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Aerial Combat refers to one of the stages conducted during combat in the game, conducted after detection and before Support Expedition, Opening Torpedo Salvo (if condition for them to happen are fulfilled), and display of the engagement form.

In Aerial Battle nodes, after finishing Aerial Combat rundown for the first time, the engagement form will be displayed a second process of Aerial Combat will occur, with the potential exception of the contact phase.

In Night Battle nodes, Aerial Combat usually does not occur. In some rare cases when Night Battle nodes can conditionally be turned into Day Battle, the Aerial Combat phase will start immediately without a detection phase.

If Jet plane(s) is(/are) carried by carrier(s), then an additional jet assault would occur before the regular opening air strike phase.

For the mechanism applied on aircrafts in support expedition, land-based aerial support, shelling phase and anti-submarine operations, please refer to respective pages for further information.

Note that, unless otherwise specified, all the numerical values on this page are only applicable to the player's side.

Aerial Combat Stages

Stage Notes
Stage 1 Fighter Combat Battle for air supremacy. Determines if Artillery Spotting and/or Contact are possible. Both fighters and bombers are shot down in this phase.
Contact Successful Contact would increase Opening Air Strike damage.
Stage 2 Fleet Anti-air Defense Fleet defends against enemy bombers, shooting down a number of enemy bombers
Anti-air Cut-in An anti-aircraft fire director-guided attack may cause damage to all enemy bombers
Stage 3 Bombing Each bomber squad attacks one random target. See Damage Calculation for details

Stage 1

Fighter Combat

$ F_{Power} = \sum^\text{All Slots} \left \lfloor \sqrt{N_{slot}} \left ( A_{p} + \bigstar_{p} \right ) + P_{p} \right \rfloor $ [Example 1]


  • $ F_{Power} $ is the total Fighter Power of the fleet.
  • $ N_{slot} $ is the current plane count (slot size) of that slot.
  • $ A_{p} $ is the plane's displayed AA stat.
  • $ \bigstar_{p} $ is the plane's improvement bonus to the AA stat.
    • $ \bigstar_{p} = \bigstar \cdot 0.2 $ for fighters, $ \bigstar_{p} = \bigstar \cdot 0.25 $ for (fighter-)bombers
  • $ P_{p} $ is the plane's Aircraft Proficiency bonus.


  • GreenPlaneSeaplane Fighter Icon Fighter planes and Jet-powered Fighter-Bomber Icon 1BluePlaneRedPlaneSeaplane Jet/Torpedo / Dive / Seaplane bombers participate in the Fighter Combat.
    • Depending on the air state achieved, all the above planes will be subjected to plane loss, regardless if they had or didn't have an AA stat.
  • Recon planes (carrier basedYellowPlane or seaplane reconSeaplane) will NOT participate in Fighter Combat.
    • Recon planes are unaffected by the results of Air State and suffer no plane loss from this stage.
  • Aircraft Proficiency is factored into Fighter Power on top of the above formula. The exact formula is under investigation.
  • The allied fleet and enemy fleet's Fighter Powers are compared to determine the result of Fighter Combat:
Fighter Power Result Text Display  % Enemy Planes Shot Down (Approx.)  % Allied Planes Shot Down (Approx.) Contact Combat Screens
FP ≥ 3*EFP Air Supremacy
Seikuuken Kakuho!
0~100% 2.5~5.83% Allied only Combat supremacy
3*EFP > FP ≥ 1.5*EFP Air Superiority
Koukuu Yuusei!
0~70% 7.5~17.5% Both sides Combat superiority
1.5*EFP > FP > 2/3*EFP Air Parity No text displayed 0~50% 12.5~29.1% Neither side Combat parity and incapability
2/3*EFP ≥ FP > 1/3*EFP Air Denial No text displayed 0~30% 17.5~40.8% Both sides Combat parity and incapability
FP ≤ 1/3*EFP

Air Incapability

Seikuuken Soushitsu!
0~10% 25~58.3% Enemy only Combat denial

Note: For the users who are aware of the terminology switch between AD and AI, this was caused by a mistranslation. The correct order is AD > AI.

  • EFP: Enemy Fighter Power, FP: Fighter Power. Abbreviated to save space.
  • If both sides launch no planes, then the air state is considered Air Parity.
    • If any planes were launched during the aerial phase, but the fighter power of both sides are zero (Eg. Enemy only launched bombers with 0 AA Stat), the allied fleet will be awarded Air Supremacy. (Due to meeting the AS+ requirement of 0*3=0)
  • Carriers will participate in Aerial Phase regardless of their damage state, provided they have planes.
  • Night Contact can be triggered under the same air states as normal Day Contact, with the exception of PvP Battles, or when the battle starts at Night.

The formula for allied plane loss (On a per-slot basis) is as follows:

$ \text{Plane Loss} = \big \lfloor S * 0.1 * ( \text{random} \in \left [ 0 , \left ( A / 3 * 100 \right ) \right ] / 100 + \left ( A / 4 \right ) ) \big \rfloor $


  • $ S $ is the plane's slot size.
  • $ A $ is the Air State modifier, where:
    • $ A = \begin{cases} 1, & \text{ for Air Supremacy} \\ 3, & \text{ for Air Superiority } \\ 5, & \text{ for Air Parity } \\ 7, & \text{ for Air Denial } \\ 10, & \text{ for Air Incapability } \end{cases} $
  • Random function takes an random integer within $ 0 $ and $ \left ( A / 3 * 100 \right ) $ in a linear distribution.

