Tactical comunications is space combat

[McPerth]

When I read this post in another thread...

So, let me get this correct. Your sensors report a target at a range of 500,000 kilometers from you, or 1.67 light seconds. You now know where the target was 1.67 seconds ago. Presumably, the target is moving at a reasonably high speed, on the order of many kilometers per second. You then align your ship so precisely that you can hit a moving target of say Azhanti High Lightning dimensions, 405m long by 61.2m wide by 36.4m high, at a distance of 500,000 kilometers with a meson particle beam with the meson particles timed to decay inside of the target hull. According to T5.0.9, page 367, meson particles travel at "near light-speed". I will assume light speed to simplify things. Your particles have to be timed to decay with an accuracy of at least one-ten millionth of a second in order to order to decay within a variance of 30 meters. The beam arrives at the target range 3.34 seconds AFTER your last firing position data. In the mean time, your target has traveled for 3.34 seconds at a velocity of maybe 50 kilometers per second. You know precisely where your target is going to be after it has travelled 167 kilometers from your last position data, and you know to within 50 of so meters precisely what the range to the target is going to be, at a distance of 500,000 kilometers.

Note, your target can alter course in three dimensions, including decelerating. If it changes course by one degree, at the end of 3.34 seconds, it will have changed the straight line projects course by a matter of 2.91 kilometers.

I invite all who read this to think long and hard about the likelihood of hitting the target with your meson beam.

..I wondered about the effect this will have in thight beam communications.

While weapons may have an affected zone, or can have enough with an instantaneous hit on enemy ship (or in a blast zone engulfing it), I guess those thight beams need more sustained contact and not in a near zone, probably not even in any part of the ship, but in the receivers (taht can be quite smaller than the whole ship).

Add to this the efects of sand in laser communications (even X-ray lasers, as sand is specifically designed to stop it), Meson Screens in meson communicators, etc, and I have serious doubts about their usefulness in combat situations (I guess in non combat ones ships make an effort to be easy to lock on by friendly communications).

So, my guess is that the most used communications in tactical (combat) situations among ships keeps being the old fashioned but broadcasting radio, even while being the easiest to detect by the enemy, whith al lthe consequences that may have.

And any ship using a Black Globe will not have reliable communications even by radio, as all incoming energy (incluiding EM radiations) are absorbed by it, and only the off moments when flicking will be able to receive, so receiving them quite partially...

 

[Supplement Four]

Given Traveller tech, it's very unlikely that the ship can alter its vector by even one degree in that short a time. The example timerover51 gave stipulated the target vessel moving at a high speed. This means it will be pretty easy to predict where the ship will be seconds in the future. Therefore, targeting isn't a problem.

For example, THIS AZHANTI has a 2G maneuver drive. Let's say that it has just entered the system 10 diams out from a Size 8 world (and let's assume that it entered the system at relative velocity of zero, to make it easy) and it traveling to make orbit.

This trip will take 264 minutes.

And, when you target the ship, it is 120 minutes into this trip. The Azhanti, with constant acceleration (hasn't reached midpoint yet) is traveling at an incredible speed, pulling a lot of Gs.

That 2G M-Drive is going to take a long, long time to build up enough force to alter the ship's path.

That's the simple thing about Traveller technology and game mechanics. Unless the ship is moving at a very low speed, maneuverability is zilch. The ship, for all practical purposes, is moving in a straight line.





BTW, this also goes for the attacking vessel. If you are 500,000 km out from the target (and let's say the Azhantic target is moving perpendicular to your course), you are only going to have X number of opportunities to fire your weapon at the target as it will soon be out of range.




One of the cool things about CT Book 2 combat, with the protractor, ruler, and the kitchen floor, is that it brings this aspect of Traveller space combat into focus.

 

[Orr]

...I wondered about the effect this will have in thight beam communications.

As others in this and the other thread have explained, timerover's "concerns" are typically overblown.

