Steve Jackson Games - Site Navigation
Home General Info Follow Us Search Illuminator Store Forums What's New Other Games Ogre GURPS Munchkin Our Games: Home

Go Back   Steve Jackson Games Forums > Roleplaying > GURPS

Reply
 
Thread Tools Display Modes
Old 08-25-2015, 11:46 AM   #11
Anthony
 
Join Date: Feb 2005
Location: Berkeley, CA
Default Re: [Spaceships] Heat Signature, Cloaking Device, and Stealth Hull

Quote:
Originally Posted by Humabout View Post
Consider that main engines of the Space Shuttle were visible from Uranus with current technology, though.
Probably not if it's on the ground, actually, but the separate issue is that the drive signature modifiers are a bit off (the SSME should have a total signature of around +24)
__________________
My GURPS site and Blog.
Anthony is offline   Reply With Quote
Old 08-25-2015, 01:16 PM   #12
weby
 
weby's Avatar
 
Join Date: Oct 2008
Default Re: [Spaceships] Heat Signature, Cloaking Device, and Stealth Hull

I get best overall results by ignoring "in plain sight" as modifier and giving a flat +10 to vision and sensor based detections where you take the time to do them. It is not perfect but it does have the effect of not having that sudden x50 jump in efficiency.

As for the stealth hull/cloaking and such: I specifically ignore the signature limits and allow the bonuses in all cases. That is not meant as realistic but as gameable.

Cloaking device: In my games it just gives a flat -10 for all sensor and vision rolls and is cumulative with stealth hull, you are still otherwise normally visible. It is generally available at TL 11^, but will have problems with too varied backgrounds, so gets full effect only when the silhouette against space.
In the upcoming big scifi campaign it will be only useful against the silhouette modifier and will raise in price as the size of the ship increases to mainly make it a feature of small vessels like scout ships and fighters.
__________________
--
GURPS spaceship unofficial errata and thoughts: https://gsuc.roto.nu/
weby is offline   Reply With Quote
Old 08-25-2015, 03:21 PM   #13
warellis
 
Join Date: Jan 2014
Default Re: [Spaceships] Heat Signature, Cloaking Device, and Stealth Hull

If one has reactionless engines, a refrigerated hull, & some form of heat sinks, how much easier is it to have some type of "stealth" in space?
warellis is offline   Reply With Quote
Old 08-25-2015, 03:29 PM   #14
Ulzgoroth
 
Join Date: Jul 2008
Default Re: [Spaceships] Heat Signature, Cloaking Device, and Stealth Hull

Quote:
Originally Posted by warellis View Post
If one has reactionless engines, a refrigerated hull, & some form of heat sinks, how much easier is it to have some type of "stealth" in space?
Do we have rules for that? I can't think of any...

The major problem with stealth, coming from the GURPS side, is that even with cool reactionless you need to get power from somewhere. And just about all power sources will blow your heat signature past the stealth threshold on their own.

EDIT: If you've got the switch where reactionless drives don't require power points to run, you're golden.
__________________
I don't know any 3e, so there is no chance that I am talking about 3e rules by accident.
Ulzgoroth is offline   Reply With Quote
Old 08-25-2015, 03:42 PM   #15
warellis
 
Join Date: Jan 2014
Default Re: [Spaceships] Heat Signature, Cloaking Device, and Stealth Hull

Quote:
Originally Posted by Ulzgoroth View Post
Do we have rules for that? I can't think of any...

The major problem with stealth, coming from the GURPS side, is that even with cool reactionless you need to get power from somewhere. And just about all power sources will blow your heat signature past the stealth threshold on their own.

EDIT: If you've got the switch where reactionless drives don't require power points to run, you're golden.
Hm can't they magically cram even the heat from a reactionless engine into some heat sink somewhere for a few hours or days or whatever?
warellis is offline   Reply With Quote
Old 08-25-2015, 03:44 PM   #16
Ulzgoroth
 
Join Date: Jul 2008
Default Re: [Spaceships] Heat Signature, Cloaking Device, and Stealth Hull

Quote:
Originally Posted by warellis View Post
Hm can't they magically cram even the heat from a reactionless engine into some heat sink somewhere for a few hours or days or whatever?
It's not the heat of the reactionless engine. It's the heat of the power plant that allows you to run the reactionless engine.
__________________
I don't know any 3e, so there is no chance that I am talking about 3e rules by accident.
Ulzgoroth is offline   Reply With Quote
Old 08-25-2015, 04:14 PM   #17
Anthony
 
