“Bash, bash, bash, bash, bash our way to glory…”
Making up the remaining one of every sixteen legions (i.e., one per three light cavalry or heavy infantry, and one per nine light infantry), we have the heavy cavalry. Direct-fire death on very large treads, which is to say, main battle tanks. The biggest of all the big sticks. Putting the “brute” into “brute force”.
For additional flexibility, the majority of Imperial MBTs are built off a common base platform, with a selection of swappable modules to provide specific functionality for specific cases. (Unlike many modular vehicle systems in this ‘verse, however, these aren’t hot-swappable; the need to remove and replace and integrate large and complex chunks of armor plate, etc., when doing it means that this requires some pretty major machine-shop type facilities. It’s not something you can do in the field.) Due to these functionality differences, MBTs are usually classified by the module.
So first we’ll talk about the capabilities of the base platform, and then we’ll talk about some of the more commonly seen modules:
Base Platform: Armor
The armor of Imperial MBTs is relatively standard: there’s just a lot of it. A honeycomb-patterned diamondoid-composite structural frame, covered with multiple slabs of interlinked refractory cerametal, electrical and thermal superconductor meshes, more cerametal, reactive-armor sections, and an outer anti-energetic ablative coating sprayed on top of it all, with additional side plating to shield the rollagons (see below), and an inbuilt nanopaste-based self-repair system. The survivability specifications on all this armor is that the vehicle should be able to survive a near-miss with a tactical-range nuclear weapon or equivalent orbital k-kill strike.
The entire vehicle is itself low-slung, to minimize its target profile, and keep the center of gravity low. Much like the heavy infantry, though, they don’t bother with significant chameleonic or stealth features, since there is absolutely no way to render one remotely stealthy.
Base Platform: Command and Control
An Imperial MBT nominally crews three: semi-specialized commander, driver, and gunner positions; of course, this is a mite fuzzy inasmuch as they’re both ably assisted by the vehicle’s internal synnoetic AI, and indeed linked to each other and the AI by internal conflux hardware, functioning as a loose, mesh-topology group mind for maximal efficiency. Primary control is routed through the AI and direct neural links – the vehicle seats are virtuality chairs, connecting to the crew’s implanted laser-ports – but auxiliary/backup manual controls are also available.
Core sensors and communications include all the standard options: radio and whisker laser communications, access to the OTP-encrypted military mesh, threat identification systems, teamware and C3I systems integration, thermal imaging, remote sensor access, 360 degree sensing, pulsed-usage radar and lidar, T-ray high frequency snoopers, ground-penetrating radar, target-painter detection – and, of course, plain old electronic visual and sound transmission, since the interior of the MBT is fully sealed and includes no portholes.
The MBT also includes a major-node-grade battle computer, and a full ECM suite.
Base Platform: Internal Environment
To the delight of those legionaries who like a little comfort in their soldiering, the internal spaces of an Imperial MBT are a comfortable – albeit confined – shirt-sleeve operating environment. (With climate control! And leather seats!)
This is partly because given the expense of building one of these things anyway, throwing in a few civilized comforts is barely a blip on the budget, and partly because – well, anything that successfully penetrates the armor tends to leave the crew as a hundred-yard long red/blue/silver-white/etc. (delete as applicable) smear on the ground behind the exit hole anyway, so there’s not much point in having them sit around in full combat gear.
This is also fully sealed and environment-controlled for NBCN protection and exotic atmosphere/vacuum use. It also renders all tanks amphibious tanks by default: once you’ve covered all the various atmospheres and pressures you might need to operate in, and obviously discarded air-breathing engines, you’ve built a vehicle that can shrug off submergence, too. You could drive a modern Imperial MBT from continent to continent across the ocean floor, given a case of rat bars and a good reason to try it.
Base Platform: Loadout
The base platform loadout includes a pair of bilateral cheek-mounted ortillery target designators, heavy mass-drivers, and slugguns/micromissile launchers at the front, on either side of the module mount and the armored prow (used for ramming/demolition), and a pair of rear-facing cheek-mounted medium mass-drivers at the rear for local defense. Completing the mix, a center-top-mounted “backscratcher” (a projector for downward-firing flechette shells) permits the vehicle to rid itself of pesky close-in infantry.
(Along with, of course, full-coverage point-defense lasers and autocannon, independently and automatically targeting all incoming fire.)
At the far rear of the tank, an externally-opening compartment can be used to hold resupply, infantry needing transport, or a thermal-thruster fuel pod to increase vehicle endurance.
Base Platform: Power
It seems a little inappropriate to say that the MBT is also powered by a micro-fission “hot soup” reactor, inasmuch as, well, it ain’t that micro. It is “mini”, perhaps, compared to standard-sized fission reactors, but it’s as large as the thorium molten-salt kind gets. The bigger ones all tend to be the safer “pebble-bed” design.
