The Rancor Pit Forum Index
Welcome to The Rancor Pit forums!

The Rancor Pit Forum Index
FAQ   ::   Search   ::   Memberlist   ::   Usergroups   ::   Register   ::   Profile   ::   Log in to check your private messages   ::   Log in

Cloaking Devices = SWU Submarines?
Post new topic   Reply to topic    The Rancor Pit Forum Index -> Ships, Vehicles, Equipment, and Tech -> Cloaking Devices = SWU Submarines? Goto page Previous  1, 2, 3, 4  Next
View previous topic :: View next topic  
Author Message
CRMcNeill
Director of Engineering
Director of Engineering


Joined: 05 Apr 2010
Posts: 11762
Location: Redding System, California Sector, on the I-5 Hyperspace Route.

PostPosted: Sun Aug 12, 2018 9:06 pm    Post subject: Reply with quote

Pel wrote:
The CGT is a precision instrument specifically meant to detect cloaked ships by their mass.

That's incorrect. By it's own description in the SW Sourcebook, the CGT is a common (and expensive) type of sensor that detects gravitic field fluctuations. Nowhere in its description does it state that it was specifically designed as a counter to cloaking devices.

What it does say is that "high quality CGTs can detect and identify any fluctuations in the gravity field for hundreds of thousands of kilometers around." That phrasing opens the door to a range of different "grades" of CGT array, with the highest quality being able to provide Capital or Death Star grade sensor coverage, while the lowest quality provides basic directional and strength detection for the automated systems on hyperdrives.


Quote:
The hyperdrive cut-out probably works on similar principles, but IMO it looks for big mass shadows (planets, large ships, heavy asteroids, etc.). Also, it's just a cut-out, a safety override for the hyperdrive that dumps you into normal space upon detecting a potential collision with a mass shadow. The cut-out probably doesn't give bearing and distance to the shadow, it just trips when it senses one.

It has to work on a similar principle, because the only known method of bringing a ship out of hyperspace is to trick it by projecting a gravity well in its path. This in turn requires that the ship has some method of detecting gravity fields, even if just an omni-directional sensor that just detects gravity strength.

Quote:
Equating the two is ingenious, but for the purposes of the game I'd say it's most likely impractical as the two systems (fire control and hyperdrive) were never meant to work together

You're skipping a step. CGTs are a common type of sensor, not fire control. I'm not thinking in terms of fire control right now so much as I'm thinking in terms of a sensor that can function as the SWU equivalent of sonar. Fire Control comes later.
_________________
"No set of rules can cover every situation. It's expected that you will make up new rules to suit the needs of your game." - The Star Wars Roleplaying Game, 2R&E, pg. 69, WEG, 1996.

The CRMcNeill Stat/Rule Index


Last edited by CRMcNeill on Mon Aug 13, 2018 12:55 pm; edited 1 time in total
Back to top
View user's profile Send private message Send e-mail Visit poster's website
Whill
Supreme Chancellor (Owner/Admin)


Joined: 14 Apr 2008
Posts: 5229
Location: Columbus, OHIO, USA, Earth, The Solar System, The Milky Way Galaxy

PostPosted: Sun Aug 12, 2018 10:19 pm    Post subject: Reply with quote

CRMcNeill wrote:
What it does say is that "high quality CGTs can detect and identify any fluctuations in the gravity field for hundreds of thousands of kilometers around." That phrasing opens the door to a range of different "grades" of CGT array, with the highest quality being able to provide Capital or Death Star grade sensor coverage, while the lowest quality provides basic directional and strength detection for the automated systems on hyperdrives.

Basic?! The automated systems on hyperdrives would need the highest quality there is because even a ship plodding along at an extremely low speed through hyperspace of only 3c is traveling about 900,000 km per second. But even if hyperdrive cut-outs take less than a second to work, with the vast distances covered the math works out to ships traveling though hyperspace at thousands of times the speed of light, so they would need to sense gravity much further ahead than hundreds of thousands of km to activate a hyperdrive cut-out.