Getting back to comms, I think you're too fixated on the "tight" in tight beam. A laser/maser beam is going to be pretty spread out by the time it travels a few light seconds. (Remember, TNE had to introduce gravity focusing so it's somewhat more realistic laser weapons could do damage at ranges which were still shorter than the laser ranges in previous versions Traveller.)

Depending on the technology involved, that "tight" beam is going to have a surprisingly wide footprint at it's destination. The sender isn't going to have to "aim" at a small antenna on the receiver's hull because their signal is going to be spread out in a disc wider than receiver's hull.

Tight beam comms are only "tight" in comparison to radio

Looping back to the aiming thread which spawned this one, we need to remember that lasers, energy weapons, and spinals in ship combat are not firing single shots each round. Rather, multiple shots are being made during the round which are treated as single shots for play purposes. Either CT, MT, or both mentions this in their color text and both CT and TNE allow combat bonuses when weapons are powered to fire more volleys than normal.

Attempting to hit an opponent with a laser in Traveller isn't the matter of taking one shot at one position where the opponent is predicted to be. Instead, you're take several shots at several predicted positions while treating them as a single shot for simplicity.

 

[kilemall]

This issue will show up in my IMTU article megaarticle, but in general, I am working from an entirely different set of assumptions.

Most EVERYTHING hits at that close a range, the question is do you penetrate the hull and do meaningful damage, and that evasion is mostly about the hull moving too fast in unpredicted ways to allow enough joules to hit the same spot to do that damage.

What counts is total hull facing at the time of the shot, and how much you can move in that 1.67 seconds from a roll, attitude thrusters to one side or another, and/or a variable thrust from the main maneuver drive, while the firing ship is trying to keep that weapon focused on that specific moving point on the target hull.

A spinal mount shot would last several seconds and run through an arc of movement, so unless it's a small craft on 6Gs, ya it's likely going to hit.

 

[Orr]

...mostly about the hull moving too fast in unpredicted ways to allow enough joules to hit the same spot to do that damage.

No. All the energy in a laser, energy weapon, or spinal mount hit arrives within a miniscule fraction of a second. Those weapons project huge energies which hit in what is basically an instantaneous amount of time.

You don't need to hold the beam on target to "melt" through the hull as if the that 57th Century megajoule laser turret is just some 1970s 120vac CO2 laser straight out of a high school science lab.

What counts is total hull facing at the time of the shot...

That's straight out of TNE.

... and how much you can move in that 1.67 seconds...

All the energy contained in that laser, energy weapon, or spinal hit is going to arrive within an extremely small fraction of a second so it doesn't matter how much the ship can moved in 1.67 seconds when all the energy arrived in 0.0000001 seconds.

... from a roll, attitude thrusters to one side or another, and/or a variable thrust from the main maneuver drive...

That's the agility concept from HG2. Agility prevents hits, however. It doesn't limit damage.

... while the firing ship is trying to keep that weapon focused on that specific moving point on the target hull.

No need to focus when all the energy basically arrives instantaneously. It's not 50 megajoules arriving spread out over 2 seconds, it's 50 megajoules arriving in an instant.

A spinal mount shot would last several seconds and run through an arc of movement, so unless it's a small craft on 6Gs, ya it's likely going to hit.

Or a spinal mount would work as described in canon and make several instantaneous shots aimed at different points which are treated like a single shot for simplicity.

 

[kilemall]

Shrug. I'm not really dealing with canon over X number of Traveller iterations. If you say and can prove that's what the current versions say, fine. I'm still playing with the CT/HG stuff and not terribly concerned by canon.

So if that's your cup of tea, enjoy, I don't have to bow to any specific set of rules other then acknowledge their existence and play by them if I were playing in X campaign.

I am well aware of the general concept of multiple shots in a buckshot pattern, having been a naval mini person years before being a Traveller one. I have it incorporated as an option into my upcoming IMTU posting regarding battery fire in a CT combat resolution.

