Type 74

Type 74
Type - Main battle tank
Place of origin - Japan
Service history
In service - 1975-present
Production history
Designer - Mitsubishi Heavy Industries
Designed - 1962
Manufacturer - Mitsubishi Heavy Industries
Unit cost - 350-400 Million Yen (~3.2 - 3.6 Million USD)
Produced - 1975-1988
No. built - 873
Specifications
Mass - 38 tonnes (42 short tons; 37 long tons)
Length - 9.41 m (30 ft 10 in)
Width - 3.18 m (10 ft 5 in)
Height - 2.25 m (7 ft 5 in)
Crew - 4
Armor - 189-195 mm (7.4-7.7 in)
Main armament - 105 mm L7A3 rifled gun (55 rounds)
Secondary armament - M2HB 12.7 mm machine gun (660 rounds) / Type 74 7.62 mm machine gun (4,500 rounds)
Engine - Mitsubishi 10ZF Model 21, 10 cylinders diesel, 21.5 L . 750 hp (560 kW)
Power/weight - 19 hp/tonne
Suspension - hydropneumatic
Operational range - 300 km (190 mi)
Maximum speed - 53 km/h (33 mph)

The Type 74 (74式戦車, nana-yon-shiki-sensha) is a main battle tank (MBT) of the Japan Ground Self-Defense Force (JGSDF). It was built by Mitsubishi Heavy Industries as a supplement to 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 Patton or German Leopard 1. Like these designs, it mounts the Royal Ordnance L7 rifled 105 mm gun. The design did not enter widespread use until 1980, by which point other Western forces had introduced more capable designs.
It was followed by the heavier Type 90. Both the Type 74 and Type 90 are supplemented and will be eventually replaced by the new-generation Type 10 tank.
History
The JGSDF began studies on new tank designs with Mitsubishi in 1962, after the Type 61 had been shown to be outmatched by new Soviet tanks such as 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 a similar 105 mm 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 (first prototype) were already in development independently in Japan. The design was finalized in 1964 and various test rigs were built between 1964 and 1967.

Design

Armament
The first vessels had been designed to bear the 90 mm M3 cannon, present in the Type 61, and ST-A1, revealing itself underpowered. Later in the development stage engineers opted to license the NATO standard Royal Ordnance L7 105 mm cannon. Japan only produced the barrel under license, developing an indigenous mantlet, breech and recoil system. The full length of the cannon was 5,592 mm, for a total weight of 2,800 kg. Initially, the main gun only used APDS (Armour-Piercing Discarding Sabot) and HEP (High Explosive Plastic) as its primary ammunition. Later it was modified to fire APFSDS (Armour-Piercing Fin-Stabilized Discarding Sabot) and HEAT-MP (High-Explosive Anti-Tank Multi-Purpose) shells as well.
The secondary armament consisted of a 12.7 mm anti-aircraft machine gun (with 660 rounds) and a 7.62 co-axial machine gun (4500 rounds).
Mobility
The Type 74 tank is powered by 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; however, speeds of at least 60 km/h have been achieved.
Armor
Instead of composite armour (as used on the later Type 90 main battle tank), the Type 74 adopted welded steel plates for hull construction, with sloped armour extensively used to defeat armour-piercing shells and other kinetic energy penetrators. It has frontal hull armor of 80 mm with an effective armor thickness of up to 189 mm for the upper glacis and 139 mm for lower glacis. Side armor is 35 mm, while rear armor is 25 mm thick. The cast steel turret has an estimated 195 mm of armor. When compared to other second-generation MBTs, the Type 74 has more armour than a Leopard 1 (122 mm and 140 mm), but less than comparable Soviet vehicles such as the T-62 (174 mm and 204 mm).
Service
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, as was the remote-controlled anti-aircraft machine gun. The overall 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 rather than 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 considered outdated even before it entered service. The Type 90 was to have replaced it outright, but with the end of the Cold War, these plans were scaled back. In 1993 four Type 74s were improved to the new Type 74 Kai (改) [Type 74 mod G (G型)] standard, adding a passive infrared camera and side skirts. The upgrade proved to be extremely expensive, and the program was abandoned.
Starting in April 2019, the Ministry of Defense enacted the Medium-Term Development Defense Plan (31中期防), which involved the retirement of Type 74 main battle tanks in service, to be replaced by the newer Type 16 Maneuver Combat Vehicle.
At the same time, official tank units based on the main land of Honshu, Kyushu, and Shikoku would be disbanded and replaced by new mobility-based combat units, in the form of a Rapid Deployment Regiment or Reconnaissance Combat Battalion, with the Infantry-based Divisions and Brigades to feature one of either. For each of the new units, they are to be equipped with a unit of Type 16 MCVs (1-2 Companies).
Despite the plan being official as of 2019, the first tank units were disbanded throughout 2018, including the 4th Tank Battalion (4th Division), 8th Tank Battalion (8th Division), and 14th Tank Troop (14th Brigade). After the plan's enactment, 6th Tank Battalion of the 6th Division North Eastern Army was disbanded, and changes were made to existing tank formations, including at JGSDF Fuji School, to phase out numbers of Type 74 tanks in service. As of March 17, 2022, the disbandment of the 1st Division's 1st Tank Battalion of the Eastern Army has been the most recent change to the armored formation of the JGSDF.
Variants
Type 74 first mod (74式戦車 初期生産型)
Type 74 mod B (74式戦車 B型)
Type 74 mod C (74式戦車 C型)
Type 74 mod D (74式戦車 D型)
Type 74 mod E (74式戦車 E型)
Type 74 mod F (74式戦車 F型)
Type 74 mod G/Kai (74式戦車 G型/改)
Type 87 Self-Propelled Anti-Aircraft Gun (87式自走高射機関砲)
Type 78 Armoured recovery vehicle (78式戦車回収車)
Type 91 Armoured vehicle-launched bridge (91式戦車橋)
Operators
 Japan - 893 produced between September 1975 and 1989, with 225 delivered by January 1980. 822 in service in 1990, 870 in service in 1995 and 2000, 700 in service in 2006. As of March 17, 2022, from the disbandment of the 1st Division's 1st Tank Battalion of the Eastern Army, approximately 130 Type 74 tanks remain in service today.
Japan Ground Self-Defense Force
JGSDF Northern Army.svg Northern Army
JGSDF 2nd Division.svg 2nd Division
2nd Tank Regiment (1st, 2nd, 3rd, and 5th Tank Squadron)
North Eastern Army
9th Division
9th Tank Battalion (1st and 2nd Tank Company)
Central Army
3rd Division
3rd Tank Battalion (1st and 2nd Tank Company)
JGSDF 10th Division.svg 10th Division
10th Tank Battalion (1st and 2nd Tank Company)
13th Brigade
13th Tank Troop
JGSDF Fuji School
JGSDF Fuji School (Combined Training) Brigade
Armored Guidance Corps (4th Company)

Type 61
Type 90
Type 10