Shouldn't bigger missiles be more effective than small ones?
No.
Now, let's make it 8 times bigger:
[...]
The missile did not become "better" than 8 small ones. It does better in some fields but looses in others.
Yes.
This is how Aurora is designed and how things are supposed to work. There is not supposed to be one clearly better option, rather there should be a range of options which can be viable in different situations. If bigger missiles are more effective than smaller ones, why build smaller ones (except for AMMs)? No, the game balance is better if bigger missiles are better in some cases, and smaller missiles are better in other cases.
Additionally, there are a couple of key misconceptions in your post:
Is longer range and damage concentration good enough reason to not just spam small missiles?
Longer range, in and of itself, is acutely valuable. In simple terms, if you can shoot at the enemy from beyond the range at which the enemy can shoot at you, then you have a great tactical advantage as you can fire without being fired upon. If your ships also have sufficient speed to maintain the range, you are effectively invincible unless your enemy deploys a longer-ranged missile in turn.
The downside, of course, is that a longer-ranged missile will generally be less effective as greater sacrifices must be made to achieve that range, more MSP must go to fuel and/or the missile must be slower to achieve better fuel efficiency (slower missile = harder to beat enemy point defenses).
There is one enormous downside to using big missiles instead of many small ones. And that is reload rate.
Reload rate only matters in some specific cases:
- The main one is for AMMs, when you typically need the fastest reload rate you can get to put as many birds in the air as possible, particularly when defending against box launcher volleys.
- A niche edge case, at least against NPRs, is that you want a faster fire rate if trying to eliminate a wave of fighters or FACs before they close to their own attack range.
Notice that both of these cases have something in common: you are not usually concerned with the enemy's point defense in these cases (missiles have none, while fighters only have PD if they are using railguns or Gauss cannons as weapons which is not the most common setup for fighters). This is because in all other cases, the most important maxim of missile warfare is this:
Missiles are only as good as their ability to defeat enemy point defense.Everything else is secondary - this is not to say everything else is unimportant, but it is clearly secondary - missile range, accuracy, damage, etc., none of this matters if the enemy can reliably destroy all of your missiles before any one of them hits a target. Notably, this means that the biggest variable in favor of offensive missiles is not the reload rate (which is almost completely irrelevant, outside of the above cases) but rather how many missiles you can fire in a single volley of fire.
This is why most players will claim that box launchers are the most powerful form of missile launchers, because they are the most compact which means you can fit more into a given tonnage and thus launch more missiles at once. Note that box launchers have an incredibly high reload rate of, um,
nope. The fact that the launcher type that cannot even reload in combat at all (aside from rare situations in defense of the same point at which they reload) is considered the most tactically effective form of missile weaponry tells us that reload rate does not matter at all compared to the ability to maximize the number of missiles on target at a single moment.
So why use any other kind of launchers? Because different options are better for different situations. There are specific cases where fast reload rates do matter, I listed two above, and in these cases you need to launch faster to get as many missiles into space as possible. Another option is using 30% size launchers, these are not as space-efficient as box launchers but offer far better strategic flexibility - without magazines, they can be reloaded
in-situ by a collier, and with magazines you have a greater total throw weight before needing to reload. If you can achieve local tactical supremacy, so that even with only one-quarter as many missiles in a volley you still overmatch the enemy's PD, then that strategic flexibility becomes desirable.
With this in mind, let's return to the missile designs in the OP:
Comparing eight of these:
Missile Size: 2.60 MSP (6.500 Tons) Warhead: 6 Radiation Damage: 6
Speed: 36,923 km/s Fuel: 250 Flight Time: 60.1 seconds Range: 2,219,078 km
ECCM-3 ATG: 40%
Cost Per Missile: 4.45 Development Cost: 333
Chance to Hit: 1k km/s 516.9% 3k km/s 172.3% 5k km/s 103.4% 10k km/s 51.7%
to one of these:
Missile Size: 20.80 MSP (52.000 Tons) Warhead: 48 Radiation Damage: 48
Speed: 36,923 km/s Fuel: 2,000 Flight Time: 3 minutes Range: 6.28m km
Decoys: 7 ECM-3 ECCM-3 ATG: 40%
Cost Per Missile: 38.75 Development Cost: 984
Chance to Hit: 1k km/s 516.9% 3k km/s 172.3% 5k km/s 103.4% 10k km/s 51.7%
The larger missile has, as you say, effectively the same ability to beat enemy point defense as the eight smaller ones (as long as we gloss over the intricacies of EW mechanics), and delivers the same damage, etc., but has longer range. So, the larger missile would seem to be... better? Indeed, it is better in a case where reload rate does not matter, e.g., as an anti-ship missile used against enemy large warships. If reload rate matters, then the small missile may be preferable, e.g., as an anti-fighter missile.
