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Is naval AA worth it or not, trying to do some math?

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Denkt

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I think this is an interesting question. Naval AA do two this, shoot down Aircrafts and reduce damage Aircrafts deal on your ship.

According to the wiki, only the ship attacked will have a chance to shoot against the Aircrafts (so AA cruisers is maybe not a good idea). Chance to hit is around 27% to 20% depending on the Aircraft's agility, higher agility reduce hit rate somewhat.

Only if a hit is rolled while a number of Aircrafts be shoot down, so about only 1/5 or 1/4 attacks will lead to Aircrafts being shoot down.

The number of Aircrafts shoot down is a % of the total attacking Aircrafts and that % is between 0 and AA value of the attacked ship. On a hit you can expect AA value/2 % Aircrafts shoot down

So Assuming 25% chance to hit, we can expect this % of Aircrafts shoot down for different AA values:
  • 10 AA = 1.25%
  • 20 AA = 2.5%
  • 30 AA = 3.75%
  • 40 AA = 5%
  • 50 AA = 6.75%
So even very high AA values, you can't expect to shoot down many Aircrafts, however keep in mind that shoot down Aircrafts wont get to attack the ship and thus deal damage

The second part is damage reduction, here 20% of each ship contribute to the damage reduction. Using the formula, we get the following damage reduction from AA value (how much fleet AA value need)
  • 10 (50) = 24%
  • 100 (500) = 38%
  • 200 (1000) = 43%
  • 300 (1500) = 47%
  • 400 (2000) = 49%
  • About 420 (2080) the cap of 50% damage reduction is reached
As you can see the damage reduction gain is huge with just a small investment in AA but sharply drops after that.

So the conclusion seems to be that AA is not Worth to focus on as the damage reduction, while nice on require a rather modest investment to gain half the reduction while the number of Aircrafts expect to be shoot down is really few and Aircrafts are quite cheap. A better investment is to invest the resources into being stuff that kills ships and use dual purpose guns to gain the damage reduction bonus.

If I got to make some Changes, I would probably remove the chance to hit and instead just focus on the second part which roll the amount of Aircrafts AA kills, it feels to binary and not realistic. Also I would also try to find a way for non attack ships to shoot down Aircrafts as of right now, stuff like AA crusiers don't make much sense as screens are seldom attack by Aircrafts.

Right now I feel these things are bit off:
  • Damage reduction is very favorable for a tooken investment in AA but unfavorable for massed AA
  • Only the attacked ship will actually shoot down aircrafts at a very low chance to even hit, most attacks will have no aircaft losses no matter the AA score of the ship
  • The specalized AA module is expensive as it increase total cost of the ship by 2% which may make it more expensive than the dual purpose gun, which is superior to it as it also provide light gun attacks while the extra AA from the AA module hardly seems to matter.
  • The quality of aircrafts don't matter if the AA land a hit, it will in such case shoot down as many 1944 aircrafts as 1936 aircrafts (but it will hit 1944 aircrafts somewhat less often).

US naval AA shoot down around 30% of the Aircrafts that entered its range or over 2k with about 1k destroyed by fighters, however even with a very extreme focus on AA you can't expect anywhere near those numbers. In one case a single US destroyer shoot down like 9 attacking Aircrafts if remember correctly and probably damage more, in game the destroyers wont do even shoot at the Aircrafts. The battleship South Dakota was credited for shooting down 26 Aircrafts in one battle (however this may be exaggerated).

If you worry about Aircrafts, the by far best way is to keep your navy out of range of naval bombers, and operate in areas in which you can provide air cover.
 
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It is like i excpected. AA on ships is not worth the cost.

What about land based AA?
 
"According to the wiki, only the ship attacked will have a chance to shoot against the Aircrafts"

If that's true then it's a big problem with the simulation. Also, the main reason American ship anti-air was so effective I think is because they developed proximity fuses for their shells which was basically a mini radar in every piece of ammunition. I read once that it increased anti-air effectiveness by 500%.
 
I had a fleet with a lot of AA, 4-6 cheap BC with 1 main gun and only AA and destroyers for screens. I just sent to help allies to Mediterranean sea, they end up destroying over thousands naval bomber by just sitting there. They were worth it by shooting down a lot of planes and if they got damaged little bit they would repair and go back.
 
