Japanese tank engineering always lacked behind the Allies during World War 2 (1939-1945) and only a few notable designs emerged from the fighting. As with other world powers of the time, the nation also invested, although a little too late, in the concept of the dedicated tank destroyer. One example of this became the Type 1 "Ho-Ni" which appeared in two other related battlefield forms, the Type 1 "Ho-Ni II" and the Type 3 "Ho-Ni III". It was built atop the existing running gear and chassis of the Type 97 Chi-Ha Medium Tank.
The Type 97 emerged in 1938 prior to the war and, by classification, was a medium tank. However, compared to its contemporaries, it held qualities more closely associated with the light tank concept. At its introduction, the Type 97 did prove on par with Western offerings but, by 1942, it was severely outclassed though production was allowed to continue for lack of anything better.
To extend the usefulness of the Type 97 chassis as well as fulfill a Japanese Army need for a tank destroyer, engineers reclaimed the powerpack and chassis of the medium tank and removed the turret structure. In the turret's place was installed a 75mm Type 90 field gun in a fixed, open-air structure (only the front and sides of the enclosure were protected from the elements and battlefield dangers). A fixed superstructure saved on weight and provided the necessary workspace for the gunnery crew but restricted traversal and elevation of the gun unit. In essence the entire tank would have to be turned towards the intended field of fire. Fifty-four 75mm projectiles were carried aboard and the operating crew numbered five. Beyond the main gun there was now defensive armament fitted save anything personal carried by the crew.
The result design became the Type Ho-Ni I which appeared in limited numbers during 1942.
The 15.4 ton vehicle showcased a length of 5.9 meters, a width of 2.3 meters and a height of 2.4 meters - it held a relatively tall profile. Armor protection ranged from 25mm to 51mm and power was served through a Mitsubishi SA12200VD series V12 air-cooled diesel engine which propelled the vehicle to speeds of 24 miles per hour and ranges out to 120 miles. The hull sat atop a bell-crank suspension system.
The Type 1 Ho-Ni was used operational for the first time in the Battle of Luzon (Philippines Campaign) during early/mid-1944. Organized forces lacked the numbers to affect the outcome of the battle positively and results of the vehicles themselves were mixed. Only twenty-six first-series vehicles were produced.
The Type 1 Ho-Ni II was another Type 97 tank development but this vehicle emerged more as a self-propelled gun platform fitting the 105mm Type 91 howitzer instead of tank-killing armament. This was set within a slightly revised armored superstructure and intended as a fire support vehicle.
A more closely related development of the Type 1 Ho-Ni I became the Type 3 Ho-Ni III which now fitted the more-powerful 75mm Type 3 anti-tank gun in a fully-enclosed armored hull superstructure to protect the gunnery crew.
With its lackluster field performance, the vehicles were retained for homeland defense before the end of the war which came in August of 1945. Total production numbered just 111 of these make-shift gun carriers.