Unless you're saying that "basic" is only a single direction (forward in the path of the ship), and it is the "around" that makes it a higher quality? Or sensing gravity fields is much easier in hyperspace than in realspace?
_________________
*
Site Map
Forum Guidelines
Registration & Log-In Help
Back to top
View user's profile Send private message Visit poster's website
CRMcNeill
Director of Engineering
Director of Engineering


Joined: 05 Apr 2010
Posts: 11762
Location: Redding System, California Sector, on the I-5 Hyperspace Route.

PostPosted: Sun Aug 12, 2018 11:11 pm    Post subject: Reply with quote

Whill wrote:
Basic?! The automated systems on hyperdrives would need the highest quality there is because even a ship plodding along at an extremely low speed through hyperspace of only 3c is traveling about 900,000 km per second. But even if hyperdrive cut-outs take less than a second to work, with the vast distances covered the math works out to ships traveling though hyperspace at thousands of times the speed of light, so they would need to sense gravity much further ahead than hundreds of thousands of km to activate a hyperdrive cut-out.

My thinking is that, much like how distances and speeds are "compressed" (for lack of a better word) in hyperspace, gravity fields are detectable at greater distances if the detecting ship is in hyperspace. This ties in with my theory about gravity having a much stronger effect in hyperspace, with the ability to actually throw a ship slightly off course if it attempts a hyperspace jump too far inside a gravity well.

Quote:
Unless you're saying that "basic" is only a single direction (forward in the path of the ship), and it is the "around" that makes it a higher quality? Or sensing gravity fields is much easier in hyperspace than in realspace?

Yes, that's what I mean by basic, in that the high-end CGT arrays as described by Zahn are composed of multiple, interlinked CGTs connected to a central processing unit, and are capable of precisely locating even cloaked objects. The low-end version on a hyperdrive would be effectively limited to direction and strength of gravity field.
_________________
"No set of rules can cover every situation. It's expected that you will make up new rules to suit the needs of your game." - The Star Wars Roleplaying Game, 2R&E, pg. 69, WEG, 1996.

The CRMcNeill Stat/Rule Index
Back to top
View user's profile Send private message Send e-mail Visit poster's website
Pel
Line Captain
Line Captain


Joined: 10 May 2006
Posts: 812
Location: Texas

PostPosted: Mon Aug 13, 2018 12:16 pm    Post subject: Reply with quote

Ok, so the CGT is actually a complex array (probably 3 or 4 dimensional) of the basic hyperdrive cut-out sensors. That's pretty clever.

I'm having flashbacks to sonar triangulation. If we held a contact on both the bow array and the towed array (pulled several hundred feet behind the boat) we could get a much quicker and more accurate firing solution to the target than by simply plotting from a single sensor source (either the bow or towed array), because the two sensors were physically separated and both provided bearings to the contact. Where those bearing lines converged quickly resolved into the target's location.

Transplanting that into a Star Wars setting, maybe the individual sensors in a CGT array need some physical separation to operate and can then provide a quick and accurate target solution (which would be why they're mounted on large ships).

With a single passive sensor you can eventually get an accurate solution, but it takes time, some maneuvering, and a bit of trig, during which time the other guy is doing the same if he knows you're there. You don't need a perfect targeting solution on the other guy, but the better it is, the more likely you'll launch your torpedoes in the right direction. Smile
_________________
Aha!
Back to top
View user's profile Send private message
CRMcNeill
Director of Engineering
Director of Engineering


Joined: 05 Apr 2010
Posts: 11762
Location: Redding System, California Sector, on the I-5 Hyperspace Route.

PostPosted: Mon Aug 13, 2018 9:16 pm    Post subject: Reply with quote

Pel wrote:
Ok, so the CGT is actually a complex array (probably 3 or 4 dimensional) of the basic hyperdrive cut-out sensors. That's pretty clever.

