MRA-550 Lion in testing.
MRA-550 Lion Self Propelled Gun
Key Data
Crew: 3
Dimensions
Length (not including gun): 7 m
Height: 3.2m
Width: 3.2 m
Weight: 61 tonnes.
Ground Clearance: Variable. Default at 48cm
Performance
Maximum (Governed) Speed: 91 kph/98 kph
Cross Country Speed: 67 kph
Speed, 10% Slope: 40 kph
Speed, 60% slope: 20 kph
Acceleration: 0kph to 32 kph in 4.9 seconds
Range: 600km (internal fuel tank)
Armament
Main Armament: LAMA HAP1 155mm 55 calibre, high-pressure ETC ERFB rapid firing gun-howitzer
Commander's Weapon: MA-300 Berdun
Power
Propulsion: 15L LY697 1,600 HP (1,200 kW) hybrid-electric opposing-piston multi-fuel hyperbar engine (MRA-550)
Transmission: Hydropneumatic automatic transmission (5 fwd gears, 2 rvse)
Power-to-Weight Ratio: 37.8 hp/ton.
APU: 2 (underarmour)
Armour and Protection
Armour: Advanced Titanium Composite, ‘Hauberk' ERA.
Anti-Spalling: Dyneema/Resilin
NBC Protection: SCFM, clean cooled air, LYMkII CBRN overpressure system.
Missile Countermeasures: GOLIATH/SACHERI Active Protection System, LA-16 FFR
History
The LY7/366 was the main self propelled gun of the Theocracy since its debut, the overall effectiveness of which was never doubted. However, advances in technology both electronically and in guns made the weaponry possibilities too tempting to ignore. Covenant Arms decided to start a new Self Propelled Gun project for the future of the Theocracy's artillery forces. The development of the LY8/HAT-III happened alongside the development of the new SPG, and the new main battle tank was designed in order to be modified in such a manner. This is in stark contrast to the LY4A2, and proved to make the adoption of a new howitzer alongside the new tank a logical step logistically. The MRA-550 Lion passed all milestones on time and after a trial by fire in Natrona County, was adopted widely.
Armament
The MRA-550 Lion's main goal is to provide accurate, powerful, and swift artillery strikes from great range. It is not supposed to be an all-combat scenario vehicle that is meant to participate in frontline combat, nor is it supposed to be able to handle. Localized counterattacks on its own. As such, the MRA-550 is a break in standard Covenant Arms design philosophy as it does not feature any heavy machine guns, grenade launchers, missiles, or autocannons with which to defend itself from vehicles or infantry. Defense of the battery has been left in the able hands of other vehicles and systems while the design focus of the Lion has been entirely placed on the main gun.
The gun of the Lion is the LAMA HAP1 155mm 55 calibre, high-pressure ETC Extended Range Full Bore rapid firing gun-howitzer. It is 8.5 meters long and comes with a 700mm recoil mechanism, an outsized example for a gun this size. The wedge-type breech block is integrated with an exchangeable primer magazine fitted with a standard conveyer assembly for automatic (but adjustable and controllable) primer transportation, loading and unloading.
Also in keeping with other developmental and lethality standards, the HAP utilises an electro-thermal chemical propellant ignition system. As is the convention, an adaptive plasma-based flashboard large area emitter (FLARE), was selected as the implementation method of choice, for both lethality (paramount) and ongoing standardisation.
The Lyro-Lamonian-Marshite ‘Theophilus Omega’ based upon the Compact Automatic Loader designed by Meggit Defense Systems, Inc, of Irvine, California and the previous 'Theophilus”. The Meggit system, ground-breaking at the time, included a fully articulated robotic transfer unit, which could support a load rate of 12rpm, and boasted a magazine access rate of 15rpm.
Theophilus Alpha is very similar to the Meggit design, although rather than making 34 rounds available, the system (due to the larger diameter of the LAMA HAP's 155mm rounds) only allows for 24 rounds. As it happens, this has served to accelerate the loading process, even as ammunition available has come down, allowing for burst fire rates of 33 rounds per minute (for about 10 seconds), and sustained fire rates of 24 rounds per minute. This is partly due to the Meggit design, being as it was intended to slide into an M1 Abrams without impinging upon crew space, presuming the requirement for a loader and gunner in the turret. Theophilus Alpha, bereft of such requirements in the Lion (as with the Dire Wolf, which also operates the same loading system), utilises two such-units, thus allowing 48 rounds in total, and allowing for slightly differing layouts to optimise performance. Each sub-unit uses a double-row closed-loop chain of canisters, granting the magazine excellent volumetric storage efficiency. When the gunner selects an ammunition type (using his switch on the control yoke), the nominated round is moved to the blast port by the carousel, whereupon a ram-arm pushes it into the chamber.
Removal of a loaded round is essentially the same process, in reverse, although using a tri-forked extractor, rather than a ram. Theophilus features a full automatic ammunition inventory, and grants very high load speeds, coupled with an exceptional reliability, due to its relatively simple operation. A unique system of operations allows six rounds to be linked through the autoloader, providing six rounds in eight seconds. It should be noted that while this is possible, the depletion of ammunition in such a mode skyrockets, and the time between shots from the six to the seventh almost triples before the Lion gets back to its standard rate of fire.
