This post reports the results of an effort to learn more about the effect of range on non-missile weapon damage, as of Aurora 6.20. It follows up on a conversation in the ship design forum.
The basic question we ask here is
"What is the damage output of the basic energy weapons, at every range, at a given tech level - and what does comparing damage outputs tell us?"NOTE: This analysis is for version 6.2 of the game, and therefore does not take into account shock damage. Shock damage has (will have) the effect of making powerful missiles, lasers, etc. more potent.
The technological level we test under is one where all tech up to a cost of 33,000 is researched, and all resulting designs are known. This seemed a reasonable mid-game simulation; other are certainly possible and perhaps better.
To start off with, we need a definition of damage output. Raw damage matters, of course, but so does hit chance (within the weapon's maximum range, this is solely determined by the fire control), the size of the weapon, and the rate at which it fires. Therefore, we create a unit, call it "damage density", and define it as being
(raw damage) / (game tick of 5 seconds) * (base hit chance, before crew training and target speed modifiers) / (size of the weapon, in hull space units of 50 tons)
We now need to consider that some standard beam weapons penetrate more deeply into armor than others. Without getting into excessive detail here, our calculations give higher weights for deeper damage (and you can modify them depending on the enemies you face).
Notice that we here consider only rate of damage, and ignore alpha strike (first-strike damage). In Aurora, there are several ways to insta-kill (or -incapacitate) an opponent, but multiple-round slugging matches are more common between opponents of equal tonnage and tech level ... or when you're outmassed by the AI, but not outclassed! Both situations are considered here.
This game setup, these definitions, and all calculations are available in the form of a Google spreadsheet (
https://docs.google.com/spreadsheet/ccc?key=0AsD-qMl9uc6cdFR5MlRySkhXUGxYT1BxNVdCRUpLOGc#gid=0) and the original Excel 2010 worksheet (attached). A variety of weapons in each of the categories Microwaves, Mesons, Lasers, Railguns, and Particle Beams were designed. Carronades are not included in the calculations, but are mentioned below. Plasma torpedoes are not considered. All designs were optimized for at least one of damage, range, rate of fire, weapon size, and cost. Designs include every size of weapon available at this technology level for all weapon types considered except for particle beams (in which case doing this proved unnecessary).
The weapons are supplied with a beam fire control (FC) of 4x size and range, the maximum Aurora allows us to design. We here ignore the size, cost, and research price tag of such an FC (although it certainly needs consideration, especially for smaller ships) and consider only the weapons themselves. The hit chance of this FC at every range are included in our calculations.
For details on weapon, FC, etc., consult the spreadsheet. Here, we're just going to show the graphs and talk about what they tell us. If the pictures are blurry, blame the forum software ... and open the images in new tabs.
MICROWAVES
This, the first of our graphs, shows the damage output of a variety of microwaves, as a function of weapon range. The highest damage density is normalized to a value of 1 and all weapons' damage density adjusted accordingly. So, if a particular weapon has a rating of 0.45 at a range of 160 k km, that means that,
for every 1 damage, per tick, per HS you devote to the best possible weapon against targets at a range of 10k km, at a range of 10 k km, using the tested fire control (described above), ...
you can do 0.45 damage, per tick, per HS you devote to this weapon, at a range of 160 k km, using that same fire control.
The first point that needs to be noticed is that damage output drops off sharply with range. There are three reasons why it does (and a fourth for certain other types of weapons):
1. Fire control accuracy is range-dependent; more specifically, accuracy drops off linearly with range, reaching zero at maximum range. The maximum range of this fire control is 384,000 km.
2. One of the factors in weapon range is weapon size. Larger weapons take up more Hull Size units, which means you can mount fewer of them in any given tonnage.
3. Larger weapons fire more slowly (depending on your level of Capacitor Recharge tech).
4. Laser, railgun, and carronade damage drops off with range.
So important are these points that our entire discussion essentially amounts to showing how they, and the Aurora game rules, interact. The single most important of these rules is that a weapon does not save up energy between game ticks - and the difference between a gun that fires every tick and one that fires every two ticks is huge.
