MGT Only: Stealthy missiles

[Brandon C]

Going back to the ineffectiveness of missiles (and torpedoes), a thought occurred to me ... allow missiles to use the stealth option available for starship hulls. This would cost MC 0.1 per 12 missiles and MCr 0.5 per 2 torpedoes. A gunner providing anti-missile fire must detect the incoming missiles (at -4 if they have stealth) before he can fire a laser or sand at them.

Comments?

 

[mike wightman]

Comments?

Well two things spring to mind.

There is no such thing as stealth in space.

The capability of 50kg missiles in Traveller is already magical rather than technologically explainable, adding stealth to them as well just snaps the old belief suspenders.

 

[Brandon C]

Thinking on the ineffectiveness of missiles (and torpedoes) in MgT, a thought occurred to me ... allow missiles to use the stealth option available for starship hulls. This would cost MC 0.1 per 12 missiles and MCr 0.5 per 2 torpedoes. A gunner providing anti-missile fire must detect the incoming missiles (at -4 if they have stealth) before he can fire a laser or sand at them.

The gunner does not have to make the detection roll; this can be done on the bridge an the information passed on to the gunners.

This should make it somewhat harder to intercept missiles.

Comments?

 

[Brandon C]

Worth a thread on its own...

Done

 

[Brandon C]

There is no such thing as stealth in space.

The stealth option specifically makes the surface absorb radar and lidar, as well as suppressing heat emissions. GT had similar options.

The capability of 50kg missiles in Traveller is already magical rather than technologically explainable, adding stealth to them as well just snaps the old belief suspenders.

I think MgT missiles are bigger than that and torpedoes are definitely larger.

 

[CliffBates]

If your using optic scanning yes, but radar, microwave and laser based radars/sensor systems bounce back.. now what happens if your ships or missiles have on them absorbent or refracting but in alternative coating. What happens is radar would not get the single back.

Now energy sensors would can detect energy but since there is all this energy in the background, such sensors would be like sonar sound sensors trying to find what is a ships motion version organics. Thus the star's light waves and things that interfere with them will be a means to detect a ship.. and the like.

But this a two way street... hence again, optics are the best.. and with lenses crafting the merge of digital and optic that the higher tech levels.. then the only issue is the question of how fast light travels from the source and the receiver.

 

[McPerth]

[m;]Posts copied from naother thread where this discussion started to unify it[/m;]

 

[McPerth]

Maybe all missiles should be detected before being allowed to fire against them, or maybe (to keep things simple) the sensors DM should be applied to anti-missile fire.

If stelathy missiles are allowed, then they should modify this same semsors DM.

There is no such thing as stealth in space.

We know there's no stealth in space, but another thing is if they could be detected, targeted and locked on quickly enough to be effectively fired upon

 

[CliffBates]

Lasers and counter missiles.. yes If you don't detect them you can't intersect them. So perhaps there needs to be a sensor determination roll before those can be used.

But sandcasters.... they are kinda like flack you just shoot and shoot.. and missiles and fighters run into into and bang.. (Think of the Battlestar Galactica remake and how flack operated... and this is how I think sandcasters actually operate.) And perhaps repulsers.. but that is different.. they are proximity activated so the missile or fighter is so close it can't be missed or not-detected.

Also Nuke Dampers.. they are up and up... as with other screens.

 

[Brandon C]

But sandcasters.... they are kinda like flack you just shoot and shoot.. and missiles and fighters run into into and bang.. (Think of the Battlestar Galactica remake and how flack operated... and this is how I think sandcasters actually operate.) And perhaps repulsers.. but that is different.. they are proximity activated so the missile or fighter is so close it can't be missed or not-detected.

In MgT, a Gunner must make a roll to successfully deploy sand or screens.

 

[CliffBates]

In MgT, a Gunner must make a roll to successfully deploy sand or screens.

When a unit enters a danger zone.. the screens ought to be up and running.. (meson and Nuc Dampers).. as for sandcasters/flack and repulsers they go up once missiles and fighters are in the you can't but see them. Hence this is why there needs must have numerous optical sensors on the ship's surface or on the turrets and batteries..

As for the roll... yes hitting the activate switch and or the sandcaster actually hitting the trigger.

 

[McPerth]

When a unit enters a danger zone.. the screens ought to be up and running.. (meson and Nuc Dampers).. as for sandcasters/flack and repulsers they go up once missiles and fighters are in the you can't but see them. Hence this is why there needs must have numerous optical sensors on the ship's surface or on the turrets and batteries..

As for the roll... yes hitting the activate switch and or the sandcaster actually hitting the trigger.