The HAP's inner walls are 300ksi aged martensitic titanium alloy with tungsten carbide facing 4.7" thick, weighing 2,300kg, and yielding a very high reserve tolerance for the medium-to-high-pressure rounds the HAP is optimised to fire, and, in fact, possessing a 20% reserve tolerance for the rounds that the higher pressure predecessor system was intended to throw. As with that, this is strengthened by wire-winding the barrel using ultrahigh-modulus carbon fibre, rated at 550GPa. The HAP uses 750 kg of a NS$7.2m-a-ton material wound at strategic points along the barrel, for a total cost of NS$5.4m.
Around the carbon-fibre wrapped inner barrel is a titanium tensioning sleeve, tapering towards the muzzle end. The titanium sleeve is fitted to the inner barrel at the chamber and by means of a vibration-dampening stiffened disk, giving the gun the same properties of a full-thickness barrel over the whole length, while saving considerable weight, and shielding the carbon fiber from environmental effects.
Thermal management in the HAP is extensive, with a suite of features. The primary is a bank of heat sensors installed between the tensioning sleeve and inner barrel. This sensor bank records ambient temperature, and ensures that safe parameters are maintained. Should higher than normal rates of fire generate unexpectedly high heat generation within the main gun, the subsequent counter-thermal measures come into play. First of these is a simple sprinkler system within the tensioning sleeve, designed to spray water into the space between the barrel and sleeve, in order to rapidly bring down otherwise concerning temperatures. A series of small perforations along the exterior of the thermal sleeve allow this steam to escape, aided by similar (albeit considerably smaller) perforations in the support disk towards the muzzle.
The range using standard munitions is 50 kilometers, with guided long range rocket ammunition reaching as far as 70 kilometers downrange. The HAP can fire any 155mm ammunition in existence or development, from APFSDS LY29, mines, thermobaric, HEAT, flechette, smoke, and canister to nuclear, biological, and chemical rounds. The Lion can be serviced by a Buckler gun truck in under five minutes.
The Lion also uses a single MA-300 Berdun light machine gun for light anti-personnel defense, giving it the ability to engage and defeat armored infantry in the immediate vicinity.
Propulsion and Mobility
The MRA-550 does not share the modularity of the LY7 family, but for ease of repair and maintenance, features the easy-access armoured engine bay, electric transmission (wherein the drive shafts are replaced by cable, and power from the engines transferred by that cable – with attendant volumetric, fuel consumption, acoustic signature and lifecycle-cost benefits)
The vehicle’s hydropneumatic suspension enables it to ‘sit’ or ‘kneel’, a factor which notably increases the elevation and depression arcs of the Doberman’s main gun in defensive roles, and makes up for the platform’s low-profile. As with the LY8, and indeed with nearly every Lyran AFV since the LY219, the suspension is separated from the hull, mounted on the underframe, rather than the side frames. This, when coupled with the Lyran-standard extensive acoustic dampening in the semi-synthetic anciniform spidersilk spall liner, reduces the internal noise to 60db, an improvement of nearly 5% on the LY8 thanks to the lower volume needed.
The final-drive power-transfer cross-shaft is retained from the original, providing greater power efficiency in turning maneuvers by transferring the power regenerated at the inner track during a turn to the outer track.
Cromwell or SACHERI system oversight of any engine fitted monitors each segment, and monitors and records stresses and damage, and also keeps a log. This log is periodically passed back to unit maintenance units, and can be downloaded, or accessed by crew upon command-entered request. This factor contributes to reduced attrition, enhanced combat readiness, and considerably eased maintenance workload.
The vehicle’s exhaust is released from several locations along the vehicle’s underside, somewhat obscuring the vehicle’s thermal signature by providing a fuzzy area of increased temperature, rather than a single hot point.
The entire assembly is, as per the extant norms for Lyran and Covenant-aligned AFVs, fitted with deployable sand filters for use in high-sand environments, such as deserts or certain parts of the littoral.
Digital rear-vision cameras also come as standard, allowing for considerably less and more timely reversing of the vehicle.
Tracks are shrouded as standard to increase resilience to battle damage, and have seven road wheels and two drive rollers, with only the forward roller on each side partially unshrouded.
Tracks are, in turn, provided with resilin padding by default, which serves to lower their acoustic footprint. The resilin itself never lasts as long as the tracks themselves do, but they’re handy to have while they are around, provide excellent traction, lower damage on the terrain over which the vehicle drives, and lowers the platform's acoustic signature. Wear-and-tear or loss of the resilin padding will not negatively affect the tracks themselves in any appreciable manner.
On Lyran and Covenant vehicles, the engine of choice is the purpose-built LY695, a slightly smaller and lighter variant of the LY693 fielded in the LY4A2 Wolfhound, LY224 Sorcha and LY9/M22 Dire Wolf.
The 15L LY697 1,600 HP engine, which is compact, powerful, fuel efficient and quiet, although a little more time consuming on the maintenance than a more conventional engine of equivalent power. The time-in-maintenance issue is considerably mitigated by the Cromwell or SACHERI backed engine diagnostic, which takes a good deal of the guesswork out of the process of maintenance and repair. It is roughly analogous to the LY7A1's engine, the -693, but made with superior titanium alloy in place of steel for a lighter weight. This is the same engine as powers the LY8. It was decided to retain it.