I picture the ultimate expression of the CGT being the CGT Array mentioned in the HttE trilogy. For whatever reason, Zahn didn't just use the basic CGT, and I think it was a smart choice. I picture a CGT Array as similar to the SOSUS net hydrophones placed on the ocean floor in the Atlantic as part of NATO's anti-submarine strategy against the Warsaw Pact during the Cold War: a stand-alone, complex array composed of multiple high-end CGTs, so that multiple layers of precision allow for pinpoint triangulation on gravitic anomalies.

There would also be varying degrees of individual CGTs mounted aboard ships, likely more than one, allowing for a much more basic detection capability as part of an overall sensor suite.

Quote:
I'm having flashbacks to sonar triangulation. If we held a contact on both the bow array and the towed array (pulled several hundred feet behind the boat) we could get a much quicker and more accurate firing solution to the target than by simply plotting from a single sensor source (either the bow or towed array), because the two sensors were physically separated and both provided bearings to the contact. Where those bearing lines converged quickly resolved into the target's location.

I've been playing some Cold Waters (a homage to the old Red Storm Rising sub simulator), and it does something similar. Personally, though, I'm not prepared to go into that degree of crunch for the system that we have. I'd probably just find some way to work it into the existing sensor rules somehow.

Quote:
Transplanting that into a Star Wars setting, maybe the individual sensors in a CGT array need some physical separation to operate and can then provide a quick and accurate target solution (which would be why they're mounted on large ships).

My concept of SWU sensors is of multiple, overlapping sensors scattered across the exterior of the ship, with one main array ala the Falcon or the nose sensor pack on the X-Wing, so having multiple CGT sensors placed at various locations on the ship to allow for triangulation is an easy step.

Quote:
With a single passive sensor you can eventually get an accurate solution, but it takes time, some maneuvering, and a bit of trig, during which time the other guy is doing the same if he knows you're there. You don't need a perfect targeting solution on the other guy, but the better it is, the more likely you'll launch your torpedoes in the right direction. Smile

I'm picturing the WW2 submarine warfare model, with unguided torpedoes and depth bombs (seismic charges), so any analog of sub vs. sub warfare would be pretty rare, and more confined to at least one of the two operating uncloaked,
_________________
"No set of rules can cover every situation. It's expected that you will make up new rules to suit the needs of your game." - The Star Wars Roleplaying Game, 2R&E, pg. 69, WEG, 1996.

The CRMcNeill Stat/Rule Index
Back to top
View user's profile Send private message Send e-mail Visit poster's website
CRMcNeill
Director of Engineering
Director of Engineering


Joined: 05 Apr 2010
Posts: 11762
Location: Redding System, California Sector, on the I-5 Hyperspace Route.

PostPosted: Mon Aug 13, 2018 9:49 pm    Post subject: Reply with quote

Incidentally, my concept of a SUDAR sensor is firming up a little. In the OP, I posited an active subspace pulse generator that sends an omni-directional pulse of subspace energy, which then generates a return pulse back, much like an active sonar system.

I later proposed something similar as a description for subspace radio, co-opting some of the technobabble for gravitics from the Honor Harrington series. Put simply, subspace transmissions are redirected and propagated across the "upper" dimensional barrier between realspace and hyperspace. They don't actually make it into hyperspace, but are instead reflected back "down" and "outward" in all directions.

This theory was given some official cover by an offhand reference in the description of the Hyperwave Signal Interceptor (a common sensor system) which I referenced here.

So, combining all of this, my theory is that the SUDAR system generates a subspace pulse in all directions, which encounters solid objects (i.e. anything with a readable mass) and briefly increases an object's gravity field fluctuations, which is in turn detected by the CGT array.
_________________
"No set of rules can cover every situation. It's expected that you will make up new rules to suit the needs of your game." - The Star Wars Roleplaying Game, 2R&E, pg. 69, WEG, 1996.

