HT9A7 Yvernyr Main Battle Tank, 1st Noble Guards Cavalry Regiment the Imperial Life Guard, on training exercises in Barony Myrstirei
HT9A7 Block 2 Yvernyr Main Battle Tank, 1st Noble Guards Cavalry Regiment the Imperial Life Guard. The Block 2 version of the HT9A7 is equipped with additional armour, including a spaced armour block along its frontal arc, thicker roof protection and extended side armour, but compensation for this with the use of titanium alloys in place of IRHA in areas of the appliqué armour ensure that the weight increase is marginal, at 78t. The electronics suite has been greatly modified, with significantly faster processors allowing for faster and more effective target recognition. A modified RWS sporting thicker armour and better stabilisation together with the addition of sensors to the APS suite round off this comprehensive update to the original HT9A7.
HT9A7 Prototype Model (128mm L/55) | HT9A7 Prototype Model (140mm L/50 ETC) | HT9A7 Prototype Model (120mm L/55) | HT9A7 Prototype Model (252mm Demolition)
HT9A7 128 Entry Standard w/ Transit Equipment (Crown Army of Anemos Major) | HT9A7 128 Block 2 Entry Standard (Crown Army of Anemos Major) | HT9A7 140 Export Standard (Minnysotan Army)
- Specifications
- Overview
- Main Armament
- Other Armaments
- Armour
- Active Protection System
- Electronics
- Mobility
- Crew Amenities and Survivability
- Concluding Comments
Promotional PDF
Designation:
Numerical Designation: HT9A7/IOCY
Name: "Yvernyr" - "Wyvern"
Key Data:
Crew: 3 (Commander, Gunner, Driver)
Cost: 16.7 million NSD
Dimensions:
Length: 8.1m (Hull)/
Height: 2.7m (Turret Roof)
Width: 3.8m (4.2m w/ Modular Side Armour)
Weight: 77t
Performance:
Maximum Speed: 72kph road speed (governed).
Cross country speed: 52kph
Acceleration: 0 to 32kph in 4.8 seconds
Operational Range: 515km
Armament:
Main Armament: 128mm SC10.8 55 calibre solid propellant smoothbore cannon (42 rounds, 25 in autoloader magazine)
Co-axial weapon (left): 20mm Arsenal Karonin M.28 Autocannon (600 rounds)/12.7mm MG/H8A3 (1500 rounds), or other modular block compatible weapons.
Commander's weapon: 12.7mm MG/H8A3 on Remote Weapons System (powered), interchangeable with other armaments.
Additional: 12x mounted multipurpose grenade launchers, modular systems allow for further options.
Protection:
Passive: Calumnis-3 (metal-composite matrix outer layer, (N)ERA, composite tiles, DU alloy mesh, IRHA plates/hull, fibreglass/rubber/Spectra spall liner)
Active: Solothel Active Protection System
Crew Protection: NBC protection (main + auxiliary), pentafluoroethane crew compartment fire extinguishing, Halon 1301 + foam fuel tank extinguishing and self-sealing suite.
Electronics:
Io FCS
SAIC Combat Networking
Power:
Propulsion: MA.252/mod H 2,200hp (1,640kW, steady state) 10 cylinder opposing piston diesel hyperbar.
Transmission: Automatic (8 forward, 3 reverse).
Suspension: In-Arm Hydractive
Power/Weight: 28.57hp/tonne
Conceived as a direct result of the Holy Office of War’s 1999 Request for Information concerning the feasibility of creating a domestic main battle tank to replace those then in service with the Crown Army of Anemos Major, the HT9 (Irdentsyr) line of armoured fighting vehicles was initially envisioned as a domestic replacement for the many tanks then in service with the Second Holy Empire of Anemos Major. The aged HT7 Lakontyr, a relic of the 1970s, the failed HT8/N Fyrdestyr tank, and the Leclerc obtained from abroad to make up for the subsequent shortfall in the Crown Army’s tank inventory, came together to create an increasingly politically and military unacceptable array of vehicles, and concerns within the Holy Office of War that this arrangement would not be able to continue satisfactorily throughout the first decade of the 21st century resulted in the distribution of funding for initial development and feasibility confirmation of a domestically produced main battle tank to come into service during this period. Within one year, this program was greatly expanded, dubbed ‘Project Fiensietyr’ and renewed with the avowed goal of providing the Crown Army of Anemos Major with a fully updated stock of armoured fighting vehicles by the end of the decade; however, despite this ambitious rebranding, the individual components of this project operated largely independently of each other, and the main battle tank project was a notable example of this. Politically pressured into creating a fully domestic tank model, the Holy Office of War provided a substantial amount of support to those development teams participating in the initial stages of the competition, fully funding and aiding five separate development teams past the conceptual stage up to the creation of a prototype; unlike the vast majority of the objectives of the 1994 Armed Forces Modernisation Program, the failure of the Fyrdestyr and the emergency acquisition of the Leclerc in the following year meant that this was one of the few portions of said program which had still not been completed, and the continuing pressure from above to remedy this resulted in a significant amount of interest within the Holy Office of War concerning the future of the new tank acquisition program.