The result is that while top speed is lower in a governed sense in order to ensure stability with the howitzer, it is beyond exceptionally speedy and agile for a self-propelled gun. It features world-benchmark setting acceleration and handling, allowing it to fire and move. In testing, the Lion is capable of getting several full barrages off without counter fire as the enemy's inability to capably track the Lion renders even highly effective artillery batteries grossly outmatched.
Networking, integration, electronics and fire control
Battlespace-networking and the use of information and electronic warfare as a means of force multiplication has long been a staple of Lyran and Covenant design philosophy. Indeed, first-flight LY8s were themselves a new benchmark in this regard, and the implementation of their unique helmet-mounted targeting interface, while having more than a few teething problems, served to appreciably improve crew awareness and engagement speeds. The MRA-550, like the LY8, is fitted with a highly extensive sensor suite so as to enable the transmission of as much information as possible into any extant battlenet, while possessing substantial internal (multiple-redundant) computational facilities so as to handle required downloads from that selfsame network.
As with all serving and planned AFVs, the MRA-550 is designed to utilise the Cromwell II battlespace architecture and the roughly analogous SACHERI for Covenant use. Cromwell II and SACHERI is an integrated and adaptive battlespace network that maximises combat lethality, performance, and output and enables command and control on an unprecedented scale. Information is sourced not only from multiple sources on the individual platform, but from every Cromwell II and SACHERI equipped friendly vehicle within the battlespace, which provides constant informational updates across a broad spectrum of sources, both known to the operators and (more significantly) operating below their awareness. With the LY4A2 and LY224, the Cromwell II and SACHERI system began to mature as a force-multiplier, with effectiveness of the system increasingly and exponentially evident to all but the most entrenched detractors. Image and pattern recognition software constantly interfaces with sensory systems (even while the given input is not being examined by crew, a means of avoiding the ever-present threat of data-overload), and the results both relayed to friendly and superior force elements, and also displayed for action by the vehicle operators.
At the most basic level, the Cromwell II and SACHERI system aims to accelerate engagement cycles and increase operational tempo at all levels of the warfighting system. This acceleration is achieved by providing a mechanism to rapidly gather and distribute targeting information, and rapidly issue directives. Cromwell II and SACHERI's ultra-high speed networking permits almost completely error-free, high integrity transmission in a bare fraction of the time required for voice-based transmission, and permits transfer of a wide range of data formats, from a multitude of compatible sources.
Borrowing from fire control measures designed by the Koreans for the K2 Black Panther, and implemented in a host of Lyran and Covenant AFVs, Lyran Arms developed a built-in trigger-delay mechanism. Most earlier platforms can be found to, despite all other fire control methods, miss their target when they fire their gun/s and hit a slight bump at the same time, a problem exacerbated, as would be expected, by movement at high speeds and/or across uneven terrain. The designers of the K2 anticipated this situation, and generated a solution for it by installing a laser emitter-receiver assembly linked to the FCS, a concept that was brought across for implementation in the main gun on the LY7A1s, and is now commonplace on Lyran weapons.
The emitter is fitted near the top of the barrel, with the receiver being placed at the barrel's base. The weapon can only be fired when the laser receiver array is exactly aligned with the emitted laser. To illustrate, if at the point of firing, when the gunner presses the trigger, linked as it is to the fire control system, the vehicle comes upon an irregularity in the terrain at the same moment, the laser will find itself pushed off the receiver by the sudden movement, and the FCS will delay the round's ignition until the beam reorients to the receiver again. As the barrel shakes up and down, the FCS will automatically fire off the gun when the laser finds its mark, and the barrel is judged to be on target. This system, combined with an advanced gyro-stabiliser, static pendulum cant-sensor and powerful fire control system, dramatically improves the vehicle's capacity to engage targets while moving at speed, even across broken terrain. For the MRA-550, this enables brutally effective on the move indirect fire as this system is modified to work instead to take into account various atmospheric and rotational effects.
In case of an emergency, the vehicle can be operated by only two, or even a single, member of its three crew. The FCS can autonomously locate and track visible targets, comparing them both to known hostiles (identified by way of the Cromwell II and SACHERI datalink) or targets established by image recognition (again as available via information uplink), avoid blue-on-blue engagements and fire its main gun without needing any input from a human operator, although the absence of a human operator will adversely affect engagement tempo.
The MRA-550's crew-stations borrow extensively from more modern Lyran and Covenant norms, and utilise a far more advanced and adaptive control interface than that of legacy platforms. The new system integrates the data gathered by the vehicle's external sensors and projects it directly onto the HUD inside the crew's headset-visor, a feature not dissimilar to that utilised in the BALCOTH helmet. As the operator turns his head, the view pans, and the image displayed can be either a direct projection of the terrain and environs, as would be seen with the naked eye were the tank's hull not in the way, or various overlays, magnification and enhancements that can be applied or superimposed to highlight important elements (such as friendly forces), in a fashion not unlike an aircraft's HUD. From this point, either physical or voice activated controls are then used as required. By way of example, the vehicle commander may look left, with the weapon mounted on the commander's weapon station following his movement (if the function is activated).