The formula for enemy plane loss (On a per-slot basis) is as follows:

$ \text{Plane Loss} = \big \lfloor S * \left ( 0.035 * \text{random} \in \left [ 0 , A \right ] + 0.065 * \text{random} \in \left [ 0 , A \right ] \right ) \big \rfloor $


  • $ S $ is the enemy plane's slot size.
  • $ A $ is the Player's Air State modifier, where:
    • $ A = \begin{cases} 10, & \text{ for Air Supremacy} \\ 7, & \text{ for Air Superiority } \\ 5, & \text{ for Air Parity } \\ 3, & \text{ for Air Denial } \\ 1, & \text{ for Air Incapability } \end{cases} $
  • Random function takes an random integer within $ 0 $ and $ A $ in a linear distribution.


Combat contact
Contact takes place during the Aerial Combat phase. It increases bombing damage for all allied bombers. When successful, an image of the squadron performing contact is shown in the opposing fleet's formation indicator, with the text "触接中".
  • Trigger conditions:
    • Air Denial, Air Superiority, or Air Supremacy (i.e. not Air Incapability or Air Parity)
    • At least one carrier scout plane, seaplane scout, or torpedo bomber equipped.
    • Trigger rate depends on the number, slot size, and types of planes equipped, detailed below.

Contact Trigger Chance

The process that determines whether or not Contact triggers consists of two parts.[1]

Phase 1: Contact Trigger

In this stage, the system merely determines whether Contact triggers at all.

Which plane triggers it has not been determined yet.

Each plane has its own "trigger rate", which according to current research is based on the plane's LoS and the size of the slot it's in. The trigger rates of all planes in your fleet are then added together to determine the chance of successful Contact. A provisional approximation formula is given by:

$ P_{\text{Contact}} = \sum^{\text{All Slots}} \left ( \sqrt{N} \cdot E_{l} \cdot E_{m} \cdot C \right ) $


  • $ P_{\text{Contact}} $ is the overall chance of successful Contact
  • $ N $ is the current plane count (slot size) of that slot
  • $ E_{l} $ is the plane's displayed LoS stat
  • $ E_{m} $ is the plane type modifier.
    • For Carrier-based Reconnaissance and Reconnaissance Seaplanes, $ E_{m} = 0.04 $
    • For Torpedo Bombers, the value would be much smaller.
  • $ C $ is the Air Control Status.
    • For Air Supremacy (AS+), $ C = 1 $
    • For Air Superiority (AS), $ C = 0.6 $

If Contact is determined to be successful, the system proceeds to Stage 2. If Contact fails, nothing else happens.

Phase 2: Contact Plane Selection

Now that Phase 1 has been successful the system has to determine which plane is going to trigger Contact. The priority among planes is as follows:

  • Higher Accuracy stats mean higher priority
  • If two or more planes have the same amount of Accuracy, the selection process goes through them from top to bottom, start from the first ship first slot then first ship second slot and end with the sixth ship last slot.

The system goes through each plane from top to bottom priority until either one is selected or none is. Current data suggests that a plane's selection rate is determined by its LoS stat and that improvements seems to increase the chances as well[2]. Another provisional approximation formula is given by:

$ P_{\text{Select}} = E_{l} \cdot C $


  • $ P_{\text{Select}} $ is the selection rate of a given plane
  • $ E_{l} $ is the plane's displayed LoS value
  • $ C $ is the Air Control Status.
    • For Air Supremacy (AS+), $ C = 0.07 $
    • For Air Superiority (AS), $ C = 0.06 $
    • For Air Denial (AD), $ C = 0.055 $

If no plane is selected in the end, then Contact is cancelled and doesn't trigger.

Contact Damage Modifier

  • The damage increase depends on the +accuracy bonus Icon Hit of the squadron performing contact.
Example Planes
+0 112% Ryuusei Kai
+1 112% Type 0 Reconnaissance Seaplane, Ryuusei (601 Air Group), Type 2 Large Flying Boat
+2 117% Type 0 Observation Seaplane, Saiun, PBY-5A Catalina, Prototype Keiun
+3 or more 120% Type 2 Reconnaissance Aircraft, Tenzan Model 12 (Tomonaga Squadron), Type 97 Torpedo Bomber (Tomonaga Squadron)


  • YellowPlaneType 2 Recon Aircraft is useful in the case that the bombing damage bonus is desired while not removing the chance for T-disadvantage, due to its high trigger rate.
  • With contact, the maximum attack power of bombing (before defense, critical and ammo) is around 180. With some luck, it's possible to sink even Ru-class Flagships (Armor = 99) in one strike without a critical.
  • Contact only triggers during AD, AS or AS+. This means that it does not work during AI or AP.

