Need a quick ruling - missile countermeasures

The only software that benefits missiles / torpedoes is the Launch Solution package, the missile salvo itself is used for gunner skill check not the gunners.
 
Self guided missiles shouldn't need any of that. They are essentially fire and forget. Though they should be fed the target information and a lock prior to launch.
 
Late to this discussion.

Electronic Countermeasures should be working all the time. Phases in a game mechanic will mess this up, but the ECM is always working. If the jamming is DRFM, the 'target' isn't where the missiles are launched at. If the missiles are guided into the false target, at spatial ranges, they miss by 100's of kms. If they are self-guided, they are still messed up, but may be able to hit the target, if they are 'smart' enough. Any -TL difference they should miss.

Digital Radio Frequency Memory (DRFM) is an electronic method for digitally capturing and retransmitting RF signals. DRFM systems are typically used in radar jamming, although applications in cellular communications are becoming more common.

A DRFM system is designed to digitize an incoming RF input signal at a frequency and bandwidth necessary to adequately represent the signal, then reconstruct that RF signal when required. The most significant aspect of DRFM is that as a digital "duplicate" of the received signal, it is coherent with the source of the received signal. As opposed to analog "memory loops", there is no signal degradation caused by continuously cycling the energy through a front-end amplifier which allows for greater range errors for reactive jamming and allows for predictive jamming. A DRFM system may modify the signal prior to retransmitting which can alter the signature of the false target; adjusting its apparent radar cross section, range, velocity, and angle. DRFMs present a significant obstacle for radar sensors.

Source: https://en.wikipedia.org/wiki/Digital_radio_frequency_memory
 
Yes, if TL12-15 guidance systems are similar to TL8 guidance systems, they won't be that great at futuristic space combat.

You have to make the leap of faith that technology improves on both sides of the equation to make the game playable. Possibly missiles won't even be a thing in the future because giving them the ability to maneuver and target at space ranges proves impossible. But something will exist that works. Much easier to keep something that people today generally grasp and assume future tech keeps it functional.
 
ECM should not be active all the time for a few reasons. First is that it would
Late to this discussion.

Electronic Countermeasures should be working all the time. Phases in a game mechanic will mess this up, but the ECM is always working. If the jamming is DRFM, the 'target' isn't where the missiles are launched at. If the missiles are guided into the false target, at spatial ranges, they miss by 100's of kms. If they are self-guided, they are still messed up, but may be able to hit the target, if they are 'smart' enough. Any -TL difference they should miss.

Digital Radio Frequency Memory (DRFM) is an electronic method for digitally capturing and retransmitting RF signals. DRFM systems are typically used in radar jamming, although applications in cellular communications are becoming more common.

A DRFM system is designed to digitize an incoming RF input signal at a frequency and bandwidth necessary to adequately represent the signal, then reconstruct that RF signal when required. The most significant aspect of DRFM is that as a digital "duplicate" of the received signal, it is coherent with the source of the received signal. As opposed to analog "memory loops", there is no signal degradation caused by continuously cycling the energy through a front-end amplifier which allows for greater range errors for reactive jamming and allows for predictive jamming. A DRFM system may modify the signal prior to retransmitting which can alter the signature of the false target; adjusting its apparent radar cross section, range, velocity, and angle. DRFMs present a significant obstacle for radar sensors.

Source: https://en.wikipedia.org/wiki/Digital_radio_frequency_memory
It would be very odd to see ECM systems being active all the time for a variety of reasons. First it would be disruptive to regular sensors and heavily frowned upon/prohibited by authorities as a risk to regular civilian traffic. Secondly it would put more strain on the ships systems than expected (the same reason why they don't leave radars/emitters on all the time today is that the components have a finite life to them - 52nd century systems break down as much as everything else since you have the annual maintenance of a ship that assumes normal operations). Thirdly by having your systems active all the time it would give your enemies a regular image of the emissions, which means it would make it that much easier to defeat when you actually needed them.