With Cromwell II and SACHERI having identified hostile dismounted infantry, the vehicle's commander simply places the targeting reticule (located by default in the centre of his HUD) upon the desired target, and presses the firing stud. Alternatively, he could centre the reticle at a target, and designate it for engagement by the gunner by either voice command or toggle. Targets can be sequenced for engagement, and the gunner may target and fire in a similar manner using the vehicle's main gun, or either of the co-axials. The gunner's station is identical to, and interchangeable with, the commander's, and either can take on additional roles if the situation requires. When used in conjunction with Cromwell II and SACHERI, and the new fast-traversing shielded-electric turret, the engagement speeds of the MRA-550 are 30% as fast again as that of the LY7/366 'Lammasu' Self-propelled Howitzer's legacy system, and nearing double that of most international artillery platforms.
Some issues with platform stability have adjusted the inputs, with the helmet mounted weapon traverse only applying when the operator has his ‘enable’ switch depressed. At other times, the crews’ head movement will simply pan the camera-fed images presented to their helmet displays.
Like the LY8, the MRA-550's computational capabilities are internally disbursed; making use of widely spread individual, multiple-redundant components, connected through the use of solid-core photonic-crystalline fiber-optic cabling. Fibers-optics are used instead of more traditional systems as signals travel along them with less loss and allowing for a higher-than-standard bandwidth, and they are also immune to electromagnetic interference. Photonic-crystalline fiber optics have in turn been selected due to the improved confinement (and thus loss reduction) of the light which forms the data carriage.
Highly magnified imagery of photonic-crystalline fiber optics. Image courtesy of the United States Naval Research Laboratory
While adding to the cost of the (already expensive) electronics, the presence of such a system allows for greater parallelity, system robustness and combat durability than an equivalent unitary system. Combat damage may slow the system, but is unlikely to completely destroy it, without having destroyed the entire vehicle.
Continuing on a trend in Lyran and Covenant hardware that was established by the original LY6, the platform's electrics, more specifically the processors, are composed of Indium Gallium Arsenide (InGaAs), rather than silicon-based semiconductors, rendering the vehicle proof against electromagnetic interference or EMP-based attack, although the InGaAs is itself yet another highly expensive addition. Given the ever increasing utilisation of sophisticated electronic and sensory systems, shielding these systems is, now more than ever, deemed a centre of gravity for the platform's protective systems. It was quickly reasoned that when operating in an environment which may include anti-strategic platforms such as the LY4032 “Rampart”, the chances of the platform encountering high levels of electromagnetic interference goes up dramatically, and the dangers presented by these and similar munitions far outweighs the relatively modest (though expensive in absolute terms) cost of the implementation of InGaAs components.
The immense potential of this as a feature of military system was demonstrated in spectacular fashion during the Stoklomolvi Civil War, when Lyran warships not only saved the lives of countless Stoklomolvi civilians by defending them from nuclear attack on two seperate instances, but also then, in both cases, were able to exploit the massive EMP side-effect the 'Rampart' generates in nuclear defence. The result was a carrier battle group destroyed, to no Lyran loss. While not a land-based example, the lesson has been learned, and indium gallium arsenide is set to stay as a standard feature of Lyran and Covenant electrics for the some time to come.
The MRA-550 mounts (as standard and integral) long-to-medium range fire-finder radar, specifically the Marshite CA-25 multi-function radar system, a further development of the Lamonian LA-16 intended for artillery. The CA-25 radar can be used in all weather conditions and is a J band doppler radar. The exemplary performance of the CA-25, in a wide variety of combatant roles, lead to its being transferred bodily to the LY8, and now, in the same manner, to the MRA-550 The CA-25 radar weighs 43 kg, and has a maximum effective range of 69 km. The CA-25 can detect incoming artillery fire (artillery, rocket, and mortar types), low flying aircraft (fixed wing, helicopters, UAVs), as well as ground vehicles, and troops. The CA-25 can also observe the fall of shot of friendly artillery systems; thus improving their accuracy. In addition, the CA-25 can be (and is) used as the platform’s radar rangefinder. Concerns raised about the drain the multi-use system places on the vehicle’s computational capabilities did not continue past the implementation of the new computer system, given the exceptionally high capacity of the platform’s processing suite. As with the vast majority of active emitters, the CA-26 can be set to 'off' if EMCON is a mission or theatre requirement.
The CA-16 has the following detection ranges in ideal conditions:
Maximum Range: 69 km
Walking soldier: 21 km
Small vehicle, most UAVs, fixed wing aircraft, helicopter: 40 km
Conventional MBTs: 63 km
Artillery/MBT's main gun: 45 km (not including Cromwell II or SACHERI connectivity. When factored in, the system can use the round's trajectory to establish position of initial fire accurate to 10 m at ranges of up to 75 km, despite not, technically, having a solid radar fix on the firing platform.)
The MRA-550 features links and data-ports able to accept the AN/ALQ-281 ‘Tiamat’ EW system, but, by default, only one vehicle per platoon fields it within Lyran and Covenant service.
'Tiamat' recievers and transmitters are situated in pods atop the turret rear, distinguishable by the multitude of panels and aerials. The system, when engaged, is capable of intercepting, automatically processing and jamming received radio frequency signals. The platform’s electronic attack capabilities involve using radiated EM energy to degrade, neutralise or destroy hostile force- or force-support elements. Of particular note is the potency this represents in the operation of ground forces in contested or hostile airspace. Given the mobile, tactical and ground-based nature of the platform, it is likely that most hostile radars encountered will be airborne ground-surveillance radars or AFV-based radar range-finders. A Tiamat-equipped vehicle is therefore perfectly equipped to wage electronic warfare, preventing a useful target lock on friendlies within the hostile radar’s visible horizon.
