The Type 97 Chi-Ha was a medium tank used by the Imperial Japanese Army during the Second Sino-Japanese War, at Nomonhan against the Soviet Union, and in the Second World War. It was the most widely produced Japanese medium tank of World War II, although the armor protection was considered as average in the 1930s. The 57 mm main gun, designed to support the infantry, was a carry over from the 1933 Type 89 medium tank. Later it was replaced by 47 mm gun more effective against enemy armor. The 170 hp Mitsubishi engine was a capable engine for the tank in 1938, and – notably for the time – it was a nonflammable diesel. After 1941, the tank was considered less effective than most Allied tank designs.
The Type 97's low silhouette and semicircular radio antenna on the turret distinguished the tank from its contemporaries. The crude suspension was derived from the Type 95 Ha-Go light tank, but used six road wheels instead of four.| Type 97 Chi-Ha | |
|---|---|
| Place of origin |  Empire of Japan |
| Production history | |
| Designed | 1936 |
| Produced | 1938–1943 |
| Number built | 1,162 (plus 930 of Type 97-Kai) |
| Variants | Type 97-Kai Chi-Ha |
| Specifications (Type 97 Chi-Ha as of 1941) | |
| Weight | 15 tonnes (14.76 tons) |
| Length | 5.50 meters |
| Width | 2.34 meters |
| Height | 2.33 meters |
| Crew | 4 |
| | |
| Armor | 8–26 mm (33 mm on gun mantlet) |
| Main armament | 57 mm Type 97 gun |
| Secondary armament | two 7.7 mm Type 97 machine guns |
| Engine | Mitsubishi Type 97 diesel (V-12, 21.7 litres) 170 hp (127 kW)/2,000rpm |
| Power/weight | 11.3 hp/tonne |
| Suspension | Bell crank |
| Operational range | 210 kilometers |
| Speed | 38 km/h (24 mph) |
Type 97 hull was of riveted construction with the engine in the rear compartment. In the forward compartment, the driver sat on the right, and bow gunner on the left. The commander's cupola was placed atop the turret. Internal communications were by 12 push buttons in the turret, connected to 12 lights and a buzzer near the driver.
The Type 97 was initially equipped with a Type 97 57 mm main gun, the same caliber as that used for the earlier Type 89 I-Go tank. The cannon was a short-barreled weapon with a relatively low muzzle velocity, but sufficient as the tank was intended primarily for infantry support. The gun had no elevation gear.
The tank carried two 7.7 mm Type 97 machine guns, one on the front left of the hull and the other in a ball mount on the rear of the turret. The latter could not be remounted on top of the turret for anti-aircraft use. The turret was capable of full 360-degree traverse, but the main gun had a second pair of trunnions, internally allowing a maximum 10-degree traverse independently of the turret.
The thickest armor used was 33 mm on the gun mantlet and 26 mm on the turret sides.
Power was provided by an air-cooled "V-12 21.7 liter diesel Mitsubishi Type 97" engine, which provided 170 hp (127 kW). The engine designation was SA12200VD.
Development of the improved Shinhoto Chi-Ha
The shortcomings of the Type 97, with its low-velocity 57 mm gun, became clear during the 1939 Nomonhan Incident against the Soviet Union: the 45 mm gun of the Soviet BT-5 and BT-7 tanks outranged the Japanese tank gun, resulting in heavy Japanese losses. This convinced the Army of the need for a more powerful gun, and development of a new 47 mm weapon began in 1939 and was completed in 1941. The Type 1 47mm tank gun was designed specifically to counter the Soviet tanks. The 47 mm gun's longer barrel generated much higher muzzle velocity, resulting in armor penetration superior to that of the 57 mm gun. The new version, designated Type 97-Kai Shinhoto Chi-Ha, replaced the original model in production in 1942. It had a new, larger turret – as a side note, a considerable number of existing 57-mm-gun turrets was subsequently re-used to create Type 4 Ke-Nu light tank.