If you are talking about sequential shots, then frankly they should have the option of doing a heckuva lot more damage given the relative slowness of our craft to throw off potential target aimpoints.

However, I will throw this out there- if lasers deliver their hits in a fraction of a second, why is there a difference between beam lasers having a higher to hit, and pulse lasers delivering more damage but having less chance to hit?

My answer is that it is because the beam laser is firing longer in a continuous shot allowing for a better chance to hit, at the expense of high amounts of energy per fractional shot.

Oh, while we are at it, might as well go over how I explain the 100 ton per turret thing.

It's because the lasers are actually built into the hull and several dozen meters long, the turret is just the directing lens plus access point for missile loads from inside the ship out of the fire control tonnage (plus gunner workstation), so there is no room to be placing more lasers with the requisite length.

 

[Orr]

Shrug.

Sorry. I missed the IMTU tags in your posts. It's your TU, do whatever you see fit.

 

[aramis]

All the energy contained in that laser, energy weapon, or spinal hit is going to arrive within an extremely small fraction of a second so it doesn't matter how much the ship can moved in 1.67 seconds when all the energy arrived in 0.0000001 seconds.

Actually, what matters is if it can move more than it's own smallest dimension in twice the distance in LS plus the time to make the fire decision and point the weapon. That's the only way that there should be a chance of miss given modern radar accuracies (≤0°0'10" accuracy with a 1m weapon-mounted dish; more accuracy {lower angle} given synthetic aperture multiple dishes and larger dishes) and laser accuracy (±10m at 1.5 LS - apollo lunar reflector targeting)... Note that the DSN scopes have 0° 0' 0.1" pointing accuracy...

Not cheap, but well within the capabilities of TL8. Now, think about TL 12+...

 

[Timerover51]

When I read this post in another thread...
..I wondered about the effect this will have in thight beam communications.

While weapons may have an affected zone, or can have enough with an instantaneous hit on enemy ship (or in a blast zone engulfing it), I guess those thight beams need more sustained contact and not in a near zone, probably not even in any part of the ship, but in the receivers (taht can be quite smaller than the whole ship).

Add to this the efects of sand in laser communications (even X-ray lasers, as sand is specifically designed to stop it), Meson Screens in meson communicators, etc, and I have serious doubts about their usefulness in combat situations (I guess in non combat ones ships make an effort to be easy to lock on by friendly communications).

So, my guess is that the most used communications in tactical (combat) situations among ships keeps being the old fashioned but broadcasting radio, even while being the easiest to detect by the enemy, whith al lthe consequences that may have.

And any ship using a Black Globe will not have reliable communications even by radio, as all incoming energy (incluiding EM radiations) are absorbed by it, and only the off moments when flicking will be able to receive, so receiving them quite partially...

I would say that you are correct in your assumptions, which is why I have a very low regard for any form of space combat, which does not exist in My Traveller Universe.

 

[Orr]

Actually, what matters...

I was responding to Kilemall's concerns about aiming and/or focusing a laser beam on a specific part of the hull for an appreciable amount of time to do any damage.

He'd posted about how "... evasion is mostly about the hull moving too fast in unpredicted ways to allow enough joules to hit the same spot to do that damage." I replied that OTU weapons deliver their energy within tiny fractions of a second. While it may take seconds for the laser pulse/strike to reach it's target, all of the energy within that pulse/strike arrives pretty much at the same instant. So, while the movement of a target effects aiming, that movement doesn't also effect damage when the laser pulse/strike arrives because all that energy arrives in essentially the same instant.

Of course, I'd stupidly overlooked the fact that Kilemall was talking about his own TU. Lasers in his TU work differently so holding an aiming point for an appreciable amount of time is necessary.

 

[kilemall]

I was responding to Kilemall's concerns about aiming and/or focusing a laser beam on a specific part of the hull for an appreciable amount of time to do any damage.