More than this, however, the system also makes acquisition of useful radar-based information of all forms, including range-finding, highly problematic at best. Acquiring a radar-based sight picture within a 'Tiamat' protected area can be challenging, although as an emitting system, the full capabilities should be used judiciously, lest the high-potency EM signature broadcast the unit's position un-necessarily, and compromise operational security.
'Tiamat' is one of the first EW platforms to use high-end solid-state emitters, coupled with dramatically elevated potential power throughput, and dynamic and pattern-probability frequency agile (PPFA) barrage and spot jamming to render all but the most potent radars ineffective. Further, if the seeking radar is calculated to be capable of burning through the jamming, the system uses precisely timed and Cromwell II and SACHERI-backed broad-spectrum DRFM (Repeater) jamming, to further maximise detection degradation. Multiple platforms can be co-ordinated to provide simultaneous EW if the radar in question is potent.
This capability places Tiamat-equipped platforms at the very top of known NS-AFVs in the active electronic warfare role. The receivers can also be used to detect, identify and locate non-friendly signals, providing ELINT/SIGINT either automatically or manually. When emissions control (EMCON) is required, however, the 'Tiamat' transmitters can be turned off, which thus, as one would expect, cancels the EM broadcasting. Unlike the earlier AN/ALQ-99 series, the 'Tiamat' utilises power generated by the platform to function. Given the very high power output of the MRA-550's hybrid electric hyperbar engines, and the extensive Li+ polymer battery banks, this has not adversely affected performance in any appreciable manner.
As with many AFVs now in Lyran and Covenant service, the MRA-550 includes a telescoping reconnaissance mast, affixed to the rear of the turret. The mast is topped by a sensor bundle and, when extended, enables the platform to remain in cover, and establish or maintain details of its surroundings. This provides a highly useful service, especially when in the van of an advance, or when positioned along a reverse slope, offensively or defensively.
Armor
The MRA-550 takes its cues from multiple armored developments, namely the late LY8 and the newly developed and fielded LY10. While its greatest defense is its indirect nature and speed, the armor capability of the design of the LY8 gives it great survivability.
Despite the platform’s considerable tactical and strategic mobility for a main battle tank, the MRA-550's armor was of primacy. While conceptually borrowing much from the LY10, the Lion seeks to maximise the available protection, while simultaneously ensuring that additional weight beyond the platform’s 58 tonne hard ceiling was not breeched. Such specialist armour requires specialised materials, even some that people don’t normally associate with armour schemes. Given their recent experiences in the field, the Protectorate Research and Development Commission worked in conjunction with Lyran and Covenant Arms – Lamoni, and LAIX Arms, in order to generate the most effective and appropriate armour scheme within the parameters provided. With the production and resources of the Theocracy backing such efforts after the successful implementation of the LY10's armor scheme and the success of HAT-1A2's in the Civil War as a test bed for the MRA-550, the costs of the ensuing titanium alloy were driven down considerably.
The outer hull of the Lion is composed of Ti-10V-2Fe-3Al (aka Ti-10-2-3). This Titanium alloy is normally used on airframes, but offers one of the best mixes of strength vs. toughness. It is a near beta alloy, developed primarily for high-strength applications in the 1241 MPa (180ksi) range. The alloy also possesses the best hot-die forgeability of any commercial titanium alloy, and is suitable for near net-shape forging applications and isothermal forging. Ti-10-2-3 also offers high strength/toughness combinations and is deep-hardenable.
Composition
C
<0.05%
N2 <0.05%
O2 <0.13%
Fe 1.6-2.2%
Al 2.6-3.4%
V 9.0-11.0%
H2 <0.015%
Ti ~ Remainder
Physical Data
Typical
Density g/cm3(lb/cu.in) 4.65 (0.167)
Melting Range °C±15°C (°F) 1649 (3000)
Mean Thermal Exp.Coeff.20-400°C/°C (68-752°F/°F) 9.7x10-6 (5.4)
Beta Transus °C±15°C°(°F) 796 (1465)
Mechanical Data
Minimum Typical
Tensile Strength MPa (ksi) 1241 (180) 1310 (190)
0.2% Proof Stress MPa (ksi) 1104 (160) 1228 (178)
Elastic Modulus GPa (Msi) 103 (15)
Hardness Rockwell C 41
Tensile Strength
0.2% Proof Stress
Elongation over 2 inches
The base armour of the MRA-550 is tightly layered, with each of the three layers of armour composed of differing materials, so as to generate the greatest total degree of survivability against kinetic and high-explosive munitions.
The innermost layer of the armour, closest to the chassis, is composed of panels of titanium spaced armour, with a depleted-uranium mesh embedded between the spacings, adjacent to the innermost sections of the titanium. The dU is utilised as a mesh, rather than as pellets, as the mesh configuration has been shown to better interrupt the passage of plasma jets from EFPs of HE-based AT weapons. The mesh is heavy, but not outside of acceptable parameters, given the weight saved in other areas of the MRA-550’s development.
