Point Defense Brain Dump - Area Defense vs Final Fire

[Potat999 (OP)]

I spent the last few days fiddling with some spreadsheets to try to figure out the optimal missile area defense/PD layout for a given tonnage.  I came to a few tentative conclusions which surprised me a bit and wanted to bounce them off you guys to see if they pass the sniff test.  Sorry in advance for the rambling post, I'm mostly just trying to organize my own thoughts hoping somebody will be bored enough to read through it and poke holes in any obvious errors .

I found this super useful thread from way back in VB6 which had a derivation of hit chances for pure final fire vs area defense with a factor 'A' representing all non-range to hit factors (tracking speed, tracking time, etc.) which should be basically the same in both cases.  I'm standing on the back of giants here and just assuming their math is right, it looked OK to my eye -  http://aurora2.pentarch.org/index.php?topic=5197.0 

Has there been any such discussion for C#?  If so, I must have missed it - please point me at the thread . 

Anyhow, at the time (2012), they concluded that Final Fire was superior in all cases, even with lasers, and easier to boot as it would work for a single big fat stack of ships.  However, looking at this, one major factor has changed since these numbers were crunched - BFCs are smaller now, and FF vs AD BFCs are closer in tonnage. 

This leads to a few differences from the VB6 case with the same 1400 T payload, tech, missile speed as they discussed (I assumed fractional guns for ease of calculation):
- higher beam PD efficiency overall in C#
- a slightly better Area Defense (AD) performance for 10mm Lasers vs Final Fire (FF) (7.65A vs 7.16A)
- a slight advantage in some cases to increased BFC range modifiers even for Final Fire, at least with higher ton/shot weapons.  A 2x range 200T BFC and yields a FF efficiency of 7.166A vs 6.85A with the 100T 1x.
- For lower weapon counts (<~3/~450Tons) a .6-.9 range BFC may yield superior hits/ton in final fire mode.  At ~4+ weapons a 1x range BFC seems ideal for FF and for very large banks of weapons a 2x-3x range BFC may be ideal for FF for the slight to hit-advantage.  Also, a 2x-4x range BFC will greatly increase mid-range accuracy for systems like lasers which may also be used against other ships.

Notes: I think missiles are a bit slower in C# due to the engine changes, correct?  Maybe I should plug in a new missile speed to be more consistent with this ~4000RP cost low tech example? 

I totally eschew power plant tonnage, crew tonnage, and turret tonnage here since I kind of assume it will be 'small' and 'similar' across these cases, this may be a terrible idea but I'm lazy.

In the old thread linked, they made a low tech comparison when 10cm lasers.  Once capacitor 6 is reached, a 15cm laser can give 2x the range at 1.33x the tonnage, and in this example case the range impact will increase the laser AD efficiency vs 10cm lasers to 7.97A, at least for these missiles and all other techs equal.  I neglect the 2x power need, which might matter a bit, but efficiency seems pretty similar for the 10cm and 15cm case.  I think there is another bump to AD efficiency/ton possible at ~12,25 Cap Recharge where a 10cm, 15cm x.75 laser could have ROF5, but this is probably quite expensive and may not be practical. 

EDIT: Oops. I trusted the wiki sizes for beams but C# sizes are 3, 4, 5 HS for 10,12,15 not 3,4,4... this changes things a lot :S.  Since there is no big nonlinear bump in range/HS in C/#, 10cm stays the most efficient (due to more shots and all shots at closer range, hence better accuracy) for area defense.  At larger salvo sizes 12cm and 15cm start to get close, since BFC weight becomes negligible, but they still aren't quite as good.  In my 1400T case I now get 7.65A, 6.87A, 6.37A for 10,12,15. 

So, does this mean AD is now superior to Final Fire?

Well, not really.... just for lasers, against these particular missiles.  The calculation is very sensitive to speed. This strong dependence on relative missile speed means your direction of travel will be very important.  In this low tech example, the +/- 4km speed of your ship into or away from the missiles may impact your AD efficiency by +/-20% - so keeping the range open gives 40% higher AD efficiency (~9A) vs closing (~6.5A).  When closing in this example, it would be more efficient to blob up and switch to FF mode rather than running a spread formation with advanced AD.