Stage 2

Fleet Anti-air Defense

The Fleet Anti-air Defense system was updated on 14 November 2014, alongside the addition of the Anti-air Cut-in system. It was then patched on 26 June 2015 to fix several bugs.

System Mechanics

  • Each enemy bomber slot is assigned at random to a defending ship.
  • Those ships then, for each assigned enemy slot, have two approximately 50% concurrent but independent chances to shoot down enemy planes.
    • The first chance (termed Proportional Air Defense) can shoot down a number proportional to the initial size of the enemy bomber squadron after anti-bomber combat.
    • The second chance (termed Fixed Air Defense) can shoot down a fixed number of enemy bombers determined by stats and equipment only.
    • Simply speaking, There's a 25% chance you can trigger both Proportional and Fixed Air Defense, 25% only trigger Proportional, 25% only Fixed, and 25% none of them being triggered, for every slot.
  • Finally, one bomber from each enemy squadron will always be shot down regardless of success or failure of the previous two chances for friendly ships on abyssal. If AACI was committed, then it would also shoot down a specific amount of planes per slot according to the AACI's API type.

The numbers of planes shot down are given by the equations below:

$ S_{\text{Proportional}} = \left \lfloor \frac{ f ( \hat{A} ) \cdot C }{400} \cdot N \right \rfloor $

$ S_{\text{Fixed}} = \left \lfloor \frac{ \big ( f ( \hat{A} ) + \lfloor \hat{F} \rfloor \big ) \cdot K C }{10} \right \rfloor $


  • $ S_{\text{Proportional}} $ is the number of planes shot down by Proportional Air Defense
  • $ S_{\text{Fixed}} $ is the number of planes shot down by Fixed Air Defense
  • $ \hat{A} = A_{base} + \sum^{\text{All Slots}} \bigg ( \left ( E_{mod} \cdot E_{aa} \right ) + \left ( E_{\bigstar} \cdot \sqrt{\bigstar} \right ) \bigg ) $
    • $ \hat{A} $ is the adjusted AA value of the ship, following the formula above.
    • $ A_{base} $ is the basic AA value of the ship; that is, its numeric AA value without factoring equipment.
    • $ E_{mod} $ is the equipment type modifier (see: Equipment Modifiers).
    • $ E_{aa} $ is the equipment's displayed AA stat.
    • $ E_{\bigstar} $ is the equipment's improvement modifier to adjusted AA.
      • High-Angle Mounts: 3
      • Air Radars: 0
      • Anti-Air Guns: 4
  • $ N $ is the current plane count (slot size) of the targeted slot.
  • $ \hat{F} = 1.54 \cdot \left \lfloor F \cdot \sum^\text{All Ships} \bigg \lfloor \sum^{\text{All Slots}} \left ( \left ( E_{fmod} \cdot E_{aa} \right ) + \left ( E_{f\bigstar} \cdot \sqrt{\bigstar} \right ) \right ) \bigg \rfloor \right \rfloor $
    • $ \hat{F} $ is the adjusted AA value of the fleet, following the formula above. This is only added to the adjusted AA value for Fixed Air Defense, as a bonus.
    • $ F $ is the formation modifier. (see: Formation Modifiers)
    • $ E_{fmod} $ is the equipment type multiplier for fleet AA (see: Equipment Modifiers), not to be confused with the regular equipment type modifier.
    • $ E_{f\bigstar} $ is the equipment's improvement modifier to fleet AA.
      • High-Angle Mounts: 3
      • Air Radars: 1.5
      • Anti-Air Guns: 0
  • $ f( x ) = q \cdot \left \lfloor \frac{x}{q} \right \rfloor $
    • If the ship is not equipped with anything, $ q = 1 $
    • If the ship is equipped with something, $ q = 2 $
  • $ \left \lfloor x \right \rfloor $ is the floor function; that is, the rounding down of input $ x $
  • $ K $ is the Anti Air Cut-In multiplier to Fixed Air Defense, default 1 if no AACI is triggered. This is a modifier independent of the flat shootdown caused by AACI, and depends on the API identity of the triggered AACI. When AACI is triggered, this multiplier is applied individually for each ship in the fleet, not only the ship performing AACI. See the Anti Air Cut In table in the respective section for a list of K-values corresponding to different AACI API numbers.
  • $ C $ is the Combined Fleet modifier. Defaults to 1 if the fleet is not combined.
    • Main Fleet: 0.72
    • Escort Fleet: 0.48

To see this formula in use, click below.

Anti-Air Defense Formula Example

Example on how to use the Fleet Anti-air Defense formula to calculate the number of planes shot down by Fixed and Proportional Air Defense.

This example is for a fleet consisting of Maya Kai Ni, with 90mm Single High-angle Gun Mount +4 / 90mm Single High-angle Gun Mount +4 / Bofors 40mm Quadruple Autocannon Mount / Type 21 Air Radar Kai.

To begin, we start by calculating the adjusted AA value for Maya.

