Sensors Vs Superior Stealth
Sensors Vs Superior Stealth
Just started running Drinax.
On their first try at piracy, they came upon a Far Trader. It was during that that I realised, their superior stealth was giving the total of -9 (-6 standard and -3 for TL difference), which the meant it was impossible for the Far Tarder to ever spot them. I tried to find rules for sensor bonuses based of distance, but couldn't find anything. Is the intent that the Harrier can sneak up and dock without ever been seen, or am I missing something?
On their first try at piracy, they came upon a Far Trader. It was during that that I realised, their superior stealth was giving the total of -9 (-6 standard and -3 for TL difference), which the meant it was impossible for the Far Tarder to ever spot them. I tried to find rules for sensor bonuses based of distance, but couldn't find anything. Is the intent that the Harrier can sneak up and dock without ever been seen, or am I missing something?
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- Cosmic Mongoose
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Re: Sensors Vs Superior Stealth
That is correct.
A Free Trader doesn't have very good sensors, so unless it has a very good sensor operator it can't see much.
The only range effect is that sensor tasks are more difficult at Very Distant range.
A Free Trader doesn't have very good sensors, so unless it has a very good sensor operator it can't see much.
The only range effect is that sensor tasks are more difficult at Very Distant range.
Re: Sensors Vs Superior Stealth
As well as having good skill, if your sensor operator(s) has a reason to be actively searching, they can Go Slower to gain bonuses or possibly Task Chain with good reason.
The point of the stealth feature is make your targets very vulnerable. Non-warships have a hard time with normal ships alone. Ships purposely build with very expensive stealth and EAG are meant to overwhelm most normal vessels and make warships with better capabilities struggle. However, you piss off the wrong people by getting over confident, you might find a pirate hunting squadron normally looking for enemy stealthed ships dogging you. One ship in the group could have Improved Signal Processing or Enhanced Signal Processing, Distributed or Extended Arrays plus maybe the Extension Net. Add in a few specialized SOs and you might want to lay low if you get away or at least change tactics.
This is why I rebuilt the Corsair. Nothing better than having guns bearing on your prey at Adjacent to Short range then communications announce 'Heave to and deliver!".
The point of the stealth feature is make your targets very vulnerable. Non-warships have a hard time with normal ships alone. Ships purposely build with very expensive stealth and EAG are meant to overwhelm most normal vessels and make warships with better capabilities struggle. However, you piss off the wrong people by getting over confident, you might find a pirate hunting squadron normally looking for enemy stealthed ships dogging you. One ship in the group could have Improved Signal Processing or Enhanced Signal Processing, Distributed or Extended Arrays plus maybe the Extension Net. Add in a few specialized SOs and you might want to lay low if you get away or at least change tactics.
This is why I rebuilt the Corsair. Nothing better than having guns bearing on your prey at Adjacent to Short range then communications announce 'Heave to and deliver!".
Re: Sensors Vs Superior Stealth
Awesome, thanks guys
Re: Sensors Vs Superior Stealth
I’d also allow a recon check to visually identify the Harrier so they may get a chance to spot it at the last minute.
Re: Sensors Vs Superior Stealth
I'm still inclined to give a bonus to sensors checks at short range. If the targetting systems on weapons are affected by range, then to my (admittedly completed unqualified) mind it seems like sensor checks ought to be.
But even just from a game balance point of view, given the advantages that are gained from being at short range (bonus to hit, more detail information gained on the scan), it seems reasonable that they should come with a bit more risk of detection.
BTW, something I often overlook is that the target gets also gets a +2 bonus if it is being scanned by active radar.
Dan.
But even just from a game balance point of view, given the advantages that are gained from being at short range (bonus to hit, more detail information gained on the scan), it seems reasonable that they should come with a bit more risk of detection.
BTW, something I often overlook is that the target gets also gets a +2 bonus if it is being scanned by active radar.
Dan.
Re: Sensors Vs Superior Stealth
Yes, this. IMTU Civilian sensors have Long range and a scan is a Difficult task. Each range band closer is one level easier (so Short range is Routine) and each band farther is one level harder. Your Effect can allow you more detail than normal if you score high enough (2+ points of Effect allows the next higher level of detail).
You can upgrade to longer ranges for a cost (Military sensors are Difficult at Very Long for example) or save some money and install weaker ones (Basic sensors are Difficult at Medium). So you can have Very Long range Civilian sensors for +50% in cost. I don’t use the RAW DMs based on sensor types.
