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Old 09-23-2018, 06:28 AM   #11
AlexanderHowl
 
Join Date: Feb 2016
Default Re: [Spaceships] Proposal for building missiles as spaceships

I generally think that the missile rules are adequate as they are. If you want to make a series of AKVs though, feel free, as they can also carry missiles. For example, a SM+4 AKV can reasonably carry 10 major missile batteries, each equipped with 5 16cm missiles, which translates to 50 16cm missiles. Now, it is probably not doing much traveling, but a SM+10 AKV carrier could carry 300 of them without difficulty, meaning that it could potentially launch 3,000 16cm missiles every turn when all of its AKVs are deployed. Good luck dealing with that much hate.
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Old 09-23-2018, 11:05 PM   #12
Varyon
 
Join Date: Jun 2013
Default Re: [Spaceships] Proposal for building missiles as spaceships

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Originally Posted by Michael Thayne View Post
You could fix it with a warhead system, as mentioned by Agememnos, though that would further degrade performance.
Depends on what systems the missile already has. If it has any volatile systems, a pretty simple mechanism should be enough to blow up said system. HEDM fuel works for TL9 missiles, and above TL 9 a small bit of antimatter (not enough to count as an antimatter warhead, but enough to break the missile apart) might be an option. At TL8 and lower, I think you're pretty much stuck wasting some cargo space on explosives, although how much is needed would be something to consider (a missile that's designed to fragment might require only a tiny amount of high explosive - compared to the missile's total mass - to break apart).
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Old 09-24-2018, 11:22 AM   #13
Fred Brackin
 
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Default Re: [Spaceships] Proposal for building missiles as spaceships

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D above TL 9 a small bit of antimatter (not enough to count as an antimatter warhead, but enough to break the missile apart) might be an option.
Antimatter would be a poor choice for self-destruct. The smallest antimatter warhead in UT (0.1 micrograms) does 6dx4 and as an internal explosion that's in the rigth area to shred a missile. However, it also does an average of 210,000 rads and causign organic beings like humans to die slow and painful deaths from radiation poisoning has to be viewed as its' primary effect.

Also, at TL10 such an antimatter charge requires a 100mm warhead which probably weighs about 5 lbs. 6Dx4 is the effect of 4 lbs of TNT so antimatter is literally an inefficient way to destroy inorganic devices. the gamma rays antimatter produces just shoot right through.

If you wonder, At TL7 and 8 space launching missiles as used at KSC do have self-destructs for safety but they consist of det cord placed around the inside of the hull and probbaly the more solid other components. This would be one of those situations where contact explosives do get maximum damage so weight does not have to be large in terms of a sizable vehicle.
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Old 09-24-2018, 12:01 PM   #14
AlexanderHowl
 
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Default Re: [Spaceships] Proposal for building missiles as spaceships

Antimatter explosions also do not react the way that GURPS portrays them. Only the positron-electron reactions produce pure gamma ray emissions, larger particles (protons and neutrons) and atoms produce much more complex reactions. The pion, kaon, and muon mix that comes from combining protons and antiprotons would have...odd explosions.
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Old 09-24-2018, 12:16 PM   #15
Fred Brackin
 
Join Date: Aug 2007
Default Re: [Spaceships] Proposal for building missiles as spaceships

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Antimatter explosions also do not react the way that GURPS portrays them. Only the positron-electron reactions produce pure gamma ray emissions, larger particles (protons and neutrons) and atoms produce much more complex reactions. The pion, kaon, and muon mix that comes from combining protons and antiprotons would have...odd explosions.
All those mesons you mention have very short half-lives. They decay into more gamma rays before much else can happen. They barely live long enough to be shot out of hard science antimatter drives before they decay (into gamma rasy of course). That's why I have usually stopped noting other products of matter-antimatter annihilation.

Though as long as we're beign persnicketly about this there is the case where anti-protons are energeticaly propeled into large nuclei like uranium. That blows the whole nucleus apart and gets you energetic nuclear fragments that end up as heat and many more neutrons than regular fission. This is what the so-called "antimatter warheads" in Spaceships are actually doing. They're using antimatter to make better fission bombs.