He'd posted about how "... evasion is mostly about the hull moving too fast in unpredicted ways to allow enough joules to hit the same spot to do that damage." I replied that OTU weapons deliver their energy within tiny fractions of a second. While it may take seconds for the laser pulse/strike to reach it's target, all of the energy within that pulse/strike arrives pretty much at the same instant. So, while the movement of a target effects aiming, that movement doesn't also effect damage when the laser pulse/strike arrives because all that energy arrives in essentially the same instant.

Of course, I'd stupidly overlooked the fact that Kilemall was talking about his own TU. Lasers in his TU work differently so holding an aiming point for an appreciable amount of time is necessary.

I don't mind a discussion on the merits of one view on modelling weapons or another, either from a taste, an engineering challenge or probably most importantly a look and feel and dramatic effect.

I did not come to my view casually, went through a lot of material about how big a laser it takes to do CT ranged battle for instance. Worked through the Atomic Rockets site like I imagine most of us have including the Boom Table, did the joule calc off the hard number derived from 50kg of missile slamming into ships from the missile supplement, and this site specifically made an impression on me.

http://www.rocketpunk-manifesto.com/2009/08/space-warfare-v-laser-weapons.html

I am assuming gravitic lens, more efficient gain medium, precision minimirrors maximizing amplification runs, more powerful pumps, all in order to fit our ships without making them spinal weapons.

Also thought through most especially the Auto/Evade and Maneuver/Evade programs and what they were doing, and how much a ship can move in 1.76 seconds x 2 (the time for the latest incoming sensor return to hit and process vs. outgoing weapons fire).

They just don't move far enough unpredictably to generate misses, unless they are wee small craft with big engines. So it has to be something else. I choose hull burn rate, given the above sort of numbers for small ship sized lasers and the apparent toughness of our hulls given the high MJ required to achieve a hit.

I have dispersion built into loss of deliverable energy with range mods similar to the -2/-5 mods, although a bit smoother.

Also, worked out that Return Fire is a mode for the lasers to take advantage of the incoming fire as a datum point.

In other words the enemy shots themselves are effectively 'sensor returns', cutting the data return/fire cycle in half, and if you fire based on them you can reduce the total amount of energy required to yield the same damage because you have the strongest signal possible from the enemy ship, their direct fire, and thus more accurate fire requiring less 'time on target'.

The advantage of which is to allow a faster cooling off period and thus a higher ROF if left in Return Fire mode or switching to Anti Missile OR Offensive Fire mode.

But it has to be that very second which is why the shot must be automated and the laser turret put in Return Fire mode to take such a shot.

 

[mike wightman]

Some random thoughts on this.

Once you start to analyse things to this degree of detail you quickly realise that the ship combat model presented in Traveller is pants.

The gravitic focusing necessary to make laser weapons useful at light second ranges. Pure fantasy - why is extreme gravitic manipulation not used in other ways?
You could make a pretty scary mass driver weapon if you are capable of the thousands of g necessary to focus your laser. Alternatively you have to move the laser weapon to shorter and shorter wavelengths to achieve the range - x-ray and gamma ray become the only none magitech way of doing it, and even then the range will be just reaching the light second range.

Within a certain range a hit is guaranteed, so expensive ships with lots of live people onboard are going to stay away from the autokill range and fight it out with remote weapons, only closing when you have damaged your enemy to such a point you can take the risk of soaking the limited incoming fire while you deliver the killing blow. (this becomes the T2300 Star Cruiser game if you are not too careful )

The alternative to this would be to run away when your robotic weapon systems are losing, or surrender and offer a ransom for your safe repatriation (chivalric combat in space...)

Third - ships would spin around their axis to spread any laser hits over the maximum amount of hull, armour may well become plasma held in a magnetic or gravitic field designed to absorb the laser wavelengths, necessitating weapons that can disrupt the plasma to allow the laser through. Or how about a repulsor based on that magical grav focusing technology designed to unfocus the incoming laser...