By the initial ‘conceptual’ stage, it was widely recognised that only three designs were serious contenders for the contract; those of Grunwalder Heavy Industries, an ex-Ragonsian concern, Symoirei Vehicle Group and the Imperial Foundries of Anemos Major (who had only acquired a vehicle development group from the remains of Myrstirei Mechanical in 1997). However, despite an apparent variety of choice, the situation quickly turned against the desires of the Holy Office of War. The Imperial Foundries of Anemos Major found themselves forced to re-tool Myrstirei Mechanical to provide sufficient productive capacity to meet the demands of the Armed Forces following the sudden issuing of a contract for the complete replacement of the AR4 (FAMAS) rifles then in service with the domestically designed AR5 (a problem which would have its own dire consequences for IFAM) and, in 2000, Symoirei Vehicle Group took the Anemonian Arms Industry by surprise when it filed for bankruptcy and announced its withdrawal from the competition as a result of a failed endeavour into the civilian vehicle market that resulted in uncontrollable losses within two quarters. Although Grunwalder Heavy Industries proposal for a heavily modified, up-armoured Leopard 2A6 did fulfil the desired design’s basic necessities, there were a variety of reasons that made this option entirely unacceptable to the Armed Forces community and the Anemonian arms industry as a whole. Firstly, the adoption of a Leopard 2A6 was essentially an admission of failure by the Holy Office of War concerning the potential construction of a domestic main battle tank; for the ministerial level staff, the political capital at stake was far too great, despite the apparent lack of an alternative. Secondly, however, Grunwalder was a unique corporation within the Anemonian state due to its legal position. While the vast majority of the Anemonian arms industry, most certainly including and going beyond the largest corporations was listed as IECpl (public sector), Grunwalder’s status as an arms production concern acquired from abroad meant that it had retained its rights as a private sector concern. This subsequently meant that the Holy Office of War was unable to secure the armament security that it so fervently imposed upon the vast majority of the Anemonian arms industry, making Grunwalder all but unacceptable as a choice. The lack of alternatives was, to say the least, an embarrassment to those involved; extending the program deadline to allay any calls of unfair play, backroom negotiation and dealing was done to ensure the creation of a force potent enough to present an alternative from within the public sector.
As a result of these concerted efforts, therefore, 2001 marked the entrance of another contender for the contract, standing against Grunwalder Heavy Industries. Though such a cooperative arrangement would previously have been thought to be impossible, sufficient pressure from the Holy Office of War resulted in the creation of a hitherto unseen conglomeration of corporations within the Anemonian state. Known as FOAM, or the Fierei-Oblastinei Automotives and Metalworks, this front company was established to house this joint venture between a number of Anemonian vehicle, metal, arms and electronics industry concerns, together with a variety of smaller corporations and the Holy Office of War’s Directorate of Technological Research and Development (DITI) which had, in 2000, acquired the remnants of Symoirei Vehicle Group with government funding. The design produced by the group drew heavily on SVG’s earlier conceptual work on a tank they had labelled the ‘Irdentsyr’; however, it had been highly refined and polished to produce a highly unorthodox and unique creation, as was to be expected from such a conglomerate. As a result, and recognising the forces arrayed against it, Grunwalder Heavy Industries announced their retirement from the competition mere days before the designation of FOAM as the preferred bidder for the HT9 contract. The subsequent developmental process was to last until January 2008, when the first field testing of the Irdentsyr tank occurred in battlefield environments, the program costs having remained, surprisingly, largely stable and on schedule during this period.
By the time the first test model reached the shores of Asakura in January 2006 for field testing, the Irdentsyr had gone through six different iterations to reach the HT9A6 Irdentsyr Kalontris. The tank largely followed the accepted lines of design for its time; utilising the 140mm SC9.15 50 calibre Electro-Thermal Chemical smoothbore cannon and a 40mm cannon as a co-axial weapon, the tank utilised the combat-first, comfort-later design approach of the Leclerc to maximise its combat effectiveness. The prevailing view at the time was that the limited ammunition capacity of the tank forced upon it through the use of a 140mm main armament meant that extended combat was not an option, and that, therefore, amenities for extended combat were unnecessary, allowing the design to feature much higher levels of protection that previously envisioned. Though this view was to dictate the subsequent development of the Irdentsyr tank, studies conducted in 2008 revealed an uncomfortable truth concerning the state of global armoured forces. A significant gap, in fact, existed in the capabilities of a variety of nations; with a variety of internationally predominant tanks with 1970s-80s developmental origins, such as the Leopard 2 or M1A2 Abrams, on one side, and recently developed, highly effective, armed and armoured tanks on the other, such as the LY4A2, M-21A2 and the AY2-1E on the other, it was found that the 140mm L/50 ETC armament was too powerful for the former and not strong enough to penetrate the frontal armour of any of the latter, making it, ultimately, an incredibly bulky, power consuming and ammunition restricting choice of armament with no clear advantages. It was as a result of this testing that FOAM lost the ‘arms-race’ mentality that had driven tank development worldwide for so long, and adopted a more practical mindset; objectives shifted, and changed.