Let's consider some cases:
A. The weapon "R9/C3" is the superior choice at ranges <100k. This is a microwave designed by asking "What's the longest range I can get on a weapon that fires every game tick and has the smallest footprint?" Because larger microwaves don't do more damage per hit, this weapon beats - within its effective range - anything with a slower rate of fire or a larger footprint. If you sacrifice some range, you can field weapons that are even cheaper to research and build.
B. The weapon "R18/C6" is potent at ranges from 100k to 160k km. It was designed by asking "What's the longest range I can get on a weapon that fires every game tick?". The answer takes up 4 Hull Space, which drops its effective damage output, but nothing that fires more slowly can match it within its range.
C. The weapon "R40/C6" is pricier, and offers much lower damage output at close and medium range as its a bigger weapon that fires more slowly, but can reach out and hurt things to the limit of the fire control.
D. The weapon "R72/C6" is inferior at all ranges. It's based on a higher tech level, and costs more to build, but more is often worse in Aurora. Why? This maximum-size weapon out-ranges the fire control (so all that extra range is wasted), takes up more HS, and fires more slowly. In short, it's a white elephant in the current version of the game. The only way to make it serve any purpose is to tech up your fire control tech one or two levels (spending double the research points each time) past your weapon tech level.
MESONS
For the purposes of evaluating the effect of range on damage output, mesons work very similarly to microwaves. There are are just a few differences in this graph, none of which need extended explanation. Again, we see the superiority, at any range, of the smallest, quickest-firing weapon capable of reaching out to that range, and the inferiority of any weapon too long-ranged for the fire control.
LASERS and PARTICLE BEAMS
This is a bigger graph and there are several points of interest.
We are now also considering weapons that do increasing amounts of damage with size. We also need to consider armor penetration. Weapons other than mesons and microwaves are stopped by armor, and their armor penetration patterns differ. The deeper the penetration, the more likely at least part of a hit will pierce into the vitals of a ship. Therefore, lasers (and carronades), particle beams, and railguns have all had their penetrations recorded in tables, and each point of damage is multiplied by a armor depth factor that ranges from 1 to >3. For details, or to adjust these multipliers, consult the spreadsheet.
With this introduction out of the way, let's consider individual weapons - first lasers, then particle beams.
A. The 10cm, 12cm, and 15cm lasers each fire every game tick, and we use the lowest (and least expensive) capacitor recharge rate needed to make this possible. The 10 cm and 12 cm are only competitive at very close range. The 15 cm quick-firer, the weapon offering the best damage output of any tested laser at every range except at 200 and 380 k km, was designed by asking "What is the highest-damage, longest-ranged weapon we can field that fires every game tick?".
B. At this tech level, no other laser competes, but it's still worth pointing out that mounting the biggest, longest-ranged gun available (30 cm C6 Soft X-ray) is a decent second-best option at medium and long beam range because of its high per-weapon damage output and good penetration (the details depend on the multipliers we use for penetration, but the global point is valid for any reasonable multipliers), and the fact that its energy requirement is an exact multiple of the best available recharge rate. Against this, we note that it is both research-intensive and costly.
Unlike with microwaves and mesons, increasing the weapon range displayed on the component design window past the range of the fire control is advantageous. Because lasers lose damage with range, and this damage drop-off is dependent on the range multiplier technology used, weapons designed with higher range multipliers outperform at range. The damage a laser (or carronade) does on a hit at every range, and which is shown in the ship design summary, is the minimum of:
a) weapon maximum damage, and
b) (weapon range, as listed in the tech design window, not the ship listing window) / (combat distance), rounded down to the nearest integer.
We promised to mention Carronades earlier and now's the time to do so, if only to (mostly) dismiss them. Carronade weapon damage at range uses the same (or similar) rules as does that of lasers. Because the base range of carronades is so short, and they don't recharge any more quickly or take up less hull space, carronades are never competitive with lasers beyond closest range - usually 10 k km (even at 20 k km they are usually crippled). Their advantages are are that they need one fewer research path to develop, cost a bit less to field, and require fewer crew. I have not investigated their penetration patterns.