The second layer is composed of boron-carbide with the whole layer being further encased in another layer of titanium. This is a break from the use of boron-carbide-backed tungsten disulfide (WS2). The titanium alloy in use on the MRA-550 is considerably lighter and stronger than that used on the LY8, increasing the effectiveness of the composite significantly while reducing weight. In a further push to reduce weight, boron-carbide-backed tungsten disulfide (WS2) was chosen not to be used. It weighs three times as much as equivalent boron-carbide while protecting twice as well. The advantages of the new alloy are such that it was deemed the armor of the system roughly comparable in quality to the LY8 already, and the additional weight not worth the additional protection.
The third and outermost layer of the integral armour scheme is composed of titanium-encased boron carbide, a form of composite armour composed of multiple layers of titanium and boron carbide ceramic. The high tensile-strength titanium plates hold the ceramic in position and the ceramic maintains its resistance to shock even when fragmented, as long as it remains held together.
All of the armour panels can be removed in-toto, allowing for easy maintenance and rapid repair of combat damage. Armour panels themselves consist of all three layers as detailed above, and, upon removal, each can be separated out further for repair or replacement.
Fireproof armoured bulkheads separate the crew compartment from the engine bay, which itself forms part of the forward passive protection suite.
Fuel and ammunition are located within armoured sub-compartments with integral anti-spalling layers, and those self-same anti-spalling systems are also used to protect the internals of the crew compartment. The spall lining is also designed to provide a high degree of noise and thermal insulation, making the MRA-550, in keeping with established Covenant norms, extremely quiet internally analogous (to the operators), to a civilian vehicle.
'Hauberk' shaped-charged explosive reactive armour is fitted as standard (though can be removed) to the turret and major hull areas, on the frontal and side arcs, designed to destroy (or at the very least severely degrade) hostile munitions, be they HE-based or kinetic penetrators.
Owing considerably to its 'Rainmaker' ancestor, 'Hauberk' differs from 'Rainmaker' in two ways. The first change is a shift in the formation of the explosively formed penetrators of the defensive system, from directly opposing the projectile (firing along the same axis as the most likely threat at any given armour location) to a slanted system, angling (approximately) 45degrees up. The new system not only leaves 'Hauberk' considerably more compact, but dramatically improves its effectiveness against kinetic munitions of all forms.
The 'Hauberk' HERA system is composed of “bricks” making each “brick” easily replaceable once used and allowing the system to be fitted to AFVs already in service. The “bricks” are lightweight (at around 3kg) and this allows them to be positioned on as many areas of the tank as needs require. These are not only positioned on the frontal glacis and turret front and sides, but also on the sides of the vehicle, thus providing a very high degree of protection, even against threats originating from outside the frontal arc.
Finally, the MRA-550's unmanned turret roof, like the LY8, is fitted with ‘Acerbitas’ non-explosive reactive armor (NERA) bricks. These thick bricks grant the tank multiple-hit survivability against threats such as explosively formed penetrators, and thus is the most effective lightweight solution that can be provided to an area not conducive to HERA employment.
'Acerbitas' a proprietary NERA developed for AFV protection, and utilising not only the world-benchmark Lyran semi-synthetic anciniform spider silk, but further Lamonian innovations in the form of extruded para-organic resilin. Marshite farming of several species of special spider breeds made available greater quantities. Resilin is an elastomeric fibrous compound found within the musculature of insects. To quote Dr Chris Elvin of Australia's Commonwealth Scientific and Industrial Research Organisation;
“Resilin has evolved over hundreds of millions of years in insects into the most efficient elastic protein known...”
Using genetically modified E.Coli bacteria, the CSIRO team was able to synthetically generate a soluble resilin protein, based upon the cloning and expression of the first exon of the Drosophila CG15920 gene. By means of a CSIRO-patented process, the resulting resilin rubber was shown to have structurally near-perfect resilience, with a 97 percent post-stress recovery. The next-nearest competitors are synthetic polybutadiene ‘superball’ high resilience rubber (80 per cent) and elastin (90 per cent). The cross-linking process itself is remarkably simple. It needs only three components - the protein, generally lactose, or a near analog, a metal ligand complex, ruthenium in this case, and an electron acceptor. The mixture is then flashed with visible light of 452 nanometres wavelength to form the polymer - within 20 seconds, the proteins will be cross-linked into a matrix with remarkable tensile strength.
The 'Acerbitas' armour itself consists of an external plate of titanium, with the filler composed of resilin, with an anciniform spidersilk central mesh. The design is intended, as with NERA generally, to warp, bend or bulge upon impact. As the plates move, LRPs are subjected to transverse and shear forces, diminishing their penetration, and shaped-charge weapons find their plasma jets unable to readily focus on a single area of armour. In the case of segmented LRPs, the transverse forces are less pronounced, compared to unitary variants, but the movement of the plate essentially forces the projectile to penetrate twice, again lowering total impact upon the platform protected. The extremely high recovery rate of the resilin, coupled with its extraordinary energy retention, is aided by the very high tensile strength and hysteretic properties of the spider silk. 'Acerbitas' blocks are fitted over most areas of the vehicle, particularly those for which the explosive-reactive elements of the 'Hauberk' suite are not suitable.
