XM520 “Bolo”
I built the dang thing, and it scares me. (…) First time it hit me: I wonder what it's thinking about. Kind of scares me to think about a thing that big with that kind of armor and all them repeaters and Hellbores and them computers and a quarter-sun fission plant in her—planning what to do next.
-Field Test
Reducing crew requirement can make a tank smaller and lighter, improving its survivability.
Or, it can make a tank tougher and more heavily armed.
And smarter.
Crew Composition[]
- Commander—sits in an AMAP-MPS seat to absorb the shock energy of a blast.
Although it doesn't quite count as “crew”, the vehicle's AI is a crucial part of the XM520's operations. Is encased in its own shock-absorbent protective cocoon.
Sensory[]
The Bolo gets a powerful panorama E/O optics suite as well as laser and radar rangefinders for its main gun. The parasite turret gets binocular E/O sensor and an optical coincidence rangefinder. The tank commander also gets an independent E/O sensor suite, which even has a small optical rangefinder, with two small peepholes situated on either side of the sensor stack. To improve its survivability, it is also equipped with a hemispheric IR threat detector, allowing it to keep an eye on its surroundings. A GPS Blue-force-tracker is standard.
Last but not least, the vehicle gets a 6-point LADAR and two pairs of binocular Navigation cameras to allow the vehicle to drive itself.
Upgrades[]
Environment Gage[]
To effectively counter the effects of the environment at ultra-long distances, the Bolo can be equipped with a roof-mounted environment sensor to accurately monitor the wind, temperature, and precipitation (rain, snow or hail).
M117[]
The tiny amount of space behind the tank allows the XM520 to carry a single M117B Mastiff, along with the drone's own variable-height (to allow roll-on/roll-off) stowage compartment. It can be deployed (and recovered) and operated by the crew without leaving the vehicle. Boosts situation awareness—the M2 that it mounts isn't bad at all, either.
Best of all? The AI operates it. While firing on an enemy tank and fending off a clump of infantry ambushing the tank at the same time.
Armament[]
Rheinmetall L/40 140mm (1)[]
In the 1990s, rumor had it that next-generation Soviet armor would be armed with a 135mm or 152mm cannon. The Germans went so far as to design a completely new gun (turret included) for the Leopard 2; the US put a 140mm onto an M1 called “Thumper”, and even conducted trials for the gun. However, the requirement died when the USSR died, and so the gun was shelved. Now, with the Imperium having 152mm cannon-armed tanks, and the Asians mounting a massive 8' gun, the gun was revived.
Mated to the tank's E/O suite, dual rangefinders, and advanced firing computer (that can even learn from experience, hence called an AI), it can effectively track, target, and eliminate enemies up to 4,500 meters away. It is equipped with an autoloader that draws on a 35-shell stock of DM73/M830 APFSDS-T shells (an M829A4 with 1.5 times the mass, at the same velocity, resulting in 1250mm RHAe penetration and an extra 25% range) and DM21 PHE shells (able to shed infantry with airburst, or rip apart bunkers with delayed action), allowing it to effectively engage a wide variety of targets.
M240 (1)[]
As a way to keep enemy infantry away, and keep the AI occupied when the autoloader is replenishing the gun, an M240 7.62mm machine gun is fitted beside the Rheinmetall in a co-axial mount. It draws from a 1000-round magazine.
General Atomics MAWS A-20 (1)[]
The Magnetic Acceleration Weaponry Systems Artillery-20 is a military-grade railgun. Firing tungsten 20mm sabots, the gun uses electricity to accelerate them to a blistering 2,100 meters per second, an increase of 50%, to a maximum range of 4,000 meters. At point-blank range, the sabot can rip through twenty centimeters of solid steel—making it able to tear apart enemy light vehicles with ease. Effective RoF 10rpm. The weapon is mounted in its own parasite turret.
Microwave Cannon (1)[]
The newest development in crowd control, the Microwave Cannon is a small turret top-mounted directed energy weapon that has two modes: Low (which makes the target feel like burning up) and High (which makes the target literally burn up). The weapon can easily penetrate any non-metal material, making sandbags or brick walls a bad place to hide behind. Makes infantry think three times before engaging the Bolo. Maximum range 100m. Mounted co-axial with the light railgun.
