Sh99 Heavy Tank

Sh99 Heavy Tank - The Federation of Ekraysia



Statistics


Class: Heavy Tank

Dimensions
Weight, Combat: 97,750kg
Length, Hull: 7.84m
Length, Gun Forward: 13.63m
Width: 5.80m
Height: 3.09m

Armament
Main Armament: 1x Sh91HV 170mm/52.5 High Pressure ETC Smoothbore, 27 Rounds
Secondary Armament: 1x Sh92R 57mm ETC Automatic Cannon, 210 Rounds
Tertiary Armament: 2x Sh94 7.7mm GPMG, 10500 Rounds
- 32x Anteck Multipurpose Grenade Launchers

Engines
Main Engine: Axon 63.0 litre V16 Multifuel, 2700hp at 2900rpm
APU: 2x MYS Straight-3 Multifuel, 37hp at 4560rpm

Protection
Composite, Steltexolite, ERA, NERA, Slat Armour
- ORDEN Fighting Vehicle Countermeasures System

Performance
Top Speed: 40.15mph (64.62kph)
Top Speed, Cross-Country: 26.20mph (42.16kph)
Acceleration, 0-20mph (0-32kph): 6.9 seconds
Road Range: 360miles (580km)


History


Although the Sh92 Main Battle Tank was serving the Ekraysian armed forces rather well, it was being realised as early as in the vehicle's prototype stage that, out of it's native tropical and jungle environment, it was outclassed, not in terms of the design itself, but of size. Many newer Main Battle Tanks were of seventy to eighty-five tonnes total weight and armed with 140mm Electrothermal-Chemical Technology main guns, as well as large coaxial autocannon. Therein lay a problem; should Sh92s need to confront these vehicles, while it may be able to match them in terms of firepower - with an overpressure, high-velocity 130mm ETC gun and 37mm coaxial automatic cannon - it could not match them in weight of armour. Thusly, it could only have an advantage over these heavier, more unwieldy but better-armoured and armed in it's home environment, something which would likely not exist abroad, in the vast, lush plains of the temperate climates of many other nations. It was here that the Sh92 would ultimately be outclassed at some point, and so it was decided to build a tank to supplement the Sh92 in these conditions.

Clearly, a vehicle merely equivalent to this potential opposition would be a waste of time; design parameters would be too close to the Sh92 to efficiently produce both, and so it was decided to make an altogether heavier tank which could destroy possible opposition at longer range than they could destroy it, the theory being that since enemy tanks would need to close to uncomfortably close range to knock this heavy tank out, they would become rapidly vulnerable to the fire from the supported Sh92s. A vehicle for this job would have to be not too extravagant, so as to allow mass production to support Sh92s a viable option, but nevertheless, protection from it's own main gun, and larger, was envisaged over the frontal arc and proof against 140mm ETC fire was decided upon for the sides, with 120mm ETC protection over the rear quarter. The project, standardised as the Sh99 and entering service in pre-production form (these vehicles have since been upgraded) in late 1998, was set in design stage in September 1994 under the MYS/Axon defence agreement. Prototypes were ready by mid-1997 and the eventual goal is to have these vehicles (on foreign deployment missions) available to support Sh92s on a ratio of two to seven; there is a slight shortfall but it is calculated that all armoured regiments will be up to full strength by early 2010.

It should be made expressly clear at this point, once again, of the role of the Sh99; it is a support tank and assault gun, designed for the destruction of enemy tank formations from beyond their reach, and also in breakthrough operations in the same circumstances. It is not a main battle tank and is not capable of such general-purpose operations in its own right. As employed and designed, it requires substantial support from both infantry and lesser main battle tanks to function to it's full ability. It can be considered an equivalent to the LY6 series (including the -A1). It has not yet seen combat, but those armoured regiments slated for rapid-deployment duties, or slated for overseas deployment to secure other areas in Gholgoth in the event of hostilities against the region, have full complements of combat-ready Sh99s.

The vehicle has some deployment difficulties; it simply cannot be taken by standard-gauge railways due to both its size and mass, and can only deploy on solid terrain, despite a slightly superior ground pressure figure to the Sh92. The only ships with a proven capacity to carry the vehicle are the current generation of Ekraysian amphibious operations and landing vessels, although several other foreign naval types can also, in theory, carry the Sh99. Like the Sh92, the Sh99 has a reputation for being a little crude and somewhat overbuilt. This makes the vehicle quite reliable but also not as sophisticated, perhaps, as some of its contemporaries.