Internal spalling layers are, by default, the now-Lyran and Covenant standard semi-synthetic anciniform spider silk. Despite their unusual origins, once threads are manufactured, the silk is woven in the same manner as fibrous material anywhere. The fibres mesh well, and fibrous internal friction is low while elasticity and tensile strength both remain very high, allowing for exceptionally good resistance, particularly so when compared to other similar substances, such as aramids. The fibres, unusually, become proportionally stronger as they get thinner, and research and implementation quickly established what spiders established millions of years ago, that weaving 100 thin fibres into a silken strand is almost 60% stronger than an equivalent width single strand, while utilising (approximately) only 80% of the material mass. Also, critically, spider silk has a biphasic modulus – when initially subjected to force it is very stiff, like kevlar, but just before the yield point it becomes very elastic. It also undergoes hysteresis, so if released from tension it comes back into shape, making, as a result, an extremely durable material.
Further, while offering slightly improved protection-to-weight ratios than kevlar, anciniform spider silk is dramatically thinner, allowing notably more material to be packed into the same space. As a consequence, while the protection per unit weight may be similar to kevlar, the protection per unit volume is considerably higher, and it is this consideration that lead to its adoption as anti-spalling on most Lyran and Covenant vehicles, at the cost of an additional 400kg of weight. Again, this option is modular, and some formations do not utilise it.
Additional considerations of protection have led to the track skirting being well armoured. Structurally titanium, the individual segments themselves are layered similarly to the 'Acerbitas' NERA, with resilin fitted between titanium front- and back-plate armour panels. Given the semi-fixed nature of skirting, generally, this adds considerable movement in the event of impact, consequently spoiling much of a penetrator's effect, including its behind armour damage (BAD). The MRA-550 foregoes additional armor under the vehicle, a change in design philosophy owing to the relative rarity of Lyran and Covenant battlespace linked vehicles becoming victims of mine attacks. The weight loss was considered a net positive.
Signature Reduction
Signature reduction is not considered a primary element of a Self-Propelled Gun's defense. However, solid signature reduction has become a standard element across both Lyran and Covenant Arms.
The LY8 represented a tremendous decrease in the observability characteristics of AFVs. Detection ranges for stationary LY7s were 15% that of LY4A1s, and still lower in relation to most competing non-Lyran and Covenant platforms. The LY4A2 continued on this pattern, and when even the behemoth LY6A1 had a smaller detection footprint than most non-Lyran and Covenant AFVs (despite their being barely 60% of the LY6's weight), the success of the signature reduction measures was put beyond doubt. The LY9 pushed the envelope still further, and put the Dire Wolf in a position of tremendous strength when dealing with hostile forces. The MRA-550, built subsequently to the LY8, utilises the same technologies, but on a considerably lighter platform, producing a vehicle that has taken signature reduction methods to what is arguably a new benchmark, whether the detection methodology is radar, infra-red, direct LoS, magnetic or acoustic in nature.
The first method by which the detection signature is reduced is through use of the Lyran-designed and manufactured 'Warshroud' advanced multi-spectral camouflage netting system. Based heavily on the Ukrainian 'Kontrast', 'Warshroud' dramatically reduces the detection ranges against known radar, infra-red and visible-band methods.
High-precision, high-lethality systems universally require integration with means of detection, which of necessity requires the design of sensor sets and target locators, and the implementation of effective scanning capabilities across several adjacent or near-adjacent visible and invisible spectra, including visible light, close and long infra-red waves, and laser scans(in the infrared, millimeter and centimeter wave bands).
Kontrast took an ordinary camouflage net as the base and, utilising the latest technological innovations, turned it into a new generation signature-reduction product to combat the sophistication of modern radar systems and other contemporary military reconnaissance means. The result was the development of a surprisingly effective solution.
Developed countries traditionally have utilised a wide variety of signature reduction technologies, many of which include various after-manufacture coatings. The technical requirements of such coating are very high - their reflection capacity must be below 20 dB in a wide range of bands. This factor forced the Ukrainian – and later Lyran/Covenant – research teams to examine new physical methods for reducing or amplifying reflection of radar waves to achieve effective electromagnetic concealment. With this goal in mind, the 'Kontrast' developers tried to find materials with absorptive and reflective characteristics for attenuating and amplifying electromagnetic waves. Experiments generated a series of composite materials with superb characteristics for greatly diminishing the wave reflection contrast between the protected object and its background.
'Kontrast' simultaneously employed both absorption and targeted reflection of electromagnetic waves. The array of material used within the netting the product, each of which featured at least one of the said qualities, allowed protection from a great range of known target location means. 'Kontrast' tests have repeatedly shown its superiority across a wide range of battlefield conditions to analogues from Sweden and Britain, whether the concealed unit is moving or stationary.
'Warshroud' built on 'Kontrast' by the integration of signature reduction techniques in the IR spectrum pioneered by the LDPCU multi-spectral camouflage. The resultant product takes nearly twice as long to produce, due to the difficulty in applying a coating (which had been done away with under 'Kontrast') to the camouflage netting. Attempts are being made to shorten the 'Warshroud' manufacturing process, but it is somewhat of a moot point. Production as it stands is more than capable of keeping up with the manufacture of the vehicles utilising 'Warshroud'. The system's visible suppression includes, as with most camouflage nets, terrain-appropriate textile strips, which are soaked in a dielectric polymer that can absorb and scatter electromagnetic waves. The textile pieces are made of non-reactive, radar transparent fabric. 'Warshroud II', the successor to the original 'Warshroud', differs only slightly, with semi-synthetic anciniform spidersilk being interwoven into the textile strips, providing considerably higher durability in all conditions. For the LY8, and now also for the MRA-550, 'Warshroud III' is utilised, featuring spidersilk not only for the interweave, but also for the netting upon which the textile strips are attached. This has been selected to ensure optimum service life for the shroud, and reduce the incidence of reduced signature reduction due to environmental ablation.
