JCh-5

JCh-5
Early variants of the JCh-5.
Type	Main battle tank
Place of origin	Menghe
Service history
In service	1979-present
Used by	Azbekistan Menghe Ummayah
Wars	Ummayan Civil War Innominadan Crisis Innominadan Uprising Second Pan-Septentrion War
Production history
Designed	1975-1979
Manufacturer	Chikai Heavy Machine Building Plant Insŏng Machine Building Plant
Produced	1979-2007
No. built	8,593
Variants	JCh-5.5
Specifications (JCh-5D)
Weight	45.5 metric tonnes
Length	9.64 m (inc. gun and fuel tanks) 6.41 m hull only
Width	3.64 m
Height	2.07 m to turret roof
Crew	3 (driver, gunner, commander)
Armor	welded steel plate "Second-generation ERA" (Menghean classification)
Main armament	125mm L/45 smoothbore gun
Secondary armament	12.7mm HMG (commander) 7.62mm GPMG (co-axial)
Engine	KP-12 diesel 708 kW (950 hp)
Power/weight	21.1 hp/tonne
Suspension	torsion-bar
Ground clearance	38 cm
Operational range	600 km (internal fuel), 800km (with external tanks)
Speed	60 km/h (road)

The JCh-5 (formal designation: 5호 주력 전차 / 五號主力戰車, O-ho juryŏk jŏncha, "No.5 Main Battle Tank;" short designation 전차-5, Jŏncha-o) is a main battle tank introduced in the Democratic People's Republic of Menghe and inherited by the Socialist Republic of Menghe. Though based on the Kolodorian T-64, it was specially modified to satisfy Menghean reliability requirements, and later followed its own upgrade and development trajectory. With a three-man crew, a low profile, and a 125mm autoloading gun, it introduced many features that would be emulated by later Menghean main battle tanks such as the JCh-6 and JCh-8.

A total of 8,593 JCh-5 tanks of all variants were produced in Menghe between 1979 and 2007, making the JCh-5 second most widely-produced tank in Menghe after the JCh-4. Along with the JCh-4, it is still widely used by Menghean reservist units, though in active units it has been fully replaced by the JCh-6 and JCh-8. Most JCh-5s in Menghe have been upgraded with improved fire-control systems, reactive armour, and the ability to fire gun-launched anti-tank guided missiles, and some have been rebuilt into JCh-5.5 tanks.

Development

T-64 evaluation

After the outbreak of the Vinyan War in April 1975, the Democratic People's Republic of Menghe sent observers to its communist ally Kolodoria to study the fighting, and closely followed reports from the front lines. Early clashes in the first year appeared to verify Menghean commanders' concerns that the JCh-2 was an obsolete tank and the JCh-4 was an insufficiently radical improvement. Menghean observers were particularly impressed by the performance of Kolodorian units with T-64s, and inquired about the possibility of importing the latest model. Unwilling to divert production away from the front lines, where new tanks were urgently needed, the Kolodorian government shipped four T-64Bs to Menghe for evaluation and held out the possibility of a production license if the war did not promptly conclude.

Menghean crews tested and evaluated the tanks in late 1975, and identified a number of problems not present in the battlefield reports. In particular, they found the T-64's engine to be unreliable, a problem intensified by Menghean engineers who were unfamiliar with the opposed-piston design. This also resulted in concern about high production costs, particularly with Menghe facing production bottlenecks in optical equipment and electronics.

The Menghean Ministry of National Defense also recommended updating the tank based on combat reports from the Vinyan War. For example, the T-64's ZU-64 cupola allowed the commander to remotely control the machine gun from inside the vehicle, a feature that initially impressed Menghean designers. Actual combat experience in the Vinyan War, however, indicated that a closed mount was disadvantageous. From below armor, the commander has limited visibility at high angles, and a low chance of seeing incoming helicopters or attack aircraft. The below-armor anti-aircraft sight's narrow field of view also makes it difficult to properly lead a fast-moving target. In actual combat, tank commanders on both sides often entered battle standing or peering above the hatch to look for ATGM teams, which were also harder to spot through the periscopes. Aiming to the rear, while permitted by the 360-degree cupola ring, was impossible in practice because the commander could only sit facing forward in the cramped turret. Finally, both threats which the commander's HMG is meant to counter--namely, helicopters and ATGM teams--threaten the tank with an anti-tank guided missile, which poses the same threat to the commander whether his hatch is open or closed, and are beyond the range of small-arms fire.