These are the rules we see today with active emitters and even though the tech would be more efficient and powerful, the basic fundamentals don't really change that much. Of course we could simply wave a hand and say "it's the future, it's perfect", but that seems like an unreasonable expectation.
 
ECM should not be active all the time for a few reasons. First is that it would

It would be very odd to see ECM systems being active all the time for a variety of reasons. First it would be disruptive to regular sensors and heavily frowned upon/prohibited by authorities as a risk to regular civilian traffic. Secondly it would put more strain on the ships systems than expected (the same reason why they don't leave radars/emitters on all the time today is that the components have a finite life to them - 52nd century systems break down as much as everything else since you have the annual maintenance of a ship that assumes normal operations). Thirdly by having your systems active all the time it would give your enemies a regular image of the emissions, which means it would make it that much easier to defeat when you actually needed them.

These are the rules we see today with active emitters and even though the tech would be more efficient and powerful, the basic fundamentals don't really change that much. Of course we could simply wave a hand and say "it's the future, it's perfect", but that seems like an unreasonable expectation.
ECM systems don't run "all the time", but in combat situations, with missiles and beams in use, I'd want all the viable systems working. No, the ECM system may not be active and transmitting all the time in combat, either. However, with active seeking missiles closing, yes, that system would be on and transmitting, jamming as if its life depended on it. Within the Game Mechanics, saying you have a finite phase in which to perform a function isn't necessarily realistic.
EG: ECM happens in this phase, missiles do their thing in this other phase, ECM can't affect the missile because it isn't in the right phase.

My TU: ECM is activated in the ECM phase, or not. During the Missile phase, if the ECM system is on, the ECM affects the missile. (Hence my statement: ECM is on all the time.)
 
ECM systems don't run "all the time", but in combat situations, with missiles and beams in use, I'd want all the viable systems working. No, the ECM system may not be active and transmitting all the time in combat, either. However, with active seeking missiles closing, yes, that system would be on and transmitting, jamming as if its life depended on it. Within the Game Mechanics, saying you have a finite phase in which to perform a function isn't necessarily realistic.
EG: ECM happens in this phase, missiles do their thing in this other phase, ECM can't affect the missile because it isn't in the right phase.

My TU: ECM is activated in the ECM phase, or not. During the Missile phase, if the ECM system is on, the ECM affects the missile. (Hence my statement: ECM is on all the time.)
Ok, I misunderstood you - I had read that literally to mean ECM is just plain ON. I agree that ECM would be active during combat - from the start of the engagement to the end of the engagement.

This is the point where it gets a bit messy in gaming mechanics. A good ECM operator will gain knowledge during the engagement between incoming salvo's and possibly could use that information to better their systems response to future incoming fire. At the same time enemy operators can gain knowledge of the enemy and update their missile profiles to adapt/ignore what they have seen. While writers and reality can adjust to such things, gaming mechanics don't do so well. It's far easier to just have initial adjustments and let the dice roll where they may.
 
ECM systems don't run "all the time", but in combat situations, with missiles and beams in use, I'd want all the viable systems working. No, the ECM system may not be active and transmitting all the time in combat, either. However, with active seeking missiles closing, yes, that system would be on and transmitting, jamming as if its life depended on it. Within the Game Mechanics, saying you have a finite phase in which to perform a function isn't necessarily realistic.
EG: ECM happens in this phase, missiles do their thing in this other phase, ECM can't affect the missile because it isn't in the right phase.

My TU: ECM is activated in the ECM phase, or not. During the Missile phase, if the ECM system is on, the ECM affects the missile. (Hence my statement: ECM is on all the time.)
I am confused as to how you reach this conclusion? The rules clearly state that the ECM operator may stop missiles. I suppose you could argue that missiles fired from close enough to hit "immediately" are not able to be stopped by ECM because ECM is an action, not a Reaction. If that's what you mean, I agree that a sensor op should be able to hold their action to use against a missile launch. I don't agree that if they do some other ECM operation during the action phase they can also still block missiles.
 