The CRMcNeill Stat/Rule Index
Back to top
View user's profile Send private message Send e-mail Visit poster's website
Raven Redstar
Rear Admiral
Rear Admiral


Joined: 10 Mar 2009
Posts: 2115
Location: Pullman, WA

PostPosted: Mon Aug 13, 2018 9:51 pm    Post subject: Reply with quote

So does that mean that SUDAR can defeat a cloaked ship running full 'submerge' cloak?
_________________
RR
________________________________________________________________
Back to top
View user's profile Send private message
CRMcNeill
Director of Engineering
Director of Engineering


Joined: 05 Apr 2010
Posts: 11762
Location: Redding System, California Sector, on the I-5 Hyperspace Route.

PostPosted: Mon Aug 13, 2018 10:07 pm    Post subject: Reply with quote

Raven Redstar wrote:
So does that mean that SUDAR can defeat a cloaked ship running full 'submerge' cloak?

Yes, in much the same way that SONAR can detect a submerged submarine, even though radar and visual spotting would be completely ineffective. Of course, not every ship would be equipped with a full-up SUDAR system, mostly just escort warships (corvettes, frigates and some cruisers).
_________________
"No set of rules can cover every situation. It's expected that you will make up new rules to suit the needs of your game." - The Star Wars Roleplaying Game, 2R&E, pg. 69, WEG, 1996.

The CRMcNeill Stat/Rule Index
Back to top
View user's profile Send private message Send e-mail Visit poster's website
Raven Redstar
Rear Admiral
Rear Admiral


Joined: 10 Mar 2009
Posts: 2115
Location: Pullman, WA

PostPosted: Mon Aug 13, 2018 10:47 pm    Post subject: Reply with quote

So it would give a reason for ISDs to have smaller escort ships travelling around with them, or do you think ISDs would be equipped with them?
_________________
RR
________________________________________________________________
Back to top
View user's profile Send private message
CRMcNeill
Director of Engineering
Director of Engineering


Joined: 05 Apr 2010
Posts: 11762
Location: Redding System, California Sector, on the I-5 Hyperspace Route.

PostPosted: Mon Aug 13, 2018 11:14 pm    Post subject: Reply with quote

Raven Redstar wrote:
So it would give a reason for ISDs to have smaller escort ships travelling around with them, or do you think ISDs would be equipped with them?

I could go either way, honestly. In the films, we see ISDs operating almost exclusively without escort, so if I get this idea fully thought out, it's not unreasonable that an ISD would be equipped with SUDAR systems. On the other hand, a system analogous to WW2 anti-submarine warfare would place the burden of such combat on smaller ships. Of course, it's highly likely that the larger ships in the SWU would also be more likely to be equipped with the more capable CGT sensors. What occurs to me initially is a possible rule that the mass of a larger ship interferes with the effectiveness of the subspace pulse generated by the SUDAR.
_________________
"No set of rules can cover every situation. It's expected that you will make up new rules to suit the needs of your game." - The Star Wars Roleplaying Game, 2R&E, pg. 69, WEG, 1996.

The CRMcNeill Stat/Rule Index
Back to top
View user's profile Send private message Send e-mail Visit poster's website
Raven Redstar
Rear Admiral
Rear Admiral


Joined: 10 Mar 2009
Posts: 2115
Location: Pullman, WA

PostPosted: Tue Aug 14, 2018 12:11 am    Post subject: Reply with quote

True.
But, from what we see in TESB it seems that even if an ISD did have a SUDAR system, the captain may be arrogant enough to assume that "a ship that small doesn't have a cloaking device".