In 2002, tests run using 'Kontrast' on a T-84 determined that the ability of hostile weapons to lock onto a vehicle dropped a remarkable nine-fold compared to an unshrouded vehicle. It was further established that T-84 MBTs fielding 'Kontrast' dropped out of visibility range of viewing devices at distances over and including 500m.
'Warshroud', and its 'Warshroud II and -III' descendants built on this performance, with additional substantial reduction in detectability of targets in infra-red, radio-thermal and radio wave bands. Improvements in synthetic and parasynthetic textiles have also reduced the inherent radar return in the material which binds the net together, along all detection envelopes.
'Warshroud' has repeatedly demonstrated excellent resistance to various external factors while keeping its camouflaging characteristics intact – a factor very quickly determined to be a critical capability of the system. Tests had tanks equipped with a 'Warshroud' run at their tops speeds in off-road conditions, in woods and deserts, while similarly equipped IFVs conducted amphibious landings. In all cases, the signature reduction capabilities of the equipment were unreduced to any appreciable degree. All elements of 'Warshroud' are resistant to fuels, lubricants (gasoline, diesel fuel, lube oil) and detergents. Furthermore, spinning off from research conducted into the LDPCU once again, the shroud is made of self-extinguishing materials, ensuring that flames cease to burn free of subsequent glowing, once the fire source is removed.
'Warshroud' itself consists of a number of modular components that can be put together to create a masking surface of any size and shape, with colours matching any field environment in any season.
The second primary means of signature reduction is focused on the engine and drive systems of the tank. While already alluded to above in the analysis of the platform's propulsion and mobility, relevant points will be reiterated here for ease of reference.
The vehicle's electric drive differs from conventional AFV drive system arrangements by utilising a hybrid power-plant. This essentially means that the engine generates electric power which in turn powers the batteries which propel the vehicle. The electric drive, has, importantly, implemented a suite of features designed to mitigate its detectability, both acoustically and thermally. As with the LY8, the MRA-550 has improved on the all previous performance in this regard, by providing the same acoustic insulation in the specially designed engine bay, and by doing so on an engine that is smaller than that of the appreciably-heavier LY8.
As with a number of earlier marks of AFV, the decoupled suspension is separated from the hull, and similarly separated from the final section which turns the drive wheels, a factor which considerably lowers audibility in itself.
Acoustically, the MRA-550 uses the LY8’s benchmark in low observability, due to the utilisation of the ultra-quiet engine and engine bay. The hyperbar's intrinsically lower acoustic signature was a consideration in its selection, and makes the 61 tonne LY8 exceptionally quiet. The 20-ton-lighter MRA-550 is, as one would expect, even more so. By utilising the Cromwell or SACHERI system to actively monitor the engine and propulsion systems, the crew is able to remain constantly aware of the amount of noise being generated, and also the amount of heat being radiated.
As a result, the MRA-550 is expected to be able to boast a best-in-class detection footprint, whether in IR/thermal, radar, acoustic or visual. While not a primary method of defense, when combined with its speed and the long range, accurate nature of its firepower, the MRA-550 is the most survivable self-propelled gun ever made.
Crew amenities
It has been a well-known fact in most militaries that well-rested and alert soldiers with a high morale and a high degree of confidence in themselves and their equipment will perform faster, more effectively and with fewer avoidable errors than those who fall short in any of the above categories. To that end, Covenant vehicles have put a strong emphasis on designing and manufacturing hardware that can effectively cater for the comfort needs of personnel that fight from that hardware.
The Lion fields the commonplace hot and cold water drink point, which provides hot water, cold water, and with two further compartments that can be filled with hot or cold drinks of the crew or unit's choice. As well as being morale boosting, hot water in particular can be of direct military value, with it being used to brew tea or coffee, produce other hot beverages and, most importantly, it is used for dehydrated ration packs common to many armies and armed services.
Situated immediately below the drink point is a small bar fridge, which can either carry spare rations, 'jack' rations, or approximately two cases of soft-drinks or equivalent.
The NBC system follows Lyran and Covenant standard, and features quite adequately as a climate control system, making for working temperatures easily adjustable to every national or personal need (operating temperature range -40C to 55C). The MRA-550 Lion represents an upgrade in capability, in this regard, as each crew member is now able to control the operating temperatures of their own console area with less power drain, individually.
Export
The MRA-550 Lion is a potent Self Proppelled Gun with advanced anti-detection capabilities and world-class mobility and accuracy. Combined with its ability to fire quickly and lay down withering fire for long periods of time, the Lion is a perfect solution to any problem that needs an SPG to solve it.
The MRA-550 Lion costs $9 million standard NS dollars. DPRs are available at $9 billion.
Sales are made through Covenant Arms.