The decision to structurally upgrade the HT9A6 Irdentsyr Kalontris, which was due to enter Anemonian service in the summer of 2006, to what is now known as the HT9A7 was based on the decision to retool the HT9 from being an expression of technological superiority to, in true Anemonian fashion, a practical weapon on the battlefield. Of note was the armament utilised at that point by the Irdentsyr; the objective was to create a weapon that was smaller than the 140mm L/50 ETC cannon previously used, and, through means other than creating rounds big and fast enough to destroy the enemy’s frontal armour, create a tank nonetheless capable of engaging its modern counterparts head-on and emerging victorious. The weapon eventually chosen was a 128mm 55 calibre solid propellant gun, and the solution was the utilisation of adaptable ammunition that would, in a leap far beyond the simplistic design philosophies employed by so many, accomplish what larger models of weapon could do in a far more efficient and effective package.
The final prototype model of the HT9A7 was unveiled in 2008 by FOAM to the Holy Office of War. Since the production of the Kalontris in 2006, the vehicle had been radically altered; its powerplant had been made more powerful, the armour layout had been shifted radically, but the advances made in other areas had been made in leaps and bounds. With an overhauled electronics suite equipped with a highly effective countermeasures system, networking that far exceeded the expectations of any within the Anemonian military establishment and a modular armament/armour arrangement that made the new main battle tank one of the most flexible vehicles of its time, FOAM had established the HT9A7 as an armoured vehicle that would perform as a superior vehicle on the battlefields of today and retain the flexibility to advance with the flow of technology under the auspices of the approaching future. Initial models were equipped with 120, 128 and 140mm main armaments, together with 12.7 and 20mm co-axial weapons, but the ease of parts replaceability and made the scope for further additions virtually limitless.
Adopted by the Crown Army of Anemos Major in March 2009 as their new main line battle tank, the HT9A7 was named the Yvernyr, Wyvern, symbolic of its place as the protector of the nation, and its distribution to field formations commenced soon after. Familiarisation was a process that took the best part of the rest of the year, but by early 2010, the Yvernyr was seeing service with frontline units in the forested terrain of Asakura, where its performance painted the picture of a vehicle that far surpassed its predecessors. Further deployment with the Crown Army to higher intensity combat areas only served to build upon this image; proficient in all areas, from support to strikes, it proved itself not only to be a worthwhile investment, but, as the product of ten years of research and development, one of the finest vehicles of its time.
The HT9A7 is the embodiment of innovative design married with the unrivalled engineering of the Holy Empire of Anemos. A mighty vehicle rivalled only at the highest end of the spectrum, it is a unique armoured vehicle that possesses the capacity to defeat and destroy virtually any opponent it encounters on the battlefield, while remaining capable of adapting to advances in technology and necessity to perform beyond its already impressive specifications. Ninety-five thousand of these vehicles already equip the Imperial Armed Forces of Anemos Major, with countless more on the production lines; serving across every branch of the Crown Army, from the First Army within the Citadel of Anemos Rei to the Tenth Army’s amphibious assaults, it is a vehicle which answers every demand made of it, whether it is flexibility across any battleground, efficiency in any role, or superiority before any enemy.
The 128mm SC10.8 55 calibre solid propellant smoothbore cannon was developed as a replacement for the 140mm SC9.21 50 calibre Electro-Thermal Chemical smoothbore cannon utilised in the HT9A6 main battle tank. Opting to use a conventional propellant and smaller round for ammunition and weight efficiency purposes, the SC10.8 makes up for its decrease in comparative firepower through a number of ammunition based solutions designed to maximise its utility in head-on-head combat with enemy main battle tanks of any standard, giving it per-shot killing power that far exceeds the performance of its main armament on paper.
Though the 42 rounds standard ammunition carrying capacity of the HT9A7 is high, when considering the combat intensity and periods that the tank is likely to face, there are a number of reasons for it. Firstly, it gives the HT9A7 combat flexibility where other armoured vehicles simply opt for larger guns; though it is not intended that the HT9A7 will enter and remain in combat for periods of time that allow for the complete utilisation of the 42 rounds carried by the tank, it does mean that the HT9A7 does not have to rely upon high frequency maintenance and resupply, allowing it to respond flexibility to unforeseen circumstances on the field of battle. Secondly, however, a combination of ammunition mixture and the usage of high performance GLATGMs and guided ammunition actually decreases the combat carried anti-tank ammunition of the HT9A7 to about 25 to 30 rounds overall; as a number of high explosive rounds must be carried to ensure the responsiveness of the HT9A7 to a wider variety of potential threats, as well as, potentially, other specialist rounds, the higher ammunition capacity allowed by the 128mm gun is necessary to ensure that the HT9A7 is able to retain its battlefield endurance together with the flexibility of response that it requires.
The SC10.8 is a 128mm solid propellant smoothbore cannon with a length of 55 calibres (6.6m). The barrel itself is constructed of autofrettaged steel. Responding to problems concerning the decreasing barrel life of modern smoothbore guns due to the increased performance of propellants, it utilises a barrel construction that departs from the chromium-lined steel barrels of most modern guns. With a silicon nitride (Si3N4) barrel, the SC10.8 aims to use ceramic liners to decrease the effect of propellant erosion of the barrel when compared to chromium gun barrel linings, and gives the gun either a greater service life or the ability use increasingly powerful propellants. However, as a ceramic, silicon nitride is also very brittle, and due to the inability of the material to undergo the same autofrettaging process used by steel barrels to induce pre-compression in the gun barrel, it also utilises a 35% glass reinforced polymer composite overwrap to induce the pre-compression necessary to compensate for the brittleness of silicon nitride, utilising computer modelling to determine the deposit locations and angles necessary to achieve the desired levels of strength and stiffness within the gun barrel itself. The result of this is that the SC10.8’s gun barrel, through significantly decreased erosion in comparison to chromium-lined barrels, is able to withstand propellant-induced damage for longer periods of time. The weapon’s thermal jacked is also made of 35% glass reinforced polymers, and, opting not to utilise a standard pattern bore excavator, the SC10.8 chooses instead to utilise an automatic compressed air fume extraction system at the rear end of the gun barrel to prevent oxygen depletion and other potential effects on the crew.