Riekopo said:
"According to the wiki, only the ship attacked will have a chance to shoot against the Aircrafts"

If that's true then it's a big problem with the simulation. Also, the main reason American ship anti-air was so effective I think is because they developed proximity fuses for their shells which was basically a mini radar in every piece of ammunition. I read once that it increased anti-air effectiveness by 500%.
Click to expand...

Ahem, proximity fuses were British technology shared with the USA during the Tizard Mission ;)
 
Denkt said:
Right now I feel these things are bit off:
  • Damage reduction is very favorable for a tooken investment in AA but unfavorable for massed AA
  • Only the attacked ship will actually shoot down aircrafts at a very low chance to even hit, most attacks will have no aircaft losses no matter the AA score of the ship
  • The specalized AA module is expensive as it increase total cost of the ship by 2% which may make it more expensive than the dual purpose gun, which is superior to it as it also provide light gun attacks while the extra AA from the AA module hardly seems to matter.
  • The quality of aircrafts don't matter if the AA land a hit, it will in such case shoot down as many 1944 aircrafts as 1936 aircrafts (but it will hit 1944 aircrafts somewhat less often).
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1. It is the same philosophy like land AA. You need a minimum AA to prevent un-regular air attack damage. If you don't have AA, the planes will fly very low and very accurate.
2. The ship AA is mostly for prevent damage, not killing planes.
3. Ship is supposed to have both AA module and dual purpose gun. The AA modules do have % increase for all other AA in the ship (magically)

There is unconfirmed hint that if you have air superiority then enemy planes loss will increase but the first thing is to avoid enemy land planes.
 
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The main problem is that only 1 ship gets the full damage output of one air wing wich attacks. 2 attacking air wings can attack 2 ships, but those 2 wings can attack the same ship too. The damage should be spread around the fleet. IF that would work i would be ok if only 1 of 5 ships shot back and kill some planes, but as of now it can be that your fleet gets attacked and your ships will only shoot back 1 out of 5 times or maybe less if your are unlucky. Could be 1 out of 10 times, but your fleet will not survive 9days to damage planes at the 10th day. Planes are an invincible force wich come every day and damage your ships and you cant nothing do except to hope, even if you build ships full of AA to prevent massiv losses they get sunk like 1 ship per day. How you want to prevent any damage? The planes will just come the next day again with only cost of fuel. Fleet AA should always kill at least 1 plane and the air wings get some damage too. That could be simulated by fatigue of planes but we all know that is not balanced. :-(

Dont test yourself with 36 planes, please test 40planes against 40ship AA and you will see the Problem.

For land AA there are Techs wich increase the hit chance by 20% per radar tech. I think they just forgot the same thing for naval AA. Naval AA gets worse as the war goes on, but it should be get better with evey year.

If we could solve that problem we can fix anonther ai problem. Every 1-3 weeks i see on this forum many complain about how easy it is to kill the AI fleets with just some naval bombers and be afk. After some ingame weeks the fleets are sunk.

Make naval AA great again!
 
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Diwtop said:
For land AA there are Techs wich increase the hit chance by 20% per radar tech. I think they just forgot the same thing for naval AA. Naval AA gets worse as the war goes on, but it should be get better with evey year.
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Naval AA increases extrem each 4 years (value: 1.5, 2, 3, 5; multiplyer:0.1,0.1,0.125,0.15) and you get more slots on ships. I don't see your point?

Now one might try to tweak the formula, but I think the max of 0.5 reduction is hardcoded.
 
Taghmon said:
Naval AA increases extrem each 4 years (value: 1.5, 2, 3, 5; multiplyer:0.1,0.1,0.125,0.15) and you get more slots on ships. I don't see your point?

Now one might try to tweak the formula, but I think the max of 0.5 reduction is hardcoded.
Click to expand...

Yes the value of AA increase every 4 years and the planes get far more agiliy each 4 years. To say it easy, the formular for a hit chance is navalAA vs agility. Thats why navalAA gets worse every 4 years. Maybe @bitmode could make an enlightenment here. Iam not a native english speaker. :)

Yes reduction is hardcoded, but i dont understand why an inxrease of reduction will help. The air wing will attack every day. Its not like they attack you one day and now there are 4 weeks peace in the theater.


kettyo said:
Would you write a suggestion about this?
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i dont know, do paradax read the suggestion forum?
 
