Flooding
Some browsers may not be able to expand the tables below.
If you have trouble viewing them there is a fully expanded version of this page here.
(link)
Learn more about flooding. 16 May 2019
Contents
Causing Flooding
Only three effects have a chance to cause a ship to flood:
- Being struck by an enemy torpedo.
- Being rammed by an enemy ship.
- Being hit by a depth charge as a submarine.
It is impossible to cause a flooding on an allied ship.[1] Underwater shell hits can cause damage but do not cause flooding.
A ship is immune from flooding during the action time of its Damage Control Party 
.
A ribbon is awarded when a flood is caused to an enemy ship. Though captains may be awarded multiple flooding ribbons, it is not possible for a ship to suffer from the effects of more than two floods concurrently: one forward and one aft. In the case of submarines, only one active flood is possible, in the amidship section.
Flooding Chance
Ramming causes flooding in the impacted section if the ram causes 10% or more damage to the ship.
The probability of a ship flooding from a torpedo strike depends on:
- the base flooding chance of the torpedo,
- the presence and quality of a Torpedo Protection System,
- where the ship is struck,
- the presence of upgrades and signals mounted on the ships,
- the skills possessed by the attacking and defending commanders.
All ships — except destroyers and submarines — have torpedo protection for their citadel. As a result, the chance of flooding and damage are reduced even if the ship doesn't have "Torpedo Protection" displayed on the Port screen. Destroyers and submarines do not have any torpedo protection, so the torpedo damage reduction bonus of Damage Control System Modification 1 
will not function when the upgrade is mounted on a destroyer. (Yet another argument in favor of Engine Room Protection 
.)
Base chance
Flood chance when striking anywhere but the ship's anti-torpedo belt.
Where:
- FCB - Base flooding chance
- FCT - Torpedo flood chance (from the tables below)
- SVL = 1.04 if the attacking ship flies the Victor Lima
signal flag, else 1
- SJWU = 1.15 if the attacking ship flies the Juliet Whiskey Unaone
signal flag, else 1
- KLQ = 1.30 if the attacking commander has the Liquidator skill, else 1
Against a Torpedo Protection System
Flood chance when striking a ship's anti-torpedo belt
Where:
- FCTP - Flooding chance against a ship's Torpedo Protection system
- FCB - Base flooding chance
- UDCS - 0.97 if the Damage Control System Modification 1 upgrade is mounted and the ship is not a destroyer, else 1
- TP - Damage reduction of the ship's Torpedo Protection system (ship specific; roughly 0-50%)
- KTP - 0.07 if the defending commander has the Vigilance skill, else 0
- KPF - 0.10 if the attacking commander has the Proximity Fuze skill, else 0
Ship-Launched Torpedo Data
Aerial Torpedo Data
Flooding Effects
There are two parts of the ship that can flood — the forward half and the aft half. Thus there can be two simultaneous floods (only one with submarines).
Aircraft carriers, destroyers, and cruisers take 0.25% hit points of damage per second per flood; battleships and large cruisers[1] take 0.5% hit points of damage per second per flood; Admiral Graf Spee takes 0.375% hit points of damage per second per flood; and submarines take 0.33% hit points of damage per second per flood.
In addition, ships that are flooding have their top speed reduced by 30% at full speed forward, and 60% at reverse. There are also blinking red lights on its superstructure.
Controlling and Repairing Flooding
Flooding can be stopped in one of two ways:
- activating the Damage Control Party consumable,
- or waiting for the flood duration timer to expire.
All damage sustained by flooding is 100% recoverable by ships that can use the Repair Party 
consumable.
Flooding Duration
Flooding has a base duration of 30 seconds for carriers and submarines and 40 seconds for the other classes.
Flooding duration cannot be extended by subsequent strikes on a part of the ship that is already flooding. Otherwise, flooding duration can be altered in several ways:
- Activation of the Damage Control Party will stop flooding immediately.