$ \begin{align} \hat{A} & = A_{\text{Maya K2}} + \left (E_{\text{Modifier}} \cdot E_{\text{90mm}} + E_{\bigstar} \cdot \sqrt{\bigstar} \right ) + \left (E_{\text{Modifier}} \cdot E_{\text{90mm}} + E_{\bigstar} \cdot \sqrt{\bigstar} \right ) + \left (E_{\text{Modifier}} \cdot E_{\text{Bofors}} + E_{\bigstar} \cdot \sqrt{\bigstar} \right ) + \left (E_{\text{Modifier}} \cdot E_{\text{T21K}} + E_{\bigstar} \cdot \sqrt{\bigstar} \right ) \\ & = 106 + (4 \cdot 8 + 3 \cdot \sqrt{4}) + (4 \cdot 8 + 3 \cdot \sqrt{4}) + (6 \cdot 10 + 0 \cdot \sqrt{0}) + (3 \cdot 5 + 0 \cdot \sqrt{0}) \\ & = 106 + 38 + 38 + 60 + 15 \\ & = 257 \end{align} $

Afterwards, we can pass this value into the step function $ f(x) $, which rounds down the adjusted AA value in steps of 2 when a ship has equips.

$ f(\hat{A}) = f(257) = 256 $

Then, we calculate the adjusted AA value for the fleet, which in this example only includes Maya Kai Ni herself.

$ \begin{align} \hat{F} & = 1.54 \cdot \left \lfloor F_{\text{Line Ahead}} \cdot \left \lfloor (E_{\text{Multiplier}} \cdot E_{\text{90mm}} + E_{f\bigstar} \cdot \sqrt{\bigstar}) + ( E_{\text{Multiplier}} \cdot E_{\text{90mm}} + E_{f\bigstar} \cdot \sqrt{\bigstar} ) + (E _{\text{Multiplier}} \cdot E_{\text{Bofors}} + E_{f\bigstar} \cdot \sqrt{\bigstar} ) + ( E_{\text{Multiplier}} \cdot E_{\text{T21K}} + E_{f\bigstar} \cdot \sqrt{\bigstar} ) \right \rfloor \right \rfloor \\ & = 1.54 \cdot \left \lfloor 1.0 \cdot \lfloor ( 0.35 \cdot 8 + 3 \cdot \sqrt{4} ) + ( 0.35 \cdot 8 + 3 \cdot \sqrt{4} ) + ( 0.2 \cdot 10 + 0 \cdot \sqrt{0} ) + ( 0.4 \cdot 5 + 1.5 \cdot \sqrt{0} ) \rfloor \right \rfloor \\ & = 1.54 \cdot \left \lfloor 8.8 + 8.8 + 2 +2 \right \rfloor \\ & = 1.54 \cdot 21 \\ & = 32.34 \end{align} $

Using these two values, we can calculate the number of planes shot down by Proportional Air Defense:

$ \begin{align} S_{\text{Proportional}} & = \left \lfloor \frac{ f ( \hat{A} ) }{400} \cdot N \right \rfloor \\ & = \left \lfloor \frac{256}{400} \cdot N \right \rfloor \\ & = \left \lfloor 0.64 \cdot N \right \rfloor \end{align} $

And the number of planes shot down by Fixed Air Defense, assuming AACI activates, with a multiplier K = 1.65

$ \begin{align} S_{\text{Fixed}} & = \left \lfloor \frac{ ( f ( \hat{A} ) + \lfloor \hat{F} \rfloor ) \cdot K }{10} \right \rfloor \\ & = \left \lfloor \frac{ ( 256 + \lfloor 32.34 \rfloor ) \cdot 1.65 }{10} \right \rfloor \\ & = \left \lfloor \frac{288 \cdot 1.65}{10} \right \rfloor \\ & = 47 \end{align} $

From these two numbers, we can conclude that Maya Kai Ni with the previously mentioned setup will shoot down 64% of an enemy plane slot with Proportional Air Defense, and/or 47 planes from Fixed Air Defense. We can add this number to the AACI shootdown and the single plane always shot down, to get a final value of 56 planes shot down, if both AACI and Fixed Air Defense triggers.

Abyssal Anti Air Formula


$ S_{\text{Proportional}} = \left \lfloor \frac{ \lfloor \hat{A} \rfloor }{400} \cdot N \right \rfloor $

$ S_{\text{Fixed}} = \left \lfloor \frac{ \lfloor \hat{A} + \hat{F} \rfloor }{10.6} \right \rfloor $


  • $ \hat{A} = \bigg (2 \cdot \sqrt{A_{base}} + \sum^{\text{All Slots}} \left ( E_{mod} \cdot E_{aa} \right ) \bigg ) \cdot R $
  • $ \hat{F} = 2 \cdot \left \lfloor F \cdot \sum^\text{All Abyssals} \bigg \lfloor \sum^{\text{All Slots}} \left ( E_{fmod} \cdot E_{aa} \right ) \bigg \rfloor \right \rfloor \cdot \hat{R} $
  • $ R $ is the Ship AA Resistance of the plane the ship is defending against. (See Plane AA Resist Modifiers)
  • $ \hat{R} $ is the Fleet AA Resistance of the plane the ship is defending against.