Join Date: Feb 2005
Location: Berkeley, CA
Default Re: [Spaceships] Heat Signature, Cloaking Device, and Stealth Hull

Quote:
Originally Posted by warellis View Post
If one has reactionless engines, a refrigerated hull, & some form of heat sinks, how much easier is it to have some type of "stealth" in space?
Assuming your heat sinks are magical, you can suppress your IR output by quite a lot. The problem is that any realistic heat sink will fail in a very short time scale if used to keep your hull cool.
__________________
My GURPS site and Blog.
Anthony is offline   Reply With Quote
Old 08-25-2015, 04:48 PM   #18
ericbsmith
 
ericbsmith's Avatar
 
Join Date: Aug 2004
Location: Binghamton, NY, USA. Near the river Styx in the 5th Circle.
Default Re: [Spaceships] Heat Signature, Cloaking Device, and Stealth Hull

Quote:
Originally Posted by Anthony View Post
Assuming your heat sinks are magical, you can suppress your IR output by quite a lot. The problem is that any realistic heat sink will fail in a very short time scale if used to keep your hull cool.
I think the best idea along those lines was called a Hypersink in one of the Vehicles Companions - it essentially allowed you to dump your waste heat into hyperspace and thus keep your IR signature low when cruising around in normal space.
__________________
Eric B. Smith GURPS Data File Coordinator
GURPSLand
I shall pull the pin from this healing grenade and...
Kaboom-baya.
ericbsmith is offline   Reply With Quote
Old 08-25-2015, 05:53 PM   #19
safisher
Gunnery Sergeant,
 Imperial Marines
Coauthor,
 GURPS High-Tech
 
safisher's Avatar
 
Join Date: Oct 2004
Default Re: [Spaceships] Heat Signature, Cloaking Device, and Stealth Hull

A couple of thoughts here. First, in the "realistic" approach, we have just begun to tip our toes into metamaterials. The advances made in this field are taking us into GURPS TL^ territory. Everyone now screaming that "there is no stealth in space" assumes that everything works in the far future as we now understand it. Fine. But that's probably not very realistic.

Metamaterials, for instance, are proving that cloaking, fixed antennas which work like steerable ones, and a host of other applications will provide opportunities for things to work very different today than in the far future. Thus, there's very little "realistic" about trying to dispense with stealth or cloaking in space. This is like pointing to classic sci-fi with steel helmets and laser guns and saying that's the only realistic path forward.

And while others are going to jump on this and rail about my poor understanding of science, remember that warp drives are now no longer strictly a superscience consideration, and recent tests in fusion power and may make reactionless powered spacecraft possible in the near term. These are things real scientists are researching right now. However it all works, it's not unrealistic to propose that the idea of cloaking may be used in space. It may very optimistic, and it probably will look very strange to us, as the geometries involved may be very unusual compared to stock sci-fi swooshing spaceships.

http://www.nytimes.com/2015/03/24/sc...ials.html?_r=0

https://scholar.google.com/scholar?q...IVijySCh3lsAoD

https://scholar.google.com/scholar?q...0%2C4&as_vis=1

Second, if you want a superscience TL^ cloak, make it so. Wipe out all range, background, and other factors. Simply apply the -10 solely to the operator's skill. The end. A highly skilled operator might detect your cloaked ship, but otherwise, you are cloaked. End of story. You don't need any more justification than that.
__________________
Buy my stuff on E23.
My GURPS blog, Dark Journeys, is here.
Fav Blogs: Doug Cole here , C.R. Rice's here, & Hans Christian Vortisch here.
safisher is offline   Reply With Quote
Old 08-25-2015, 08:45 PM   #20
Anthony
 
Join Date: Feb 2005
Location: Berkeley, CA
Default Re: [Spaceships] Heat Signature, Cloaking Device, and Stealth Hull

Quote:
Originally Posted by safisher View Post
A couple of thoughts here. First, in the "realistic" approach, we have just begun to tip our toes into metamaterials.
Which are completely irrelevant to the problem of stealth in space. At most, it gives options for reducing the reflected signature of a ship.
Quote:
Originally Posted by safisher View Post
Everyone now screaming that "there is no stealth in space" assumes that everything works in the far future as we now understand it.
We're assuming thermodynamics is true.
__________________
My GURPS site and Blog.
Anthony is offline   Reply With Quote
Reply

Tags
cloaking device, detection, heat signature, spaceships, stealth hull

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Fnords are Off
[IMG] code is Off
HTML code is Off

Forum Jump


All times are GMT -6. The time now is 05:39 AM.


Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2024, vBulletin Solutions, Inc.