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Old 03-18-2012, 03:50 AM   #21
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Default Re: [SS] Reigning in Projectile Damage

Not that it would fix much and I'm a bit groggy with lack of sleep so it might have already been mentioned , but in impacts beyond 2 kilometers per second even depleted uranium long rod penetrators fails to maintain their structure and effectivly disintegrate on contact with the target . Rather than punching a hole in the Armour , they blast a shallow crater .

This means that beyond 1.25 miles per second any armour divisor will cease to work .
For G.U.R.P.S. Space Ships , it would be safe {reality wise} to have no armour divisor for most missiles {including APEX warheads} beyond 1 mile per second and pure A.P. type projectiles beyond 2 miles per second .





If it really still bugs you , it doesn't take much higher velocities to turn any projectile into a plasma .
You could scrap existing plasma weapons and call the S.S. guns plasma cannon and missiles fusion missiles {just add a bonus for point defense so missiles don't allways get through} .
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Old 03-18-2012, 04:16 AM   #22
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Default Re: [SS] Reigning in Projectile Damage

For space operah balance, I think the simplest solution is:
  1. Remove the Kinetic Kill element from the equation by making all missiles pseudovelocity (or inertialess). Say that rocket science never got past TL6-TL7, because the first pseudovelocity drives were invented around early TL7. Damage comes from warheads. See below.
  2. Take an SM+10 ship, figure its HP, its likely minimum and maximum armour ratings, and scale all SM+10 weapon system damage to the levels you like.
  3. Create a table where weapon damage scales with SM the same way HP does.
  4. Cremate, with honours, any pretence to realistic numbers, then forget it.
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Old 03-18-2012, 04:38 AM   #23
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Default Re: [SS] Reigning in Projectile Damage

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Originally Posted by vicky_molokh View Post
For space operah balance, I think the simplest solution is:
  1. Remove the Kinetic Kill element from the equation by making all missiles pseudovelocity (or inertialess). Say that rocket science never got past TL6-TL7, because the first pseudovelocity drives were invented around early TL7. Damage comes from warheads. See below.
  2. Take an SM+10 ship, figure its HP, its likely minimum and maximum armour ratings, and scale all SM+10 weapon system damage to the levels you like.
  3. Create a table where weapon damage scales with SM the same way HP does.
  4. Cremate, with honours, any pretence to realistic numbers, then forget it.
Hehe, and that's exactly what my original proposal was (though normalizing around SM +9 instead of SM +10). HP and Beam weapons stay the same, with guns and missiles inflicting x1.5 and x3 the damage of a same-sized beam, respectively. I don't know if I'll try that in a game anytime soon, though.

Right now I'm looking at the implications of some of the options presented in Pyramid 3/34 and elsewhere. I'm not sure I like changing the whole HP and Beam weapon progressions (using the Square Root options) since I had no complaint with them... but it does produce some interesting results. It makes small missiles not as overpowering, but large missiles become utterly useless. Another side effect is that DR rapidly becomes ineffective unless heavily layered.

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Originally Posted by Mr Frost View Post
Not that it would fix much and I'm a bit groggy with lack of sleep so it might have already been mentioned , but in impacts beyond 2 kilometers per second even depleted uranium long rod penetrators fails to maintain their structure and effectivly disintegrate on contact with the target . Rather than punching a hole in the Armour , they blast a shallow crater .

This means that beyond 1.25 miles per second any armour divisor will cease to work .
For G.U.R.P.S. Space Ships , it would be safe {reality wise} to have no armour divisor for most missiles {including APEX warheads} beyond 1 mile per second and pure A.P. type projectiles beyond 2 miles per second.
In that case, would there be any disincentive to always use Proximity Burst, since you wouldn't have an Armor Divisor anyways? I do feel like, if Proximity is supposed to represent spraying the target with fragments, the mechanics should reflect that (ie, higher RoF, lower damage per hit) rather than the simplified method it currently uses. Damage could potentially exceed that of an individual warhead, which could represent a wider spread of damage affecting more vital systems.

Last edited by vierasmarius; 03-18-2012 at 04:44 AM.
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Old 03-18-2012, 06:57 AM   #24
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Default Re: [SS] Reigning in Projectile Damage

