4 Chi-To medium tank. The gun was a variant of the Japanese Type 4 75mm AA Gun.Towards the end of the Pacific War, Japanese field commanders realized that nothing in the inventory of the Japanese Army would be able to withstand the increasingly advanced tanks and armored vehicles fielded by the Allies, and that a more powerful version of the Type 3 Ho-Ni III was necessary. Development was rushed through on a new design, which was completed in 1945. The Japanese Army immediately issued an order for 200 units to be completed in 1945. However, by that time production was impossible due to material shortages, and the bombing of Japan in World War II, and only two units were completed by the surrender of Japan. Neither was used in combat.
German-influenced variants
Throughout the war, Germany supplied blueprints, technological support, and some examples of their tanks to Japan in accordance with the Tripartite Pact signed by the Axis powers. Some of the knowledge shared with Japan inspired or influenced later Japanese armored vehicles, for example:- Type 3 Chi-Nu medium tank, roughly equivalent to Panzer IV tanks
- Type 4 Chi-To medium tank with Type 5 75 mm tank gun; a variant of the Type 4 75 mm AA Gun, inspired by the Panther tank
- Type 5 Chi-Ri heavy tank with Type 99 88 mm AA Gun, inspired by the Tiger I.
- Type 1 Ho-Ha halftrack, inspired by the Sd.Kfz. 251
Post World War II tanks