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. Features from several designs were incorporated, including the controllable suspension of the MBT-70, the rolled steel hull of the Leopard 1, and the L7 105mm gun. Features unique to the design included a rotating cupola for the commander, and a new autoloader for the main gun. The design was finalized in 1964 and various test rigs were built between 1964 and 1967.
The first prototype, designated STB-1, was delivered in late 1968 and underwent a number of modifications until 1969. The autoloader proved too complex and expensive, and was removed, additionally the remote controlled anti-aircraft machine gun was removed. The design of the turret was also changed, becoming longer. These changes resulted in the STB-3, which was delivered in 1971. 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.
In service, the tanks were updated with the addition of infra-red imagers (not image intensifiers) for the commander and gunner, and a laser rangefinder in the commander's cupola. 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.
The Type 74 was generally outdated even before it entered service. The Type 90 was to have replaced it outright, but with the ending of the Cold War these plans were scaled back. In 1993 four Type 74's were improved to the new Type 74 Kai [Type 74 mod G] standard, adding a passive infrared camera, side skirts, and so on. The upgrade proved to be extremely expensive, and the program was dropped.
| Type 74 | |
|---|---|
| Type | Main battle tank |
| Place of origin |  Japan |
| Service history | |
| In service | 1975 to present |
| Production history | |
| Designer | Mitsubishi Heavy Industries |
| Designed | 1962 |
| Manufacturer | Mitsubishi Heavy Industries |
| Produced | 1975 - 1988 |
| Specifications | |
| Weight | 38 tonnes |
| Length | 9.41 m |
| Width | 3.18 m |
| Height | 2.25 m |
| Crew | 4 |
| | |
| Armor | 120 mm |
| Main armament | Royal Ordnance L7 105 mm rifled gun 55 rounds |
| Secondary armament | M2HB 12.7-mm machinegun 660 rounds Type 74 7.62-mm machinegun 4,500 rounds |
| Engine | Mitsubishi 10ZF Model 21, 10 Cylinders Diesel, 21500cc 750 hp (560 kW) |
| Power/weight | 19 hp/tonne |
| Suspension | hydropneumatic |
| Operational range | 300 km |
| Speed | 53 km/h |