 

[kilemall]

Spme random thoughts on this.

Once you start to analyse things to this degree of detail you quickly realise that the ship combat model presented in Traveller is pants.

The gravitic focusing necessary to make laser weapons useful at light second ranges. Pure fantasy - why is extreme gravitic manipulation not used in other ways?
You could make a pretty scary mass driver weapon if you are capable of the thousands of g necessary to focus your laser. Alternatively you have to move the laser weapon to shorter and shorter wavelengths to achieve the range - x-ray and gamma ray become the only none magitech way of doing it, and even then the range will be just reaching the light second range.

Within a certain range a hit is guaranteed, so expensive ships with lots of live people onboard are going to stay away from the autokill range and fight it out with remote weapons, only closing when you have damaged your enemy to such a point you can take the risk of soaking the limited incoming fire while you deliver the killing blow. (this becomes the T2300 Star Cruiser game if you are not too careful )

The alternative to this would be to run away when your robotic weapon systems are losing, or surrender and offer a ransom for your safe repatriation (chivalric combat in space...)

Third - ships would spin around their axis to spread any laser hits over the maximum amount of hull, armour may well become plasma held in a magnetic or gravitic field designed to absorb the laser wavelengths, necessitating weapons that can disrupt the plasma to allow the laser through. Or how about a repulsor based on that magical grav focusing technology designed to unfocus the incoming laser...

Well, thought about the plasma shield of course, decided to keep the 'Traveller feel' and argue that it just takes too much juice to cover the whole hull in the stuff all the time, that jump with the jump bubble is actually an outlier showing just how much more power and fuel it takes to put up a full shield.

The repulsor is pretty easy, if it takes 100 ton bays to swat aside 50 incoming missiles which I would think would be a lot easier to push around then a laser (being physical objects with a small gravitic field to push against), again very difficult to spend the energy to protect the whole hull, you would have to have repulsors on tap to mess with the incoming beam after the first second, and just like a missile strike you would be seeking to overwhelm the repulsor's ability to focus on X beams at a time.

As for mass drivers, already in, I'm just using PA stats and costs, difference is the mass drivers 2 surface hits instead of 1 surface and 1 rad (if using HG straight up).

2300 was my last Traveller version prior to dropping the hobby. Don't mind the SC combat mindset, a lot of logic to it, but my friends never got into it so we are going old school. Likely though for any serious combatants beyond adhoc equipped pirates and their player prey, armor will be a BIG DEAL and allow for closing.

Finally, on the Sand issue, sand is where its better to actually plot out the movements rather then use these band things. If you maneuver you should be able to eventually flank an opponent (especially outnumbered) and get him on a non-covered vector, or at least force him to deploy sand in every direction.

Alternatively, since sand is fired out to provide a cone of protection, it has velocity of it's own and will eventually disperse, requiring constant replenishment and new fields laid down, also when the target ship moves past, at angles to or through it's own protective sand screen.

 

[whartung]

Once you start to analyse things to this degree of detail you quickly realise that the ship combat model presented in Traveller is pants.

Actually, you find space combat in general is "pants".

Space combat is two guys with computerized gun mounts in a bull ring. Going to be very lethal.

Combat will take places on the fringes of accuracy and capability. Go within the envelope, and you'll die. On the edges, chance will have some say.

But it's not a game of maneuver, it's simply a game of attrition and numbers. Ranks of soldiers standing in front of each other hoping their brass buttons will protect them. When the parties engage, the outcome is mostly decided, all that needs to be determined is the cost.

High Guard models this quite well.

 

[mike wightman]

Actually, you find space combat in general is "pants".

Yup

Space combat is two guys with computerized gun mounts in a bull ring. Going to be very lethal.

And another yup.