Recoil mitigation is achieved through two primary methods; directive and absorptive. The porting-type muzzle brake employed at the forward end of the SC10.8 redirects propellant gases to counteract the recoil forces generated with the firing of the weapon. Furthermore, the weapon features the hydro-pneumatic recoil mechanism utilised on most modern tank armaments today, together with a pair of hydraulic retarders located to either side of the weapon (with four originally used with the SC9.21). Overall, these recoil control mechanisms permit the HT9A7 to limit recoil forces and regain stability quickly after firing, increasing the overall accuracy, aimed firing rate and mobile engagement capabilities of the tank. Stabilisation is achieved via two independent electro-hydraulic systems with independent horizontal and vertical stabilisation (full dual-axis electro-hydraulic stabilisation), as well gyro-stabilisation, further increasing the mobile engagement capabilities of the HT9A7.
Though the round used by the SC10.8, the 128mm, is smaller than the 140mm originally envisaged as that to be used in the HT9, its size, together with the potential need to replace the main armament of the HT9A7, resulted in the utilisation of an autoloader with the HT9A7. In general, 25 rounds are stored in the autoloader with 17 additional rounds in storage for later use. As a number of rounds (GLATGM, MRKE, APFSDS and HE in combat use, with other potential rounds for specialist purposes) are used in a largely interchangeable manner on the battlefield, the autoloader system used within the HT9A7 could not, by default, be a simple bustle system as used by many other main battle tanks, while the carousel system favoured by many Eastern Bloc armoured vehicles was also not a valid option due to its storage inefficiency. As such, the system utilised is a rotary belt type bustle system with a storage capacity of 25 128mm rounds (regardless of type) behind the crew. The control system uses a combination of virtual memory-stored location records of rounds and bar code designations to correctly select and prepare rounds; rather than automatically loading rounds upon firing and spent case extraction, the gunner is able to select a number of potential options; as well as being able to set the autoloader to ‘single type automatic’, which causes the autoloader to consistently select a single type of round and load it upon extracting the spent casing of a firing round without confirmation, he is also able to set up a ‘firing list’, selecting a number of rounds in firing order for the autoloader to automatically select and load, and can also utilise a manual confirmation system where he selects a desired round prior to loading, allowing the Anemonian gunner to make full use of the wide selection of rounds employed within the HT9A7. The average rate of fire of the autoloader-equipped cannon when on automatic loading is 12 rounds per minute, but this figure decreases when the gunner opts to utilise individual selection.
In terms of ammunition used, there are four primary types of ammunition used with the SC10.8 128mm gun; M07/S Kinetic Energy, M07/E High Explosive Dual Purpose, M07/mod M Gun Launched Anti-Tank Guided Missile and M07/mod I Medium Range Kinetic Energy. As the gun is a smoothbore, ever round uses some form of individual stabilisation to maintain its firing trajectory. The first two are conventional propellant, conventional trajectory rounds, while the third is a rocket-propelled, top-kill HEAT missile and the latter is a range extended, LOS/BLOS forward/top kill guided KE round. The propellant utilised in the standard rounds is a combination propellant (60% nitrocellulose, 20% nitroglycerine, 4% RDX, 15% diethylene glycol dinitrate with 1% of other content and 55 grams of igniter); the utilisation of a low level of RDX in place of the nitroglycerine used in other propellants provides the 128mm round with a higher level of more stable propellant performance while nonetheless restricting the increase so as to retain a practically sustainable barrel service life. The M07/S Kinetic Energy round is an armour-piercing discarding sabot round, with a kinetic energy penetrator constructed out of a depleted uranium alloy (composed of uranium, vanadium and niobium for machining purposes), creating a high density KEP which, combined with the high muzzle velocities generated by the powerful propellant mixture utilised by the round, forms a highly lethal round against most conceivable battlefield targets. The M07/E is a High Explosive Dual Purpose round; fin stabilised like the M07/S, it utilises a tandem charge warhead together with a fragmenting casing, giving the HT9A7 the ability to engage both armoured and unarmoured targets with what is essentially a shaped charge and anti-personnel round in the same munitions system. However, though these two conventional pattern rounds are highly effective, utilising a number of design features to give them performance and flexibility that surpasses its competition, the core of the 128mm SC10.8’s effectiveness as a modern tank armament lies in the other two munitions it utilises for the sole purpose of hunting other tanks. The M07/S is, as a 128mm solid propellant KE round, incapable of penetrating the frontal armour profile of most top-tier main battle tanks in service today, and as an anti-tank round, the M07/E is at a natural disadvantage due to the frequent use of NERA, composites and slanted armour on modern tanks. Rather, the heart of the SC10/8’s anti-tank capabilities lies with its other rounds.
