Combat/Opening Anti-Submarine Warfare

Introduction

During the opening phases of combat, ships which meet certain requirements are able to perform opening ASW attacks. These attacks are valuable because they have the opportunity to sink submarines before they get the chance to perform opening torpedoes.

Overview

1. All ships with an ASW   stat are capable of performing OASW.

  • Theoretically any ship capable of ASW is able to perform OASW but no equipment exists that allows normal CVL, CAV and BBV to hit the 100 ASW threshold.

2. Upgrades to ASW equipment are not counted towards the thresholds for triggering OASW.

3. OASW attacks are performed in range order.

  • Attacks from ships with the same range are random.

4. Damage is calculated the same way as normal ASW.


Trigger Requirements

Ship Requirement
All ASW capable ships
  • 100≤ ASW
Destroyer Escorts

Either:

  • 60≤ ASW with sonar
  • 75≤ ASW with equipment that has 4≤ ASW
Isuzu Kai Ni
Tatsuta Kai Ni
Jervis Kai
Janus Kai
Samuel B. Roberts Kai
Fletcher
Johnston
  • Default OASW regardless of ASW stat or equipment.
Taiyou
Shinyou
Gambier Bay
Zuihou Kai Ni B

Have both:

  • 65≤ ASW
  • At least 1 plane with 7≤ ASW
Taiyou Kai/Kai Ni
Shinyou Kai Kai Ni
  • 65≤ ASW
Hyuuga Kai Ni

Either:

Minimum OASW Level

The minimum level for OASW can be calculated using:


[math]\displaystyle{ \text{Level}_\text{min} = \bigl\lceil \left( \left(\text{OASW}-\text{ASW}_\text{equip} \right) - \text{OASW}_\text{min} \right) \times \frac{99}{\text{OASW}_\text{max}-\text{OASW}_\text{min}} \bigr\rceil }[/math]

  • [math]\displaystyle{ \text{OASW}_\text{min} }[/math] is the minimum ASW of the ship as noted in the tables below.
  • [math]\displaystyle{ \text{OASW}_\text{max} }[/math] is the maximum ASW of the ship as noted in the tables below.
  • [math]\displaystyle{ \text{ASW}_\text{equip} }[/math] is the total base ASW provided by equipment.
  • [math]\displaystyle{ \text{OASW} }[/math] is the relevant OASW threshold.
    • [math]\displaystyle{ 60 }[/math] for DEs with sonars.
    • [math]\displaystyle{ 75 }[/math] for DEs without sonars and ASW equipment that have 4≤ ASW.
    • [math]\displaystyle{ 65 }[/math] for CVLs with 7≤ ASW planes OR Taiyou/Shinyou Kai/Kai Ni
    • [math]\displaystyle{ 100 }[/math] for all other ships.


Minimum OASW Chart

The following apply to the tables below:

  • Only easily obtainable equipment combinations are shown.
  • The equipment abbreviations are:
  • Ships with default ASW as detailed in the section above aren't listed.
  • Numbers in brackets are the total ASW of the equipment setup.
  • Only the top remodel is applicable unless otherwise stated.
  • If you require minimum OASW levels for remodels or equipment combinations that aren't listed, you can use the formula above and minimum and maximum ASW stats on the ship girl pages.


