Pondering visual range space combat

[Carlobrand]

Visual range space combat isn't a thing in Book 2 or High Guard. It gets a hint of a treatment in MegaTraveller, but given the disparity between weapon power in ground combat and weapon power in space combat, there maybe needs to be a bit more attention paid there. Basically, other than staying away by having the same or better G-rating and a friendly starting vector, very little keeps a fighter from closing up within a few kilometers of a target. Well, there's the getting blasted out of space bit, but there always seem to be so many of the little things that this really isn't going to stop them from getting through and chewing up a target close up, not if they have sufficient numbers. And, there are points where staying away isn't really an option, such as when you're trying to keep the other guy from getting close enough to your planet to start blasting it with nukes or landing troops.

Integrating it into High Guard is easy enough - add a visual range to the long and short ranges, let them move to it from short range and from it to short, make a few rules to address a few points (like maybe adding a special Battle Formation substep so the opposing fleets have a change to throw fighters and escorts to the line to protect their heavies). It's just that the secondary weapons become quite deadly, especially the energy weapons (and the particle beams, if that bit about their penetration in MT is applied). Fighters become the predominant arm, if you have a reasonable expectation of bringing the other guy to visual combat range.

That can be averted to some extent by instead moving to a hex map, allowing fleets to maneuver to try to avoid opposing fighters. A maneuvering fleet with good drives - one that feels it might be at a disadvantage with respect to the opponent in a fighter duel - can hold the enemy out where any small craft can be carved up with Factor 9 batteries, obliging the enemy to keep small craft stowed and fight it out the old-fashioned way unless some opportunity presents itself. That does however mean a running battle, which means the fleet will be less able to defend a planet. (On the other hand, a planet is a dandy carrier, which means the attacker now faces the problem of how best to deal with those fighters so its troops and missiles can reach the surface without the ships getting chewed up in the process.)

The other way to avert it would be to reconsider the power of the energy weapons (and particle beams), ignoring canon and making a house rule that maybe makes them less powerful but more likely to hit, which makes a bit of sense since High Guard is making them more likely to hit with higher levels, instead of giving them added penetration. So, for example, the 2 EP fusion gun becomes a gatling array of several lower power guns instead of a single uber-deadly gun. (Striker had this thing setting a cap on the power of rapid-pulse energy weapons, so you'd need to do some sort of a gatling treatment to get around that. As for particle beams - that 250 times UCP factor thing sounds a bit overpowered.)

The third way is - well, both Striker and MegaTrav do this thing where speed and evasion are very effective ways for a high-g craft to avoid anything but missiles. Seems unrealistic: far future tracking systems ought to be able to hold a target in the crosshairs well enough that a laser shouldn't be bothered much by jinking. Certainly they should in space. Still, RAW, it's essentially impossible to hit a high-G evading target with anything but a missile at visual range, so one could craft modifiers that reflected the Striker or MT view of visual range space exchanges.

 

[kilemall]

Got three reactions to this.

#1 if going close scratches your itch, the Mongoose ranges are more in keeping with the 10 km to 50000 km feel, and has the benefit of faster action/round times.

#2 in thinking 'visual', I don't really limit my ship sensors to just what can fit in X lens and camera. Instead I assume a VLA approach with sensors studded all over the hull, which would include optical. May not be something practical at 3 LS, but I think 1-2 is reasonable.

#3 as for range vs. penetration, I have it using High Guard but going both ways- increasing probability of to-hit AND penetration/damage. The idea being there is less rolling/viffing to get a deflection/miss that a target can do the closer in one gets, and therefore the firing vessel can concentrate fire more, less firing at all potential locations, and less attenuation as distance closes.

The trick is to increase the weapon factor rating which increases probability, and rework the armor so that weapon factor matters more, beyond the small weapon vs. spinal break.

So little single laser hits can literally bounce off the armor- unless one closes under 100,000 km, where I have it REALLY jump up in damage.

Among other things, the Gazelle's gig makes sense for a boarding party, you don't risk the whole CE on the approach with a surprise ambush, if the gig gets fired upon the CE can still be at optimal range to deal with the miscreants.

 

[Fovean]

I play Mongoose these days; your idea about visual range sounds like Adjacent, Close and Short ranges in MgT (up to 1,250 km). Medium range jumps to 10,000 km, which feels too far for visual to me.