Antimatter technology that isn't superscience is limited to just a few specialized uses..
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Old 09-24-2018, 12:51 PM   #16
Michael Thayne
 
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Default Re: [Spaceships] Proposal for building missiles as spaceships

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Originally Posted by AlexanderHowl View Post
I generally think that the missile rules are adequate as they are. If you want to make a series of AKVs though, feel free, as they can also carry missiles. For example, a SM+4 AKV can reasonably carry 10 major missile batteries, each equipped with 5 16cm missiles, which translates to 50 16cm missiles. Now, it is probably not doing much traveling, but a SM+10 AKV carrier could carry 300 of them without difficulty, meaning that it could potentially launch 3,000 16cm missiles every turn when all of its AKVs are deployed. Good luck dealing with that much hate.
Existing missile rules have a couple problems:

1) Their performance as given in Spaceships 3 makes little sense—you can get them with a rocket that's engines and fuel and nothing else, but that leaves you with no room for e.g. a nuclear warhead.
2) More importantly, a 4-ton missile is no harder to destroy with point defense than a ~130-lb. missile. This makes the heavier missiles rather useless. This wildly distorts things if you seriously try to optimize warship designs.
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Old 09-24-2018, 01:29 PM   #17
Fred Brackin
 
Join Date: Aug 2007
Default Re: [Spaceships] Proposal for building missiles as spaceships

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Originally Posted by Michael Thayne View Post
Existing missile rules have a couple problems:

1
2) More importantly, a 4-ton missile is no harder to destroy with point defense than a ~130-lb. missile. This makes the heavier missiles rather useless. This wildly distorts things if you seriously try to optimize warship designs.
The 4 ton missile is probably easier to destroy because of its' greater SM.

A careful study of UT makes you wonder if really gigantophiliac tech serves a lot of purpose. The 100 mm Tactical Missile is extremely potent in many uses with even simple warheads and it can carry a 1 kiloton nuclear warhead. Actually there is a line in Spaceships 1 for 100mm missiles carrying 100 kt warheads at the right TL.
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Old 09-24-2018, 01:53 PM   #18
Michael Thayne
 
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Default Re: [Spaceships] Proposal for building missiles as spaceships

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Originally Posted by Fred Brackin View Post
The 4 ton missile is probably easier to destroy because of its' greater SM.

A careful study of UT makes you wonder if really gigantophiliac tech serves a lot of purpose. The 100 mm Tactical Missile is extremely potent in many uses with even simple warheads and it can carry a 1 kiloton nuclear warhead. Actually there is a line in Spaceships 1 for 100mm missiles carrying 100 kt warheads at the right TL.
These are good points, though with armored missiles things like the one-ton fusion pulse missile I sketched above can fill a niche of "a 10-ton drone is too heavy, but you want to get past small point defense guns." Potentially gets you out of the equilibrium where every capital ship has a one-SM smaller tertiary battery, which is honestly quite odd.
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Old 09-24-2018, 02:56 PM   #19
AlexanderHowl
 
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Default Re: [Spaceships] Proposal for building missiles as spaceships

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Originally Posted by Fred Brackin View Post
All those mesons you mention have very short half-lives. They decay into more gamma rays before much else can happen. They barely live long enough to be shot out of hard science antimatter drives before they decay (into gamma rasy of course). That's why I have usually stopped noting other products of matter-antimatter annihilation.

Though as long as we're beign persnicketly about this there is the case where anti-protons are energeticaly propeled into large nuclei like uranium. That blows the whole nucleus apart and gets you energetic nuclear fragments that end up as heat and many more neutrons than regular fission. This is what the so-called "antimatter warheads" in Spaceships are actually doing. They're using antimatter to make better fission bombs.

Antimatter technology that isn't superscience is limited to just a few specialized uses..
Is it? I would think that would merely create a fission reaction, with the antimatter just being a more efficient trigger than conventional explosives.

Decay times are tricky due to the energy levels. Many of the particles are moving at near c, so they take a longer objective time to decay that they would if they were standing still. For example, a charged pion lasts 26 ns but, when traveling at near c, it might experience a 20:1 time dialation, meaning that the objective time for decay is 520 ns. At near c, 520 ns means the pion travels 156 m before decaying into a muon/antimuon. Muons/antimuons in turn, last 2 microseconds, turning into 40 microseconds at near c, meaning that they travel 12 km before decaying into electrons/positrons.
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Old 09-24-2018, 07:36 PM   #20
Varyon
 
Join Date: Jun 2013
Default Re: [Spaceships] Proposal for building missiles as spaceships

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Also, at TL10 such an antimatter charge requires a 100mm warhead which probably weighs about 5 lbs. 6Dx4 is the effect of 4 lbs of TNT so antimatter is literally an inefficient way to destroy inorganic devices. the gamma rays antimatter produces just shoot right through.
At worst, an antimatter warhead would be comparable to HEC, and the lack of mention of a poor armor divisor implies SAPHE/SAPHEC is more likely. Going off of the guidelines in HT, that implies somewhere between 10% and maybe 30% of the warhead is explosive, meaning an effective REF for the antimatter+containment portion of the warhead of between 2.5 (for 30%) and 8. That is indeed not as good as I was expecting (the metallic hydrogen based explosives of TL10 have REF 6), so you probably wouldn't be seeing an antimatter-based system prior to TL11. Well, unless you can have APHEX antimatter warheads at TL10, anyway (which would probably put effective REF at an impressive 15 or higher, which outdoes even TL11 plasma explosives).
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