Okay, one more question. I've recalculated the Nuke damage using the cube root method from Pyramid 3/34. However, the explosion rules in Basic assume damage based on the square root of mass. As a result, the blast radius of large explosions is greatly diminished if using this alternate progression, giving results that are unrealistically small. Should I be using some different scale to determine damage at a given distance? If so, what would be the damage divisor for a nuke detonating as a Proximity Burst (approx 50 yards from target)?
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Old 03-18-2012, 07:40 AM   #25
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This interests me. My intent is to change the feel of military confrontations. How do the above options make the published military vessels' stats useless?
Useless to me:) I like the Starfire, battleships-in-space feel. They're okay-ish at SM8-10 but my larger designs are tanks-in-space, eg a 150,000 ton Hera class kampf zielen, SM+12, dHP 3,000, dDR 1,200, mounts a 30gj UV pulse laser 5dx100 Cr Ex, 70,000/210,000* miles and has IT:DR2. The laser won't even damage a section without an above average roll but an a-mat missile will vaporise the entire ship, if it gets anywhere near it.
It's 45% armour by mass, 75% by cost. I've probably missed it but I didn't see anything similar in the published material.
*I extrapolated the range stats; did something similar for missiles and it turns out it matches sensor ranges for their SM quite neatly. It means "big gun" range can exceed a missile's lock-on range so smaller vessels can be dead before they get to launch.
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Old 03-18-2012, 07:50 AM   #26
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Useless to me:) I like the Starfire, battleships-in-space feel. They're okay-ish at SM8-10 but my larger designs are tanks-in-space, eg a 150,000 ton Hera class kampf zielen, SM+12, dHP 3,000, dDR 1,200, mounts a 30gj UV pulse laser 5dx100 Cr Ex, 70,000/210,000* miles and has IT:DR2. The laser won't even damage a section without an above average roll but an a-mat missile will vaporise the entire ship, if it gets anywhere near it.
It's 45% armour by mass, 75% by cost. I've probably missed it but I didn't see anything similar in the published material.
*I extrapolated the range stats; did something similar for missiles and it turns out it matches sensor ranges for their SM quite neatly. It means "big gun" range can exceed a missile's lock-on range so smaller vessels can be dead before they get to launch.
Ah, I see. Well, I don't have a specific setting in mind yet (ie, no specific ship designs). I'm just trying to come up with an array of tools to tweak the setting for the desired feel. It sounds like you've put a lot of thought into your setting and ships; I'd be curious to see some of their schematics.
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Old 03-18-2012, 08:27 AM   #27
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what would be the damage divisor for a nuke detonating as a Proximity Burst (approx 50 yards from target)?
(5) probably.Nukes in space emit nothing but X-rays, gamma rays, fast charged particles and neutrons in what is effectively a single short but highly intense pulse.

This makes the explosions look more like X-ray lasers or particle beams than any other standard weapon in Gurps. With greater range base damage goes down, not the divisor.
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Old 03-18-2012, 08:56 AM   #28
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(5) probably.Nukes in space emit nothing but X-rays, gamma rays, fast charged particles and neutrons in what is effectively a single short but highly intense pulse.

This makes the explosions look more like X-ray lasers or particle beams than any other standard weapon in Gurps. With greater range base damage goes down, not the divisor.
Oops, I think I misstated my question. Under the RAW explosion rules (with damage based on square root of TNT equivalent) the thermal burst from a nuke is divided by 2*range, giving 1/100 at 50 yards (which is apparently the distance of a Proximity Detonation in Spaceships). If using the alternate cube root damage from Pyramid 3/34, the damage drop-off should logically be shallower, otherwise the lethal radius of a nuke wouldn't match its real-life statistics. So, when using cube root of payload equivalent for nuke damage, how much should damage be reduced at 50 yards?
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Old 03-18-2012, 09:17 AM   #29
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. So, when using cube root of payload equivalent for nuke damage, how much should damage be reduced at 50 yards?
<shrug> Can't help you. I haven't read the article in question. I don't voluntarily do cube roots either.

In reality a nuclear explosion in vacuum is a very simple surface of an expanding (and hollow) sphere. The energy of a nuclear explosion at 50 yards is a sphere 2500x the aurface area of a sphere at 1 yard.
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Old 03-18-2012, 09:33 AM   #30
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Default Re: [SS] Reigning in Projectile Damage

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<shrug> Can't help you. I haven't read the article in question. I don't voluntarily do cube roots either.

In reality a nuclear explosion in vacuum is a very simple surface of an expanding (and hollow) sphere. The energy of a nuclear explosion at 50 yards is a sphere 2500x the aurface area of a sphere at 1 yard.
Ah, right. And because the energy of the explosion is proportional to the mass, that's equivalent to an explosion of 1/2500 the mass. For a 25kt nuke (dDam 6dx80) at 50 yards, the thermal burst is equivalent to 10 tons of TNT, roughly 6dx6 dDam (this is lower than the normal damage of 10 tons TNT because it's only counting the thermal energy, not the concussive blast). This is 7.5% of the initial damage, or a divisor of 13.3, which is conveniently 50^(2/3). My mind is fuzzy right now (d*** insomnia!) so I can't wrap my head around exactly why that correlation occurs, but it's about what I expected.

This progression (damage ÷ range^[2/3]) would only hold true for simple explosions like the thermal burst in a vacuum. I suspect it becomes far more complicated with shockwaves in a thick medium. I'm definitely not gonna tackle it right now... I've got the answer that I was really looking for, anyways.

Thanks everyone for your assistance and criticism! It really helped me put my thoughts in order, and led me to explore several new possibilities.

Last edited by vierasmarius; 03-18-2012 at 09:47 AM.
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