The M07/mod M is a GLATGM (gun-launched anti-tank guided missile) utilising a HEAT warhead and a three stage seeker system to defeat the vast majority of existing tanks at extended ranges by accomplishing highly countermeasure-proof top-kill attacks. The seeker head uses a combination of millimetre-wavelength radar, passive IR CCD sensors and a semi-active laser seeker to acquire and track the target while in flight, decreasing the effectiveness of single-purpose countermeasure units against the missile. Utilising a soft-launch system, the M07/mod M clears the barrel of the gun before engaging its flight motor, thus greatly increasing the service life of the barrel itself when used in conjunction with the GLATGM. With folding stabilisation fins used to fit as large a missile as possible into the HT9A7’s 128mm gun barrel, the missile’s internal seeker system tracks the acquired enemy target and rises to the appropriate trajectory before entering its terminal descent, placing itself into a high speed, top-kill position to virtually guarantee a kill; potential targets range from a wide variety of land vehicles to, potentially, landing ships and helicopters. The warhead of the missile is a tandem charge; upon striking the enemy target, the impact detonation mechanism first detonates a smaller ‘initial’ charge to activate and eliminate the ERA lining of the tank; furthermore, the ‘initial’ charge utilised by the M07/mod M takes advantage of the increased capacity of the missile by being somewhat larger than that of the standard M07/E round, giving it enough explosive force to either destroy or damage NERA/NxRA blocks on enemy tanks and thus leave them vulnerable to the larger shaped charge warhead located behind the initial charge (separated from it by a titanium diboride blast shield). The main charge is then detonated. As such, the M07/mod M not only provides the HT9A7 with the ability to defeat the lighter roof armour of an enemy main battle tank from nearly 15km away utilising an independent seeker mechanism that permits BLOS engagement, it also possesses the capacity to engage and eliminate ERA, NERA and NxRA protected vehicles if necessary. There is a three stage control mechanism on the M07/mod M that prevents premature detonation; the two safety mechanisms are deactivated upon firing the missile (acceleration-based detection) and entering the terminal trajectory (computer controlled), while a tertiary protective mechanism ensures that the delay between initial and main charge detonation is maintained to permit effective use of the tandem charge layout.
The M07/mod I Medium Range Kinetic Energy round is a rocket assisted and propelled, LOS/BLOS forward/top kill capable guided KE round, with a uranium alloy KEP at its heart but utilising rocket/fin stabilised active guidance and terminal stage propulsion to give it both range and power far surpassing that of the M07/S. The apparent inherent incompatibility of the high speed requirements of the kinetic energy penetrator and the difficulty of precisely guiding high speed, rocket propelled projectiles is solved through the utilisation of an effective terminal stage guidance mechanism that ensures that precision is mostly maintained while bringing the overall impact velocity of the kinetic energy penetrator to about 1.5-2.0 times that of a standard M07/S round. Utilising a conventional propellant to achieve initial velocity, the MRKE utilises a millimetre-wavelength radar and semi-active laser seeker to track enemies; it can be used as a Within Line of Sight round, where the gunner designates the desired target prior to opening fire, or a Beyond Line of Sight round, where the round is launched into the air and acquires a target from there. Utilising fin stabilisation and impulse thrusters to guide and occasionally boost the round in its flight path, the M07/mod I enters either a level or a ballistic trajectory and guides itself as necessary towards the enemy target. Upon reaching a given distance from the target, the ‘no-escape’ zone, the round then engages its main rocket propulsion system while shedding its seeker head to expose the kinetic energy penetrator, radically increasing the terminal velocity and velocity retention (through superior aerodynamics) of the KEP in the terminal stage of its target engagement. With a maximum potential range of nearly 12km and high levels of accuracy through an effectively utilised guidance/propulsion system, the M07/mod I retains high levels of accuracy by engaging its propulsion only after target impact is virtually assured upon entering its terminal stage. This allows the M07/mod I to bring the kinetic energy penetrator’s vast advantage against modern main battle tanks’ composite armour layout to bear at almost three times the maximum distance of a standard 120mm gun with even more effectiveness than a round fired utilising solid propellants, making it a highly effective anti-tank weapon that gives the HT9A7 the ability to engage enemy targets accurately and effectively from a significantly large ‘safe zone’.
By disassembling part of the base turret structure, not only can the L/55 barrel be replaced, the 128mm SC10.8 gun system in its entirety can be replaced. At the moment, however, the range of replacements offered by FOAM is relatively restricted; the SC9.21 140mm L/50 ETC smoothbore cannon is retained as an option by the Imperial Armed Force in the event that the 128mm main armament currently used must be replaced, while the SC8.60 120mm L/55 solid propellant smoothbore cannon, a development of the original main armament of the HT8 MBT, is also provided for use by the Asakuran Armed Forces.
The HT9A7, aside from its highly effective main armament, also features a number of other weapons.