I am confused as to how you reach this conclusion? The rules clearly state that the ECM operator may stop missiles. I suppose you could argue that missiles fired from close enough to hit "immediately" are not able to be stopped by ECM because ECM is an action, not a Reaction. If that's what you mean, I agree that a sensor op should be able to hold their action to use against a missile launch. I don't agree that if they do some other ECM operation during the action phase they can also still block missiles.
It doesn't help that I'm not actually referring to Mongoose rules. I'm adapting generic rules to what I know as a Fire Control Operator and ECM Tech in RL. I was a Naval Gunner, using systems that could do things like change frequency on the fly, change transmission to passive, if attempting to deal with active homing missiles, etc... And as an Avionics Technician on aircraft with ECM systems that for the most part were automatic (Pilot chose On/Off and the system did what needed doing). So, not really familiar with how Mongoose does Space Combat, sorry.

I'll be going through a mock combat with a GM sometime in the near future, so I expect things to 'blow up' somewhat when I see the rules in operation.

Addition: Just read through the rules. My bad. Still. No TL mod is included in the rules of the Core book. And there isn't a lot on ECM being used to deceive targeting in the initial attacks. There is the Sensor Lock and Electronic Warfare Actions. As I read these, nothing in them covers DRFM, and putting out a "False Target" that is being shot at, instead of the actual ship. The rules just don't get into the weeds.

If a ship has a good Sensor Op, and any TL advantage over the attacker/missiles, I'd add that into a few things. Harder to lock on at distance. Harder to keep a lock, and easier for the targeted ship to break the lock. And even if the missiles are at Medium and below, there is a chance some of them (or all) will miss, because of jamming at close range. As a minimum, I'd suggest that the TL difference is added into any Effect result in the combat. Now, my GM and I will have to test this out.
 
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You can do that with literally every single mechanic in the game. Take someone with real world expertise in that specific thing and they'll have a thousand things the mechanics don't cover. The movement in space is extremely abstract (even if you use the optional vector movement system). The targeting systems, ranges, and weapon specs are very simplistic. Medicine is super simplified. You name it.

There are pages of discussion on this forum about shipping by those of us who have expertise in logistics. That's fun, but I don't expect the game to actually get into that level of specialist simulation. It is irrelevant to 90% of the players, if not more.

Because it is an RPG about people doing stuff in science fiction. It is not a wargame or a simulation. You can houserule in your areas of expertise if that makes the game more fun for you and your friends at the table. My university coursework was in cultural anthropology. That gives me a wealth of ideas for making worlds more interesting, so that gets in game. My real life work is heavily involved in shipping and port operations (though I'm not directly in that field), but that would bore my players to death so that doesn't directly appear in the game (does influence some descriptions and other color I include).

My player with sensors skill is fine with "Jam comms", "decoy missiles", and "make/break targeting locks". If I tried to make it more detailed, she would just get annoyed. You may have different players :)
 
There is a whole supplement waiting to be written about sensor systems and electronic warfare across the TLs...
 
As you know, there's swarms of details in FFS (though not sure how well any of that converted to actual play, as I didn't switch from CT to those editions) and even 2300 has more detailed sensor mechanics than core Traveller.
 
The sensor rules in T4 were better, I think they had some pretty expert people working on those.
The factors to consider
Antenna area
power (active only)
radiated signature
reflected signature
electronic warfare
countermeasures
sweep volume over time
what have I missed?
 
The sensor rules in T4 were better, I think they had some pretty expert people working on those.
The factors to consider
Antenna area
power (active only)
radiated signature
reflected signature
electronic warfare
countermeasures
sweep volume over time
what have I missed?
Waaay too deep! I don't think we need that level of ganularity. One thing I'm not clear on is how vaccum will affect propagation of energy. In the atmosphere there are a lot of factors to consider, but I would think most would not apply in space. But, as mentioned above, many players won't want to wrap their brains around it. Give them something simple, but something.
I was thinking of, at least, some level of simulation and current level of technology. IIRC, the sensor lock/break thing sounds a bit like X-Wing. It doesn't cover what ECM does. And there aren't any mechanics on deployable countermeasures (flares, mini-jammers, drones and Wild Weasel missiles are not covered).

