May 25, 2020

Aurora Tutorial Part 6

We've come through a lot of Aurora's economics/colonization gameplay, and it's finally time to talk about the really cool bit: warfare. This is an extremely complex part of the game, and while there are multiple feasible playstyles, it's also an area where it's easy to get things wrong and end up with a useless fleet. So before we start actually playing with the wonderful shipbuilding system, let's take a look at the broad overview of combat, which we will then flow down into how to build not just ships, but an integrated fleet.1

There are two types of weapons in Aurora: beam weapons and missiles. Beam weapons come in a number of different varieties. All have essentially infinite ammo (with a few restrictions) and are only useful at short ranges (~100kkm for beams, ~50mkm for missiles), meaning your fleet needs to be able to close with the enemy (this usually means higher speed than a missile fleet) and survive any missiles they can throw your way. Missiles have to be researched, built and transported separately, but offer you the opportunity to avoid beam combat. On the whole, I tend to prefer missiles, although this is as much an aesthetic as a practical choice, and many other options can be made to work.

Normally, this is the point where I'd go into a long discourse about the various roles of a fleet, and the importance of creating a balanced force to address all of these, but Aurora's diplomatic modeling and strategic AI are both primitive enough, particularly when combined with the jump point model, that the game tends to take on a very Mahanian flavor. Two fleets will enter a system and have it out, and the basic objective when building a fleet is to make one that is as effective as possible at dealing damage and surviving the other guy's attacks, on whatever budget you can afford. The exact implementation will depend on a bunch of details, ranging from your available tech and researchers to your long-term strategic plans and aesthetic preferences, but the basics are consistent.

Let's start with the most basic possible example of this. We'll ignore missiles for now (you should not actually do this or your fleet will die) and focus on beam weapons. There are three main types of beam weapons which you can build your fleet around, as well as four specialized types that are used for specific purposes. The three main types are lasers, railguns and particle beams. Lasers are the baseline weapon, with decent damage that falls off with range. Railguns fire four small projectiles, giving increased damage relative to lasers, but at a cost in range and armor penetration. Particle beams deal less damage than either type and have a shorter range than lasers, but suffer no damage falloff at all. The game when auto-assigning tech points seems to pick one of the three at random, and in practical terms, all are reasonably well-matched. Each relies primarily on three techs. One sets the caliber, which determines the size, base damage, and power requirements of the weapon. Another is the range multiplier, while the third determines how quickly the weapon recharges. The ideal weapon size depends on the role in question, but for a basic beam warship, the largest type available is probably the best.

Beam weapons need fire control. These each have a set range and a speed, based on racial technology, with multipliers that change range and tracking speed, along with size and cost. The tracking speed is the fastest target that a weapon can attack without penalty, and it's set to the lower of the racial speed tech (x1 multiplier), the ship's own speed and the speed of the fire-control system. Turreted weapons, which we'll come back to later, allow weapons to track faster targets. Weapon accuracy against a target slower than tracking speed varies from 100% at a range of 0 to 0% at the maximum range of the fire control. As a result, it can often be a good idea to build a fire control that outranges the weapons it is linked to, as it will have superior accuracy when a target gets within range. Weapons also need to be powered, and I'd recommend researching a reactor matched to your most common capacitor recharge rate, either for a single weapon or two weapons. This makes it easy to get the right amount of power without wasting space.

Another thing all weapons need is active sensors. If a target isn't being tracked by an active sensor, it can't be attacked, although that sensor doesn't have to be on the ship itself. Active sensors are defined by their resolution, which is the smallest contact they can easily see. It's measured in hull spaces (HS), units of 50 tons. Contacts smaller than the resolution can get closer to the sensor than the maximum range before being detected, while anything larger is picked up at maximum range. However, a smaller resolution means a shorter maximum range. For instance, a sensor with R100 might have a range of 18.5 mkm against anything 5,000 tons or up. However, against a 1,000 ton ship, it will have a range of only 740,700 km, and a 250 ton fighter will get within 46,300 km before being picked up. It's unlikely to pick up any missiles at all. An R20 sensor of the same size will pick up anything of 1000 tons or more at 10.8 mkm, and the fighter at 676,800 km. None of these will work particularly well against missiles, which require R1 sensors. A sensor of the same size as the previous two will pick up anything of 50 tons at about 4 mkm. Most missiles are smaller than that, and the sensor will pick up even the smallest missile at only 359,000 km. The usual result of all of this is to fit the fleet with a variety of sensors of different sizes and resolutions, depending on role. For a beam warship expected to operate with other ships that can provide large-area sensor capabilities, the best option is probably a small R1 sensor to use as a backup in case of emergency. Even the smallest of these sensors will outrange the ship's fire control.