As its co-axial armament, the HT9A7 features one of two weapons. The 20mm Arsenal Karonin M.28 Autocannon is a 20mm L/22 automatic cannon utilising a 1hp motor located within the receiver to cycle the weapon’s action, allowing for greater control over the feeding and cycling process of the weapon to ensure greater reliability and control over its firing qualities. Though many modern cannons utilise 25mm rounds and, more recently, larger developments such as the 50mm round to counter improvements in IFV/APC armour and protection, the choice made to utilise the 20mm round was one based upon a very practical consideration; the ammunition capacity of the co-axial weapon. The utilisation of a large, 50mm cannon restricted ammunition capacity to levels around 200-300 rounds overall, an unacceptably low figure for an automatic weapon. By adopting a 20mm co-axial weapon instead, the ammunition capacity was raised to nearly 600 rounds (usually a 200 APFSDS/400 HEDP mix), giving the HT9A7 a significant ammunition capacity advantage over the HT9A6. The 1hp motor powers a rotating sprocket system that feeds and removes the ammunition from the autocannon’s chamber, and a second sprocket layer feeding the ammunition belts into the weapon mean together with disintegrating links mean that the gunner can easily switch between the two types of ammunition he will be using on the battlefield. The barrel of the autocannon is constructed of cold hammer-forged steel with a chromium lining to increase barrel life, and porting along the barrel permits for gas release and redirection (though the rigid co-axial mounting makes recoil less of a problem). Another advantage of the electric control is the ability to set highly controlled firing rates for the weapon; by default, there are four firing modes used with the M.28 – Single (Semi-Automatic), Low (120rpm), High (240rpm) and Very High (400rpm) – but other rates can be programmed into the weapon if desired.
The other weapon that is available as a co-axial weapon for the HT9A7 is the 12.7mm MG/H8A3 Heavy Machine Gun. The MG/H8A3 is a short-recoil operated rotating bolt machine-gun utilising forced air cooling and forward porting to evacuate heat and propellant gases. With a barrel constructed of cold hammer forged steel, the external receiver of the weapon itself is, as a relatively new weapon, constructed of 30% glass reinforced polymer (making it relatively lightweight while remaining resistant to temperature buildups and sudden shocks), and the need for a replaceable barrel is largely removed through the installation of the highly efficient air cooling system. The ammunition is fed via a disintegrating link (a scaled up version of that utilised in the MG3/MG3R1 series’ 7.7mm ammunition), and the cyclic rate of fire of the weapon is mechanically alterable via the trigger block like the MG3 series, alternating between 450 and 750 rounds per minute as desired. The weapon itself is normally operated via a trigger located on the weapon’s single-handle (as opposed to the spade trigger used by some), but one of the differences between the infantry deployed and most vehicle deployed versions of the MG/H8A3 is the fact that they are, in fact, initial electrically ignited weapons (i.e. the initial trigger pull is replaced by electric ignition) to make them compatible with the HT9A7’s co-axial block system and greatly mechanically simplify the Remote Weapon Systems in service with the Anemonian Armed Forces. In general, two types of rounds are used with the MG/H8A3 as a component of the HT9A7 MBT; ball ammunition, for use against ‘soft’ targets, while HEIAP is employed for use against harder targets.
The co-axial station of the HT9A7 is highly flexible through its use of a quick-change/replacement layout known as the Modular Block System. The weapons systems themselves are placed in modular ‘blocks’ which are installed into a co-axial weapon ‘socket’ in their entirety (hence the electrical ignition for the MG/H8A3), while the ammunition and ammunition feed can be adapted without difficulty to fit into a small storage area located near the co-axial weapon itself (while most mechanical feed components, such as the sprockets used in the M.28, are placed within the modular block itself). Theoretically speaking, this means that almost any co-axial weapon can be installed in the HT9A7 as long as it is modular-block compatible and modified to fit the appropriate specifications; foreign heavy machine-guns and other support weapons aside, larger weapons such as 50mm cannons can potentially be retrofitted to become modular block compatible, the limited ammunition capacity of such an arrangement notwithstanding.
The roof mounted weapons station is equipped at production with the Ortel Powered Remote Weapons System. Capable of accepting anything up to a 40mm automatic grenade launcher, the station is usually equipped with the MG/H8A3 12.7mm machine gun in service. Capable of 360 degrees rotation, as well as +75, -25 elevation, the Ortel is a fully armoured RWS, utilising IRHA plating on sensitive areas like connections and optical equipment, equipped with optical, target acquisition and ballistic correction capabilities. Interfacing is achieved through a joystick for traversing and a 15-inch touch screen, which is linked in turn to a pair of cameras, one 3CCD daytime camera system and one forward-looking infra-red thermal imaging system. Both equipped with a laser rangefinding system, the gyrostabilised platform is able to offer a high degree of accuracy, even when on the move. Via the touch screen, the user is able to utilise both available optics to designate and ‘lock-on’ to targets, from where the laser rangefinder will feed distance information back to the ballistic computer which, utilising environmental data such as vehicle movement and round performance, will automatically adjust the firing arc to compensate for these. As such, the Ortel is capable of offering a high degree of accuracy, day and night, mobile or not, due to a high degree of environmental awareness and inbuilt ballistic correction capabilities that give it the ability to strike distant targets within seconds. As weapons fired from the Ortel tend to utilise electrical ignition, fire control (firing mode, safe) are all monitored and changed from within the vehicle itself.
In addition to these armaments, the HT9A7 responds to recent developments in tank development by incorporating support for a variety of additional equipment. The gun-launched M07/mod M can also be accommodated in a number of side slung box launchers like many other similar vehicles, though this approach is only used in high intensity open field combat due to the obvious disadvantage posed by the additional bulk of the missile launchers. Furthermore, in response to recent developments in missile technology, the Arteyr Anti-Tank Missile (a 240mm (fins folded) development of the M07/mod M built with a far longer range and larger warhead) can also be fitted into larger box launchers for engagements with enemy tanks.