I give all energy weapons a DM+1 to hit and damage for each range band inside its maximum and DM-2 to hit and damage for each range band beyond that. So a Medium range beam laser looks like this:

Beam Laser Atten/Pen
Adj DM+3
Close DM+2
Short DM+1
Med DM+0
Long DM-2
VLong DM-4
etc

I've been pondering this for railguns, as well as well as the ion and tachyon weapons but it might be getting into overkill territory.

 

[Brandon C]

I've been pondering this for railguns, as well as well as the ion and tachyon weapons but it might be getting into overkill territory.

While railgun accuracy will drop off (they are basicslly missiles with vector and velocity fixed at firing), damage won't drop off.

 

[kilemall]

Oh one other visual range goodie-

Always figured the most horrifying thing would be a fighter using a VRF Gauss Gun firing Californium needle rounds.

Fighter ND protection box protecting the ammo until closing, then 1000s of rounds raining down in-between the defending ship's ND nodes.

Just one gets through, buh-bye dreadnought.

 

[LeperColony]

In TNE it's stated at the standard Imperial MBT is a match for most starships, with range being the primary limitation. Of course, "most starships" would include lightly armored commercial vessels.

 

[mike wightman]

Oh one other visual range goodie-

Always figured the most horrifying thing would be a fighter using a VRF Gauss Gun firing Californium needle rounds.

Fighter ND protection box protecting the ammo until closing, then 1000s of rounds raining down in-between the defending ship's ND nodes.

Just one gets through, buh-bye dreadnought.

Why doesn't the dreadnaught fire its own VRF Ca rounds from point defense emplacements at the fighters to take them out at longer ranges thanks to the better sensors on the dreadnaught? Or even build bigger VRF point defence systems with longer range than the smallcraft can carry?

If visual range smallcraft dogfights are something to be modelled in a homebrew universe then care must be taken to explain exactly how the 'fighters' have such a maneuver advantage over the capital ships, and how they can survive the thousands of km of space they have to cross filled with laser, point defence, anti-fighter missiles/drones etc.

 

[mike wightman]

GURPS Spaceships has some pretty good rules for changing the scale of space combat as range decreases by the way.

Smallcraft will always have the following disadvantages compared to the big ships unless you handwave technology to skew things in the smallcraft's favour:

Power - big ships have much more room for big power plants. This gives them superior sensor range, bigger/faster firing railguns, the ability to power laser weapons.

Armour - a big ship can have much thicker armour than any smallcraft.

Engines - big ships can have bigger maneuver drives and still have room for other stuff.

Endurance - the big ship can maneuver for days, weeks, months.

The smallcraft will have an advantage in agility in the sense it can spin around its own centre of gravity faster and then point its engines in a different direction faster than a big ship.

Current real world technology for point defence systems is pretty scary stuff - extrapolate it to space based and base it on railgun research and you increase the velocity of the projectiles to 5-10km/s for solid rounds or 200km/s+ for plasma rounds (yup - a real area of research). Current real world laser weapons actually work, but take up a lot more space in a ship than the emitter you see on deck...

 

[whartung]

I have a couple of problems with visual range combat.

First, it's dark. Really dark. Of course I'm talking deep space hear, not near some bright shiny solar reflector of a planet. Combine dark space with ships painted black and, well...anyway. It's dark.

Second, closing velocities. That Adams guys mentioned something about the size of space. Which means that ships need to go pretty fast to get anywhere in any reasonable amount of time. At the speeds ship travel, they will be in, and back out of visual range very, very quickly. They pretty much need to fly up to each other and park before combat ensues, but in order to do that, they need to know where each other are OUTSIDE of visual range. And if you know where the ship is, and you're outside of visual range then, well, why do you need to be in visual range?

I guess if you're hurling grapeshot at each other, it's important.

Now, to those points, pretty much all of the cinematic space battles are in visual range. But even today modern combat is of the "Hey guys, there's a red-thingy moving toward the green-thingy".

If you have to be that close, due to weapons constraints, then you have to be that close. But just seems to me someone clever will strive to not want to be in that situation where two ships agree to meet somewhere and then just blast each other to smithereenies hoping, in the end, that their smithereens are bigger than their opponents.

 

[kilemall]

Why doesn't the dreadnaught fire its own VRF Ca rounds from point defense emplacements at the fighters to take them out at longer ranges thanks to the better sensors on the dreadnaught? Or even build bigger VRF point defence systems with longer range than the smallcraft can carry?