But why bother with a sensor at all, given the emphasis on fleet operations? Two reasons. First, there's a chance you'll end up detaching the ship at some point and sending it off on its own. Second, one of the key components of warship-building in Aurora is redundancy. As ships take damage, systems are knocked offline, and Murphy's Law guarantees that any single point of failure will be the one hit. So every ship having a small active sensor makes it very hard for the fleet as a whole to lose targeting data. Likewise, I would never build a warship2 with a single fire-control, a single engine, or a single fuel storage. Any of those three getting hit takes the vessel out of the fight instantly.3

That's really all we need for a basic beam warship. You'll want to add some armor, and make sure to pay attention to maintenance life, fuel and deployment time, which all work pretty much like they do for other kinds of ships. Here's an example from one of my test games:

Moyote class Cruiser (P) 6,000 tons 219 Crew 681.3 BP TCS 120 TH 240 EM 0
2000 km/s Armour 3-29 Shields 0-0 HTK 47 Sensors 0/0/0/0 DCR 2 PPV 48
Maint Life 2.06 Years MSP 141 AFR 144% IFR 2.0% 1YR 44 5YR 662 Max Repair 60.00 MSP
Jaghunchi Control Rating 1 BRG
Intended Deployment Time: 6 months Morale Check Required

Nuclear Pulse Engine EP120.00 (2) Power 240.0 Fuel Use 81.65% Signature 120.00 Explosion 10%
Fuel Capacity 229,000 Litres Range 8.4 billion km (48 days at full power)

15cm Railgun V30/C3 (8x4) Range 90,000km TS: 3,000 km/s Power 9-3 Accuracy Modifier 100% RM 30,000 km ROF 15
Beam Fire Control R192-TS3000 (1) Max Range: 192,000 km TS: 3,000 km/s 71 67 63 59 55 52 48 44 40 36
Beam Fire Control R96-TS3000 (1) Max Range: 96,000 km TS: 3,000 km/s 67 59 52 44 36 28 20 12 5 0
Pebble Bed Reactor R3 (8) Total Power Output 24 Exp 5%

Active Search Sensor AS1-R1 (1) GPS 1 Range 1.3m km MCR 113.5k km Resolution 1
Active Search Sensor AS3-R1 (1) GPS 10 Range 4m km MCR 359k km Resolution 1

This design is classed as a Military Vessel for maintenance purposes

So far, it's all fairly straightforward. But there are two complications. First, there are the four kinds of specialized beam weapons I mentioned earlier. The one I use the most is the gauss cannon. This is the only weapon other than the railgun capable of firing more than one shot per 5-second increment, with the ROF depending on your tech level. It requires no power and unlike railguns can be fitted in turrets, making it perfect for missile defense. However, each shot deals only 1 damage, and its range is very short. The other two that see reasonable use are high-power microwaves and meson cannons. HPMs are reasonably effective against shields and bypass armor to attack electronics directly, although their range is limited. Mesons bypass shields and some armor, but do only limited damage. Both can be useful as backup to more conventional weapons, but aren't great for main armament. The last beam weapon is the plasma carronade, which does a great deal of damage at close range, but is generally pretty useless.

The second complication is missile defense. Unfortunately, this is a subject that requires extensive discussion, so I'll pick things up there next time.

1 From here on out, this tutorial is a lot less specific about specific actions to take. Everyone has their own way of building warships, and I'd encourage you to experiment.