Naturally, this is buffered through a large set of superconducting-loop accumulators to handle immediate power draws and provide backup power in the event that you lose the power reactor – enough to withdraw, anyway, although probably not enough to fight with.
Base Platform: Propulsion
The Imperial MBT moves on neither wheels nor treads; rather, it sits atop eight semi-squishy rollagons, near-spheres rotated electromagnetically from within the sealed main hull, enabling it to move with equal facility in any direction, at speeds of up to 150 mph. The propulsion system also has considerable electromagnetic control over the shape of the rollagons; while they don’t have them normally, if you need spiked wheels or some other shape-variation to cross some tricky terrain, it can provide them on demand.
The base tank platform also includes a limited – by power availability and overheating, given the high mass of the vehicle – vector-control/nuclear-thermal thruster flight capability. This is typically used for skipping over tank traps, scaling vertical obstacles, and short ground skims, as well as being used in reverse to keep the vehicle on the ground with sufficient ground-pressure for the rollagons in low-gravity environments; since the vehicle has the approximate maneuverability of a lead brick in the air, it is strongly advised not to try to use it for anything more, lest you suffer from a fatal encounter with a real aircraft.
It does, however, greatly ease deployment from transport aircraft or shuttles, when used, since it lets you kick the tank out the back of the aircraft and ride their vectors safely to the ground.
And now, the modules:
Modules: Tactical Assault Tank (HV-10 Basher-class)
As close as it comes to a “standard” MBT design, the HV-10 Basher-class module loadout is similar to the V40 Ralihú IFV, scaled up; the Basher-class comes with a turreted heavy mass driver, but substitutes dual independently turreted quadbarrels for the Ralihú’s coaxial quadbarrel. (The heavy mass driver is also designed to function as a heavy sluggun, if required, and as such is entirely capable of delivering large-diameter canister shot for anti-infantry work.)
Modules: Long-Range Assault Tank (HV-12 Stormfall-class; also HV-12i Longeye-class)
The HV-12 Stormfall-class LRAT module is equipped with a super-heavy mass driver intended to be capable of long-range indirect as well as direct fire, and bilateral missile pods on either side of it, each capable of doing a simultaneous launch of up to 16 minimissiles with a short cycle time from internal magazines. Just perfect for those days when you want to fight in the shade.
By changing the missile loadout of the Stormfall, it can also serve as an active air-defense platform.
Rarely seen is the HV-12i Longeye variant, which trades in both super-heavy mass driver and missile pods for a graser installation, suitable for direct fire only but capable of punching out even more heavily protected targets. Also, notably, the Longeye graser is often capable of penetrating the atmosphere and reaching targets in low planetary orbit.
Modules: Drone Tank (HVC-14h Thunderbolt-class; also HVC-14l Stinger-class)
A drone tank, in legionary parlance, is the land-based miniature equivalent of an aircraft carrier. The HVC-14h Thunderbolt module contains nanoslurry and miniature drone components, which it uses to construct and deploy ad-hoc micro-AKVs to suit the requirements of the current battlespace, launching them into action as a centrally coordinated wing, for defense, reconnaissance, attack, or other functions.
The HVC-14l Stinger functions similarly, but substitutes swarm hives for the micro-AKV factory, and is thus able to saturate the local battlespace with microbot/nanobot swarms, be they the standard eyeballs, shrikes, gremlins, or balefire, or more specialized models.
Modules: Tactical Arsonier (HV-10a Flammifer-class)
Used for area denial, reducing bunkers and dug-outs, and to clean up nanoswarms, the Flammifer-class replaces the heavy mass driver of the Basher-class with a scaled-up nuclear-thermal flamer, while retaining the quadbarrels as-is.
Modules: Command Tank (HV-10c Strategos-class)
The Strategos-class is a specialized vehicle for coordinating tank-squadron activities and close air support. The Strategos module doesn’t add any weapons systems; rather, it adds two more crew positions for squadron command, a specialized tactical/logistics C3I AI, and a nodal communications suite and its antennae.
A pair or triplet of Strategoi are usually assigned to a tank squadron made up of other classes for command/control functions.
Modules: Pummel (HV-11 Pugnacious-class)
The pummel tank is a highly specialized variant, designed to rip apart buildings and fortifications. It carries sappers in its rear compartment, and is equipped with specialized demolitions equipment up front.
Modules: Wrecker (HV-10w Trison-class)
Another highly specialized variant, the HV-10w Trison and other wreckers are logistics units, used to recover wrecked tanks and other heavy equipment off the battlefield for repair or for scrap.
As with all other units of the Imperial Legions, the heavy cavalry too has its drone accompaniments, with each MBT usually having a pair of WMH-12 Skyorca drones attached to it for close air support, along with a pair of heavy ground drones matching its own tactical function.
The Flapjacks were made for this. Apart from that, they mostly drive to wherever they’re going, because only the biggest transport aircraft can manage to carry them.