If visual range smallcraft dogfights are something to be modelled in a homebrew universe then care must be taken to explain exactly how the 'fighters' have such a maneuver advantage over the capital ships, and how they can survive the thousands of km of space they have to cross filled with laser, point defence, anti-fighter missiles/drones etc.

Of course, and Traveller capital ships would not be helpless hapless ships against fighters as re: Star Wars.

High agility for one on the closing part, and then numbers and cheapness vs. consequences if they get through.

Say 3 BCr for 300 fighters, just 5 surviving do in 2 dreadnoughts, that's peanuts in HG costing.

Heck even the Heavy Fighter from Fighting Ships would 'just cost' 30 BCr for the same cost and have that computer capability for surviving the close approach, still a steal for investment vs. results.

Except maybe for the pilots.

 

[kilemall]

I have a couple of problems with visual range combat.

First, it's dark. Really dark. Of course I'm talking deep space hear, not near some bright shiny solar reflector of a planet. Combine dark space with ships painted black and, well...anyway. It's dark.

Occlusion, which would be bigger the closer you are.

Second, closing velocities. That Adams guys mentioned something about the size of space. Which means that ships need to go pretty fast to get anywhere in any reasonable amount of time. At the speeds ship travel, they will be in, and back out of visual range very, very quickly. They pretty much need to fly up to each other and park before combat ensues, but in order to do that, they need to know where each other are OUTSIDE of visual range. And if you know where the ship is, and you're outside of visual range then, well, why do you need to be in visual range?

I guess if you're hurling grapeshot at each other, it's important.

IMTU it's mutual suicide- maybe somebody is trying to accomplish something before they are torn to ribbons by superior numbers/tech anyway.

Not only are the energy weapons having to cover far fewer alternate endpoints for ever lesser movement times, they are attenuating less, and if you are making runs at each other the kinetic impact of missiles will also be daunting.

But otherwise, no you aren't matching vee unless one side is far more agile then the other and wants to close. It will happen primarily to board a largely immobile or surrendered ship.

Now, to those points, pretty much all of the cinematic space battles are in visual range. But even today modern combat is of the "Hey guys, there's a red-thingy moving toward the green-thingy".

If you have to be that close, due to weapons constraints, then you have to be that close. But just seems to me someone clever will strive to not want to be in that situation where two ships agree to meet somewhere and then just blast each other to smithereenies hoping, in the end, that their smithereens are bigger than their opponents.

One side will want to leave and it should be pretty easy to stay out of range, or endure only one pass and then be gone.

The one exception is planets, a defender may be forced to hold the line even though force-in-being logic would suggest leaving is highly prudent.

So, most battles in a visual range only universe would revolve around planets, where a fast pass is probably a Bad Idea.

 

[whulorigan]

I have a couple of problems with visual range combat.

First, it's dark. Really dark. Of course I'm talking deep space hear, not near some bright shiny solar reflector of a planet. Combine dark space with ships painted black and, well...anyway. It's dark.

The background may be dark, and the ship may be painted black, but the ship will be glowing brightly in the infra-red (~ 300K from its own internal heat emission, at least) against a cold, black microwave (2.7K) background. And there is nothing to hide behind.

 

[wellis]

The background may be dark, and the ship may be painted black, but the ship will be glowing brightly in the infra-red (~ 300K from its own internal heat emission, at least) against a cold, black microwave (2.7K) background. And there is nothing to hide behind.

Does Traveller, of any version, actually deal with ships having to radiate heat to cool off?

 

[whulorigan]

Does Traveller, of any version, actually deal with ships having to radiate heat to cool off?

Both TNE & T4, I believe.

 

[kilemall]

The background may be dark, and the ship may be painted black, but the ship will be glowing brightly in the infra-red (~ 300K from its own internal heat emission, at least) against a cold, black microwave (2.7K) background. And there is nothing to hide behind.

Freon sand canisters.

 

[mike wightman]

Refrigerate and insulate your hull facing the target, dump your heat out of the glow strip on the back of your ship...

Traveller (apart from TNE and T4) doesn't do thermodynamics, there has to be a magic heat sink technology that we have never been told about - IMTU it is based on gravitics just like the artificial gravity and the acceleration compensation.

In my more hard sci fi campaigns heat management and radiators are very important - but then ships don't have multi-gigawatt fusion power plants and rocket plumes can dump heat.