JCh-5G

Four-view diagram of a G-model JCh-5, including a side-view cutaway and a view of the hull without the turret.

With Kolodorian approval, the DPRM began development on a customized variant better suited for Menghe's strategic needs. They lengthened the hull by half a meter and installed a V-12 diesel generating 660 hp. The engine was placed with the crankshaft running perpendicular to the vehicle's path of travel. Though less powerful than the T-64's 5TDF opposed-piston engine, the Menghean powerplant was easier to manufacture, more reliable, and more familiar to Menghean mechanics and engineers.

The design of the commander's cupola was also heavily revised, resulting in a layout similar to that of the Letnian T-74. The GCh-75 HMG is fixed to a separate race ring that runs around the outside of the cupola on a separate track. Normally, it is locked in position facing the rear. This allows the commander to independently rotate the cupola without having to also rotate the heavy and off-center machine gun. To use the machine gun, the commander opens the hatch, stands on his seat, faces the rear, and holds the HMG's manual controls. A toggle lever allows the commander to either traverse the HMG independently on its race ring while leaving the cupola fixed in place, or lock the two race rings together and traverse the HMG and cupola as a single unit. The former is better for small adjustments, and the latter for pivoting to the direction of a threat.

Due to export limitations, and due to Menghean MoND hesitancy about introducing complex weapon systems, the capability to fire anti-tank guided missiles from the gun was omitted. Accordingly, the laser guidance block on the right side of the T-64B turret was omitted as well. The T-64B's infrared laser rangefinder, however, is retained, replacing the optical stereoscopic rangefinder in the T-64A and the JCh-4. This gives the JCh-5 considerably better accuracy than other Menghean tanks in service at the time of its introduction.

A number of smaller changes were incorporated as well. The co-axial PKT machine gun was replaced by a GCh-77 chambered in the 7.5×54mm cartridge, for parts and ammunition commonality with other Menghean tanks. The dials, optics, controls, and other labels were replaced with Menghean-language versions. In all other respects, the resulting design was identical to the T-64B, retaining the base design's left-side infrared spotlight, its composite armor scheme, and its small roadwheels.

A prototype built to these specifications underwent mobility and shooting trials in 1978, and quickly met state approval from the Ministry of National Defense, which was impressed with their characteristics and under pressure to bring a modern MBT into service. It received the designation JCh-5G. Production began in 1979 at the Chikai Heavy Machine Building Plant in Jinjŏng.

JCh-5N

Four-view diagram of an N-model JCh-5. Compare with the JCh-6G above, and note the octagonal turret and its thicker frontal armor.

An improved variant, the JCh-5N, entered service early in 1985. It can be easily distinguished from the JCh-5G because of its more angular welded turret, which incorporates an entirely new composite armor scheme. The new scheme uses layered ceramic and steel plates, and is reportedly both more effective and easier to manufacture. It is also easier to maintain: the welded panels above the composite armor sections can be cut off at a forward depot or factory, allowing workers to remove the damaged composite plates and install new ones. Internally, the welded turret is slightly larger, allowing the installation of more radio equipment.

The hull glacis armor was revised as well, with three evenly spaced 15mm plates of high-hardness steel replacing the 105mm glass textolite insert in a void space of the same volume. For a very small increase in weight, this armor scheme offered somewhat increased performance against APFSDS ammunition and similar performance against shaped charges.

The JCh-5N also added compatibility with the YDCh-13 gun-launched anti-tank guided missile. The laser guidance unit is located on the right side of the turret, forward of the commander's HMG mount. This guidance unit must be removed in order to access the cover panels for the composite armor. The Ministry of National Defense had planned to improve the optics as well, but Ryŏ Ho-jun's decentralization of factory networks had caused problems along the supply chain, so the old optics were retained.