Protection on the HT9A7 was envisaged from the beginning as a primary consideration, and as such, extensive material research and testing was conducted over a range of areas to create the armour layout currently used. One particularly crucial aspect of the design doctrine behind the armour layout in the HT9A7 is the utilisation of an armour-first, crew space-second approach to the creation of the vehicle. The significance of this approach lies in a departure from the long-period crew endurance focus seen in the design of armoured vehicles like the T-80 series of main battle tanks. Due to the increasing ammunition size of modern main battle tanks, and the increasing ability of other vehicles, based on multipurpose wheeled bases, to fill infantry support roles once covered by main battle tanks, it can be suggested that modern combat situations have reached the point where the ability of the main battle tank’s crew to operate effectively for extended periods of time stretching beyond six to seven hours of combat is worth trading off for increased armoured protection. Ammunition expenditure means that it is unlikely high intensity combat will see main battle tanks operating for such extended periods, and the high support-relief nature of Anemonian armoured doctrine means that most armoured vehicles can be replaced on the frontline when necessary. As such, the design doctrine followed with the HT9A7’s armour layout, drawing from past experience with large calibre guns and compact crew compartments from the Leclerc 140, is one that relies upon the maximisation of vehicular protection in exchange for making the crew compartment as compact as practically possible, resulting in far higher protective capabilities than a vehicle of its size would suggest.
Outer layer protection is achieved through the use of a Titanium Diboride (TiB2) based metal composite matrix with a fibreglass spall backing. This metal composite matrix, by being significantly harder than materials used in most ammunition-based applications, is capable of breaking up rounds, including penetrators, and, through the toughness of the metal composite matrix, results in the controlled distribution of kinetic energy absorbed from the round. As the controlled distribution results in the creation of a damage area only marginally larger than the size of the round from which energy has been transferred, with any spall effects absorbed by the fibreglass backing, the external protection is capable of sustaining multiple hits from anything up to the 12.7-14.5mm round range commonly utilised in modern heavy machine-guns. The resultant outer layer of armour protection is significantly lighter than the equivalent volume of RHA, and nonetheless capable of entirely stopping armour piercing small arms fire while significantly wearing down the effectiveness of high performance kinetic penetrators before they reach the armour blocks themselves.
Another component of the HT9A7’s passive protection suite is non-energetic reactive armour (NERA). In modern times, the continued utilisation of explosive reactive armour (ERA), widely used as most armoured vehicles’ first-line protection against shaped charge warheads, has been proven to be impractical and ineffective due to a number of reasons. Firstly, the explosive composition of the filler utilised in ERA results in a situation where hits against the vehicle can potentially result in collateral damage, especially in confined spaces. Due to the necessity of utilising infantry support for armoured vehicles in such environments, this means that the practicality of ERA equipped tanks is greatly decreased due to their subsequent inability to operate effectively in certain combat situations. Secondly, however, the modern development of tandem shaped charge warheads and their frequent employment in anti-tank guided missiles, where a smaller charge detonates ERA prior to the detonation of the main charge, has created a situation where the combat threats faced by the Anemonian Armed Forces are more than capable of easily defeating ERA based solutions with minimal effort through the use of a simple design aspect in their anti-tank warheads. As such, the utilisation of NERA was looked into by FOAM during the design process for the HT9A7, and eventually replaced all planned employment of ERA in the tank due to its clear advantages over its predecessor. The NERA utilised within the HT9A7 is formed out of panels consisting of a 10mm thick layer of rubber lining sandwiched between two 6mm thick plates of steel (Domex Protect 500). When a projectile hits the NERA panel, resultant outward motion by the two Domex plates increases the effective thickness of the armour in that area, providing increased protection against projectiles. Furthermore, however, the lack of an explosive element means that the NERA utilised within the HT9A7 is both capable of taking multiple hits (to some extent) and causes no resultant collateral damage, as well as being far more resistant to the effects of a tandem charge warhead; both in terms of protection and resultant damage, it is a more desirable form of protection. Cross-wise orientation of NERA panel is employed in the armour layout to ensure that the jet bulge in the first panel generated upon impact does not result in material erosion in the second, increasing the overall protectiveness of the NERA layers against shaped charge warheads in exchange for a minimal increase in volume. Overall, the result of this is that the NERA protection of the HT9A7 is both superior to that of standard ERA and parallel arrangements of NERA, giving it first-line protection against almost any shaped charge warheads thrown at it.