Armour


Armour would have to be heavier than the Sh92s, for sure, to be able to defeat the projectiles which would be hurled against it. Unlike many, indeed, most modern tanks, the vehicle employs highly sloped side armour, sloped at the front to as much as 80 degrees, and on the sides to about, 30 degrees. While the extra width this required would be quite large, it was decided to utilise larger tracks to take advantage of this and otherwise focus on the fact that the vehicle is not exceptionally maneuvrable anyway. Similar armour is used as much as possible over the turret. It has higher-sloped armour, and more of it, than many of it's contemporaries such as the LY6, LY6A1, MCA-7A to G and TD-7.

The baseline layers consist of mainly composite armour with a thick layer of IRHA (see below), a 122mm (4.8in) gap filled with rubber, a layer of TiB2, and another layer of IRHA, of about two-thirds of the thickness. The armour has significant naval influence, the purpose of the cushioning material such as rubber and the outer IRHA layer meaning not to stop a round but deplete it's kinetic energy so that it will be defeated by the heavier but overall slightly thinner layers (collectively) beneath it, the construction but not the purpose similar to NERA, or Non-Explosive, Reactive Armour. Behind these are a thicker layer of TiB2, and behind that a very slightly thinner Improved Rolled Homogeneous Armour layer, known as IRHA, sandwiching the TiB2. The second main layer is almost as thick, and of solid titanium and Depleted Uranium mesh, the latter arranged in a non-uniform pattern so as to prevent fragmentation or spall from simply avoiding the armouring altogether. Then there is a layer of balls Boron Carbide, B4C, set into Depleted Uranium and IRHA. Boron Carbide is a material slightly superior to TiB2 but with inferior performance against larger-calibre hits. This layer is placed as far back to block any last shards of penetrating material that may. Behind this third layer is a thinner spall liner of steltexolite, a material superior to Kevlar providing insulation for noise.

Over the frontal arc, the armour is sloped at up to eighty degrees, ten from horizontal, and the lower frontal underside hull armour, traditionally even weaker than the rear armour, has been strengthened in retrofit packages to the standards of the side armour, giving the driver total protection and overall increased survivrability against mines. Strengthening of this armour was crucial, as noted from a particular incident with a British Challenger 2;
'August 2006 - the driver of a Challenger 2, Trooper Sean Chance, lost three of his toes when an RPG-29 bounced off the road, and penetrated the lower frontal hull armour (traditionally the weakest place on a tank) during an engagement in al-Amarah, Iraq'.

Mineclearing variants of the Sh92 MBT are best used to combat mines, but the vehicle employs some of the latest thinking available in order to combat mines without sacrificing the vehicle's effectiveness. Suspended seating, armoured from below, is standard and the underside of the hull mantains a 21-degree V in order to deflect the blast from mines. The underside of the hull is also armoured to a degree that is not overall very heavy, but makes use of spaced armour, TiB2, and IRHA. Similar armouring, designed to deplete a charge kinetically, adorn the hull, although the vehicle and turret roof rely heavily on this form of armour.

On the matter of add-on armour, however, there was equal interest. By doctrine, such armour was not classed as standard, however, even at the most basic level they were retrofitted widely in workshops, and so much provision was made for them.
Ekraysian forces had made much use of NERA, or Non-Explosive Reactive Armour, essentially an ERA brick with the explosives taken out, and replaced with a filling such as rubber. Two metal plates sandwich an inert liner, such as rubber. When struck by a shaped charge's metal jet, some of the impact energy is dissipated into the inert liner layer, and the resulting high pressure causes the inert layers of rubber to condense and then expand, causing the plate to move forward. As the plates bulge, the point of jet impact shifts with the plate bulging, increasing the effective thickness of the armour. This is almost the same mechanism as the second mechanism that explosive reactive armour uses, but it uses energy from the shaped charge jet rather than an explosive. Since the inner liner is not explosive itself, the bulging is less energetic than on explosive reactive armour, and thus offers less protection than a similarly-sized ERA. However, NERA and NxRA are lighter and completely safe to handle (and safe for nearby infantry), can theoretically be placed on any part of the vehicle, and can be packaged in multiple spaced-out layers if necessary. A key advantage of this kind of reactive armour is that it cannot be defeated via tandem warhead shaped charges, which employ a small forward warhead to detonate ERA before the main warhead fires.