Despite the economic disruption, Menghe was able to open a second production line for the JCh-5N in 1984, the same year the new variant entered production at the Chikai plant. This new facility, the Insŏng Machine Building Plant, was located in southern Menghe, far from Dayashina, which posed the main threat to Menghe at the time.

JCh-5D

Introduced in 1991, the JCh-5D addresses many faults which Chikai's engineers identified in the early 1980s but were unable to fix. It features improved optics and fire-control, including a laser rangefinder, and an improved gun stabilization system. It still relies on active infrared illumination for night vision, but the IR receiver is more sensitive and can see illuminated targets out to 800 meters. Many of these components were imported initially, though over the 1990s Menghe steadily increased the share of domestic components.

Externally, the JCh-5D sported a full suite of explosive reactive armour. Menghean sources refer to the reactive armor used on the JCh-5D as "first-generation" ERA: produced in small brick-like blocks, it is effective against single-charge HEAT warheads, but not tandem HEAT warheads or kinetic energy penetrators.

A more powerful diesel engine with an output of 950 horsepower more than offset the added weight of the reactive armor, increasing the JCh-5's road speed and improving its offroad mobility. The new engine was also more reliable, partly due to greater access to imported parts and higher-quality machining equipment.

Although JCh-4 production stopped in the early 1990s, a victim of the military budget cuts early in Choe Sŭng-min's tenure, JCh-5 production at both tank factories continued, albeit at about half of its peak level. Despite pressuring the Army to accept force reductions as part of a plan to improve relations with Dayashina, Choe Sŭng-min personally advocated for continued production of the JCh-5, on the basis that it would maintain employment at both factories and preserve Menghean AFV design expertise. Choe had also commanded a division with JCh-5s during his military career, even leading them into Donggyŏng during the Decembrist Revolution, and had a favorable impression of the vehicle.

JCh-5R

JCh-5 variants introduced between 1988 and 2008, including a JCh-5R prototype without reactive armor to show the turret geometry.

Though it came last in the series, the JCh-5R was in many respects the most improved new-production variant of the JCh-5. It added an entirely passive night vision system based on infrared imaging, increasing the range of detection of enemy targets and eliminating the need for an active infrared spotlight which could give away the tank's location. The gunner and commander both received new dual-mode electro-optical units with variable magnification. Along with further improvements to the stabilizer and laser rangefinder and the addition of a 360-degree wind and temperature sensor, this brought the JCh-5R's accuracy up to modern levels.

Externally, the main change to the JCh-5R was the installation of what Menghean sources term "second-generation" ERA. This reactive armor uses larger plates set at a steeper angle, and is able to wear down, destabilize, and shatter kinetic energy penetrators, improving the JCh-5R's protection in tank-on-tank combat. Internally, the turret floor and its plating were altered to allow the loading of 125mm APFSDS ammunition with a longer kinetic energy penetrator, though not as long as the KEP used on the JCh-6 and its successors.

Overall description

The JCh-5 shares the internal layout of the T-64 before it, with the driver sitting in the front and center, the commander sitting on the right side of the turret, and the gunner sitting on the left side of the turret. The interior of the tank is cramped, but the smaller crew compensates for this somewhat. The 125mm main gun is fed from a carousel autoloader that sits under and around the turret crew, with the charges stored upright forming the walls of the turret basket. The autoloader holds 28 rounds and can reload the main gun at 8 rounds per minute, slower than a fresh human loader in a steady tank but faster than a tired loader or a loader in a moving tank. Up to 8 additional rounds, for a total of 36, can be stored around the interior of the hull, but this increases the already-high risk of explosion if the armor is penetrated.

A disadvantage of the carousel autoloader design is that the length of the projectile is limited because the entire round must be broken down into two pieces for storage. This was not a problem for early ammunition types, but it prevented the adoption of APFSDS penetrators beyond a certain length, limiting future growth in armor penetration capability. Subsequent Menghean main battle tanks, such as the JCh-6, addressed this by placing longer unitary ammunition in the turret bustle.

Full list of variants

Main battle tanks

The most recent combat variants of the JCh-5 main battle tank as of 2022.