- Equipping Slot 4 upgrade Damage Control System Modification 2 will reduce the duration by 15%.
- A battleship commander's Basics of Survivability skill will reduce the duration by 15%.
- In contrast, the Super-Heavy AP Shells battleship skill will extend the duration by 30%.
- Flying the Juliet Yankee Bissotwo
signal will reduce the duration by 20%.
Each of these effects stacks with the others; however, they are multiplicative rather than additive.
For example, if Damage Control System Modification 2 and Juliet Yankee Bissotwo are stacked, the flooding duration is:
40 seconds x 0.85 x 0.80 = 27.2 seconds.
The below tables provides the flood durations and total health loss for the different combinations of the modifiers. Full flood duration uninterrupted by Damage Control Party is assumed.
| Modifiers | Duration | Single Flood | Double Flood |
|---|---|---|---|
| none | 30 seconds | 7.5% of base health | 15% of base health |
| With a -15% modifier | 25.5 seconds | 6.38% of base health | 12.75% of base health |
| With a -20% modifier | 24 seconds | 6% of base health | 12% of base health |
| With both modifiers | 20 seconds | 5.1% of base health | 10.2% of base health |
| Modifiers | Duration | Total Damage |
|---|---|---|
| none | 40 seconds | 20.0% of base health |
| -15% | 34 seconds | 17.0% of base health |
| -20% | 32 seconds | 16.0% of base health |
| -15%, -15% | 28.9 seconds | 14.5% of base health |
| -15%, -20% | 27.2 seconds | 13.6% of base health |
| -15%, -15%, -20% | 23.1 seconds | 11.6% of base health |
| +30% | 52 seconds | 26.0% of base health |
| -15%, +30% | 44.2 seconds | 22.1% of base health |
| -20%, +30% | 41.6 seconds | 20.8% of base health |
| -15%, -15%, +30% | 37.6 seconds | 18.8% of base health |
| -15%, -20%, +30% | 35.4 seconds | 17.7% of base health |
| -15%, -15%, -20%, +30% | 30.1 seconds | 15.0% of base health |
| Modifiers | Duration | Total Damage |
|---|---|---|
| none | 40 seconds | 20.0% of base health |
| With a -15% modifier | 34 seconds | 17.0% of base health |
| With a -20% modifier | 32 seconds | 16.0% of base health |
| With both modifiers | 27.2 seconds | 13.6% of base health |
| Modifiers | Duration | Total Damage |
|---|---|---|
| none | 40 seconds | 15.0% of base health |
| With a -15% modifier | 34 seconds | 12.75% of base health |
| With a -20% modifier | 32 seconds | 12.0% of base health |
| With both modifiers | 27.2 seconds | 10.2% of base health |
| Modifiers | Duration | Total Damage |
|---|---|---|
| none | 40 seconds | 10.0% of base health |
| With a -15% modifier | 34 seconds | 8.5% of base health |
| With a -20% modifier | 32 seconds | 8.0% of base health |
| With both modifiers | 27.2 seconds | 6.8% of base health |
| Modifiers | Duration | Total Damage |
|---|---|---|
| none | 30 seconds | 9.9% of base health |
| With a -15% modifier | 25.5 seconds | 8.4% of base health |
| With a -20% modifier | 24 seconds | 7.9% of base health |
| With both modifiers | 20.4 seconds | 6.7% of base health |
Notes
Sources
Updated Mechanics for Flooding News article 12-Feb-2019.
Endnotes
- ↑ 1.0 1.1 This group includes Tier VII Toulon, Tier VIII Congress, Cherbourg, Haarlem and Schill, Tier IX Admiral Schröder, Ägir, AL Ägir, Mengchong, Alaska, Alaska B, Azuma, Azuma B, AL Azuma, Brest, Carnot, Johan de Witt, Kronshtadt, Michelangelo and Siegfried, and Tier X Defence, Gouden Leeuw, Marseille, Puerto Rico, Sevastopol, Stalingrad, Yoshino and Yoshino B.