The SUDAR ping may not be able to differentiate the cloaked ship if it's close enough to an object of greater mass: like the Falcon attached to the side of the ISD or if the ship landed on an asteroid or moon. This is analogous to what we see in some submarine movies where the captain sets the sub down on the ocean floor to avoid detection. Such a move with a double-blind cloak could be risky!
_________________
RR
________________________________________________________________
Back to top
View user's profile Send private message
Zarn
Captain
Captain


Joined: 17 Jun 2014
Posts: 679
Location: Norway

PostPosted: Tue Aug 14, 2018 2:06 am    Post subject: Reply with quote

There's the TIE /fc concept that might be upgraded to some sort of TIE Scimitar /fc or TIE Bomber /fc for sensor platforms.

I'm wondering whether nebulae (such as the Starcave of ThonBoka) could play havoc with such cutout sensors (and by extension make it hard to find anything that's cloaked - or even find it on sensors at all), and then there's the new interpretation of The Maw in Solo that would also be, let's call it Difficult Terrain for sensors. Or, for that matter, Achtnak Turbine Station in the top layers of a gas giant.

If you're passively cloaked, lying doggo trailing something like a comet or a gas giant's moon - unless someone sees a wake through a ring system or in the upper layers of a gas giant, you should be pretty much more quiet than a space rock zooming past.
Back to top
View user's profile Send private message
Pel
Line Captain
Line Captain


Joined: 10 May 2006
Posts: 812
Location: Texas

PostPosted: Tue Aug 14, 2018 1:00 pm    Post subject: Reply with quote

Even CGTs may not detect a vessel hiding in a large mass shadow so nothing is foolproof.

I think the bigger problem will be getting close enough to launch your weapons with a decent chance of impact. Just thumbing through the various sourcebooks, I notice both proton torpedo and concussion missile ranges top out at 7 while typical Scan ranges (that's the basic active sweep) for small capital ships are in the 75-80 range. That's an awful lot of distance to cover, probably at slow speeds, under the watchful eyes of Imperial Sensor Techs and their droid assistants. I think sensors become more effective at medium and close ranges, so you're talking about a pretty hairy situation trying to sneak up on one of these ships.

Also, don't forget that your target is under way and maneuvering. No combat vessel remains stationary because it's just harder to hit a moving target and they probably have somewhere to be (patrolling an area, advancing toward a battle zone, delivering troops & supplies, etc.). If you're stealth ship is creeping along at 2 or 3 (just how far IS a space unit, anyway?) and your target's moving at a sedate speed of 5, you won't catch it.

The WWII boats were in an identical situation. They were never faster submerged than their surface targets so they would sprint over the horizon, parallel the target's base course, and race to get into a firing position in front of them, then submerge at the first sign of the enemy and lie in wait close enough (often no more than 1000 yards or 1/2 mile) from the target's projected course.

One last thing: when you do light off your weapons, it's going to trip every sensor and alarm on the target vessel. Has anyone ever worked out speeds for SW missile weapons? If you fire at maximum range, will the torpedoes/missiles reach the target in one round? If so, are the published ranges way too short? That's a different topic, but it should color the discussion of sensors and detection.
_________________
Aha!
Back to top
View user's profile Send private message
CRMcNeill
Director of Engineering
Director of Engineering


Joined: 05 Apr 2010
Posts: 11762
Location: Redding System, California Sector, on the I-5 Hyperspace Route.

PostPosted: Tue Aug 14, 2018 5:16 pm    Post subject: Reply with quote

Pel wrote:
Even CGTs may not detect a vessel hiding in a large mass shadow so nothing is foolproof.

There is mention in the SWSB of ships being able to hide from CGT arrays, as well as real-world stories of subs hiding from sonar in shallow water or near other, larger ships, so this would make sense.

Quote:
I think the bigger problem will be getting close enough to launch your weapons with a decent chance of impact. Just thumbing through the various sourcebooks, I notice both proton torpedo and concussion missile ranges top out at 7 while typical Scan ranges (that's the basic active sweep) for small capital ships are in the 75-80 range. That's an awful lot of distance to cover, probably at slow speeds, under the watchful eyes of Imperial Sensor Techs and their droid assistants. I think sensors become more effective at medium and close ranges, so you're talking about a pretty hairy situation trying to sneak up on one of these ships.