Like in the Merkava, diesel fuel is stored in the side spaces in between the spaced armour, providing integral fender tanks and extra stopping power against HEAT rounds. However, as the engine is a multifuel and not all possible engine fuels for the Sh99 are as safe as diesel, technical knowledge of them [the fuels] and caution are advised, as the vehicle can also mount a jettisonable twin rear fuel barrel mount, the fuel barrels of which are typically removed prior to combat.

In times of higher risk, however, standard ERA reigns supreme and is becoming more widespread. In improved copy of Kontakt-5 with a narrower engagement area, as used by the Russians and Ukrainians, is standard ERA and is made up of ‘bricks’ of explosive sandwiched between two metal plates. The plates are arranged in such a way as to move sideways rapidly when the explosive detonates. This will force an incoming KE (Kinetic Energy) penetrator or shaped charge jet to cut through more armour than the thickness of the plating itself, since "new" plating is constantly fed into the penetrating body. A KE penetrator will also be subjected to powerful sideways forces, which might be large enough to cut the rod into two or more pieces. This will significantly reduce the penetrating capabilities of the penetrator, since the penetrating force will be dissipated over a larger volume of armour. The effectiveness of Kontakt-5 ERA was confirmed by tests run by the German Bundeswehr and the US Army. The Germans tested the K-5, mounted on older T-72 tanks, and in the US, Jane's IDR's Pentagon correspondent Leland Ness confirmed that "When fitted to T-72 tanks, the 'heavy' ERA made them immune to the DU penetrators of M829 APFSDS, fired by the 120 mm guns of the US M1 Abrams tanks, which were among the most formidable tank gun projectiles at the time." This is of course, provided that the round strikes the ERA, which only covers 60% of the frontal aspect of the T-72 series tank mounted with it.
Another simpler but equally worthwhile addition is slat armour, bars of metal arranged in such a way so as to form a ‘cage’ around the tank to prematurely detonate incoming RPGs (Rocket-Propelled Grenades) or other anti-armour High-Explosive Anti-Tank – HEAT - warheads with contact or close proximity detonation fusing. The turret standard ‘carry-basket’, fitted around the sides and rear of the turret for attachments or carrying smaller objects, and also worthy as a handgrip, can often be found with some sort of continuation of itself upwards towards the turret roof, sometimes with some kind of mesh stretched around it.

All armour modules and subsections of these are designed to be easily removed and replaced individually, allowing rapid repair of battle damage, appropriate parts provided for.

The Sh99's unbroken glacis plate armour is designed to withstand 180mm APFSDS rounds at all ranges over three hundred and fifty metres and it's own main armament at four hundred to four hundred and fifty. The side armour protects from 140mm ETC to a hundred and fifty metres and the rear armour against 120mm ETC to a similar range. At a distance, the Sh99 is impervious to most rounds thrown at it.


Armament

Like the Sh92, the main gun was to have Electrothermal-Chemical (Hereon referred to as ETC) technology. The technology, an upgrade to Electrothermal technology and higher-powered than universally-applicable ETI, or Electrothermal Ignition, had numerous advantages and alternate means of increasing projectile velocity, as trials of coilguns and railguns had proved their non-viability in a MBT-sized platform. While this document shall not go into great detail about ETC technology, it should be noted what a promising step it is and the advantages it brings to tank firepower, allowing higher muzzle energy and the usage of heavier rounds.

It was decided to modify the Sh91 main gun, an ETC technology, 170mm, 52.5-calibre rifled gun as used on the Sh93 self-propelled gun, extensively from a gun-howitzer to a high-velocity anti-tank gun, with the new designation Sh91HV, or High-Velocity. A completely new barrel, with larger fume extractor located nearer the end of the barrel, was designed in smoothbore rather than rifled configuration and the breech heavily reinforced for use with higher-pressure, higher-velocity ammunition. It is a solid-propellant gun using Plasma Jet ignition, often fitted with a thermal sleeve, of stess-hardened construction, with a fluted, chromed breech and barrel. It is an exceptionally high-pressure and high-velocity weapon with an average at best barrel life despite a heavily overbuilt construction.

It uses solid propellant over the growing excitement about liquid propellant for three good reasons. (1), liquid propellant can be seen as less stable due to it's liquid nature, (2), it is thus less user-friendly, and (3) it is often less accurate as it is less stable, and can often give a weapon a 'wandering zero' issue.

