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Nightrider_88 · 03-14-2023, 07:47 AM

Heh. So, there was a discussion deep in he Discord, and one of us came up with a set of ideas for a futuristic heavy tank. I liked that idea and since then I'm thinking how well it would translate into GURPS.

So, thing than were said:
Main armament: It's a massive 15cm/60cal high pressure composite barrel gun made from a carbon fiber tube impregnated in a titanium matrix with its bore nitrided about a third its way through, firing a 20kg semi-segmented, sleeved, telescoping, uranium alloy penetrator at 2400m/s using a powerful propellant based on CL-20 and ADN (plus additives, mostly to reduce combustion speed). The resulting rod can go through over 2mRHAe with approximately twice the spalling of a modern one. It uses combustible casings and a super-lightweight sabot made from fancy carbon-carbon composite, which makes the gun very efficient overall and an easy job for the autoloader. The gun can also fire missiles for indirect fire, including kinetic and chemical warheads, as well as other specialist shots as the gun can double as artillery if needed Its not wholly segmented, but the rod is internally shaped in a similar way, with a pattern of ductile and stiff alloy that reduces mushrooming. It's all uranium except for a very thin sleeve of TWIP steel around the penetrator to protect it from shearing. A cool thing is that the projectile does not suffer too hard from overpen as the wide and mushrooming sleeve spalls a lot in the first third or so of the penetration. Should carry 40 rounds, more is not impossible but neither likely, less would be used if needed. It can carry missiles split between two pieces too. All of the ammo spaces are isolated from the crew and each other, covered by panels, armored and fireproofed with a wet gel that may or may not be a horrible ozone depleter
There's two ammo spaces separated by a bulkhead with the loader in the middle, and also a buffer in the turret for rapid fire, tho it should only be filled when the firepower is needed, which us rarely as the tank is designed to one hit kill

Secondary armament: Its main secondary weapon is a heavy armored autocannon on top of the autoloader part of the turret. It has good elevation and depression and a very high fire rate, with enough power to shred IVF and incapacitate tanks; however it has relatively little ammo. It can target independently from the main turret and traverses fast... The idea is that it's able to swap barrels for a smaller one if the low ammo proves a weakness (e.g. urban combat), but so far I've had trouble designing such a loading mechanism... It also has canisters for loitering munitions A laser for drone defense that could be used as a weapon too An automatically aimed 20mm cannon which, depending on the version of the tank is mounted in various places, on top of the cannon, coaxial to it, to the gun or on the back of the tank, and it's a bit of another layer of point defense plus ****ing infantry. The 50cal is pretty boring but the 2cm has two rounds: a high velocity incendiary sabot and a big fat timed fuze shrapnel, with AHEAD-like design, but the casing is a continuous rod and the beads are long and made of a flammable uranium alloy.

Front hull armor: ERA followed by a complex composite armor mostly based on tiled NXRA, using PE/PE as rubber with a bit of explosive mixed in. The plates contain fancy **** like nanocrystalline titanium with various treatments, TWIP steel or superplastic CMC

Side armor: two layer ERA, one shaped charge the other flier plate based, angled in a sight V, triggered early by magnetic detectors, followed by a tightly packed composite of fancy ceramics and stupidly ductile steels, in thick plates separated by rubber and glassed titanium foam spacers. The side armor is less weight efficient but incredibly space efficient, and it saves weight from ERA.

Powerplant: Also there's a variant using aluminum fuel, which is more expensive, slightly heavier and harder to refuel but doubles range and adds a bit of protection to the engine. It also could run underwater (wirming out the how) and has no exhaust.
Its fed as a dust, dissolved in gallium and fed through a fuel cell, with the oxide dropped to the ground as incredibly fine crystals precipitating out of the solvent
Another cool thing of alu is that it needs very little air (5ish times more vs 15ish for diesel) so that's a much smaller weakness at the intake
In theory it could run underwater too, this is very useful for crossing large water bodies without a snorkel, but it's need to be figure out how to make the engine be able to switch modes without pulling it out

60 tons. Unmanned turret. RHA equivalent of the hull armor should be about meter.