• JCh-5G - Initial production model, manufactured between 1979 and 1983 exclusively at the Chikai Heavy Machine Building Plant. Of all JCh-5 variants, it most closely resembled the T-64B, though it lacked the latter's ATGM guidance capability and had a different machine gun cupola. It is the only JCh-6 variant with a cast turret.
  • JCh-5G1 - Refitted with smoke grenade launchers on the turret face.
  • JCh-5G2 - Refitted with "first-generation" ERA. It closely resembles the JCh-6D, especially with its turret masked by reactive armor. The most visible difference is that it has one fewer row of ERA bricks on either side of the turret face.
• JCh-5N - New production model introduced in 1984 at the Insŏng Machine Building Plant. It has a welded octagonal turret with a new composite armor scheme, though the two turrets are similar in approximate shape and layout. The JCh-6N also introduced the ability to fire the YDCh-13 GLATGM.
  • JCh-5N1 - Designation for JCh-5Ns fitted with the ERA blocks of the JCh-5D. The fire-control system was not upgraded.
  • JCh-5N2 - Designation for JCh-5Ns upgraded to JCh-5R standard. They are essentially identical to JCh-5D1s.
• JCh-5D - Production model introduced in 1991. It incorporates minor optics and stabilizer improvements compared to the JCh-6N, but retains the obsolete active infrared illumination system. It is also the first JCh-5 variant to carry reactive armor, with small blocks on the turret, hull sides, and glacis plate.
  • JCh-5D1 - Designation for JCh-5Ds modified to JCh-5R standard. The first-generation ERA blocks are replaced by second-generation ERA blocks, which can degrade the performance of APFSDS ammunition. The commander's front periscope was replaced with an electro-optical sight with visual and passive infrared modes, though the two-part cupola design was retained, and the commander cannot operate the 12.7mm heavy machine gun remotely. Upgrading the gunner's sight presented similar problems, as the JCh-5R's combined visual, infrared, and laser sight required a new turret roof design with a wider gap through the roof. Rather than thoroughly cutting and welding the existing turret roof armor, the designers installed a separate IR and laser guidance sight in place of the existing auxiliary gunner sight, and replaced the visual sight as well. The gunner thus has two different gunsights to choose from. Refitted JCh-5D1s first appeared in 2008.
• JCh-5R - New variant produced from 2002 to 2007. Features an entirely new gunner's sight and cupola, though the rest of the turret is identical to the base turret of the N and D variants. It also features "second-generation" explosive reactive armour with greater effectiveness against APFSDS ammunition.
  • JCh-5R1 - JCh-5R refitted with the Ulsae sofkill active protection system, comprised of an infrared missile approach and laser designation warning sensor that can automatically deploy smoke on the bearing to the threat or activate a traversing laser dazzler. These required the removal of some reactive armor modules from the roof. The JCh-5R1 was first seen in 2011, one year after the introduction of the Ulsae APS.
  • JCh-5R2 - JCh-5R refitted with the full Jŏgran-un active protection system, including active radar panels on the turret cheeks and hardkill countermeasure launchers on either side of the turret rear. To make room for the newly added systems, the smoke grenade launchers were rearranged, and the storage bins on the rear of the turret were replaced by a new, more rectangular group of bins, giving the tank a passing resemblance to the S.804 prototype vehicle. No under-armor changes were made apart from the installation of an interface box for the Jŏgran-un APS, however, and the large rectangular turret bustle is comprised entirely of external stowage bins and APS electronics, with no bustle autoloader or ammunition rack.

JCh-5.5

Main article: JCh-5.5

Four-view diagram of the S.815 prototype, which entered production as the JCh-5.5G. Note the radical turret redesign and the baseline JCh-5G hull.

JCh-5.5 is the designation for a major variant of the JCh-5 main battle tank with a secondary autoloader in the turret bustle to allow the loading of unitary main gun ammunition. This, in turn, allows the use of longer and heavier APFSDS projectiles with better penetration capability.

A single testbed vehicle with the prototype designation S.804 was assembled in 1996 to evaluate the feasibility of a new-build JCh-5 successor with a bustle autoloader in addition to the hull autoloader. The bustle autoloader was only armored against shrapnel and small-arms fire, and could only hold 14 rounds. Procurement staff from the Ministry of National Defense ultimately rejected this design in favor of the S.804, which had a new hull, a new engine, and a turret with better protection and increased ammunition capacity. The S.804 entered mass production, with minor changes, as the JCh-6.

