- 1 Detectability range
- 2 Spotting range
- 3 Consumables
- 4 Fuel spills
- 5 Proximity spotting
- 6 Torpedoes
- 7 Radio Location Commander Skill
- 8 Watchful
- 9 Situational Awareness
- 10 Thunderstorm Fronts
- 11 Notes
A ship or aircraft is detected or 'spotted' when an enemy ship or aircraft gets close enough to detect it, and if necessary for the type of detection, has line of sight (LoS) to it. An enemy that is spotted can be targeted for destruction.
The most important value is detectability range, which is divided into two categories:
- Detectability Range by Sea (surface detectability range): This is the range at which a ship or aircraft will be detected by an enemy ship. A Line of Sight (LoS) is required between the spotting ship and the ship/aircraft being spotted. A ship will not be spotted by an enemy ship if there are no enemy ships within this range.
- Detectability Range by Air (air detectability range): This is the range at which a ship or aircraft will be detected by an enemy aircraft. For ships, this is usually shorter than the detectability range by sea. A line of sight is required between the spotting aircraft and the ship/aircraft being spotted. This is also the concealment value that is used for interactions between ships and submarines at periscope depth.
Attack aircraft, dive bombers, skip bombers and torpedo bombers usually have a detectability range (both by sea and by air) of 10 km (Japanese torpedo bombers: 7.5 km). Tier ★ tactical squadrons of all types have a 15 km detectability range.
Launching torpedoes or firing secondary guns will not increase a ship's detectability ranges. Sailing slowly or stopping completely will not reduce a ship's detectability. Emitting a sonar ping does not increase the detectability of submarines.
At maximum depth, submarines cannot detect enemy ships or submarines, and their visibility of enemy ships detected by allies is reduced, about 8-10 km on average.
There is a period of guaranteed acquisition: if a ship is detected by an opponent, it will remain visible to the enemy for at least 2 seconds. This prevents an enemy ship from "flickering" at the edge of the line of sight—i.e. appearing and disappearing from the map in rapid succession.
As a result, if your ship leaves an opponent's line of sight 1 second after you were detected, you'll continue to be visible to the enemy ship for a further 1 second. However, if your ship was visible to the enemy ship for 2 seconds before leaving the enemy ship's line of sight, you'll disappear from the enemy's view immediately.
Firing main guns
Firing main guns will increase sea detectability ("bloom") to the current maximum range of the main guns. Air detectability will also increase by a smaller amount depending on the ship (and it is possible in this situation for air detectability range to exceed sea detectability, e.g König). If the ship is detected because of the bloom, detectability will reset after 20 seconds. However, if the ship leaves the enemy's line of sight (e.g. by hiding behind an island), detectability will reset 2 seconds after that. If the ship remains undetected at the moment of the bloom, it will reset immediately.
Sometimes you can shoot over an island at an enemy (who is spotted by your team) and stay undetected.
Firing AA guns
Firing AA guns will increase air detectability (but not sea detectability) by an amount depending on the ship. The detectability range by air is equal to the firing range of the ship's AA guns for a period of two seconds after her AA guns cease firing. This affects detectability only in situations where enemy aircraft are within the range of your AA defenses.
AA guns can be toggled with the P key.
A ship that is on fire and not in a smoke screen will have 2 km added to its sea detectability range and 3 km to its air detectability range for as long as it is on fire. The increase does not stack with multiple fires. When a ship is in a smoke screen, fires do not change the detectability ranges.
Fire does not increase the detectability of submarines.
Upgrades and Skills
A ship's detectability range can be decreased by using certain upgrades and skills. The bonuses from each stack together multiplicatively, so a Kagero (with base sea detectability range of 6.63 km), when fully decked out for concealment, can have a sea detectability range as low as 5.37 km.
Another value is spotting range (sometimes called view range), which also doubles as a ship's render/targeting range. This is the range inside which other ships might be detected or spotted. It is indicated visually by the outer limit of the grey cone on the player's minimap in battle. No ship outside of this range can be detected by the player. Allied ships and enemy ships spotted by others that are outside of view range are not drawn on the main screen but are displayed on the minimap as outlined icons.