The gun uses LOVA technology in it's propellant, which is explained here in a paper published by designers from Macabees before the design of the Nakil:

The weapon's 52.5-calibre barrel makes the gun's barrel 8.925 metres long, quite a way above the 7-metre maximum reccomended by tank designers, but it should be noted that the Sh99 is not expressly designed to fire on the move at speed. The gun cradle is of suitable size for a 140mm to 210mm weapon, although the turret and turret systems are not designed around the latter and will likely suffer from recoil and stress issues without adaptation. The main gun incorporates an elevation arc of -7˚ to + 35˚.

Equipped with a Karmen Defence vertical-carousel autoloader to reduce the crew to three, it is capable of 6-8rpm depending on ammunition although is typically used with a slower, more stable Rate of Fire. It cannot reload at higher angles. The gun can fire ammunition of many types, most potently DU (Depleted Uranium) – tipped rounds and guided AT missiles, of the Miera III type. It was decided not to fit them outside due to their relative vulnerability, and the fact that their role of sole antitank use was not enough to offset the risk. The autoloader can be hydraulically swung back and the carousels of ammunition disengaged for manual loading in seconds.
The Miera III is a high-speed AT/low-altitude Anti-Helicopter guided missile, top-attack in the case of the former, with a Beyond Visual Range capability and a primary and secondary tandem means of guidance, and with a range of 13.7 kilometres.

The autoloader, an enlarged variant of that fitted on the Sh92, has a substantially lower rate of fire than it's smaller counterpart, partly because of larger size of the ammunition generally, but mostly because the ammunition, on account of it's size, it is now seperate-loading, with projectile and charge loaded seperately. The ammunition uses a disintegrating case for the propellant, with a 170x975mm round.

The gun itself has the aforementioned 17-round autoloader and carries twenty-seven rounds overall capacity, the other 10 rounds in the hull and some in the turret, and rounds can be unloaded once in the breech. The gunner can change between rounds easily, (qv). The main gun have highly efficient muzzle brakes of the pepperpot type, with up to seventy per cent efficiency. The original Sh91 main gun had a quadruple-baffle type. The pepperpot type was chosen because, unlike more traditional muzzle brakes, it acts somewhat like an extension of the barrel and will not damage fin-stabilised rounds or other ammunition with that property, such as Gun-Launched Anti-Tank Guided Missiles, or GLATGMs. It should be noted that the high ammunition capacity comes from rear compartment stowage; the rounds are not low-power with reduced propellant loads. Quite the opposite, in fact - the Sh91 is an very high-pressure main gun.

The 170mm gun fires the following types of ammunition, excluding GLATGMs:

Depleted Uranium - Armour Piercing Capped, Ballistic Capped, Fin-Stabilised, Discarding Sabot, Tracer. DU-APCBCFSDS-T, Sh95. A larger variant of that used in the Sh93 130mm gun. Estimated armour penetration against RHAe is 2500mm at a thousand metres. Also in training form.
Triple-Stage High-Explosive, Anti-Tank, Capped, Ballistic Capped, Multi-Purpose, Tracer. HEATCBC-MP-T, Sh95B. Again a larger version of that in the Sh93, it is highly advanced with a triple-stage warhead, designed to take on the Sh99 itself. The warhead would not only have to penetrate an exterior heavy ERA layer, but then a NERA layer of armour and finally the tank's armour itself. To streamline the very blunt 'fist' of the projectile in flight, it is ballistic-capped. While the cap breaks off on impact it is slightly detrimental to armour-piercing capability. Estimated armour penetration against RHAe is, at very best, 3300mm. Also in training form.
High-Explosive, Fragmentation, Tracer. HE-FRAG-T, Sh90. An original from the Sh91's usage as an indirect-fire artillery piece, it is not capped as high muzzle velocity is not particularly important. It has a 8kg explosive charge and a fragmenting body. Also in training form.
Depleted Uranium - Armour Piercing Capped, Ballistic Capped, Fin-Stabilised, Discarding Sabot, High-Velocity, Rocket-Assisted, Tracer. DU-APCBCFSHVRADS-T, Sh08Y. A larger version of the one fired in the Sh93 (Sh08T), it is an improved variant of the standard APCBCFSDS-T with an acronym every bit as lethal as the round itself. It is designed to take on vehicles such as the LY6 and LY6A1, at longer range.
White Phosphorous Smoke, Tracer. WP-T, Sh85. Also used with the original Sh91 main gun, it has also been unofficially used in an offensive role.
Canister, Tracer. CANISTER-T, Sh89. Also developed for use with the Sh91, it turns the 170mm gun into a giant shotgun.