For Gauss or Rails with shorter range, FF is basically always better except with very slow missiles, as you would expect.  (Random note - bigger (>=15cm) rails might actually be better in AD than FF as well, but not sure this would ever really come up since they will still be way worse than 10cm on FF)

For a similar low tech example, consider 8.667 10cm rails and a 100T 4x range 1x track BFC to maximize to-hit.  Even at 1x tracking (say on a station), I get a PD efficiency of 8.2A due to the smaller 1x tracking BFC needed, meaning more guns in addition to 4x the ROF of the laser FF case leading to slightly more hits overall in final fire mode. 

This is neglecting the tonnage savings of not using turrets, and that a ship speed somewhat over the minimum BFC speed would allow for a 1.1x-1.25x track BFC for the rails and thus a to-hit chance >25% of the turret to hit chance, which with 4 shots might push rails up to ~10-11A vs lasers ~7-9A. It also neglects that for a high accuracy ‘A’ you might want to add another BFC to avoid overkill, which would push efficiency back down ~ 8%.     

It appears that high ROF (4+) turreted Gauss in FF mode is King of PD.  Considering a higher tech case with UV 15mm lasers & 400T BFC vs ROF4 Turreted Gauss with 100T FC vs a 48kkm/s missile, I get a similar ~6-9A for laser AD (closing range vs opening) to the low tech case vs ~13.115-15.5A for Gauss PD.  This Gauss range is based on 1-3 100T BFCs - for a high value of A (near 1), smaller expected volley sizes with multiple volleys/intervals will require more BFCs and push down Gauss efficiency/ton, but probably not enough to get back down to laser AD efficiency.

Again I didn't even consider power plant tonnage, so really Gauss PD efficiency would be somewhat higher vs lasers than shown.  And again the laser AD efficiency is really sensitive to speed - against a lower tech 24km/s missile AD efficiency will go up 2x and approach the gauss efficiency.

Anyhow, to summarize my findings :

- Using lasers in Final Fire mode is not very efficient compared to other weapon options.  Standard (full size) 10cm Lasers are worse for Final Fire not just than Gauss, but also appear worse than unturreted 10cm rails, assuming you are just trying to protect one task group. 
- Lasers in FF mode are so inefficient compared to Gauss at higher tech ROF (and maybe rails at higher track bonus) that two task groups would likely be better off covering themselves with gauss/rails rather than mutually interlocking lasers set to FF.  You might need 3-4 mutually supporting task groups at large spacing to justify using lasers in FF mode vs other weapons options. 
- Laser as a screen in Area Defense mode may be better than lasers in FF mode, but it seems very situational depending on your opponents missile velocity and your velocity.

- Lasers in AD mode have similar (at low tech) or lower (at high tech) efficiency to other weapon options in FF mode. Thus, the main draw of smaller lasers should be for their potential utility against other targets rather than pure PD utility. 
- Since lasers utility should be considered instead of pure PD efficiency, 15cm @ 6 cap on an escort in advance of the fleet may be the way to go - they appear to give a ~83% efficiency in AD mode (&60% in FF) compared to 10cm lasers while giving more utility for pew-pewing other ships.  For pure PD efficiency, 10cm would still be best if you are doing a pure laser playthrough and need more PD oomf without cheating and going to gauss. 

- Lasers set to AD in the main body (and so only able to engage inbound missiles and not missiles that pass them moving towards other targets) will be super duper inefficient vs FF mode unless the missile is hecka slow.  You probably should not do this (I was doing this, lol).


