Type 74 MBT

The Type 74 is a main battle tank (MBT) of the Japan Ground Self-Defense Force (JGSDF). It was built by Mitsubishi Heavy Industries as a replacement for the earlier Type 61. It was based on the best features of a number of contemporary designs, placing it in the same class as the US M60 or German Leopard 1. Like these designs, it mounts the Royal Ordnance L7 105 mm gun. The design did not enter widespread use until 1980, by which point other western forces were starting the introduction of much more capable designs.


Type 74 MBT
Class Vehicle
Type Armoured Fighting Vehicle
Manufacturer Mitsubishi Heavy Industries
Production Period 1975 - 1988
Origin Japan
Country Name Origin Year
Japan 1973
Country Name Operational Year Retirement Year
Japan 1975 View
ManufacturerName Production From Production To Quantity
Mitsubishi Heavy Industries 1975 1988 850 View

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 US-German MBT-70 project, the hull of the Leopard 1, and the L7 105mm gun. The design included a rotating cupola for the commander, and a new autoloader for the main gun. Prior to the 1965 decision to design an entirely new tank, some technologies which would later be used in the STB-1 were already in development independently in Japan.The design was finalized in 1964 and various test rigs were built between 1964 and 1967.

Armament

During the development stage, engineers opted for a license on the NATO standard Royal Ordnance 105mm cannon. The part that Japan imported for license production was only the barrel. Breech, recoil system and mantlet around the cannon were later built in Japan. The full length of the cannon, including all parts just mentioned, was 5,592mm long and the total weight was 2,800kg. Initially the main gun only used APDS (Armor-Piercing Discarding Sabot) and HEP (High Explosive Plastic) as its primary ammunition. Later it was modified to fire APFSDS (Armor-Piercing Fin-Stabilized Discarding Sabot) and HEAT-MP (High-Explosive Anti-Tank Multi-Purpose) shells as well.

Secondary armament consisted of a 12.7mm anti-aircraft machine gun (660 bullets carried) and a 7.62 co-axial machine gun(4500 bullets carried).

Mobility

The Type 74 tank has the Mitsubishi 10ZF Model 21 10-cylinder two-stroke cycle diesel engine providing 750 hp (560 kW). At 19 hp/tonne, its power-to-weight ratio is similar to the French AMX-30. The maximum quoted road speed of the Type 74 is 53 km/h but its top speed is at least 60 km/h.

Armor

Type 74 adopts welded bulletproof steel plates instead of composite armor which is later used on Type 90 main battle tank. However, sloped armor is extensively used to defeat armor-piercing shells and other kinetic energy penetrators. Type 74 has a frontal hull armor of 80 mm. Due to its heavily sloped nature, its effective armor thickness goes up to 189 mm for upper glacis and 139 mm for lower glacis. The side armor of Type 74 is 35 mm thick while the armor at the back is 25 mm thick. The frontal armor of the cast steel turret has been estimated to be 195 mm. When compare Type 74 with other second generation main tanks, its armor is worse than T-62(174mm and 204mm) but better than leopard 1. (122mm and 140mm) 

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 standard, adding a passive infrared camera, side skirts, and so on. The upgrade proved to be extremely expensive, and the program was dropped.

GENERAL INFORMATION
DesignationsType 74
Manufacturer(s)Mitsubishi
StatusProduction completed. In service with Japan.
Production Period1973- circa 1988Production Quantityabout 850
TypeMBTCrew4
Length, overall9.4mLength, hull6.7m
Width, overall3.2mHeight, overall2.7m
Combat Weight38000kgUnloaded Weight36000kg
Radio, externaln/aCommunication, crewn/a
FIREPOWER
Main Armament105mm rifled gun (1)Ammunition Carried55x105mm
Gun Traverse360Elevation/Depression+10/-7 (2)
Traverse Raten/aElevation Raten/a
Gun Stabilizationvertical/horizontalRangefinderlaser
Night VisionyesAuto-Loaderno
Secondary Armament7.62mm MG (coaxial)
12.7mm MG (AA)
Ammunition Carried4500x7.62mm
660x12.7mm


MOBILITY CHARACTERISTICS
EngineMitsubishi 10ZF Type 22 WT 10-cylinder air-cooled dieselTransmissionMitsubishi MT75A manual (6 forward, 1 reverse)
Horsepower750hp at 2200rpmSuspensionhydropneumatic
Power/Weight Ratio19.7hp/tTrack Width550mm
Speed, on road53km/hTrack Ground Contact4m
Fuel Capacity950 lGround Pressure0.85kg/cm2
Range, on road300kmGradient60%
Fuel Consumptionn/aVertical Obstacle1.0m
Turning Radiusn/aTrench Crossing2.7m
Ground Clearance0.2-0.65mFording1.0m (3)
SURVIVABILITY FEATURES
Smoke Laying2 x 3 smoke dischargersNBC Protectionyes
Armor DetailsAll-welded steel hull. All cast turret.
TECHNICAL DRAWINGS AND OTHER IMAGES
NOTES
(1) A licenced copy of the British Royal Ordnance L7 series tank gun. (2) Using suspension allows elevation/depression of main armament to increase to +15/-13. (3) Fording depth 2m with preparation.
REFERENCES
JMBT

End notes