Type 98 Ke Ni

History and development

The Type 98 developed in 1938 was a light tank with the same weight as the earlier Type 95, but with thicker armor. The prototype of the new Type 98 tank was completed by Hino Motors, but it did not enter production at the time. This can be attributed to the adequate performance of the aging Type 95 against obsolete tanks of National Revolutionary Army of the Republic of China forces.

With the start of World War II, the Imperial Japanese Army General Staff quickly realized that the Type 95 design was vulnerable to .50 caliber machine gun fire and attempted to develop a light tank with the same weight as the Type 95, but with thicker armor. A production contract for the Type 98 was awarded to Hino Motors. Serious production began in 1942. A total of 104 Type 98s are known to have been built: 1 in 1941, 24 in 1942 and 79 in 1943. By the end of the war, the Imperial Navy had priority on steel for warships and aircraft construction, leaving the Imperial Japanese Army at a low priority for raw material to build tanks.

Design

The design of the Type 98, in comparison to the Type 95, featured thicker, welded armor of improved shape, including the use of a Mitsubishi Type 100 6-Cylinder air-cooled diesel engine, rated at 130 horsepower, and located sideways to make maintenance easier. Slightly lighter and shorter than the original Type 95, it could travel at 50 km/h even with its thicker armor. Three pairs of bogies with six road-wheels connected to the chassis using bell cranks, which transferred any movement in the bogies into sideways motion that was absorbed by springs.

In contrast to the one-man turret of Type 95, the Type 98 had a two-man turret, which offered more room for the gunner/commander and carried a Type 100 37 mm tank gun, with a muzzle velocity of 760 m/s, and also a coaxial 7.7 mm machine gun.

Variants

Type 98B Ke-Ni Otsu (九八式軽戦車（乙型）, Kyuhachi-shiki keisensha (Otsu-gata))

A Mitsubishi-designed alternative to the standard model made by Hino. The most distinct feature was the suspension with four large road-wheels supported by side-ways facing coil springs, in a manner similar to Christie suspension. It was an experimental model, never accepted for production.

Type 2 Ke-To

An improvement of the Type 98A version, fitted with the more powerful Type 1 37 mm gun featuring a muzzle velocity of 800 m/s. The new 37 mm gun used gave the tank "slightly better performance". The Type 2 Ke-To went into production in 1944–1945 with 34 tanks built.

Type 98 Ta-Se 20 mm anti-aircraft tank

In November 1941, development began on an anti-aircraft version of the Type 98 with a 20 mm AA gun converted from a Type 98 20 mm autocannon in a circumferential turret. The single prototype was designated Type 98 Ta-Se, for Taikū ("anti-air") sensha ("tank"). There was also a prototype built with twin 20 mm AA guns also converted from the Type 98 20 mm autocannon. It was known as the Type 98 20 mm AAG Tank. During trials it was determined that the chassis was too small to be a stable "firing platform". Therefore, the project was canceled and neither tank was put into production.