Formation Modifiers

Formation Modifier
Line Ahead, Line Abreast, Echelon 1.0
Double Line 1.2
Diamond 1.6
Combined Fleet
Cruising Formation 1 1.1
Cruising Formation 2 1.0
Cruising Formation 3 1.5
Cruising Formation 4 1.0

Equipment Modifiers

Equipment Type Ship AA Modifier Fleet AA Modifier
High-angle Mounts, Anti-aircraft Fire Directors 4 0.35
Machine Guns & Rocket Launchers 6 0.2
AA Radars 3 0.4
Main Gun, Seaplanes 0 0.2
Type 3 Shell 0 0.6
Other Abyssal AA Equipment, including CIC, High-angle Single-Mount 0 0.2
  • There may be other types of equipment with modifiers that affect the air defense equations which are not yet known.

Plane AA Resist Modifiers

BluePlane Torpedo Bombers
Plane Type Ship AA Modifier Fleet AA Modifier
Type 97 Torpedo Bomber (Murata Squadron)Type 97 Torpedo Bomber (Murata Squadron) 143 Card 0.6 1
Tenzan Model 12 (Murata Squadron)Tenzan Model 12 (Murata Squadron) 144 Card 0.6 1
Type 97 Torpedo Bomber (Tomonaga Squadron)Type 97 Torpedo Bomber (Tomonaga Squadron) 093 Card 0.6 1
Tenzan Model 12 (Tomonaga Squadron)Tenzan Model 12 (Tomonaga Squadron) 094 Card 0.6 1
RedPlane Dive Bombers
Plane Type Ship AA Modifier Fleet AA Modifier
Type 99 Dive Bomber (Egusa Squadron)Type 99 Dive Bomber (Egusa Squadron) 099 Card 0.6 1
Suisei (Egusa Squadron)Suisei (Egusa Squadron) 100 Card 0.6 0.7
Zero Fighter Model 62 (Fighter-bomber / Iwai Squadron)Zero Fighter Model 62 (Fighter-bomber Iwai Squadron) 154 Card 0.6 0.7
Seaplane Seaplane Bombers
Plane Type Ship AA Modifier Fleet AA Modifier
Zuiun (634 Air Group)Zuiun (634 Air Group) 079 Card 0.6 1
Zuiun Model 12Zuiun Model 12 080 Card 0.6 1
Zuiun Model 12 (634 Air Group)Zuiun Model 12 (634 Air Group) 081 Card ?? ??
Zuiun (634 Air Group/Skilled)Zuiun (634 Air Group Skilled) 237 Card 0.6 0.7
Zuiun Kai Ni (634 Air Group)Zuiun Kai Ni (634 Air Group) 322 Card 0.5 0.7
Zuiun Kai Ni (634 Air Group/Skilled)Zuiun Kai Ni (634 Air Group Skilled) 323 Card ?? ??
Jet-powered Fighter-Bomber Icon 1 Jet-powered Fighter-Bomber Icon 2 Jets
Plane Type Ship AA Modifier Fleet AA Modifier
Jet Keiun KaiJet Keiun Kai 199 Card 0.5 0.7
Kikka KaiKikka Kai 200 Card 0.5 0.5
Land-based Attack Aircraft Icon Land-based Attack Aircraft
Plane Type Ship AA Modifier Fleet AA Modifier
Type 1 Land-based Attack Aircraft (Nonaka Squadron)Type 1 Land-based Attack Aircraft (Nonaka Squadron) 170 Card 0.6 1


  • The ship selected to defend is not necessarily the target of the bomber. Any allied ship, including submarines, may be chosen to defend against bombers.
  • The forward sliding and machine gun animations seem to have no correlation with the calculations.
  • As per formula above, abyssal fleets use a different anti-air formula (and is believed to be weaker than player's anti-air in most of the cases).

Anti-Air Cut-In

This section mainly describe the effect of Anti-Air Cut-In. For perspective on how to setup Anti-Air Cut-In, Please read the Anti-Air Cut-In tab in Combat#Combat_Equipment_Setup section of the page.
Bandicam 2014-11-20 02-55-57-126.avi snapshot 00.26 -2014.11.20 03.09.34-

An Anti-Air Cut-In

Certain equipment combinations (see below) will provide a chance for an Anti-Air Cut-In (AACI) during the Aerial Combat Phase. When activated, the cut-in animation (shown on the right) appears before engaging the enemy fighters. However, the effect of an Anti-Air Cut-In does not affect the resulting air control state (AS+, AS, Air Parity or Denial), and calculation-wise, it only takes effect after fighters engage bombers in air combat. With an AA Cut-In and a good anti-air composition, it is sometimes possible to obliterate all incoming bombers before they inflict any damage, and even prevent enemy carriers from attacking during the shelling phase (due to having 0 bombers left).

Although several ships can be equipped with an AACI setup in one fleet, only one ship can perform an AACI during the aerial phase. The number of planes shot down is dependent on the ship performing the AACI and their equipment. Bringing more AACI capable ships will NOT increase the number of planes shot down via AACI.

Akizuki-class destroyers and Maya Kai-2 have a hidden bonus to certain AA Cut-in setups which increases the effectiveness tremendously.