Brainstorming some doctrine ideas for a laser focused playthrough based on this finding:

- It may be safest to start in FF mode in one big ball to guarantee some hits if the enemy missile speed is unknown.  If speed is found to be low, PD escorts could be broken off to screen while you back away to open up the engagement envelope- if not, they could stay put in FF mode and you can close with the enemy, since relative motion is irrelevant to FF efficiency (except perhaps to spread out the incoming volleys over more intervals in a very dense threat environment). 
- I should probably roll in at least some Gauss PD to address fast missile threats if I encounter them.  It might be worth rolling in some 10mm rails for FF defense as a patch until I reach Gauss ROF3-4. 
- A formation with inbound missiles -> Laser Escorts (AD) -> Gauss Escorts (FF) -> Main Body all in line astern moving away from the missiles, such that the Gauss FF fire can cover both the Laser AD escorts and the main body might be viable.  The longer FF range would not hurt the gauss much, but the smaller engagement envelope would impact the AD lasers significantly - perhaps 22%,40% for 10cm, 15cm beams respectively.
- If 10-15cm lasers are 'optimal' for area defense - 20cm are suboptimal but still ~50-70% as effective at Cap10 due to their slightly longer range.  Maybe at high tech just forget about differentiating 'PD' and 'Anti-Ship' lasers, throw skads of high cap 20-30cm beams in quad turrets with fast fire controls, and just shoot whatever happens to be in range at a given interval?  Even a 2x Track BFC and Turret would potentially give a 20-30% hit chance vs missiles (with tracking bonus) while allowing you to demolish smaller craft and sandpaper down armor.  The raw DPS would not be bad since the ROF is high.  You would do a lot less armor pen and shock damage compared to very large lasers, but a darn sight more than a dedicated PD 10mm laser.

[brondi00]

I don't see anything odd or strange about this.  I've played a lot of aurora, both vb and c#.

Your info more or less jives with what I've experienced.  I do sometimes use lasers as a dual purpose (DP) weapon for RP reasons but rails and gauss are better PD weapons and rails are better DP weapons even though they can't be turreted.

Gauss is king, especially at 3-5 ROF (depending on what other research youve done in that playthrough).  Put it in FF mode and as long as you have enough turrets it will mow down missiles to the point you can almost ignore missiles except in very high threat environments (amm spam).

I appreciate you trying to quantify it with math.  And I so find it interesting, but, this game really is more about RP.  I'd encourage any new players reading this to really just pick one or two beams to use and use them and don't worry about what is most efficient.  If you do that you really take the fun out of the game.  My current play through I'm not using any missiles.  Particle beams/lances and gauss only and no ships under 5000t allowed.

I have had playthroughs where I only used lasers and nothing else.  Even on PD mode.  Yes that made it harder (more fun), but I also progressed pretty far in laser tech since I dumped all my offensive research into that.

Anyway thanks potat.

[Nori]

I've always heard of (and used) lasers in area defense as being a defense in layers option. You set it up not because its good per se, but because it is one more layer you can put in without a huge amount of cost, plus it doubles as a close quarters (or planet bombardment) weapon.

[Potat999 (OP)]

I appreciate you trying to quantify it with math.  And I so find it interesting, but, this game really is more about RP.  I'd encourage any new players reading this to really just pick one or two beams to use and use them and don't worry about what is most efficient.  If you do that you really take the fun out of the game.

Eh, games can be about both RP and min-maxing with math, if that's what floats your boat.  I'm playing with two PRs so if I thrash the AI too hard with my munchkining I can always fight myself.  One of my PRs went full box launcher madness so the other kinda needs to figure out how PD works STAT . 

Also I may or may not have turned on all the spoilers not knowing what they did... so I might need to minmax a bit.

[brondi00]

With min maxing you will find that even the most powerful spoiler is no match for you. 

I always leave them all turned on and unless a certain one shows up early game I never worry about them.

Playing against yourself by RP'ing several different empires is a lot of fun and usually more challenging since you can let them all specialize in different ways and min/max in different ways.

Have fun

[Jorgen_CAB]

Lasers are a pretty good DP weapons because say a 15cm lasers is effective at all types if beam combat not just PD in final fire mode but also at area PD and pure beam combat. Small railguns are decent PD but not very effective in beam combat. Medium caliber railguns might still be decent PD but still not that good in beam combat.

There is a reason why we usually recommend lasers as you weapon if choice if you only want to invest in one weapon system. Railguns is a good choice too though... a bit better in PD but lack in powerful beam fight in comparison, even if railguns have more DPS than lasers.

No beam PD are really good at mass box launched salvos. At some point you need role-play to balance the game. The game have too many mechanical loopholes for min/max play.

[Potat999 (OP)]

No beam PD are really good at mass box launched salvos.