I also do similar with energy weapons - DM+1 to hit for each band closer than effective range, DM-2 for each band beyond. With the resultant increase in Effect also upping damage at nearer ranges. So a Medium range Beam Laser looks like this:
Adj DM+3
Close DM+2
Short DM+1
Med DM+0
Long DM-2
VLong DM-4
etc
This applies to lasers, plasma, fusion, particle, ion and tachyon weapons. So a Particle Barbette does 4D+4 at Close, 4D-2 at Distant.
Re: Sensors Vs Superior Stealth
By the time most targets are attempting sensor check at Short or less, the first thing they see is a ship often better armed than them and any thought to use speed and distance to escape will be funny.
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- Warlord Mongoose
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Re: Sensors Vs Superior Stealth
The real difference should be the operator or the readiness status of the bridge.
Between routine operations and looking for an anomaly.
Between routine operations and looking for an anomaly.
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- Cosmic Mongoose
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Re: Sensors Vs Superior Stealth
One thing that you should do is continue to extend the Sensors above TL12, increasing the Sensor DM by one at each TL. That helps the sensors keep up with advanced stealth and gives higher tech military ships a fighting chance against super-stealth. This Stealth/Sensor battle should be one of the "wars" in ship design as TL increases. Just like the fight between weapons that cause more damage and armor/shields, sensors and stealth will be an on-going back-and-forth in designs/capability. As soon as a new form of stealth is developed, then the sensor designers will begin working on ways to defeat it. Once defeated, then the stealth people will figure out a new way to defeat the new sensors.
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Re: Sensors Vs Superior Stealth
Actually that's already built in.
"with an additional DM-1 for every Tech Level the ship is higher than the sensors trying to locate it."
As the Tech Level of a target ship's sensors increases, the easier to detect a stealthed ship.
"with an additional DM-1 for every Tech Level the ship is higher than the sensors trying to locate it."
As the Tech Level of a target ship's sensors increases, the easier to detect a stealthed ship.
Re: Sensors Vs Superior Stealth
This came up in the small craft topic (viewtopic.php?f=89&t=121539) and I'm migrating a related question here:
Let's say you're a patrol corvette or a close escort and you have detected the Harrier in close, short, or maybe even medium range, when might you lose track of it? When it gets to long range as it burns its 6G maneuver drive to get away, does its stealth and countermeasures suddenly make it invisible?
Let's say you're a patrol corvette or a close escort and you have detected the Harrier in close, short, or maybe even medium range, when might you lose track of it? When it gets to long range as it burns its 6G maneuver drive to get away, does its stealth and countermeasures suddenly make it invisible?
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Re: Sensors Vs Superior Stealth
Adding to that - does the act of engaging its m-drive make it easier or harder to detect?
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- Cosmic Mongoose
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Re: Sensors Vs Superior Stealth
I am using Energy Points for IR signature: 100 or less = DM-2 to detect/track, 500+ = DM+2 to detect/track. So nominally not really affecting the game but gives a bit of verisimilitude and my players can “run silent” by shutting down various systems and drifting until the last possible moment, which they absolutely love.
We’ve also adopted AnotherDilbert’s house rule of allowing a sensor check at each range band change - the Ref giveth, and the Ref taketh away
Thank you for that cool idea.
Good point about crew readiness. Could be a good way to turn the tables occasionally.
We’ve also adopted AnotherDilbert’s house rule of allowing a sensor check at each range band change - the Ref giveth, and the Ref taketh away

Good point about crew readiness. Could be a good way to turn the tables occasionally.
Re: Sensors Vs Superior Stealth
Excellent ideas all! Thanks, guys! I think the way I'll do it is similar to yours, NOLATrav. Once detected, ridding yourself of a detecting ship requires advancement to the next range band (thus inducing a new check) and energy usage as a positive or negative effect. This adds a new tactical consideration as well, a nice new wrinkle for space combat.
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- Greater Spotted Mongoose
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Re: Sensors Vs Superior Stealth
Just remember that the sensor suites have a number of different scans, such as the EM which can detect onboard systems of which the M-drive is rather high power usage.
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- Warlord Mongoose
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Re: Sensors Vs Superior Stealth
I view stealth as a sort of overall attribute, so the ship designers would have accounted for most forms of usual radiation emission, including propulsion.
Not quite sure how to mask a fusion rocket going off, though, maybe half the modifier?
Not quite sure how to mask a fusion rocket going off, though, maybe half the modifier?
Re: Sensors Vs Superior Stealth
You could base the modifier on level of thrust. But unless you have a way of muting the thermal signature I would expect the exhaust to be very noticeable.
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- Greater Spotted Mongoose
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Re: Sensors Vs Superior Stealth
Or could use the boon / bane system.
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