In PVP Exercises, opposing fleets can do AACI, but the animation is not shown.

As of the 17th November 2017 update and Fall 2017 event, Abyssals are now able to AACI as long as they follow the proper equipment setup, but the animation is not shown. Known instances are Air Defense Princess and Artillery Imp III.

Trigger chance of AACI is solely determined by the API type. Fleet AA does not affect trigger chances[4]. Luck does not affect AACI trigger rate[5].

Be noted that AACI effects are added on to the regular anti-air fire of your fleet, thus anti-air stat of other ships or/and equipment on those ships in your fleet would still matter even if an AACI has been activated.

Equipment, API

The following table summarizes current known information about the various AACI types.[6][7][8][9]

API value Type Shot down per slot K value Proc Rate User Note
None - +1 1.0 N/A Player's fleet only Triggers if no other AACI is activated
+8 1.7[† 1] 65% Akizuki-ClassAkizuki Kai Banner
Teruzuki Kai Banner
Hatsuzuki Kai Banner
Suzutsuki Kai Banner
HA mount x2 + Radar
2 HR
+7 1.7 58% HA mount + Radar
3 HH
+5 1.6 50% HA mount x2
RedGunHeavyGreenAmmoAafd cRadar
+7 1.5 52% Battleships Large Main Gun + Sanshiki + AAFD + Air Radar
Customized HA plus AAFD iconCustomized HA plus AAFD iconRadar
+5 1.5[† 2] 55% All Built-in HA mount x2 + Air Radar
RedGunHeavyGreenAmmoAafd c
+5 1.45[† 3] 40% Battleships Large Main Gun + Sanshiki + AAFD
GreenGunDPAafd cRadar
+4 1.35 45% All HA mount + AAFD + Air Radar
8 BR
Customized HA plus AAFD iconRadar
+5 1.4[† 4] 50% Built-in HA mount + Air Radar
9 HA
GreenGunDPAafd c
+3 1.3 40% HA mount + AAFD
10 HCR
+9 1.65 60% Maya Kai NiMaya Kai Ni Banner HA + CDMG + Air Radar
11 HC
+7 1.5 55% HA + CDMG
12 CGR
+4 1.25 45% All CDMG + AA Gun + Air Radar
13 cannot be activated

[† 5]