I agree about sand (being a "chaff" cloud) and meson screens (being screens that affect all the ship), they are just protected areas, so no gunner roll would be so needed.

But nuclear dampers are described (at least in CT/MT, I infer also in MgT) as having several nodes and antinodes, and only on them the effect of strengthening or debilitating the nuclear forces is achieved.

So, to reduce the effect of a nuke, you must focus the node/antinodes in a way that they affect it, and so, I see logical to make tho gunner roll for its use.

 

[whulorigan]

The stealth option specifically makes the surface absorb radar and lidar, as well as suppressing heat emissions. GT had similar options.

The issue really depends on how hard-science you want to be. If you are willing to introduce a significant amount of handwavium or some exotic process by which the ambient emissions of targets can be hidden against the backdrop of space (perhaps using some "otherspace", for example), then you are good to go.

But if you want something that at least gives the nod to actual science and engineering issues (even accounting for several TLs of advancement), then the problem is that space is big, vastly empty, and cold, and there is nothing to hide either behind or in the midst of.


Quoting myself from some other threads:

The problem would not be the fact that the "Ultra-Black" does not reflect any light-wavelengths; the problem would be that your hull will be radiating heat at roughly room-temperature or higher (due to the internal environment and equipment waste-heat), which means that it is literally "glowing" in infra-red against an ultra-cold 2.7 K microwave background. On Earth we can talk about masking and stealth because the temperature of the background environment and the temperature of the object in question are roughly similar, and therefore the object might not necessarily "stand-out" against the background if done properly.

The situation for a spacecraft in deep space would be analogous to a perfectly "black" piece of metal on Earth being heated to several thousand degrees and glowing red-orange due to the heat-radiation. It would be like a lightbulb in an otherwise dark room.

The thing to always keep in mind is the distinction between Active-Sensors and Passive-Sensors:

1) Active-Sensors are emitting their own signal and are typically looking for a "reflection" from the target object. Absorbent (or "non-reflective") coatings . . . are very useful in this regard, as they do not return a signal to the active-sensor. Radar is a good modern-day example. A radio-wave absorbent material (or one that causes radio-waves to be deflected at odd-angles) renders the target object hard to detect by radar.

2) Passive-Sensors are looking for emissions generated by the target object. The human eyeball is a fine example of a passive sensor that detects EM-radiation in the 380nm -760nm wavelength range. A passive sensor might detect a signal reflected off of the target originating from some other source, or might detect a signal natively generated by the target itself. A target generating an excessive signal above background might be perceived as a "bright" or "hot-spot", or a target generating below background might be picked out as a "dark" or "cold-spot".

The problem primarily arises with the issue of Passive Sensors, as noted above, because the background of space is suffused with EM-radiation at a temperature of 2.7K (in the microwave band). The habitat of a ship (even one with its power plant shut down) is radiating at ~ 300K (in the infra-red). Even though there may be many emissions of all kinds of temperatures from distant stars and other sources, a passive targeting/detection sensor will also include the ability (by triangulation) to resolve the ranges of nearby signal sources. Picking up a random 300K EM-signal is one thing; picking one up that can be resolved to lie at a range of 100,000km clearly tells you that there is an object glowing in Infrared located at that position.

Now a missile or torpedo would not necessarily have to be at room temperature (and could theoretically be cooled to 2.7K), but its propulsion and/or power system would dump out significant amounts of heat that will radiate (or otherwise need to be re-radiated somewhere else). So to "suppress" heat emissions, you need to move the heat from the torpedo to "somewhere else" (which then will show up as different heat source).

The problem is that there is no surrounding "medium" to blend into, nor are there objects to hide behind. You are a glowing infrared-hot "lightbulb" in a vast 2.7K dark room. And the only way to make your glow go away is to transfer it to something else (which will then itself be glowing-hot).


(BTW, I am all for stealth in space if one can come up with a semi-plausible, semi-scientific disbelief-suspending mechanism to do so . You're just going to need some handwavium to do it).

 

[CliffBates]

The issue really depends on how hard-science you want to be. If you are willing to introduce a significant amount of handwavium or some exotic process by which the ambient emissions of targets can be hidden against the backdrop of space (perhaps using some "otherspace", for example), then you are good to go.

But if you want something that at least gives the nod to actual science and engineering issues (even accounting for several TLs of advancement), then the problem is that space is big, vastly empty, and cold, and there is nothing to hide either behind or in the midst of.