So, we have two different missile designs which have similar effectiveness but each shines in a different situation. Cool, that's exactly what we wanted!
This is how Aurora is designed and how things are supposed to work. There is not supposed to be one clearly better option, rather there should be a range of options which can be viable in different situations.
Looks like the game design works as intended.
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As an addendum, I do want to note that bigger missiles can be designed with a better approach than in the OP, because of the fact that larger engines are more fuel-efficient we have some flexibility in designing them. Since you did not provide the tech levels and MSP allocations for the missiles in the OP, I will not attempt to reproduce them, but I will follow a similar approach and look at different sizes.
I will use these tech levels:
Warhead Strength 5 per MSP
Ion Drive Technology
Fuel Consumption 0.6
Maximum EP Modifier x2.5
ECM 2, ECCM2, ATG 0.32 - not relevant but listed for completeness
Let's consider a size-4 missile design as our reference:
MSP: Warhead 0.8, Engine 2.24, Fuel 0.46, ATG 0.25, ECCM 0.25
EP Modifier x4.10
Damage: 4
Speed: 28,750 km/s
Range: 29.99 m km
%CTH vs 5000 km/s: 75.9%
ECCM-2
(I am using a homebrew missile calculator instead of setting this up in the game, so I apologize for any inaccuracies.)
Now let's consider a size-8 missile, twice as large, with a similar design specification except we will use a decoy to maintain the same effective number of targets (again, neglecting EW mechanics details):
MSP: Warhead 1.6, Engine 4.48, Fuel 0.92, ATG 0.25, ECCM: 0.25, Decoy 0.5
EP Modifier x4.10
Damage: 8
Speed: 28,750 km/s
Range: 42.30 m km
%CTH vs 5000 km/s: 75.9%
Decoys: 1 x ECM-2
ECCM-2
As we already saw, this gives us a missile that has more or less the same performance profile as 2x size-4 missiles, but with 40% greater range in exchange for a lower rate of fire. However, we have options here to change our design approach.
For example, what if we only want 30 m km range? Maybe our sensor technology isn't good enough to use the full 42 m km of the above design, for example:
MSP: Warhead 1.6, Engine 4.48, Fuel 0.92, ATG 0.25, ECCM: 0.25, Decoy 0.5
EP Modifier x4.45
Damage: 8
Speed: 31,150 km/s
Range: 29.99 m km
%CTH vs 5000 km/s: 82.24%
Decoys: 1 x ECM-2
ECCM-2
Now we have a missile which has the same range as the size-4 missile, but it is
faster - therefore, it has a better chance to hit the target, and a better ability to evade enemy PD.
There are other possibilities: we could use a larger warhead, yielding missiles with similar speed and range but bigger hitting power (my calculator gives me the same speed and 27.1 m km range with WH 10, for instance; +25% hitting power for -10% range is a fair tradeoff). We could add an additional decoy, trading a bit of speed or range in exchange for better PD evasion (with 2 decoys, the first size-8 missile design drops to 27,325 km/s, losing about 3.8% accuracy in exchange for 33% better PD evasion; this is a very good trade!). The efficiency of larger missiles gives us a lot of options to be better at one thing or another, whereas smaller missiles are more limited in what can be achieved in their designs.
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As a last note, I want to mention that the mechanics of electronic warfare (EW) are important here. I have alluded to this a couple of times (by neglecting it), but it complicates the analysis considerably since the relative differences in ECM/ECCM tech levels between opposing forces can tilt the balance one way or the other, sometimes quite strongly. If the enemy ECCM is better than your missiles' ECM, then decoys will be less effective and smaller missiles will be more attractive as a way to correct that imbalance. On the other hand, if your ECM tech matches or exceeds that of the enemy, then larger missiles become more attractive, since mounting decoys (0.5 HS each) is often a more efficient use of MSP than firing more missiles.
Also left out of this discussion is the topic of multiple-stage missiles including MIRV-like designs, which can be an interesting approach to achieve a mix of both range and effective striking power. MIRVs in particular can evade enemy PD by firing a larger number of small missiles with short range from a slow, long-range first stage - you lose some overall efficiency in terms of raw tonnage to accomplish this, in exchange for an extremely long engagement range that probably precludes any kind of enemy return fire (unless they also use MIRV-style missiles, which NPRs do not as far as I know).
These last points underline my main point above: in Aurora, there is not meant to be any kind of weapon which is better than all others. Rather, the game is meant to provide a range of options, each of which may be good in different situations. Missile design in versions 2.2+ largely accomplishes this design goal as long as the player is smart about how they design their missiles, and rewarding careful thought and intelligent decision-making is what Aurora is really all about. Therefore, there is not really any need to buff larger missiles, rather what is needed is creativity and wisdom on the part of the player to make the best use of these weapons.