14 HGR
+5[10] 1.45 Isuzu Kai NiIsuzu Kai Ni Banner HA + AA Gun + Air Radar
15 HG
+4 1.3 HA + AA Gun
16 HGR
+5 1.4 Kasumi Kai Ni BKasumi Kai Ni B Banner HA + AA Gun + Air Radar
17 HG
+3 1.25 HA + AA Gun
18 C
+3 1.2 Satsuki Kai NiSatsuki Kai Ni Banner CDMG
19 HC
+6 1.45 Kinu Kai NiKinu Kai Ni Banner HA + CDMG
(Cannot be Built-in HA)
20 C
+4 1.25 CDMG
21 HR
+6 1.45 Yura Kai NiYura Kai Ni Banner HA + Air Radar
22 C
+3 1.2 Fumizuki Kai NiFumizuki Kai Ni Banner CDMG
23 G
+2 1.05 UIT-25UIT-25 Banner or
I-504I-504 Banner
AA Gun (Cannot be CDMG)
24 HG
+4 1.25 Tatsuta Kai NiTatsuta Kai Ni Banner HA + AA Gun (Cannot be CDMG)
25 GRS
+8 1.55 Ise-class Kai/Kai NiIse Kai Ni Banner
Hyuuga Kai Ni Banner
Rocket Launcher K2 + Air Radar + Sanshiki 
26 HR
+7 1.4 Musashi Kai NiMusashi Kai Ni Banner 10cm Twin HA Mount Kai + Air Radar
27 Unknown
28 GR
+5 1.4 Ise-class Kai/Kai NiIse Kai Ni Banner
Hyuuga Kai Ni Banner
Musashi Kai NiMusashi Kai Ni Banner
Rocket Launcher K2 + Air Radar 
29 HR
+6 1.55 Hamakaze B KaiHamakaze B Kai Banner &
Isokaze B KaiIsokaze B Kai Banner
HA + Air Radar
Using Akiguns has a high chance to proc AACI 5/8 instead.
30 HHH
+4 1.3 Tenryuu Kai NiTenryuu Kai Ni Banner &
Gotland KaiGotland Kai Banner
HA + HA + HA
31 HH
+3 1.2 HA + HA
+4 1.2 HMS Royal Navy ShipsNelson Kai Banner
Warspite Kai Banner
Ark Royal Kai Banner
Jervis Kai Banner
Janus Kai Banner
Kongou-class Kai NiKongou Kai Ni C Banner
Hiei Kai Ni Banner
Kirishima Kai Ni Banner
Haruna Kai Ni Banner
QF 2-pounder + 16inch Mk.I Triple + FCR
20-tube 7inch UP + 20-tube 7inch UP / QF 2-pounder
33 HG
+4 1.35 Gotland KaiGotland Kai Banner HA + AA Gun
34 5inch Single Gun Mount Mk.30 Kai + GFCS Mk.37 308 Card5inch Single Gun Mount Mk.30 Kai + GFCS Mk.37 308 Card +8 1.6 Fletcher-ClassFletcher Kai Banner
Johnston Kai Banner
35 5inch Single Gun Mount Mk.30 Kai + GFCS Mk.37 308 Card5inch Single Gun Mount Mk.30 Kai 313 Card +7 1.55 The 5inch Single Gun Mount Mk.305inch Single Gun Mount Mk.30 284 Card can also be used in place of the Kai variant.
36 5inch Single Gun Mount Mk.30 Kai 313 Card5inch Single Gun Mount Mk.30 Kai 313 CardGFCS Mk.37 307 Card +7 1.55
37 5inch Single Gun Mount Mk.30 Kai 313 Card5inch Single Gun Mount Mk.30 Kai 313 Card +5 1.45
38 Unknown
39 GFCS Mk.37 + 5inch Twin Dual-purpose Gun Mount (Concentrated Deployment) 363 Card5inch Twin Dual-purpose Gun Mount (Concentrated Deployment) 362 Card +11 1.7 Atlanta-classAtlanta Kai Banner
40 5inch Twin Dual-purpose Gun Mount (Concentrated Deployment) 362 Card5inch Twin Dual-purpose Gun Mount (Concentrated Deployment) 362 CardGFCS Mk.37 307 Card +11 1.7 The GFCS+5inch(CD)GFCS Mk.37 + 5inch Twin Dual-purpose Gun Mount (Concentrated Deployment) 363 Card variant of the gun can also be used.
41 5inch Twin Dual-purpose Gun Mount (Concentrated Deployment) 362 Card5inch Twin Dual-purpose Gun Mount (Concentrated Deployment) 362 Card +10 1.65 The GFCS+5inch(CD)GFCS Mk.37 + 5inch Twin Dual-purpose Gun Mount (Concentrated Deployment) 363 Card variant of the gun can also be used.
  • CDMG and Customized HA plus AAFD icon are provisional icons to display CDMG and Built-in HA Mount-type guns.
    • Built-in HA mount is defined as a single GreenGunDP High-Angle gun that has 8Icon AA stat or higher.
    • CDMG is defined as any Anti-Air gun that has 9Icon AA stat or higher.
  • API 1/2 are the only AACIs that can be activated with any Radar regardless of AA Stat. All other AACIs require that a radar with at least 2 Icon AA or higher be equipped.
  • The probability of AACI occurring is fixed (Approx 40-65% depending on API) and is not affected by any in-game stat.
  • If a ship fulfills multiple requirements, the API with the highest priority will be checked first
    • A single roll is done to check for all AACIs in descending priority. This means that an AACI with lower priority but higher trigger chance can occur.
    • For instance Akizuki with 2 akiguns and a T13K air radar fulfills the requirements of AACI with API values 1, 2, 3, 5, 8 - the only API that will ever trigger is 1. This is because API 1 has both the highest trigger probability and priority. In the event that the Akizuki fails the roll for API 1, no other AACI can succeed as their trigger probabilities are below that of API 1.
    • Fletcher-class and Atlanta AACIs (API 34-37 & API 39-41) have the unique exception of independently rolling for each AACI they currently fulfil the conditions of. If all these rolls fail, they will roll an additional time for API 5. This effectively drastically increases their AACI chance when fulfilling multiple conditions.
    • AACI priority is currently being determined, but some notable situations are highlighted below.
      • For instance, AACI with the API values of 7 and 8 can both be triggered by the same ship if she has fulfilled both requirements.[11]
      • Another instance of that happening is with API values 19 and 20. Kinu Kai Ni can trigger API 20 as well if she fulfills the requirements for API 19.
      • The same thing happens with API 8 and 20, 5 and 29.
  • If multiple ships fulfill AACI requirements, the one with the highest API number will be triggered first
    • Due to higher API numbers having priority rather than AACI strength, a weaker AACI may be triggered first if present in the fleet. Take note when equipping your fleet.

Stage 3

Opening Air Strike

  • Bombers attack ships in this stage[12]
    • If Detection fails, this stage will not occur.
  • Each slot's planes would target one ship and attack for one time.
  • $ Damage=\lfloor (\lfloor cap_{150}\{(25 + P\sqrt{N})R\}C_v \rfloor T-A)L \rfloor $[13]
    • $ P $ refer to bombing or torpedo value
    • $ N $ refer to number of plane in the slot
    • $ R $ is a fixed $ 1.0 $ for Dive Bombers, but is a random $ 0.8 $ or $ 1.5 $ for Torpedo Bombers/[14]
      • The probability for Torpedo Bombers acquiring an $ 1.5 $ multiplier in 1-1-A is around 50% [15]
    • $ cap_{150}(x) $ refer to the attack power cap, see Combat page for detail.
    • $ C_v $ refer to Critical hit bonus from Aircraft Proficiency system. See Combat page and Aircraft Proficiency for details about its effect and etc.
      • If you bring more proficient planes, the rate to trigger it would increase.[16]
      • With max proficiency Suisei Model 12A on 3 slot of a ship, critical hit rate is around 20%.[17]
    • $ T $ refer to contact multiplier, $ 1.0 $ if contact failed
    • $ A $ refer to enemy armor, see Combat page for detail.
    • $ L $ refer to ammo modifier, see Combat page for detail.
  • No effect from engagement/formation/ship health when they launch planes/morale/fatigue on firepower or accuracy. [18]
  • Affected by the Aircraft Proficiency system.[16][17]
  • Carrier's level and plane's accuracy stat do not affect this stage.[19]
    • Accuracy is around 80% against destroyers in 1-1-A.