2 This rule doesn't really apply to fighters or FACs of under 1,000 tons, which are semi-disposable.

3 Yes, you could apply this argument to suggest that the beam warship should have two active sensors in case it operates independently. Given the low size and cost of beam-compatible active sensors, this isn't a bad idea.


  1. May 25, 2020Alexander said...

    Presumably Railguns are also unaffected by damage falloff? So gauss cannons are basically CIWS, and the other three special types are effective against different types of defence (either ignoring or overwhelming armour and shields) but sacrifice flexibility?

  2. May 25, 2020bean said...

    Railguns do have damage falloff. (It shows how much I use them that I had to check in the game.) Gauss are basically for point-defense, although CIWS is a specific system in the game. HPMs and mesons are both useful as adjuncts to conventional weapons, but I wouldn't want to build a fleet around them. Plasma carronades are only really useful when you need to trick people into thinking they're defended. (Populations get antsy if there isn't enough firepower in their system. This can be annoying in a newish game where you don't have a backlog of older ships to keep them quiet while your main force is handling things at a distance. Low-recharge plasma carronades are probably the cheapest way to do that these days.)

  3. May 26, 2020Alexander said...

    Would plasma carronades have any value in a planetary bombardment scenario? I feel like a short ranged but powerful weapon ought to have some use, e.g. against anything very tough that has neither the speed to evade you or the firepower to stop you closing. I suppose it's realistic to have some technologies that are dead ends for development, but at you make them sound like a trap (one of many) for new players that otherwise never make an appearance in the game.

  4. May 26, 2020bean said...

    There was a massive overhaul to ground combat in C#, which I’m still working out the implications of. And I just haven’t done enough planetary bombardment to know what works best there. My current bombardment ship is laser-based, but it’s designed to hunt surface-to-orbit weapons. If you're going up against someone who can't shoot back, plasma carronades wouldn't be terrible, as they're smaller than lasers for the same damage and quite cheap (important because bombarding weapons fail 1% of the time and have to be repaired). I guess it depends on the target you're shooting at, which you can't really know in advance. If it's weak, then railguns are a better option.

    They can also be used if you want to RP the kind of people who use plasma carronades. I once played a game where my main weapon was a fleet of carronade FACs. Didn’t see serious combat, but it would have worked OK.

  5. May 26, 2020Commenter said...

    At first glance it seems like a recipe for Banner of The Stars style fleets: missile battery-ships backed up by a screen of laser defense boats, with combined missile+beam cruisers for independent operations.

    Also goodbye again captchas.

  6. May 26, 2020Alexander said...

    Well, you could also imagine small missile boats designed to attack from beyond sensor range, or a large and well protected beam armed combatant that can close with and defeat a static fleet defending a planet, or force a jump point. Or probably many other designs. If redundancy is important I'd be inclined to make sure my ships all had at least some beam weapon, both for missile defence, but also so there's still something you can do once the missiles run out.

  7. May 26, 2020bean said...

    There's a lot of options which will work reasonably well. Missiles can be staggeringly effective, but getting the most out of them is pretty micro-heavy, and you run out. Also, replacing them can get expensive. Beams are balanced to the point that you can avoid these problems without suffering a huge penalty.

    Missile boats are likely to have issues with FC range. It's definitely possible to build a beam ship capable of closing through missiles. I've done it in my current game. It's just really annoying, and I think my next fleet will be heavier on missiles to spare me that. And because I like missiles.

    (Every fleet in Aurora is a reaction to the problems of your last fleet.)

  8. May 27, 2020echo said...

    Semi off-topic, but did anyone play Starfire? It looks like Aurora split off in 3rd edition over the depth of campaign mechanics vs the pen and paper rules.
    Suppose there's not much of a playerbase for play by mail strategy games any more.

    Remembered the other day that I'd read two of the White & Weber tie-in novels in middle school. Really awful schlock, but the random connection was neat.

  9. May 27, 2020bean said...

    Aurora V1.10 just came out. The database will need to be updated if you want to use it, and I'd recommend doing so. The changes made won't affect anything discussed here (that probably won't really happen until we get V2.0 or V3.0, because of how Steve handles changes) so you should be fine with continuing as-is.

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