I'm thinking in terms of a large, dual-stage torpedo that uses some sort of baffled drive system to get in close (within 5-7 units), then fires the second stage (a standard proton torpedo). Again, I haven't really worked out the details for this (focusing primarily on the Cloak at the moment), but the basic premise is that the cloaked ship waits several rounds to generate a rough estimate of where the target will be, then fires the torpedo "into the basket" so to speak.

Of course, I've always felt that the WEG stats for missiles and torpedoes were woefully under-ranged, and I addressed that in my various stat re-writes, where the Capital-Scale Proton Torpedo Launcher has a maximum range of 30 SUs.

So there are options. I'm not committing to anything at the moment, since I'm trying to address the cloak first.

Quote:
Also, don't forget that your target is under way and maneuvering. No combat vessel remains stationary because it's just harder to hit a moving target and they probably have somewhere to be (patrolling an area, advancing toward a battle zone, delivering troops & supplies, etc.). If you're stealth ship is creeping along at 2 or 3 (just how far IS a space unit, anyway?) and your target's moving at a sedate speed of 5, you won't catch it.

The WWII boats were in an identical situation. They were never faster submerged than their surface targets so they would sprint over the horizon, parallel the target's base course, and race to get into a firing position in front of them, then submerge at the first sign of the enemy and lie in wait close enough (often no more than 1000 yards or 1/2 mile) from the target's projected course.

A Space Unit is as far as needs to be for the purposes of the plot. Don't try to overthink it, as applying an actual distance value to an SU causes more problems than it solves.

WWII sub tactics are also applicable in this scenario in the SWU. Ship captains would look for convoys or taskforces in cruising formation (i.e. on predictable, non-evasive courses), work their way into position and fire torpedoes on the angle most likely to generate a hit, so long as the target in question doesn't suddenly change direction

Quote:
One last thing: when you do light off your weapons, it's going to trip every sensor and alarm on the target vessel. Has anyone ever worked out speeds for SW missile weapons? If you fire at maximum range, will the torpedoes/missiles reach the target in one round? If so, are the published ranges way too short? That's a different topic, but it should color the discussion of sensors and detection.

The theory I'm working with right now is that cloaked ships are limited to projectile weapons, due to both power consumption issues and charged energy causing major disruption of the cloak field itself.

It's all quite a ways from being finalized, but I suddenly found myself with a lot of free time on my hands, so I'm looking for something to keep me occupied.
_________________
"No set of rules can cover every situation. It's expected that you will make up new rules to suit the needs of your game." - The Star Wars Roleplaying Game, 2R&E, pg. 69, WEG, 1996.

The CRMcNeill Stat/Rule Index
Back to top
View user's profile Send private message Send e-mail Visit poster's website
CRMcNeill
Director of Engineering
Director of Engineering


Joined: 05 Apr 2010
Posts: 11762
Location: Redding System, California Sector, on the I-5 Hyperspace Route.

PostPosted: Wed Aug 15, 2018 11:04 am    Post subject: Reply with quote

Something I neglected to include in my OP was the concept that the cloaking device used the same emitters as the ship's shields, and thus a ship could only use one or the other at a time. This helps to simulate the vulnerability to damage of a sub while submerged.
_________________
"No set of rules can cover every situation. It's expected that you will make up new rules to suit the needs of your game." - The Star Wars Roleplaying Game, 2R&E, pg. 69, WEG, 1996.

The CRMcNeill Stat/Rule Index
Back to top
View user's profile Send private message Send e-mail Visit poster's website
Display posts from previous:   
Post new topic   Reply to topic    The Rancor Pit Forum Index -> Ships, Vehicles, Equipment, and Tech All times are GMT - 5 Hours
Goto page Previous  1, 2, 3, 4  Next
Page 3 of 4

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © 2001, 2005 phpBB Group


v2.0