Anti-air Propellant Barrage

Added during the 2018 January 27 update, Anti-air Propellant Barrage (AAPB) is a system by which bombing damage can be negated on individual ships. Unlike other anti-air mechanics, this mechanic negates damage instead of reducing enemy bomber counts.

Activation requirements

To trigger:

Activation chance

Each ship triggers AAPB individually. Activation chance is affected by:

  • Ship adjusted AA
  • Ship luck Icon Luck
  • Ise-class bonus
  • Number of 12cm 30-tube Rocket Launcher Kai Ni equipped on ship

Activation chance can be estimated by:

$ \text{AAPB}% = \frac{AdjustedAA + 0.9 \cdot Luck}{281} + (N - 1) \cdot 15 + C_b $[20]

  • $ N $ is number of 12cm 30-tube Rocket Launcher Kai Ni equipped.[21]
  • $ C_b $ is the class bonus, 25 for Ise-class BBVs.


  • There seems to be diminishing returns on luck. The exact relationship is still unclear.[22]
  • It's possible to achieve 100% activation rate.
  • The formula above is only for 12cm 30-tube Rocket Launcher Kai Ni, there are two other barrages: Type 3 Shell and Type 3 Shell + Rocket Launcher Kai Ni. Effects and trigger chance currently unknown.


  • The ship card will slide forward, and the text "噴進弾幕成功" will be displayed on the right.

    Anti-air Propellant Barrage visual effects

  • Any damage to the ship(s) performing AARB by opening airstrikes will be negated (no damage or miss text is shown).

Note that activation of AARB does not mean the ship was targeted by opening airstrikes.

Jet Assault

If any carriers on either side are equipped with jet-powered aircraft, a Jet Assault phase will commence before the main aerial combat phase and Land Base Aerial Support phases.

If jet-powered aircraft exist in the Land Base Aerial Support phase, then that aircraft with perform its own Jet Assault phase before the main Land Base Aerial Support.

Jet Assault phase will not take place where aerial combat does not happen, for instance in night battle nodes or anti-submarine-only nodes. Additionally, Jet Assault will not occur in Air Raid node.

Ships sank by jets in Jet Assault phase will not launch planes for aerial combat and is likely not going to commence anti-air fire, however their anti-air equipment would still contribute to Fleet Anti-Air. [23]

The jet assault phase does not involve the contact mechanic.[24]

The mechanics of this phase are identical to the standard air combat phase, however only jet aircraft on both sides will be able to participate.


  1. 1.75 in Vita
  2. 1.55 in Vita
  3. 1.5 in Vita
  4. 1.45 in Vita
  5. Non-MayaK2, Akigun + CDMG + AA Radar, 35%, +4, K-value 1.35


  1. Example on how to calculate a ship's fighter power using the formula. Akagi Kai's fighter power with Reppuu in slots 1 and 2, Reppuu Kai in slot 3, Type 0 Fighter Model 62 (Fighter-bomber) in slot 4. All aircraft without proficiency. $ \begin{align} F_{Power} & = \left \lfloor \sqrt{N_{\text{Slot1}}} \cdot E_{\text{Reppuu}} \right \rfloor + \left \lfloor \sqrt{N_{\text{Slot2}}} \cdot E_{\text{Reppuu}} \right \rfloor + \left \lfloor \sqrt{N_{\text{Slot3}}} \cdot E_{\text{ReppuuKai}} \right \rfloor + \left \lfloor \sqrt{N_{\text{Slot4}}} \cdot E_{\text{M62}} \right \rfloor \\ & = \left \lfloor \sqrt{20} \cdot 10 \right \rfloor + \left \lfloor \sqrt{20} \cdot 10 \right \rfloor + \left \lfloor \sqrt{32} \cdot 12 \right \rfloor + \left \lfloor \sqrt{10} \cdot 4 \right \rfloor \\ & = 44 + 44 + 67 + 11 \\ & = 166 \end{align} $


  10. used to be Z+4 before 2016-01-19 update
  13. shitaraba 6-502,515,531,540,
  14. shitaraba 6-531,540,攻1-601
  15. shitaraba 6-533,539
  16. 16.0 16.1
  17. 17.0 17.1
  18. shitaraba 4-531,576,579
  19. shitaraba攻1-119,121
  20. See Noratako's posts: See also his newer research Further verification still needed.
  21. Minegumo Teitoku (@hata_mine) reports that three 12cm 30-tube Rocket Launcher Kai Ni may increase the activation chance by 30%: The details of the testing are, however, not provided.
  22. For instance, Muu suggests the existence of Luck cap. See
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