Secondary armament is the turret-roof-mounted Sh92R (Year Type 92), and is a large weapon firing from a closed bolt so as not to suffocate the crew with fumes. It is not a chain gun, i.e. a gun that is operated by electricity rather than gas or recoil, because it was decided that such a weapon would be more survivable, not having to depend on an external power source.

It has two large loading trays underneath the mount, whereupon ammunition is then fed up into the feed chutes on either side; the intention is to provide ready clips of both various anti-tank ammunition and also HE, or canister. A large mechanical lever is located below the breech to switch feed, although since the weapon operates from a closed bolt the round in the breech must either be fired off or ejected by means of a number of ready compressed-air charges, or mechanically by the gunner. As each round weighs around 4kg, the gun's feed trays are charged in clips of three from ready trays around the turret, placed to allow easy loading of the heavy clips. Each tray holds 30 rounds.

The 57mm gun is mostly similar to the weapons firing the 50x300mm round, in particular the LY106, but has slightly better range, armour-piercing capability and slightly higher HE effect. The weapon uses airburst anti-armour ammunition as well as it's standard APCBCFSDS and HE-FRAG types. The extra length of the case, a 50% increase on the 50x300, allows considerably increased power.

The Sh92R is rifled, autofregatted and stress-hardened, and uses solid-propellant Electrothermal-Chemical Technology, fast becoming the norm nowadays. It also has a small fume extractor near the end of the barrel. ETC technology is a form of ignition of the propellant, similar in a way to ETI or Electrothermal Iginition, a lower-powered technology. ETC ignition releases further chemical power in the propellant to effectively increase muzzle velocity and energy, and thus penetration, and allow the gun to lob heavier shells. It is a far more practical and mature technology than such things as coilguns and railguns, which strive for much the same thing. It is designed for use against targets occupying the grey area between rifle-calibre-machine-gun-suitable targets and heavily armoured fighting vehicles such as MBTs, this grey area covering vehicles such as light and medium IFVs.

Tertiary armament is twofold, the last mounted gun armaments being two 7.7mm Sh94 GPMGs, or General-Purpose Machine-Guns, the first coaxial with the main gun and mounted directly to the left and above and the second mounted on the commander's hatch on a combined pintle-ring mount, because, in jungle conditions, or indeed most conditions, the slow-firing, bulky autocannon would not be suitable against close or closing infantry targets, given a high miss probability afforded by the plentiful cover of the jungle and the low ammunition for the 37mm. The weapon, incorporating a disintegrating belt feed, fires from a Heckler and Koch roller-locking bolt system with a standard, unmodified cyclic RoF of 1200-1350rpm, adjustable with the incorporated gas regulator, and has 10500 rounds stowed inside the vehicle, again with the possibility of extra belts stored outside. Lastly, grenade launchers, with sixteen on either side of the turret and each individual one reloadable and aim-able on the traverse and elevation axes, can fire smoke, illumination, and fragmentation/countermeasure rounds, the latter as part of the countermeasures system, see below. As a last resort, small firing ports are provided, one to the right of the mantle and one on each side of the hull. Provision is made for the storage of small arms up to assault rifle size, i.e. the Ekraysian standard Sh91, with one stored in the turret on the right next to the commander and the gunner’s and driver’s next to the latter crewmember on the right of the escape hatch, as well as room being made for a box holding 450 rounds in 30-round magazines, or the equivalent in other small arms calibres.


