Twilight 2000 Notes: In the Twilight 2000 timeline, the Type 61 remained in service in a home guard role, but none left the Japanese Islands. Other small upgrades, such as radios and ammunition storage, continued to be made throughout the Type 61’s career. Initially, the Type 61 had no night vision equipment or smoke grenade launchers, though IR vision for the gunner was added in the mid-1960s and improved in the early 1970s in the early 1960s, a large white light/IR searchlight was also mounted above the main gun, and four smoke grenade launchers were mounted on each side of the turret. The turret roof has commander’s and loader’s hatches the commander has a pintle mount in front of his hatch for a heavy machinegun. Layout is conventional with the driver on the front right of the hull with main gun ammunition to his left in a thinly-armored bin. From the start, the Japanese felt that a 90mm main gun would be sufficient, as combat ranges on the Japanese Islands would be short and in 1961, 90mm guns were still capable of taking on most tanks. The original design also called for a gasoline engine of rather low power, but this was quickly changed to a more powerful Mitsubishi 12HM21 WT-4 570-horsepower diesel engine.

Though the Japanese originally wanted the future Type 61 to weigh no more than 25 tons, it was quickly realized that such a light tank would have rather poor armor protection, and the weight limit was raised to 35 tons. The Type 61 uses cast and welded steel plate armor like most tanks of the period. The Type 61 can be mistaken for the US M-41 at first glance, though the two are not related. The Type 61 began production in 1961, was produced until 1975, and remained in service until 2000 some 560 were built, though production was at a slow but steady rate. Since the Japanese had a recurring problem of the crew positions of US-designed tanks being too large for their shorter-stature troops, the Japanese elected to design their own tank, which became the Type 61. At that time, the Japanese were given an option to buy the US-built M-46/M-47 Patton tank or develop their own tank. Notes: After World War 2, Japan was prohibited from manufacturing their own weapon designs until 1954.

Japanese modern light tanks