Destroyers
Ship Min ASW Max ASW
3 Slots 2 Slots 1 Slot 4 Slots
T4S/T4S/T4S
(36)
T4S/T4S/T3CP
(32)
T3S/T3S/T3S
(30)
T3S/T3S/T3DCP
(28)
T3S/T3DCP/T2DC
(25)
T4S/T4S
(24)
T3S/T3S
T4S/T3DCP
(20)
T3S/T3DCP
(18)
T4S
(12)
T3S
(10)
T4S/T4S/T4S/T3DCP
(44)
T3S/T3S/T3S/T3DCP
(38)
T3S/T3S/T3DCP/T2DC
(35)
Asashio Kai Ni D 45 89 85 85 85 85 85 85 85 85 97 102 - - -
Urakaze D Kai 45 88 69 69 69 69 70 72 81 86 99 104 - - -
Tanikaze D Kai 44 86 70 70 70 70 74 76 85 90 104 109 - - -
Maestrale Kai
Libeccio Kai
40 80 60 70 75 80 87 90 99 104 119 124 - - -
Grecale Kai 38 79 63 73 78 83 90 92 102 107 121 126 - - -
Shiratsuyu Kai Ni 30 83 77 77 77 79 85 86 94 98 109 113 - - -
Arare Kai Ni 33 81 64 73 77 81 87 89 97 102 114 118 - - -
Umikaze Kai Ni 28 82 82 82 82 82 87 88 96 99 110 114 - - -
Satsuki Kai Ni 30 81 75 75 78 82 88 90 98 101 113 117 - - -
Fumizuki Kai Ni 30 81 77 77 78 82 88 90 98 101 113 117 - - -
Asashimo Kai 35 79 66 75 79 84 90 93 102 106 120 124 - - -
Kazagumo Kai Ni 29 78 75 79 83 87 93 95 104 108 120 124 - - -
Verniy 30 77 72 81 85 89 95 97 106 110 123 127 - - -
Yuugumo Kai Ni 30 77 75 81 85 89 95 97 106 110 123 127 - - -
Tashkent Kai 40 73 72 84 90 96 105 108 120 126 144 150 50 66 75
Murasame Kai Ni 29 77 73 81 85 89 95 97 106 110 122 126 - - -
Shigure Kai Ni 31 76 73 82 86 91 97 99 108 113 126 130 - - -
Ushio Kai Ni 32 75 74 83 88 93 99 102 111 116 129 134 - - -
Hamakaze B Kai 32 72 80 90 95 99 107 109 119 124 139 144 - - -
Makigumo Kai Ni
Kishinami Kai
Akizuki Kai
Teruzuki Kai
Hatsuzuki Kai
30 72 81 90 95 99 107 109 118 123 137 142 - - -
Hatsushimo Kai Ni 28 72 81 90 95 99 106 108 117 122 135 140 - - -
Suzutsuki Kai 28 71 83 93 97 102 109 111 120 125 139 143 - - -
Harukaze Kai 22 72 84 92 96 99 105 107 115 119 131 135 - - -
Okinami Kai 32 70 84 94 99 105 113 115 126 131 146 152 - - -
Kuroshio Kai Ni
Isokaze B Kai
31 70 84 94 99 105 112 115 125 130 145 150 - - -
Z1 Zwei
Z3 Zwei
37 69 84 96 103 109 118 121 134 140 158 164 - - -
Arashi Kai 30 70 85 95 99 104 112 114 124 129 144 149 - - -
Kamikaze Kai 24 70 87 95 99 104 110 112 121 125 138 143 - - -
Hatakaze Kai 21 70 87 95 99 104 110 112 120 124 136 140 - - -
Hatsuharu Kai Ni
Yamakaze Kai
30 69 87 97 102 107 115 117 127 132 148 153 - - -
Mutsuki Kai Ni
Murakumo Kai Ni
Yuudachi Kai Ni
28 69 87 97 102 107 114 116 126 131 145 150 - - -
Matsukaze Kai 20 70 88 96 99 103 109 111 119 123 135 139 - - -
Kisaragi Kai Ni 27 69 88 97 102 107 114 116 125 130 144 149 - - -
Hayanami Kai 26 69 88 97 102 106 113 116 125 129 143 148 - - -
Shiranui Kai Ni
Naganami Kai Ni
30 68 89 99 105 110 118 120 131 136 152 157 - - -
Kasumi Kai Ni/B
Nowaki Kai
Hagikaze Kai
28 68 90 99 104 109 117 119 129 134 149 154 - - -
Maikaze Kai 27 68 90 99 104 109 116 119 128 133 148 153 - - -
Fubuki Kai Ni 26 68 90 99 104 109 116 118 128 132 147 151 - - -
Kagerou Kai Ni 30 67 91 102 108 113 121 124 134 140 156 161 - - -
Asakaze Kai 18 68 92 99 103 107 113 115 123 127 139 143 - - -
Takanami Kai
Hayashimo Kai
Kiyoshimo Kai
29 67 92 102 107 113 120 123 133 139 154 159 - - -
Oyashio Kai 27 67 92 102 107 112 119 122 132 137 151 156 - - -
Akatsuki Kai Ni
Fujinami Kai
28 66 94 105 110 115 123 126 136 141 157 162 - - -
Hamanami Kai 28 65 97 108 113 118 126 129 140 145 161 166 - - -