PARTICLE BEAMS
Particle beams are plotted relative to lasers, as their damages can be compared directly. We immediately notice that they outperform lasers, at this tech level, between 200 k km and 320 k km (between 140 k km and 320 k km if we set aside the 15 cm quick-firer). The reason for this is that particle beams don't lose damage with range.
Particle beams benefit from having ranges well-matched to the maximum beam control range at the same technological level. The fact that we don't need to research their weapon size tech past the first few steps (just enough to keep pace with capacitor recharge rate) is another advantage. They do however, no damage beyond their maximum range, so improvements in sensor tech that permit longer-ranged beam fire controls have to be matched with improvements to the particle beam range tech.
We also notice that, just as with microwaves and mesons, it is counter-productive to field weapons too large to fire every game tick. Such weapons require more technological investment, cost more to field, and are too large and too slow-firing to compete - as of Aurora 6.2, at this tech level - even if, as is the case with particle beams, they do more damage and penetrate more deeply.
RAILGUNS
Because railguns are also affected by armor, and because we have also determined railgun penetration patterns, we can plot railgun damage density as a function of range on the same scale as we use for lasers and particle beams. When we consider a variety of railguns and compare them to the best two lasers and the best particle beam, we notice a few new wrinkles on the observations previously made for lasers.
A. The weapon designed by asking "What is the highest-damage, longest-ranged weapon we can field that fires every game tick?" outperforms all other options only at close range (in this case, up to 40 k km and at 100 k km).
B. As we increase the size of our railguns, we steadily lose close-combat damage density (as before, due to larger size and slower firing speed), but gain long-range damage density. Taking this analysis a step further, we notice that the 20 cm railgun is a solid overall option at medium range, the reason being that it takes full advantage of the highest available capacitor recharge rate; some competing designs can not at this tech level.
Railguns are never the best choice for beam combat at any range - either the best laser or the best particle beam always outperforms the best railgun at all ranges - but railguns are never too badly outclassed. These comments will depend somewhat on the penetration multipliers we assign. More generally, when we recall their superior ability to stop missiles, it's clear that quick-firing railguns are a legitimate option for dual-purpose combatants.
ALL WEAPON TYPES, COMPARED
We wrap up our evaluation of beam weapons at this technological level by asking the question we really wanted to in the first place: "What weapon types perform best at each range, at an equal technological level?"
In order to compare mesons, microwaves, and standard damage weapon in the same plot, we need to continue to consider damage densities relative to the damage density of the same weapon type's best option at 10 k km (point-blank range). We then define a new term, the "damage density frontier", as being the graph of the relative damage density of the best weapon of each type, at each range. For most weapon types, several weapon designs contribute to this curve. For particle beams (and almost for lasers) only one does.
What matters in battle is maximizing your advantages and your opponent's disadvantages. We therefore want to find ranges that enable particular types of weapons to outperform. A look at this graph tells us the following:
A. Particle beams are least effective at close range, but are relatively most potent at ranges between 220 k km and 320 k km (at this particular tech level), a broad enough range that it is practicable for a warship to maintain a optimal firing distance (depending on relative speed and relative commander Initiative ratings).
B. Lasers and railgun relative damage density falls off sharply into medium range, with railguns suffering somewhat worse. By contrast, mesons and microwaves remain relatively strong at ranges between 80 k km and 160-180 k km. Therefore, if you want a warship armed with railguns or lasers to compete with opponents armed with either mesons or microwaves, either blaze away at point-blank range or play at long bowls. Maintaining a happy middle ground is the preferred tactic of the meson or microwave enthusiast.
This completes our evaluation of the effect of range on the damage density of non-missile weapons. We've learnt, or at least usefully reminded ourselves, of the interaction between weapon characteristics, the power and limitations of beam fire controls, and the Aurora game rules, particularly those relating to actions and the passage of time. That said, this present study has several investigative limitations. Perhaps the most important is the assumption of a single, common technological level.