Hold my beer, now I gotta try 

Serious tho the box launcher cheese was the best idea I had for my under teched conventional start PR to pose a credible threat to my TN  laser based PR, since any beam range engagement will get them thrashed with their puny low tech armor.   So now I'm in a PD layering & ECM vs salvo count/size and ECCM arms race with myself, haha.  I'm not actually sure who's in the lead, guess I need to run some wargames.

[QuakeIV]

I still insist that box launchers are not some kind of 'loophole', it makes logical sense that any device capable of being able to massively front load firepower that would otherwise get intercepted would have an advantage, and box launchers are that sort of device.

I also think it should probably be possible to do something similar on the beam PD side, but the missiles being useful in their own right is in no way a loophole because it stands to reason that they would work that way.

[Droll]

I still insist that box launchers are not some kind of 'loophole', it makes logical sense that any device capable of being able to massively front load firepower that would otherwise get intercepted would have an advantage, and box launchers are that sort of device.

I also think it should probably be possible to do something similar on the beam PD side, but the missiles being useful in their own right is in no way a loophole because it stands to reason that they would work that way.

I suggested some sort of AOE microwave pulsewave variant that I think might be useful for targetting whole salvos but Steve seems to believe that missiles are already too weak so he is hesitant to make anything that strengthens beam PD.

[Jorgen_CAB]

I still insist that box launchers are not some kind of 'loophole', it makes logical sense that any device capable of being able to massively front load firepower that would otherwise get intercepted would have an advantage, and box launchers are that sort of device.

I also think it should probably be possible to do something similar on the beam PD side, but the missiles being useful in their own right is in no way a loophole because it stands to reason that they would work that way.

The problem is balance but in my opinion also reality... in real life there are rarely such a thing as 0 and 1 mechanics as this is. For example it is nearly impossible to make launchers of this type to expend all the ordnance at the same time... the more launchers on any one platform the less likely it is they can all be launched at the same time for many different reasons... be it physical or electronic reasons. It just are quite unrealistic that you ever could launch 50 missiles at the same time from the same smallish platform even under the best of circumstances with all the complications it would make even if we talk about sci-fi there will be limitations and that is the problem with the mechanic as it is unbalanced without them.

In reality when military talk about being able to overload enemy point defences in naval warfare it is nothing like in Aurora. You want to have missiles coming in through as many vectors as possible and in as many tight waves as possible. The more vectors it becomes increasingly difficult for weapons systems to target and defeat incoming threats. This is both a mechanical and electronic or sensor issue.

The main issue with missile warfare is one of balance in relation to fire-controls and the salvo mechanics. If this was redesigned then box launchers could become a more reasonable weapons and you would only use box launchers on smaller platforms where they make more sense. Not even Harpoon launchers on naval warship can be considered a box launcher as they can be reloaded at sea. The mark 41 VLS could be reloaded at sea if they had been designed for it but I don't think they can currently. Any way... no ship would be able to launch all their missiles at the same time (or within 5s time frame)... not even close.

Steve have many times said that it is up to us if we want to abuse it... I'm fairly sure that he intended box launchers to mainly be used on ether small platforms or in at least limited fashion. He has at least hinted at that many times.

There really are no real defence against abusive box launched attacks using glass cannon fleets other than another similar fleet that fire just a bit further or with faster missiles... more or less.

[Potat999 (OP)]

Ahh... I had kind of assumed that box launchers sat above the armor layer and took damage first and thus would easily blow up the whole vessel with secondary explosions if they happened to take a hit, or at least would have the whole box rack blown off leaving the vessel toothless.  I guess that isn't the case?

[Zap0]

No, but that might be an interesting idea to balance them!

[Jorgen_CAB]

Ahh... I had kind of assumed that box launchers sat above the armor layer and took damage first and thus would easily blow up the whole vessel with secondary explosions if they happened to take a hit, or at least would have the whole box rack blown off leaving the vessel toothless.  I guess that isn't the case?

