01-06-2011, 01:04 PM | #1 |
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[Spaceships] Heat Signature, Cloaking Device, and Stealth Hull
Greetings, all!
In preparation for my space campaign, I'm looking over how detection works. There are some things that look either unresolved, or at least not 'doubtless' even if RAW. Specifically: What is the Heat Signature of a Hot Reactionless drive or Boost Drive? RAW mentions 'as a reaction drive' - how much is that? Stealth Hull requires a signature of +4 or lower to affect the detection roll. At TL10 it gives -2×(TL-6)==-8. Auxiliary power is a Signature of +3 anyway, unless one is willing to turn off life support (and active sensors, if it matters). Cloaking Device (SS1:13) says it makes a ship 'invisible' to sensors, but that it can be seen if it fires weapons or uses a reaction drive. Detection mentions -10 (-4 if already detected (?)), and nothing about weapons affecting it. Should that be interpreted as Basic Set Invisibility until weapons/drives use? Also, the device is energy-intensive, which likely requires having a Fusion or similar reactor active. This puts it at odds with the Stealth Hull, unless it reduces the signature. Nothing gives me reason to believe that it does except my personal idea of what seems sensible. So, if my idea is wrong and RAW is right, a Cloaking Device gives de-facto -20 to detection (negates Plain Sight, and gives -10), plus 5 or more for the reactor. Stealth Hull, by comparison, provides de-facto -8, plus 3 unless one can ditch life support, but doesn't require a system slot, doesn't require power, cannot be disabled . . . but doesn't provide a penalty to being hit either. Also, should Cloaking Device negate the Silhouetted Against Deep Space modifier (+24)? Again, no indication in RAW that it should, but my hunchy feeling says this isn't necessarily so. If it does, this makes the cloak much, much more desirable. Answers? Opinions? Suggestions? Comments? Thanks in advance! |
01-06-2011, 01:58 PM | #2 |
Join Date: Feb 2006
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Re: [Spaceships] Heat Signature, Cloaking Device, and Stealth Hull
Heat signature: Hot says it has the signature of a conventional drive. The nearest match for thrust is something like an A-mat Plasma Torch, +10 signature. But it does seem either errata or that you're meant to pick the rating yourself to suit your setting.
Cloaking device: Silhouetted is cumulative with Plain Sight but Cloaking cancels Plain Sight: nothing to see (invisible), so no silhouette sounds logical. So does the "those stars just rippled" line of thought. But I'd go with the Star Trek version.
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01-06-2011, 02:11 PM | #3 |
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Join Date: Sep 2005
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Re: [Spaceships] Heat Signature, Cloaking Device, and Stealth Hull
I wouldn't allow cloaking devices to eliminate the plain sight bonus.
EDIT: Nevermind, I was thinking of the "silhouetted against deep space" bonus. I wouldn't allow it to negate that. AM Plasma Torch or Total Conversion Torch have +10 or +11 to detect respectively and the same accel as the hot reactionless, I'd pick whichever number you like the best. For getting both stealth hull and cloaking device on the same ship, you could use a system of solar panels. But basically a realistic stealth hull is only handy if you're not radiating like a small star. Last edited by Crakkerjakk; 01-06-2011 at 02:25 PM. |
08-25-2015, 07:47 AM | #4 |
Join Date: Dec 2006
Location: Eindhoven, the Netherlands
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Re: [Spaceships] Heat Signature, Cloaking Device, and Stealth Hull
This seems the best place to ask (hence my sinister necromancy): Does a Stealth Hull and Cloaking actually stealth? Can you be more invisible than invisible? Super-extra invisible?
I originally thought they could be, but now I wonder. Cloaking seems to imply the maximum possible penalty (you're invisible), but not only can TL 12 stealth hulls exceed that (-12), but it seems they can stack... for a -22 (plus eliminating the plain-sight bonus of +10, giving them effectively a -32 compared to the average ship). Which is fine... perhaps that's the intent, but I just thought I would clarify. It seems like your spooky "submarine" ships need a stealth hull and some kind of low IR signature system, but while you can run a cloak on a warship, it's not really going to let you get the complete drop on him, especially as you get closer.
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08-25-2015, 08:13 AM | #5 |
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Join Date: Mar 2006
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Re: [Spaceships] Heat Signature, Cloaking Device, and Stealth Hull
At least for normal character-driven Stealth, Kromm said that the In Plain Sight bonus should not apply to a target that is trying to be stealthy in the first place. Not sure whether it's meant to work the same way with spaceships.
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08-25-2015, 10:19 AM | #6 |
Join Date: Aug 2008
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Re: [Spaceships] Heat Signature, Cloaking Device, and Stealth Hull
It's probably worth considering that there ain't no stealth in space. I think the best way to represent that is to always apply the In Plain Sight bonus, no matter what the ship is trying to do.
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08-25-2015, 10:26 AM | #7 |
Join Date: Feb 2005
Location: Berkeley, CA
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Re: [Spaceships] Heat Signature, Cloaking Device, and Stealth Hull
You can't really try to be stealthy in situations where there's absolutely no cover, so unless the ship is somewhere that cover exists (rings of Saturn, cinematic asteroid belt, etc), the in plain sight bonus would always apply. Though I'm not sure the bonuses are quite correct at the moment, I think spaceships may make detection range a bit too high (based on human visual sensitivity, sunlit target in space is about +25 total).
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08-25-2015, 10:34 AM | #8 | |
Join Date: Aug 2008
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Re: [Spaceships] Heat Signature, Cloaking Device, and Stealth Hull
Quote:
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08-25-2015, 11:23 AM | #9 | |
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Re: [Spaceships] Heat Signature, Cloaking Device, and Stealth Hull
Quote:
Stealth hulls, though, certainly aren't good enough.
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08-25-2015, 11:46 AM | #10 | |
Join Date: Aug 2008
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Re: [Spaceships] Heat Signature, Cloaking Device, and Stealth Hull
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cloaking device, detection, heat signature, spaceships, stealth hull |
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