 

[whulorigan]

Refrigerate and insulate your hull facing the target, dump your heat out of the glow strip on the back of your ship...

Traveller (apart from TNE and T4) doesn't do thermodynamics, there has to be a magic heat sink technology that we have never been told about - IMTU it is based on gravitics just like the artificial gravity and the acceleration compensation.

My handwave is similar: since a gravitic M-Drive (in my interpretation) reacts against other gravitational masses within a star-system, it (or a related technology) likewise can dump the heat from the ship into those bodies by an equivalent amount via the gravitic interaction.

 

[mike wightman]

I hope you don't mind but I may just have to steal that idea...

 

[whulorigan]

I hope you don't mind but I may just have to steal that idea...

If you come up with any good corollaries or spin-offs, I hope you will return the favor.

 

[Carlobrand]

I'm not real familiar with Mongoose, picked it up and looked a bit at it a year ago but not enough to really grok it. Still, that's on my to-do list at some point in the future.

I'm trying to stick to the CT-MT rule structure to the extent possible, since that's what I'm most familiar with. In this context, that means drawing on either MT Player's Handbook or Striker for some of the weapon ratings, which mean "visual range" is defined more by the power of the weapons than by what people can see. That is to say, when the ranges are in the tens of thousands of kilometers the space combat rules are allowing a single laser to hit on 8+ in about a thousand seconds before other effects are considered, and at battlefield combat effective ranges - when the ranges sink to a few kilometer and the turn is measured in seconds or tens of seconds - your weapons have exactly the same odds in Striker and slightly better odds in MT Player's Handbook, 7+ (if the combatants are within 500 meters or at TL14-15, oddly worse odds if they're TL13- and at 500m - 5 km). Meanwhile, the various turret weapon penetration ratings double within 5 kilometers, so weapons that were just taking out the occasional turret at 10,000 kilometers are carving up ships like a Christmas goose at 5 kilometers.

A couple of other things change. Computers are critical in High Guard/MT space combat, less so in visual range combat (where size and evasion are more significant). Assuming the computers are at least smart enough to give you an outline of that black building-size shape occluding stars a kilometer off the port bow (assuming we've overcome the problem of glowing like a star in infrared - which by the way I love that grav-dump idea), that's to be expected: hitting a building silhouetted against the night sky is not terribly difficult given any reasonable technological aid. I'm inclined to think evasion is overrated, or maybe size underrated, given that ships are from house-size to skyscraper-size and that even at 6G you aren't going to change your position by more than a couple of meters in the reaction time of a typical person. Striker handles that better, since MT doesn't have anything but the one

There are a couple of reasons this interests me. It means lower tech ships have a chance in a fight against higher tech ships if they can get close enough to make tech less relevant - the trick of course being to persuade the superior enemy to let you get that close, but fleets trying to attack or defend planets may not have the same degree of freedom to keep opponents at spinal range as they would in open space, and most fights will be over some strategic target rather than in deep space. On the subject of planets, it changes the character of a planetary assault if a planet can mount a credible threat with fighters, since the attacking fleet can't just hang out there at long range and hope to pick out planet-based targets from the bulk of the planet.

Key to whether fighters become a dominating threat or just an effective support is the treatment of energy weapons, specifically the fusion gun. Played as written - well, imported into CT/MT visual range combat with the penetration as described in MT PH - the weapon punches through the thickest CT battleship armor and comes pretty close against the max 40+(5*TL) MT armor, enough to pretty well immobilize the behemoth in a single round given the potential number of attacks and the odds of hitting what amounts to a skyscraper at under 5000 meters range.

On the other hand, if I re-imagine these as gatling weapons - 2 plasmas replace one at TL11, four at TL12, the fusion gun becomes an 8-beam gatling at TL12 and a 16-beam gatling at TL14 - then they start looking like they're getting an increased chance to hit because there are more firing, and their penetration stays around that of a beam laser, which simplifies things quite a bit (TL8 beam laser's a 70, 35 beyond 5 km; a pair of TL11 plasmas dividing 250 Mw between them come in at 77/38; a quad of TL12 plasmas dividing 250 Mw between them come in at 71/35; an octet of TL12 fusions dividing 500 Mw between them come in at 75/37; a ... sextidectet? ... of TL14 fusions dividing 500 Mw between them come in at 71/35.)