Upgrades[]
Rheinmetall L/44 140mm ETC Smoothbore Cannon[]
To boost muzzle velocity via more efficient use of the propellant charges, the 140mm cannon can get an Electro-Thermal Chemical propellant ignition system. FLARE is a plasma-ignition system, allowing the cannon to use high-density rapid-expansion propellants. This boosts muzzle velocity by 1.3 times. Increases M830 RHAe penetration past 1500mm, and boosts range by 20% as well.
XM831 ALARM-140[]
The Advanced Long Attack Range Munition was developed to counter the ultra-heavily-armored T-120 and later, the T-150. The NAU developed one for the 140mm cannon as well. Longer than the original DM73, the ALARM-140 carries the same segmented fin-stabilized DU penetrator (equipped with a new low-drag ballistic cap), but incorporates a small slow-burning rocket motor on the end of the sabot, which ignites as soon as the sabot is discarded. The rocket allows the sabot to retain its muzzle velocity over two kilometers, increasing range by 25% and making a 4-kilometer hit as deadly as a previous 2-kilometer hit.
VIRCATOR[]
To counter the multitude of electronics on the battlefield, the Bolo can fire a VIRCATOR 140mm shell. VIRCATOR is a directed electromagnetic pulse firer, which can blow out the fuzes/short circuit all the wiring in the immediate vicinity of the detonation. Very handy for dealing with high-tech anti-tank weapons like ATGMs—especially their launchers.
Protection[]
The XM520 is protected by multiple AMAP modules, just like the Spartan, but thanks to not having the space of one human being and the massive diesel W-12 (and its fuel tanks), it has the space and weight to spare—which was used in up-armoring. The base AMAP modules protects the tank from 40mm APFSDS rounds, while additional AMAP-B plating on the front arc gives it more than 1500mm RHAe. DU Inserts flatten any APFSDS rods should they penetrate the outer layer. RPGs are countered by AMAP-P, cluster-munition explosively formed penetrators are defied by AMAP-R, and 200kg IEDs feel like running over a bump, thanks to AMAP-M. To reduce the brunt of penetrating projectiles, AMAP-L is applied to the inside of the turret, reactor compartment, and crew cocoon. The Bolo is also equipped with ElRA tiles on the sides and rear of its hull, and on its turret, vastly increasing its protection against enemy fire. Last but not least, it has an AMAP-ADS suite that blows up guided missiles.
In addition to external armor, the one-man crew (and AI core) of the XM520 are encased in their own AMAP&steel cocoon, which has about 1500mm RHAe. Coupled with internal food and water supplies, plus a backup graphene-boosted lithium-polymer battery, the operators (man and machine included) of a Bolo have survival rates of about 100%, because they can last for a week inside a knocked-out Bolo before getting rescued.
Upgrades[]
DTHEL[]
The Defensive Tactical High Energy Laser is the miniature version of the original THEL, mated to a search radar and a LADAR targeting suite. The relative low-powered deuterium fluoride chemical laser pumps out just enough energy to fry a shell or a rocket or a missile at one kilometer—under perfect conditions.
EMP Hardening[]
To provide the Bolo with even more resistance to EMP attacks, it can receive easy-to-replace fuzes as well as Faraday cages around critical components.
Mobility[]
The XM520 owes its plentiful power supply to a miniature 4th generation Liquid Thorium Fluoride Reactor. Not quite a “quarter-sun fission plant”, but when coupled to a thermoelectric turbine generator and a Stirling engine, the LTFR can provide the tank with a steady 2.1MW, which is either stored in the tank's massive lithium-polymer battery block, or used in the tank's four drive-sprocket high-output hub motors, which deliver an insane 500hp each.
It can move the 60-ton tank at 160 kilometers per hour on paved roads, and, thanks to its advanced hydropneumatic “kneeling” suspension (that be used to lower the vehicle from 60cm of ground clearance for cross-country maneuvering to 10cm for hull down) 80 kmph on rough terrain. Reactor heat is dumped downwards, and thanks to not having an engine, it has almost no acoustic signature. The tracks are reinforced to endure the increased punishment, and to increase durability against external force.
Upgrades[]
None.