Countermeasures


The Sh99 incorporates the tried and testede ORDEN countermeasures system, an Ekraysian system similar to those of many other nations and operating on the same principle. It detects threats by millimetre-length RADAR and LIDAR, with sensors on hull and turret providing 360° coverage, each working in tandem to protect each other against anti-countermeasures and for extra reliability and detection. The system can react in milliseconds, as low as 0.377 seconds. In addition, it registers the surrounding area, searches for any signs of objects inconsistent with the surrounding area (such as infantry weapons or antitank weaponry, for exmaple) and registers them with the crew, can, using BANCODS, receive threat data and simulate their positions for gunner and driver, as well as conducting offensive operations such as the independent firing of ATGMs to meet threats while the main armament is engaged or otherwise innefective
It works by hard and soft kill; the system has a catalogue of missiles and the ability to recognise them, engaging the most dangerous and nearest of those first. If the tank has standard armour thick enough to withstand the missile on the bearing it is headed, fewer or no countermeasures will be taken against it. Soft kill consists of a laser dazzler, electro-optical jamming, electronic jamming, and chaff. Hard kill deploys specially-designed fragmentation grenades and also has the ability to electronically detonate some of the ERA bricks if applicable, prematurely. More than two grenade-launchers are never fired simultaneously, so that reserves are always available to further counter the threat. ORDEN incorporates a quadri-redundancy jamming system.


Electronics & Vision


The tank’s many computers are organised into larger, main computers, each easily controllable. The countermeasures central computer does as it’s name implies, controlling the countermeasures and housing the catalogued signatures for incoming missiles. The engines computer handles all matters to do with terrain and the engine and serves the fairly unique purpose of limited microscopic delay of the firing of the main gun over rougher terrain, monitoring all elements of it and adjusting the tank accordingly. Armament computers house fire control data and provide gauges for the functions of the main gun and missiles fired, as well as providing gunner or commander for full control of the main gun or it’s breech load. The safety computer controls all fire-suppression and the like, while lesser functions are not allocated directly to the main computer. Several toughened LCD displays dominate the turret, with the ability to see any of the computer’s many displays on each.

It should be noted that the tank has many more computers that are merely relayed to centralised points rather than single computers for each of these major areas; this would lower computing power and significantly increase burden on the system.

The entire vehicle’s systems have EMP-proof Gallium Arsenide circuitry. A system called BANCODS (Battlefield Network, COmmunication, and Data-Sharing) has the ability to control radio and all other communications devices inside and the ability to electronically share data with any other relevant battlefield unit. Larger, smaller, more and less capable versions are used in helicopters to aircraft carriers, all compatible with each other, which means that the tank's commander can talk to the admiral of a carrier task force at his own convenience, should he have frequencies. Another system allows the driver to have limited, basic control over the main gun in an emergency or the unlikely case that he’d be on his own, transforming the tank into a kind of self-propelled gun with fixed main armament.

It is unique in having it's own small Electronic Warfare module, the controls for which are at the commander's station. It uses radiated Electro-Magnetic (EM) energy to receive, intercept if possible and/or jam incoming radio signals. It can also disrupt lower-strength radar waves by means of interference - it can control Chaff grenade usage - and aid in disrupting missile guidance. Not much has been released by the army, but it is known to be called shénlóng (神龍), the mythical Chinese dragon that controlled the weather.

The commander’s station has an independent periscope, the M-DRV-21, with day and night vision, full stabilisation and traverse, and laser rangefinder, the thermal image from which can be displayed on one of the multifunction screens. It can also be used for aiming and firing and is slaved to the main gun and relevant systems. Data can be fully shared between this and the gunner’s similar M-577R, a dual magnification optimised primary sight, which has integral laser rangefinder and a Zeiss Optronik thermal sight. The thermal sight uses standard Army common modules, with 120 element cadmium mercury telluride, CdHgTe (also known as CMT) infra-red detector array operating in the 8 to 14 micron waveband. The sight is fitted with a CE628 laser rangefinder from Zeiss Optronik. The laser is a Neodinium Yttrium Aluminium Garnet, (Nd:YAG) solid state laser. The rangefinder can provide up to three range values in four seconds. The range data is transmitted to the fire control computer and is used to calculate the firing algorithms. Also, because the laser rangefinder is integrated into the gunner's primary sight, the gunner can read the digital range measurement directly. The maximum range of the laser rangefinder is about 13,000m with accuracy to within 20m. In addition, the vehicle has a backup mechanical computer in case this fails, and then (a point which illustrates the capabilities of the gun) an indirect-fire sighting system with gunner's quadrant. Direct-fire sights have a switchable zoom, in the case of optical sights and mechanical computer, and a seperate infrared system for it. The Sh99 is equipped with two independent GPS systems and an inertial navigation system.
A large, pintle-mounted lift-and-swing type hatch is provided for the driver, inset into the hull like in the Challenger, whose station is in the left of the vehicle, and opens to the front. There are two observation periscopes in the driver's hatch, plus one to the left of his section, for use when driving closed down. The central periscope (in the hatch) can be exchanged for a passive IR-sight for night operations. A larger, mine-blast-reinforced escape hatch is provided under the driver's seat.