The agility thing is actually very noticible, but it's all part of the arms race. I refitted one of my strike forces with T3 AA and DP secondaries in '41 during one game, and was swatting 20-30 bombers out of 150 attackers for around 5-6 months then the AI decided not to attack, 2 years later the Japanese managed to sink two of my capitals from the upgraded fleet and many attacks went without a single bomber being shot down in response.

I think it does need some re-balancing as that seemed a little wrong but back then AA on ships was good but not great, it's not like today where it would be suicidal for a group of bombers to try and attack a type 45 Destroyer.
 
So I ran an experiment to see if I could win the air war from the sea. As Germany, I built a small but current surface navy, and I upgraded and kept upgraded AA, firing radar, and multipurpose guns. I also hired the naval AA admiral.

After having parked myself in the channel for about 6-9 months, I had shot down almost 2,000 British CAS / bombers with the loss of 1 destroyer. I’d say it’s pretty effective.

I did the same thing as the US and after parking my fleet in in the marianas the Japanese Air Force impaled itself on my I AA guns and was never really the same after.

Naval AA is definitely expensive, and definitely works. Whether it’s worth it or not depends on whether you need a fleet that can survive enemy air attack. Operation sea lion certainly goes a lot better when your ships have AA. So does any pacific campaign.
 
Diwtop said:
Yes the value of AA increase every 4 years and the planes get far more agiliy each 4 years. To say it easy, the formular for a hit chance is navalAA vs agility. Thats why navalAA gets worse every 4 years. Maybe @bitmode could make an enlightenment here. Iam not a native english speaker. :)
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The agility of naval bombers does not grow as fast as ship AA can (+33% versus doubling or tripling). On the other hand naval bomber targeting and attack increase considerably, so both sides should take more losses late game. I don't have MtG, so I have not thought much about how far this balance can be pushed one way or another. OP seems to be on the right track though.
 
smackamack said:
After having parked myself in the channel for about 6-9 months, I had shot down almost 2,000 British CAS / bombers with the loss of 1 destroyer. I’d say it’s pretty effective.

I did the same thing as the US and after parking my fleet in in the marianas the Japanese Air Force impaled itself on my I AA guns and was never really the same after.
Click to expand...

This is great news!
 
I did 10 test, using a "Flak Platform" which is just a superheavy ship with as much AA as possible, reaching a value of 86.2 AA and parked it in the English channel.
Flak Platform.jpg

I gave UK 1k 1944 naval bombers and set them to hunt ships in the english channel and made war with germany, ai was turned of.

Now you may expect that the aircrafts would take some losses, but only in 1 test out of 10 was aircrafts actually shoot down and in that test 20 aircafts was shoot down. The super heavy ship was sink in 1 or 2 air attack in every test, if not sunk in the first air attack it would lose about 95% of its HP. So on average this ship managed to shoot down 2 aircrafts before being sunk.

I think that is too favorable for the Aircrafts or rather with such extreme focus on AA should not more Aircrafts be lost? And consider that not the whole fleet get to use its AA to shoot down Aircrafts, it was calculated that about 60% of the Aircrafts shoot down by US navy was not shoot down by the target.

smackamack said:
So I ran an experiment to see if I could win the air war from the sea. As Germany, I built a small but current surface navy, and I upgraded and kept upgraded AA, firing radar, and multipurpose guns. I also hired the naval AA admiral.

After having parked myself in the channel for about 6-9 months, I had shot down almost 2,000 British CAS / bombers with the loss of 1 destroyer. I’d say it’s pretty effective.

I did the same thing as the US and after parking my fleet in in the marianas the Japanese Air Force impaled itself on my I AA guns and was never really the same after.

Naval AA is definitely expensive, and definitely works. Whether it’s worth it or not depends on whether you need a fleet that can survive enemy air attack. Operation sea lion certainly goes a lot better when your ships have AA. So does any pacific campaign.
Click to expand...
It must be quite bad Aircrafts given that 1944 naval bombers can pretty much one-shoot any ship.​
 
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The gap between naval bomber technology is huge:
  • 1936: 7.5 naval targeting and 15 naval attack = 7.5*15 = 112.5 anti naval score
  • 1940: 10 naval targeting and 20 naval attack = 10*20 = 200 anti naval score (+78% more effective than 1936)
  • 1940: 12.5 naval targeting and 25 naval attack = 12.5*25 = 312.5 anti naval score (+56% more effective than 1940)
Also since only a certain amount of Aircrafts get to attack the ship, quality of the Aircrafts matter alot.
 
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