There are two different things that can potentially cause a ship to catch on fire:
- Being struck by a high explosive shell (enemy or friendly).
- Being struck by an aircraft bomb (enemy or friendly).
A ribbon is awarded when a fire is caused on an enemy ship; captains are awarded a "Set on Fire" ribbon for each individual fire that they set. Every ship has four distinct areas along its main deck that can be set on fire. Fires may be set by high explosive shells — including those fired by secondary batteries — or by bomber aircraft according to the fire chance of the individual shell or bomb and the fire resistance of the targeted ship.
Each ship hull in the game has a fire resistance coefficient. These are not specific to individual ships and are dictated solely based on ship tier and the currently equipped hull (premium ships always use the Top Hull coefficient for their tier). Due to how fire chance is calculated, the lower the coefficient, the more resistant a ship is to catching fire. The coefficients are shown below:
|Ship Tier|| Fire Resistance Coefficient
| Fire Resistance Coefficient
| Fire Resistance Coefficient|
The chance to set fire for a single high explosive shell (or aircraft bomb) hitting a section is calculated by the following formula:
- The value of "Damage Control Modification 1" is 0.05 if the appropriate upgrade is installed; otherwise, it is zero.
- The value of "Fire Prevention" is 0.10 if a commander with the appropriate Commander skill is in command of the ship that is under attack; otherwise, it is zero.
- "Projectile Base Fire Chance" is displayed in the Port screen — for high-explosive shells — by mousing over the Main Battery information underneath the Artillery tab. For aircraft bombs, the base fire chance is a fixed number based on the size and type of ordnance used and varies between 1.08 (for the 140 lb. bombs carried by Kaga) and 1.65 (for the 1000 kg bombs deployed aboard Graf Zeppelin). See the Aerial Combat page for more info.
- "Demolition Expert" is 0.02 if a commander with the appropriate skill is in command of the ship that fired the shell (or dropped the bomb); otherwise, it is zero.
- "Signals" varies depending on which signals are equipped; both Victor Lima () and India X-Ray () can increase the fire chance of high-explosive shells.
As an example, we can compare the chance of a single Benson high explosive shell lighting a fire on an enemy Bismarck. The Bismarck is using Hull (B) and Damage Control Modification 1, but her commander does not have Fire Prevention. The Benson commander has Demolition Expert (but not Inertia Fuse for HE Shells) and is flying both the Victor Lima and India X-Ray signals. The fire chance would be:
(0.6337) x (1 - 0.05 - 0.00) x (0.05 + 0.02 + 0.005 + 0.005 - 0.00) = 4.82% fire chance
If the Bismarck commander acquires the Fire Prevention skill, the chance would then be:
(0.6337) x (1 - 0.05 - 0.10) x (0.05 + 0.02 + 0.005 + 0.005 - 0.00) = 4.31% fire chance
If the Benson commander didn't have Demolition Expert or the signals equipped, the chance would be:
(0.6337) x (1 - 0.05 - 0.10) x (0.05 + 0.00 + 0.00 - 0.00) = 2.69% fire chance
The above example can be used to demonstrate the usefulness of the Demolition Expert on certain ships, especially those with a high rate of fire and a low individual fire chance per shell (such as Atlanta, Gearing, or Akizuki).
Damage dealt by each instance of fire on a ship is fixed as 0.3% of its total health pool per fire per second (0.4% for aircraft carriers). Each fire has a base duration of 60 seconds for battleships and aircraft carriers, and 30 seconds for cruisers and destroyers. A fire which is allowed to burn for the full duration on a battleship will consume 18% of a ship's maximum health (24% for carriers). Captains of capital ships — aircraft carriers and battleships — can quickly see, then, that while one fire might be considered a nuisance, two or more are a major threat to their ship.
Other Effects of Fire
- Ships that are on fire have their surface detection range increased by 2.0 km and their aerial detection radius increased by 3.0 km. This is particularly noteworthy for destroyer captains.
- Aircraft carriers that are on fire cannot launch or recover aircraft, unless their commander has trained the Emergency Takeoff skill which allows planes to take off and land while the flight deck is on fire at the cost of double the servicing time.
Fires can only be extinguished by utilization of the Damage Control Party () consumable, or by waiting for the fire duration timer to expire. The duration of a fire can be reduced in several ways:
- Equipping Damage Control System Modification 2 () will reduce the duration by 15%.
- Using a commander with the Level 3 commander skill Basics of Survivability will reduce the duration by 15%.
- Flying the India Yankee () signal will reduce the duration by 20%.
Each of these effects stacks with the others; however, they are multiplicative rather than cumulative.
For example, if all three reduction effects are stacked, the duration of a single fire on a battleship or carrier is: 60 seconds x 0.85 x 0.85 x 0.80 = 34.68 seconds.
The below tables provide the fire durations and total health loss for the different combinations of the above three effects.
|Modifiers||Total Damage to Battleships||Total Damage to Carriers||Duration|
|Total damage||18% of base health||24% of base health||60 seconds|
|With one -15% modifier||15.3% of base health||20.4% of base health||51 seconds|
|With a -20% modifier||14.4% of base health||19.2% of base health||48 seconds|
|With two -15% modifiers||13.005% of base health||17.34% of base health||43 seconds|
|With one -15% modifier and a -20% modifier||12.24% of base health||16.32% of base health||41 seconds|
|With two -15% modifiers and a -20% modifier||10.404% of base health||13.872% of base health||35 seconds|
|Total damage||9% of base health||30 seconds|
|With one -15% modifier||7.7% of base health||26 seconds|
|With a -20% modifier||7.2% of base health||24 seconds|
|With two -15% modifiers||6.5% of base health||22 seconds|
|With one -15% modifier and a -20% modifier||6.12% of base health||20 seconds|
|With two -15% modifiers and a -20% modifier||5.2% of base health||17 seconds|
All damage sustained by fires is 100% eligible for recovery by ships that can use the Repair Party () consumable. Note that a standard Repair Party heals up to 14% of a ship's base health (16.8% with the India Delta () signal) over 28 seconds, comparable to a single fire on a battleship depending on other modifiers.