In general, the taller the ship the larger its view range. Battleships with their tall masts have very long view ranges (in excess of 20 km) while destroyers typically have the shortest view ranges.
Generally, view range has little impact on ship to ship detection because it is usually higher than the detectability range of the ships being spotted. The only time view range limits ship to ship detection is when the spotting ship has a lower view range than the target's detectability range, such as a destroyer attempting to spot a battleship. In these cases, the target is spotted not at its detectability range but when it enters the view range of the spotting ship.
In Update 0.11.2, the mechanics for spotting range were changed. All ships now have a minimum spotting range that depends on their tier, as well as a dynamic spotting range. The first range is a constant value that’s set regardless of the ship’s parameters. The dynamic spotting range depends on the firing range of all the ship’s weapons (main battery guns, torpedoes, secondary battery guns, and Airstrike) and always exceeds this value by 25% or 3 km. At the same time, it’s the higher value of the minimum and dynamic spotting ranges that’s always applied.
All aircraft have a view range of 15 km.
The minimum spotting range for each tier is listed below:
A ship’s firing range with modifiers and changes to the mechanics applied will always be greater than her firing range under standard conditions.
Example: North Carolina has a standard firing range of 21.1 km. The minimum spotting range for a Tier VIII battleship is 30 km. The dynamic spotting range for North Carolina is 21.1 * 1.25 = 26.4 km. Because the largest value is applied, the spotting range for North Carolina with a firing range of 21.1 km is set at 30 km.
If we equip the ship with Gun Fire Control System and Artillery Plotting Room Modification 1, our firing range will be 27 km and the dynamic spotting range value will reach 33.75 km, which will be the prevailing value for the ship’s spotting range in this case. If we also launch Spotting Aircraft in battle and increase our firing range to 32.4 km, our spotting range in battle will increase to a value that exceeds 40 km.
As the values become standardized, the standard spotting range values of certain ships may either decrease or increase.
Cyclones reduce spotting range for all ships on the map. At full effect it is limited to 8 km. Radar increases spotting range (to the same value as radar range) for its duration during cyclones but only for the ship using the radar.
In the diagram to the right, assuming that all ships are enemies to one another, the destroyer (pink) can detect the cruiser (orange) as the cruiser is within the destroyer's view range (pink dashed line) and the distance between the two ships is smaller than than the cruiser's detectability range (orange line). However, the destroyer can not detect the battleship (blue) even though the distance between them is smaller than the battleship's detectability range (blue line) because the battleship is outside of the destroyer's view range (pink dashed line).
The cruiser on the other hand can detect the battleship, as it is within the cruiser's view range and the distance between them is smaller than the battleship's detectability range, however the cruiser can not detect the destroyer even though it is within the cruiser's view range because the distance between them is larger than the DD's detectability range.
The battleship can not detect either the destroyer or the cruiser even though the battleship's view range encompasses both of them because their distance to the battleship is larger than their respective detectability range.
If the destroyer and the battleship are on the same team while the cruiser is on the opposing team, the destroyer will spot the cruiser for the battleship and it will appear as a solid icon on the battleship's minimap and be rendered in its main view. If the destroyer and the cruiser are on the same team while the battleship is on the opposing team, the cruiser will spot the battleship for the destroyer but it will only appear as an outline in the destroyer's minimap and not rendered in its main view.
By using a Smoke Generator , a surface ship may create a smoke screen. Not all ships have this consumable, but any ship may enter and use a smoke screen.
Smoke blocks line of sight (LoS). If a ship is inside a smoke screen or has smoke between it and all possible spotters, it can remain undetected even when there are enemy spotters within its normal detectability range.
Usually, the distance at which a ship covered by smoke can be spotted by ships is the assured detection range (= 2 km, see Proximity Spotting below). However, a ship firing its main battery in smoke increases its detectability range by sea, but to a lower value than without smoke (see Firing Main Guns above). If an enemy ship is present within that range the firing ship will be detected. Hence smoke is not a cloaking device. The detectability range by sea after firing main guns in smoke is higher for ships with larger main gun calibers.