Uzuki Kai 21 65 97 106 111 115 122 124 133 138 151 156 - - -
Yamagumo Kai
Hatsukaze Kai
Akigumo Kai
27 64 99 110 116 121 129 132 142 148 164 169 - - -
Ooshio Kai Ni
Tokitsukaze Kai
26 64 99 110 115 120 128 131 141 146 162 167 - - -
Ayanami Kai Ni
Kawakaze Kai Ni
25 63 102 113 118 123 131 133 144 149 165 170 - - -
Minazuki Kai 19 61 107 116 121 125 132 135 144 149 163 168 - - -
Michishio Kai Ni 26 60 111 123 129 134 143 146 158 164 - - - - -
Yayoi Kai
Nagatsuki Kai
Kikuzuki Kai
Mikazuki Kai
Mochizuki Kai
18 59 112 121 126 131 138 141 150 155 170 174 - - -
Asashio Kai Ni
Arashio Kai Ni
26 59 114 126 132 138 147 150 162 168 - - - - -
All other destroyers 24 59 114 125 131 136 145 148 159 165 - - - - -
Amatsukaze Kai 28 59 115 128 135 141 151 154 167 173 - - - - -
Yukikaze Kai
Shimakaze Kai
27 59 115 127 134 140 149 152 164 171 - - - - -
Shimakaze Kai 27 59 115 127 134 140 149 152 164 171 - - - - -
Minegumo Kai 24 58 117 129 134 140 149 152 164 169 - - - - -
Light Cruisers
Ship Min ASW Max ASW
3 Slots 2 Slots 1 Slot 4 Slots
T4S/T4S/T4S
(36)
T4S/T4S/T3CP
(32)
T3S/T3S/T3S
(30)
T3S/T3S/T3DCP
(28)
T3S/T3DCP/T2DC
(25)
T4S/T4S
(24)
T3S/T3S
T4S/T3DCP
(20)
T3S/T3DCP
(18)
T4S
(12)
T3S
(10)
T4S/T4S/T4S/T3DCP
(44)
T3S/T3S/T3S/T3DCP
(38)
T3S/T3S/T3DCP/T2DC
(35)
Kinu Kai Ni 49 86 75 75 75 75 75 75 83 89 105 110 - - -
Naka Kai Ni 48 85 48 54 59 65 73 75 86 91 108 113 - - -
Yura Kai Ni 49 83 77 77 77 77 77 79 91 97 114 120 - - -
Abukuma Kai Ni 48 82 75 75 75 75 79 82 94 99 117 123 - - -
Tama Kai Ni 43 83 70 70 70 72 80 82 92 97 112 117 - - -
Jintsuu Kai Ni 40 80 60 70 75 80 87 90 99 104 119 124 - - -
Sakawa Kai 30 84 63 70 74 77 83 85 92 96 107 110 - - -
Kiso Kai Ni 32 82 64 72 76 80 86 88 96 99 111 115 - - -
Agano Kai
Noshiro Kai
Yahagi Kai
26 82 68 75 78 82 87 89 96 99 110 114 - - -
Kitakami Kai Ni
Ooi Kai Ni
27 79 71 79 82 86 92 94 101 105 117 120 - - -
Kuma Kai
Nagara Kai
Natori Kai
24 79 72 80 83 87 92 94 101 105 116 119 - - -
Sendai Kai Ni 38 74 72 83 88 94 102 105 116 121 138 143 - - -
Tenryuu Kai Ni 24 70 87 95 99 104 110 112 121 125 138 143 - - -
Yuubari Kai 24 69 88 97 102 106 113 115 124 128 141 146 71 84 91
Gotland Kai 38 62 108 124 132 141 153 157 174 - - - 75 99 112
Giuseppe Garibaldi Kai 25 60 111 122 128 133 142 145 156 162 - - 88 105 114
Duca degli Abruzzi Kai 25 59 114 126 132 137 146 149 161 166 - - 91 108 117
Ooyodo Kai 0 39 163 173 - - - - - - - - 143 158 165
Destroyer Escorts[1]
Ship Min ASW Max ASW
2 Slots 1 Slot
T4S/T4S
(24)
T3S/T3S
T4S/T3DCP
(20)
T3S/T3DCP
(18)
T4S
(12)
T3S
(10)
Shimushu 32 72 10 20 25 40 45
Kunashiri 31 70 13 23 28 44 49
Ishigaki 32 75 10 19 24 37 42
Hachijou 31 72 13 22 27 42 46
Etorofu
Matsuwa
Tsushima
Fukae
35 72 3 14 19 35 41
Sado 36 73 1 11 17 33 38
Mikura
Hiburi
40 78 1 1 6 21 27
Daitou 40 77 1 1 6 22 27
  1. Only values for base remodels are calculated because all DEs are capable of 1-slot OASW on Kai.
Light Carriers[1]
Ship Min ASW Max ASW
931/931/931
(21)
931/931
(14)
931/
(7)
Taiyou 35 69 30 47 67
Shinyou 36 60 33 62 91
Zuihou Kai Ni B 32 48 75 118 161
Gambier Bay Kai 30 68 45 55 73
  1. Only values for base remodels are calculated for Taiyou and Shinyou because they are capable of 1-slot OASW on Kai and Kai Ni.