In terms of ceramics, the HT9A7 primarily employs nano-ceramic Titanium Diboride (TiB2). Titanium Diboride is, in terms of properties, highly similar to the titanium carbide currently frequently used in many armoured vehicles armour and armament suites; however, in many respects, it can be said to be superior. At room temperature, its hardness is almost three times that of the equivalent volume of fully hardened structural steel. Its melting point is also incredibly high, at 3225˚C, and the result is that armour blocks incorporating normal Titanium Diboride tend to be both incredibly impact resistant and capable of withstanding the high heat generation of chemical energy warheads. Chemically, it is also a relatively field-friendly material, insofar as it is more stable than tungsten carbide when in contact with iron, and less prone to oxidation at anything short of extremely high temperatures. As such, Titanium Diboride is a highly effective material when used in impact-resistant armour applications, capable of withstanding the effects of both HEAT rounds when used in conjunction with other forms of armour but, more importantly, very effective through high levels of hardness against kinetic energy rounds and penetrators. In addition, not content with stopping there, designers decided to take the high-performance characteristics of Titanium Diboride one step further through the use of modern technological developments in nanotechnology. By starting with high purity powders and running them through plasma melting and hot isostatic pressing to inhibit grain growth, the time-temperature window of densification was extended. With nanograin sizes maintained throughout, the result was the significant decline of porosity in ceramics passed through the treatment procedure, and the subsequent production of full density ceramics at the nanometer scale. Higher strength and hardness was achieved, as such, due to the resultant low-angle, high-strength grain boundaries and less dislocation within the overall structure due to the finger grain size. The resultant nano-ceramic Titanium Diboride improves upon an already superior material to create a uniquely effective and efficient ceramic for use within the HT9A7’s composites.
The three metal alloys utilised in the HT9A7 are Type 7720 Titanium-Aluminium alloy, depleted uranium based Stakalloy, and IRHA (HRc 40, HRc 48). Type 7720 Titanium-Aluminium alloy draws from the natural advantages of a titanium-based alloy (high stress resistance and toughness for its weight range, as well as corrosion and temperature resistance). In this particular case, however, the primary advantage of Type 7720 stems from its weight advantage; compared to RHA, Type 7720 is capable of providing properties close to those of ceramic materials at 38% the weight of the equivalent volume of RHA. Of course, the difficulty of machining Type 7720 makes it an impractical choice for usage across the entirety of a main line battle tank, and the result has been that the titanium alloy has not been used as the hull material for the HT9A7 out of purely practical concerns about the workability of the material.
Stakalloy is a depleted uranium based alloy used only as a mesh-based layer of armour rather than a block in itself. The high density of depleted uranium based materials means that the weight gain, despite its highly effective protective capabilities resulting from its sheer density, is prohibitive when overused, and the radiation emission, however limited, of depleted uranium makes it a material that must be approached with trepidation when utilised as a protective material. As brittle as it is dense, depleted uranium is incapable of being used effectively as a standalone material within armour; as such, it must be used within an alloy for maximisation of effectiveness. Departing from the usual uranium-titanium alloys (Staballoy) favoured in most developments of the material, the alloy used here instead is one formed of niobium and vanadium with the depleted uranium to create a more machinable material for use within the HT9A7 while retaining the high density qualities of depleted uranium (~95% of the alloy’s composition being of DU).
IRHA, or Improved Rolled Homogeneous Armour, is a metal alloy that modifies the basic chemical composition of standard RHA to create a far harder material, altering one of the base components of many modern tanks to create a more effective alternative suited to the battlefields of the 21st century. The basic chemical composition of IRHA (by weight percentage) is 93.68% iron, 0.26% carbon, 3.25% nickel, 1.45% chromium, 0.55% molybdenum, 0.4% manganese, 0.4% silicon and some impurities (<0.01% phosphorous, <0.005% sulphur). With a 1% increase in the nickel composition of the alloy and a smaller increase in a number of other elements (chromium, molybdenum and manganese), the resultant material is much harder than standard RHA whilst retaining similar levels of ductility and toughness. Weldability and machinability, of particular importance for IRHA’s hull applications, is similarly preserved at RHA levels by maintaining carbon content at ~0.26% or below. IRHA’s physical properties are further determined by the heat level at which it is tempered; HRc 40 grade IRHA, which is used for hull applications, is tempered at 529˚C, which HRc 48 grade IRHA, for applique armour, is tempered at 218˚C. The differentiation in role stems from the fact that HRc 48 grade IRHA is more effective against kinetic energy penetrators at the cost of far less resistance to fragmented munitions that HRc 40, making it more usable in applique armour (where its shortcomings are compensated for by other materials). IRHA, as such, provides the HT9A7 with all the advantages of rolled homogeneous armour but, again, goes one step further by modifying the basic chemical composition of this erstwhile material to give the HT9A7 another advantage over many contemporary armoured vehicles.
In terms of layout, the armour is separated into two parts; the armour itself, and the hull construction and interior. The armour consists of an outer layer of TiB2 based metal composite matrix over a cross-wise oriented NERA layer, another layer of the metal composite matrix, then panels of Type 7720 TiAl alloy sandwiching square tiles of HRc 48 IRHA and nano-ceramic TiB2. Beneath this is another layer of NERA, nano-ceramic TiB2 tiles structurally maintained by Type 7720 TiAl alloy, a Stakalloy mesh and a plate backing of HRc 48 IRHA. NERA layers and some armoured protection can also be found on the roof of the tank for protection against HEAT-based ATGMs. The hull itself is constructed of HRc 40 IRHA. The tank’s interior is equipped with a spall liner made of 20% glass composition fibreglass backed by Spectra and rubber; the energy is expended against the fibreglass, with any further spalling being absorbed by the backing to provide the crew with highly effective protection against internal damage.
Slat armour constructed of aluminium alloy for weight reduction is also widely used to protect the rear of the vehicle (the engine block) from damage by shaped charge warheads, but this is an additional unit sold by FOAM and not considered to be a component of Calumnis-3.
Your tanks are an inspiration "tear roles down cheek" 
. But seriously, WOW 
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