There are lots of things that current Mongoose rules don't cover without getting into formulae.
 
Waaay too deep! I don't think we need that level of ganularity. One thing I'm not clear on is how vaccum will affect propagation of energy. In the atmosphere there are a lot of factors to consider, but I would think most would not apply in space. But, as mentioned above, many players won't want to wrap their brains around it. Give them something simple, but something.
I was thinking of, at least, some level of simulation and current level of technology. IIRC, the sensor lock/break thing sounds a bit like X-Wing. It doesn't cover what ECM does. And there aren't any mechanics on deployable countermeasures (flares, mini-jammers, drones and Wild Weasel missiles are not covered).

There are lots of things that current Mongoose rules don't cover without getting into formulae.
In My mind to keep it simple in combat, sensors add a bonus to your attack roles, ECM subtracts from those same attack roles. Simple easy and "on" 100% of the time during combat. Requires no charts and no fancy knowledge. A simple sensors +, ECM -. Easy.
 
There may be some misunderstanding - antenna, TL, power input determine sensor rating

All you see on the ship sheet is A12 P6 active sensor range 16 range bands, passive sensor range 6 range bands.
ECM rating or jammer rating E6 - reduces enemy active sensor by 6

Radiated signature, passive signature - determined from a ships power rating
Reflected signature - hull size, configuration

Again all you see on the ship sheet are RaSig 6, RefSig 4.

The sensor design system which would take into account TL, antenna size, energy input etc would be there for the gearheads who like playing with that stuff.
 
There may be some misunderstanding - antenna, TL, power input determine sensor rating

All you see on the ship sheet is A12 P6 active sensor range 16 range bands, passive sensor range 6 range bands.
ECM rating or jammer rating E6 - reduces enemy active sensor by 6

Radiated signature, passive signature - determined from a ships power rating
Reflected signature - hull size, configuration

Again all you see on the ship sheet are RaSig 6, RefSig 4.

The sensor design system which would take into account TL, antenna size, energy input etc would be there for the gearheads who like playing with that stuff.
Kind of like in the GURPs Far Trader book, you have the simple trade rules for ease of play, and you have the detailed trade rules which are even too complex for Me. lol. That might now be a bad plan and it would be a way to please both styles of play.
 
For civilian ships, this all works well.

For ships with the Countermeasures Suite, there does need to be a bit more. I'm thinking along the lines of MasterGwydion's post above. However, it will depend on how the game mechanics work. Any distance to target allows for deception measures. Some will be sensors/jammers on ships.

There is nothing on decoys/deployable stuff. Sand is a version of a deployable countermeasure that works (for me) against beams in space, and there should be something for sensors and detector systems. Chaff is the current deployable stuff for messing up radar signatures. Nothing like this in Traveller. Active jammers are certainly not. Flares? Not. In space, and with higher Tech Levels, actually getting and keeping a target lock should be harder and harder. Civilian ships would be at a serious disadvantage against military/para-military ships.

Convoys with escorts through bad regions of space? I'd think so. Current world situation: Somalian Pirates.

Back to the OP: Right now, there is nothing in the rules to allow defence with Countermeasures as I read them. Not good, nor realistic in current tech, nor future TLs.

With good ECM: Is there a viable sensor lock on the actual ship? Or is the 'target' a deception? Nothing damages the target ship if the deception target is being shot at.

Notes: 1. If there is a Sensor Operator, with any skill, he can attempt to jam active homing guidance on missiles, with a DM on Delta TL. Missile TL vs Sensors TL (Or ECM suite TL)= ±DM
2. This is done every phase/turn, even if the missiles are fired at close range (Assuming there is a viable sensor lock on the actual ship, not the deception target). At longer ranges, regular rules apply, but with the Delta TL DM added to the effect (or minus. Ouch.).

There is more, but Deception stuff is needed, and not here, yet.

Image Attached: Atmosphere effects on frequency of transmission. Gases and moisture mess up sensors.
 

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