Interest in a bustle-loading turret for the JCh-5 resurfaced in the late 2000s, motivated not by any requirement to introduce a new tank, but by an interest in upgrading the thousands of JCh-5 tanks already in service with the Menghean Army. In 2012 Chikai unveiled the S.815 prototype, which, compared to the S.804 of 1996, featured a new turret with better composite armor on the face and thicker armor on the sides of the turret bustle. The Ministry of National Defense approved it for mass production in 2013, with the first deliveries taking place in 2014. Because it is a rebuild kit for existing JCh-5 hulls, but replaces enough components to be functionally equivalent to a new tank model, the new vehicle was given the designation JCh-5.5, representing the midway point between the JCh-5 and the JCh-6, whose capabilities it adds.

All JCh-5.5 tanks are assembled at the Insŏng Machine Building Plant. Changes to the original design include the removal and replacement of the turret, the removal and replacement of the engine with a new powerpack, the installation of applique glacis plate armor, and the installation of heavier side skirts.

Production

Variant	Chikai	Insŏng	Total
JCh-5G	920 units	0 units	920 units
JCh-5N	1,659 units	742 units	2,401 units
JCh-5D	2,023 units	1,465 units	3,588 units
JCh-5R	1,539 units	245 units	1,784 units
All types	6,141 units	2,452 units	8,593 units

The JCh-5 was manufactured at the Chikai Heavy Machine Building Plant in Jinjŏng between 1979 and 2007, and at the Insŏng Machine Building Plant in Insŏng between 1984 and 2004. Nearly 8,600 units were produced in total during this time, making it (as of 2022) third most widely produced main battle tank to come out of Menghe, with the JCh-6 taking first place and the JCh-4 taking second. It was, however, in continuous production for 28 years, longer than any other postwar Menghean main battle tank.

The table on the right summarizes official production figures for the JCh-5. It includes both JCh-5s built for domestic Menghean service and JCh-5s built for export to other countries. It does not include specialty vehicles, such as armored recovery vehicles, manufactured using the JCh-5 hull, and it does not include one-off experimental vehicles like the single JCh-5D hull pulled from the production lines to produce the S.804 prototype.

Of the 920 JCh-5G units produced, 186 were exported to Uskonmaa and the remaining 734 were used by the Menghean Army. Of these, at least 12 and possibly more were lost during Menghe's intervention in the Polvokian Civil War. According to separate production data, 703 JCh-5G hulls were used in JCh-5.5G conversions; the remaining 19 hulls were sold to museums, lost in accidents, or used for target practice.

Operators

Owing to its late introduction in 1979, its relatively modest features, and the global embargo against Menghe in 1984-1988, the JCh-5 was not exported very widely. Many Namhae Front members, including close allies like Polvokia, use the T-74 instead. This includes Argentstan and the Republic of Innominada, which inherited large T-74 stocks from surrendering, routing, or defecting Innominadan People's Army units after the Innominadan Crisis.

Current operators

• Template:Country data Azbekistan: 810 units, all new-build JCh-5D variants, delivered between 1994 and 1998.
• Menghe: 4,388 units, excluding hulls used for JCh-5.5 conversions. By 2015, all JCh-5G models had been retired from service, either repurposed into JCh-5.5G conversions or sold to parks and museums. The remaining JCh-5 models, most of which have been upgraded to R2 standard, were in reserve service before the start of the Second Pan-Septentrion War.
• Template:Country data Ummayah: 820 units, a mix of secondhand Menghean N and D variants, exported between 2005 and 2008 as part of a program to build up Ummayah's newly-created armed forces.

Former operators

• Template:Country data Uskonmaa: 402 units, of which 186 are new-build JCh-5Gs delivered in 1982-1984 and 225 are JCh-5D units delivered in 1992-1994. The original shipment was interrupted by the global trade embargo imposed as a response to Menghe's nuclear weapons program. Between 2014 and 2019, all of Uskonmaa's operational JCh-5 tanks were rebuilt into JCh-5.5 tanks.