Quoting myself from some other threads:





The problem primarily arises with the issue of Passive Sensors, as noted above, because the background of space is suffused with EM-radiation at a temperature of 2.7K (in the microwave band). The habitat of a ship (even one with its power plant shut down) is radiating at ~ 300K (in the infra-red). Even though there may be many emissions of all kinds of temperatures from distant stars and other sources, a passive targeting/detection sensor will also include the ability (by triangulation) to resolve the ranges of nearby signal sources. Picking up a random 300K EM-signal is one thing; picking one up that can be resolved to lie at a range of 100,000km clearly tells you that there is an object glowing in Infrared located at that position.

Now a missile or torpedo would not necessarily have to be at room temperature (and could theoretically be cooled to 2.7K), but its propulsion and/or power system would dump out significant amounts of heat that will radiate (or otherwise need to be re-radiated somewhere else). So to "suppress" heat emissions, you need to move the heat from the torpedo to "somewhere else" (which then will show up as different heat source).

The problem is that there is no surrounding "medium" to blend into, nor are there objects to hide behind. You are a glowing infrared-hot "lightbulb" in a vast 2.7K dark room. And the only way to make your glow go away is to transfer it to something else (which will then itself be glowing-hot).


(BTW, I am all for stealth in space if one can come up with semi-plausible, semi-scientific disbelief-suspending mechanism to do so . You're just going to need some handwavium to do it).

I agree with most of what you are saying here. But the issue is sorting out all the bits of information you are getting. As for heat signatures and energy signatures there is lots of things out there emitting them.. and they they go on and on. The bit of data you might be getting might not be data your senor bounce but a bounce from another ship's radar/sensor from a ship far far far away and it is not traveled and hitting your sensor receiver.

Also I have a question about gravtics powered.. does it generate the same heat that a rocket or HEPLaR or would? I really don't think so. Yes, there will be energy generation.. but along as its contained in the ship's field and not vented into space how would other detect it? Ok yes fusion plants might be detectable.. this is why one ought to have batteries reserves so in combat your reactor's/powerplant's reaction would not be telling the enemy where you are.

 

[whulorigan]

Also I have a question about gravtics powered.. does it generate the same heat that a rocket or HEPLaR or would? I really don't think so.

I don't believe there is canon on the issue of the heat generated by a gravitic M-Drive, so it is GM's call. But I would agree that it is probably significantly less than an operating HEPlaR Rocket.

Yes, there will be energy generation.. but along as its contained in the ship's field and not vented into space how would other detect it?

There is nothing specifically mentioned for the MgT ruleset, but according to (some) canon sources an operating gravitic M-Drive produces a brilliant blue-white glow on the exterior thruster-plates.

Ok yes fusion plants might be detectable.. this is why one ought to have batteries reserves so in combat your reactor's/powerplant's reaction would not be telling the enemy where you are.

But even if you are running on batteries, and your P-Plant is cold, you are still going to be emitting 300 K from your shipboard habitat/environment against the 2.7 K background.

Just as an aside, keep in mind that even with modern 21st century technology, the emissions from a Fusion Rocket operating in the Alpha Centauri star-system would be easily detectable from Earth-orbit (though the information would be 4.3 years out of date, of course).

 

[atpollard]

[rant deleted]

We tend to selectively apply 'reality' to suit taste.
MgT HAS rules for stealth spacecraft, so applying the technology to missiles does not seem unreasonable.

Spoiler:

I am unimpressed by claims of real world thermodynamics applied to detection of fantasy spacecraft.
First stuff the MD through the Rocket Equation and then we can talk about thermodynamics and sensors.

 

[mike wightman]

And that is why it is pointless having these discussions.

Do you want a sci fi game based on science or magic?

The laws of thermodynamics are well understood, and any future maneuver drive will still have to abide by them, unless you invoke magic.

MgT makes up a lot of magic, and quite a lot of it has no place in the OTU or in a reasonably hard sci fi setting.

Stealth in space does not exist in the OTU, and can not exist in the universe. If you want to include it you are moving well away from OTU tropes and well into the realm of science fantasy.

 

[mike wightman]

The stealth option specifically makes the surface absorb radar and lidar, as well as suppressing heat emissions. GT had similar options.

But you have no way of hiding your passive thermal signature.

 

[mike wightman]

We know there's no stealth in space, but another thing is if they could be detected, targeted and locked on quickly enough to be effectively fired upon

In CT weapons have ranges measured in light seconds.

Unless the missile is fired from close range and has massive acceleration then your weapon systems have whole minutes to acquire them, lock on and fire on them

 

[Brandon C]

But you have no way of hiding your passive thermal signature.

It doesn't make an object invisible, it just gives a -4 to spot it.