All of the tank's combat systems incorporate at least triple redundancy.


Crew, Safety & Amenities


Seven 11kg Halon-Replacement bottles are mounted throughout the tank, four on the right behind the driver’s station and three next to the refreshments machine, which can serve hot or cold water and two hot beverages of choice. Pipes and hoses are connected to them and a fire/explosion detection and suppression system is fitted, directing the extinguishing effort towards the flames. A further three fire-extinguishers are provided, two in the turret and one on the left of the driver. The driver’s and one of the turret extinguishers are Halon-Replacement 2.5kg items while the other turret fire extinguisher is of the same weight filled with ABC powder. Use on sensitive equipment, however, will cause damage but use of this type of extinguishing substance prevents re-ignition.

The tank's rear compartment can carry four fully-loaded infantry in an emergency by dispensing with some ammuntion carriage.

The self-contained NBC system doubles as the air-conditioning system for use in hotter times - and it is always hot in Ekraysia - and produces up to 4 mbar (0.004 kp/cm²) over-pressure inside the vehicle. Armoured, fireproof bulkheads separate the engine compartment, fighting compartment, and driver’s compartment, with a further bulkhead in the latter to separate the APUs.



Engines & Running Gear


The main engine is front-mounted, providing an extra degree of protection, and is an Axon 63.0 litre V16 Multifuel optimised for Diesel, tropicalised as it is an Ekraysian engine, with exhaust turbocharging, which develops 2700 brake horsepower (bhp) at 2900rpm. It is started by fifteen 12-volt/125Ab batteries and has a 24-volt electrical system, and the engine is coupled to an automatic Axon 97rK transmission, integral power brake included, with seven forward gears and two reverse. This is coupled almost directly to the engine giving a compact powerpack which can be exchanged within 15 minutes. With this combination and with a standard load of ERA, NERA, but no slat armour, the vehicle has a governed top speed of 40.15mph (64.62kph) and a maximum reverse speed of 20.8mph (33.47kph). The standard fuel tanks hold about 2000 litres, giving about 580km road range, although extra fuel tanks are often carried. The exceptionally wide tracks (840mm), with rubber-bashed end connectors, have removable rubber pads and use 107 links on each track. For use in icy ground, up to 24 rubber pads can be replaced by the same number of grousers, which are stored in the vehicle's bow when not in use. The first two sessions of the side skirts are heavily armoured, and must be raised for rail transport. The remaining sessions are made of standard rubber and metal fabric and are hinged to swing upward if necessary. The APUs, or Auxiliary Power Units, are two 37hp MYS Multifuel, also optimised for Diesel, housed by the left of the driver in the hull front.

The Sh99, despite the very high torque of the engine and large tracks, is unlikely to shed a track and high maneuvrable in respect to turning circle. It has a width to length ratio of 1.35:1. The suspension system is the old, heavily modified Christie type, unique among modern tanks; while reducing internal space due to the large individual suspension units - it will be noted that the tank is unusually wide to cater for this - it allows for incredibly fast running, usually exceeding theoretical design speed. The tracks have been toughened, bolts doubled up on either side and flexible materials used in order to run at up to 52mph without blowing up engine, gearbox, driveshaft and wheels.

The Sh99 has the potential to go faster with it’s large engine but instead lower gear ratios were chosen, partly because the tracks were not designed for speeds [much] above the vehicle’s current top speed. Instead, this choice enabled better acceleration and better towing and heavily-laden performance. The tank runs on interleaved road wheels to spread weight out on the Ekraysian terrain, several of which joined together form the idler. Although a concious decision by the design team, it is a maintenence issue, although it's combination with incredibly wide tracks give it an excellent low ground pressure on Ekraysian terrain, the combination giving one of, if not the, best ground pressure figures in tanks today.

The tank, as standard, has a heavy bulldozer blade, in other countries only fitted in engineer tanks, which can be used for mineclearing duties, to dig itself into a hull-down position, but most importantly to help clear a way through the Ekraysian jungle.


Variants


None.


Export


The standard price of the Sh99 is:

$19,000,000

Only available to nations in alliance with the Federation of Ekraysia. Bear this in mind.