03-14-2023, 07:47 AM	#1
Nightrider_88 Join Date: Nov 2019	TL9 Heavy Tank Heh. So, there was a discussion deep in he Discord, and one of us came up with a set of ideas for a futuristic heavy tank. I liked that idea and since then I'm thinking how well it would translate into GURPS. So, thing than were said: Main armament: It's a massive 15cm/60cal high pressure composite barrel gun made from a carbon fiber tube impregnated in a titanium matrix with its bore nitrided about a third its way through, firing a 20kg semi-segmented, sleeved, telescoping, uranium alloy penetrator at 2400m/s using a powerful propellant based on CL-20 and ADN (plus additives, mostly to reduce combustion speed). The resulting rod can go through over 2mRHAe with approximately twice the spalling of a modern one. It uses combustible casings and a super-lightweight sabot made from fancy carbon-carbon composite, which makes the gun very efficient overall and an easy job for the autoloader. The gun can also fire missiles for indirect fire, including kinetic and chemical warheads, as well as other specialist shots as the gun can double as artillery if needed Its not wholly segmented, but the rod is internally shaped in a similar way, with a pattern of ductile and stiff alloy that reduces mushrooming. It's all uranium except for a very thin sleeve of TWIP steel around the penetrator to protect it from shearing. A cool thing is that the projectile does not suffer too hard from overpen as the wide and mushrooming sleeve spalls a lot in the first third or so of the penetration. Should carry 40 rounds, more is not impossible but neither likely, less would be used if needed. It can carry missiles split between two pieces too. All of the ammo spaces are isolated from the crew and each other, covered by panels, armored and fireproofed with a wet gel that may or may not be a horrible ozone depleter There's two ammo spaces separated by a bulkhead with the loader in the middle, and also a buffer in the turret for rapid fire, tho it should only be filled when the firepower is needed, which us rarely as the tank is designed to one hit kill Secondary armament: Its main secondary weapon is a heavy armored autocannon on top of the autoloader part of the turret. It has good elevation and depression and a very high fire rate, with enough power to shred IVF and incapacitate tanks; however it has relatively little ammo. It can target independently from the main turret and traverses fast... The idea is that it's able to swap barrels for a smaller one if the low ammo proves a weakness (e.g. urban combat), but so far I've had trouble designing such a loading mechanism... It also has canisters for loitering munitions A laser for drone defense that could be used as a weapon too An automatically aimed 20mm cannon which, depending on the version of the tank is mounted in various places, on top of the cannon, coaxial to it, to the gun or on the back of the tank, and it's a bit of another layer of point defense plus **ing infantry. The 50cal is pretty boring but the 2cm has two rounds: a high velocity incendiary sabot and a big fat timed fuze shrapnel, with AHEAD-like design, but the casing is a continuous rod and the beads are long and made of a flammable uranium alloy. Front hull armor: ERA followed by a complex composite armor mostly based on tiled NXRA, using PE/PE as rubber with a bit of explosive mixed in. The plates contain fancy ** like nanocrystalline titanium with various treatments, TWIP steel or superplastic CMC Side armor: two layer ERA, one shaped charge the other flier plate based, angled in a sight V, triggered early by magnetic detectors, followed by a tightly packed composite of fancy ceramics and stupidly ductile steels, in thick plates separated by rubber and glassed titanium foam spacers. The side armor is less weight efficient but incredibly space efficient, and it saves weight from ERA. Powerplant: Also there's a variant using aluminum fuel, which is more expensive, slightly heavier and harder to refuel but doubles range and adds a bit of protection to the engine. It also could run underwater (wirming out the how) and has no exhaust. Its fed as a dust, dissolved in gallium and fed through a fuel cell, with the oxide dropped to the ground as incredibly fine crystals precipitating out of the solvent Another cool thing of alu is that it needs very little air (5ish times more vs 15ish for diesel) so that's a much smaller weakness at the intake In theory it could run underwater too, this is very useful for crossing large water bodies without a snorkel, but it's need to be figure out how to make the engine be able to switch modes without pulling it out 60 tons. Unmanned turret. RHA equivalent of the hull armor should be about meter.