Combat will take places on the fringes of accuracy and capability. Go within the envelope, and you'll die. On the edges, chance will have some say.

Which is pretty much what I said - manned craft will not close until the autonomous combat vehicles have decided the winner. Loser either runs, surrenders or dies.

But it's not a game of maneuver, it's simply a game of attrition and numbers. Ranks of soldiers standing in front of each other hoping their brass buttons will protect them. When the parties engage, the outcome is mostly decided, all that needs to be determined is the cost.

Economics and logistics.

How many robot combat craft can I bring to the battle. If I have more than my opponent I can dictate terms (see above) - if less I run away.

High Guard models this quite well.

Not really, the chances to hit are far too low. Unless you assume fighting beyond the autokill range, in which case the suicide attack tactic of Imperium and Dark Nebula may well have to be adapted to HG2

 

[Orr]

Combat will take places on the fringes of accuracy and capability. Go within the envelope, and you'll die. On the edges, chance will have some say.

Which is pretty much what I said - manned craft will not close until the autonomous combat vehicles have decided the winner. Loser either runs, surrenders or dies.

I think there's a sensor/ECM/ECCM struggle going on that the various ship combat systems barely hint at but - yup - I pretty much agree with you two.

 

[Condottiere]

Or you swarm, and flood the ether with electronic noise.

 

[kilemall]

Too many wavelengths for everything to be jammed-

Visual/Occlusion
Neutrino
Mass
IR from Reactor, Ship environment
LIDAR
RADAR
Electric/electronic emissions

And I am sure plenty of other EM I am not considering.

There are those Neural Activity Sensors, for those so inclined.

I would think the best ECM is no detection, using the volume of space itself to split the tender attentions of the sensor crew. Once detected, they are likely to retain eyes on, the only question being what degree of accuracy the target solution has right before firing.

 

[wbyrd]

Too many wavelengths for everything to be jammed-

Visual/Occlusion
Neutrino
Mass
IR from Reactor, Ship environment
LIDAR
RADAR
Electric/electronic emissions

And I am sure plenty of other EM I am not considering.

There are those Neural Activity Sensors, for those so inclined.

I would think the best ECM is no detection, using the volume of space itself to split the tender attentions of the sensor crew. Once detected, they are likely to retain eyes on, the only question being what degree of accuracy the target solution has right before firing.

ECM, And ECCM are highly dynamic specialties in warfare. Even at our low tech The major powers are constantly inventing, and countering detection systems. In most cases it's not about turning an object invisible to radar, or other sensors, it's about limiting the useful information that can be obtained by them.

In some cases all you have o do is generate a stronger signal nearby and your own singature is hidden by the "glare" of the decoy..like firing a flare to spoof a heat seaker...In other cases its convincing a radar system your a false return..such as flying very close to the ground nd at a slow speed so that you get confused with ground clutter....Not the best example for spatial combat but you get the idea I hope...

 

[kilemall]

ECM, And ECCM are highly dynamic specialties in warfare. Even at our low tech The major powers are constantly inventing, and countering detection systems. In most cases it's not about turning an object invisible to radar, or other sensors, it's about limiting the useful information that can be obtained by them.

In some cases all you have o do is generate a stronger signal nearby and your own singature is hidden by the "glare" of the decoy..like firing a flare to spoof a heat seaker...In other cases its convincing a radar system your a false return..such as flying very close to the ground nd at a slow speed so that you get confused with ground clutter....Not the best example for spatial combat but you get the idea I hope...

I'm an old school gamer, most notably naval minis, so yes I am clear on that, but I am also clear that most modern naval sensor tech is working visual, RADAR or IR, nice combined things like CHAFFROC can mess with multiple spectra at a time but the Traveller sensor suite is loaded with a tough combo of things to fool, all at the same time.

One could probably work several decoy/flares into the sandcaster model, but each should be good at it's intended target, or if mixed be less effective then a 'pure' caster round aimed at specific active or passive sensors.