No... not directly... they will have a very high chance to blow up if hit though with a missile still in the tube (there is a specific technology that reduce the chance)... but armour still protects them. So I guess they are still built into the armour of the hull, there just are no internal mechanism to rearm them. Even if there would be a chance they took damage it would only be a slight issue. Most of the time a box launcher are likely to be empty before the ship is hit though unless you have had no possibility to shoot back before you are hit.

The issue with box launcher mass salvoes is that you don't need magazines so the space that otherwise goes to magazines and launchers can be entirely devoted to the launchers, this make box launched salvoes insanely large in comparison which render beam PD useless and even AMM usually are not up to the task most of the time. Just take a look at how many missiles you can cram into a FAC hull and then take about twenty of them and compare that to your regular cruiser at 20k and see how they compare, it is ridiculous almost.

If you have two squadrons of FAC with ten in each and each squadron have a leader with extra sensors... then each squadron pack about 135-180 size 4-6 launchers so each squadron can fire salvos at nearly 200 missiles and that is for 10k tonnage. There really are not much defenses that can realistically deal with that aside a 10k station dedicated to only AMM defenses. A standard 10k destroyer would stand no chance against such a threat, you probably would need 4-5 destroyers to have a decent chance to defend against that attack without horrendous losses.

[nuclearslurpee]

The problem is balance but in my opinion also reality... in real life there are rarely such a thing as 0 and 1 mechanics as this is. For example it is nearly impossible to make launchers of this type to expend all the ordnance at the same time... the more launchers on any one platform the less likely it is they can all be launched at the same time for many different reasons... be it physical or electronic reasons. It just are quite unrealistic that you ever could launch 50 missiles at the same time from the same smallish platform even under the best of circumstances with all the complications it would make even if we talk about sci-fi there will be limitations and that is the problem with the mechanic as it is unbalanced without them.

snip

The main issue with missile warfare is one of balance in relation to fire-controls and the salvo mechanics. If this was redesigned then box launchers could become a more reasonable weapons and you would only use box launchers on smaller platforms where they make more sense. Not even Harpoon launchers on naval warship can be considered a box launcher as they can be reloaded at sea. The mark 41 VLS could be reloaded at sea if they had been designed for it but I don't think they can currently. Any way... no ship would be able to launch all their missiles at the same time (or within 5s time frame)... not even close.

It seems like an interesting and reasonable "fix" would be to make fire controls (of both types, if we're being honest) have an upper limit to how many weapons they can control at once. A bit of a crude fix that certainly can't capture the detail of real naval missile combat but it would certainly have an effect. Ideally with a tonnage requirement that increases nonlinearly so that the overall cost per weapon of a BFC goes up as the number of weapons increases, but not so quickly at small numbers of weapons that the optimal becomes one FC per weapon.

There is already some precedent in the single-weapon BFCs Steve is adding for 1.13 so this is a rational extension I think.

This would allow box launcher fighters/FACs to remain viable but greatly reduce the efficiency of mounting dozens or hundreds of box launchers on a full-size warship hull significantly. However, there is one problem right now which is that MFCs are very, very cheap tonnage-wise at only 1/4 the cost of equivalent active sensors, so the actual tonnage impact may be quite minimal unless this is changed.

[Potat999 (OP)]

However, there is one problem right now which is that MFCs are very, very cheap tonnage-wise at only 1/4 the cost of equivalent active sensors, so the actual tonnage impact may be quite minimal unless this is changed.

Agreed on this.  I was a bit floored when I realized my box launcher spam platform for short range missiles could just mount 10 MFCs to make point defense that much more of a PITA.

I understand why a narrow beam sensor should have longer range/lower tonnage than a wide angle one from a lore perspective. 

Still, it seemed that a 5x5ton MFCs supporting 1000 tons of launcher was a bit skewed against the the 200-400T BFC supporting 1000T of PD weaponry.   In the normal launcher case magazine tonnage compensates for this but not so in the box case.

Just spitballing, but maybe if box launchers or large salvos for some reason were incentivized to use missiles with on board sensors that would lower the total effective payload of the salvo compared to traditional launchers.  Maybe ECM could cause loss of lock to a % of missiles instead of a flat hit chance malus, and also impact larger salvos (or smaller MFCs) more strongly?

I haven't really played the game much tho so I'm in no position to make balance judgements, lol.