An aircraft cannot detect a ship that is fully inside a smoke screen. In smoke, the detectability range by air is always 0 km, even when firing main guns or AA guns.
However, an aircraft can detect a ship that is on the other side of a smoke screen because smoke screens have a low height.
At periscope depth, submarines can only detect ships in smoke at 2 km. At surface depth, the standard rules of smoke detectability apply.
While a smoke screen obscures the vision of enemy positions, it also obscures the vision of those within the smoke. See the smoke screens article for details.
When active, Hydroacoustic Search automatically detects ships and torpedoes within a fixed radius, regardless of LoS. It detects submarines at maximum depth at a range of 2 km.
When active, Surveillance Radar automatically detects ships within a fixed radius, even those otherwise hidden by LoS. It does not detect torpedoes. It detects submarines only at surface depth.
Radar has a longer range than Hydroacoustic Search but is active for a shorter period.
The Hydrophone consumable on submarines highlights (but does not detect) enemy ships' positions in the game world and updates their position on the minimap, taking into account LoS. Against submarines, it will highlight their positions if they are at surface or periscope depth.
The Submarine Surveillance consumable on submarines provides the only way for submarines to detect enemy submarines at maximum depth (it also detects submarines at periscope depth). It works in a manner similar to Hydroacoustic Search and Surveillance Radar, ignoring LoS.
When a submarine is hit at periscope or maximum depth, an indicator saying "Oil System Damaged" will appear to the player. After 5 seconds, if the submarine has not repaired the fuel system by either surfacing or using Damage Control Party , it will leak fuel onto the surface periodically, allowing enemy ships to pinpoint its location. Fuel spills last for 40 seconds with no way to reduce their duration, and the countdown is constantly reset if the submarine is simultaneously on fire or flooding. Fuel spills are cleared when the submarine rises to surface depth, or if a submarine uses her Damage Control Party .
At 2 km (the assured detection range) a ship will automatically detect another regardless of LoS, making it possible for ships to be detected even if they are hiding inside a smoke screen or behind terrain. Submarines do not have proximity spotting at maximum depth.
Some ships incorporate elaborate torpedo protection schemes. However, the best protection against torpedoes is not to be hit by one in the first place. Detecting an incoming torpedo far from the ship gives the bridge crew time to maneuver to avoid it. Aware of this, torpedo designers try to make their fish as hard to spot as possible. One technique is to have the torpedo run deep — the notorious heavyweight deep water torpedo with a natural detection range of <<1km.
Unmodified ships spot torpedoes from a range based on the torpedo model from 0.7km to 2.5km.
For information about the detection range of each torpedo, visit the torpedo page.
The Torpedo Lookout System (TLS) upgrade detects torpedoes independent of model and is very effective against low-detectable torpedoes. It assures detection of all torpedoes within a base 1.8 km distance.
The Vigilance skill extends torpedo detection range 25%, with or without TLS. These are both essentially passive mechanisms.
The Hydroacoustic Search consumable, while it is active, detects torpedoes at an even greater distance. The actual range depends on the ship, varying from 2.5 to 4km.
Once a torpedo has been spotted, it remains spotted for the duration of its run.
Radio Location Commander Skill
The Radio Location skill (former name: radio position finding) displays a white marker indicating the approximate (22.5 degree sector) direction -- but not distance -- to the nearest enemy ship. That ship will be notified that it is being tracked through the appearance of a Situational Awareness icon.
Against submarines, Radio Location works if they are at surface or periscope depth, but not maximum depth.
The Watchful skill displays an indicator if a submarine is within the range of a currently active enemy Hydroacoustic Search or Surveillance Radar consumables while at periscope or maximum depth. It also works if a submarine is within the range of a currently active enemy Submarine Surveillance at surface depth.
When you are detected by an enemy there will be an icon informing you of the fact. It will also show the type of detection:
- Visual/proximity by sea
- By Hydroacoustic Search, Surveillance Radar or Submarine Surveillance (only as a submarine)
- By air
- Radio Location
If you are detected by multiple means only the highest in the list will be displayed.
Thunderstorm Fronts reduce the ship's detectability range by sea and the 20 seconds, and limit the spotting range.