Air warfare

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Air warfare consists of the deployment of air wings to Strategic Regions, where they can undertake missions targeting Production, Construction, Infrastructure, other Units, or in the case of naval and tactical bombers, naval units, ports, or convoys. Given that Air warfare is the only type that directly affects all 3 types of combat (on top of the strategic targeting), the air war is something the player must take into account when devising successful strategies.



Air wings are a group of planes forming an air unit attached to an air base. A new air wing is deployed from the air base screen. An air wing may be created only if there is sufficient service manpower and are sufficient planes.

Coast of Japan air region with an air wing with 72 fighters assigned to it. The air wing is carrying out an interception mission.
The player can see a list of all of their air wings in the Air Forces screen, which can be opened from the Air Overview button in the top right of the screen.

Air wings can be assigned to a strategic air region called "area" inside Hearts of Iron IV. An air region comprises a number of states and/or naval zones, and can cover a fairly large area, such as all of Northern France. Once assigned to an air region, one or multiple missions may be activated for each wing. A wing cannot be assigned to more than one region at once. Most air regions cover only land or only sea, although a few cover both. This may affect the type of mission that can be carried out. Above sea, naval and aerial strategic regions generally cover the same area.

The Strategic Air map mode may be used to select an air region in order to display information about it.

Once a new air wing is created, it will take several days for the planes to arrive at the airport. The wing may be assigned to an air region and given missions immediately, but it will not carry out the missions until the planes arrive.

One air wing needs to contain at least 1 and at most 1,000 planes. They must all be the same type of plane; it is not possible to mix fighters with close air support, for example. It is possible to change the size of an air wing once it is deployed by clicking on a base, then clicking on the top number on the left-hand side of each wing's row. The reinforcement level of an air wing represents the amount of planes an air wing has at full strength, and if the current number of planes is lower than the reinforcement level, new planes will be added to it as long as there are sufficient stockpiled planes of that type. If there are none, then reinforcement will take place when new planes of the correct equipment type are produced by the player's military production lines. The player can also merge two or more wings of the same type of plane located in the same base, or split a wing into two new wings, each 50% of the size of the original wing. There is also a Reorganize option that allows greater control over moving planes between two or more wings of the same type.

If an air wing is disbanded then all of the planes will return to the equipment stockpile, and are then available to be deployed to other air wings.

An air wing can have an Ace which improves the combat stats of the wing. Air wings in HOI4 do not have commanders and cannot be renamed.

Air Bases[edit]

An air base icon on the map in Kanto state in Japan, and carrier fleet based at the naval base in the same state

Air bases are state-wide buildings, which may be constructed or repaired at the Construction screen. In order to control an air base, the player must control its host province and 50% of the victory points in the host state. forumpost:23004635

If the player clicks on the air base icon the map changes to Strategic Air map mode, and the air base view opens


Each land-based air base can support up to 200 planes per base level without any penalties. The maximum air base level is 10, for a maximum of 2,000 aircraft. All types of planes may be located at these air bases, including carrier capable models.

The capacity of an air base is shared between allies. The tooltip for the air base shows the total number of planes located there (and a list of the countries with air wings and the types of planes). The air base view above shows Kanto has a total capacity of 1200 planes (level 6 base), and there are currently 253 planes located there.

If the total number of planes is 250 in a level 1 base (capacity 200), then the air wings get a -50% penalty to their mission efficiency. If the total is 300 planes then there will be a -100% penalty.

Air bases can be damaged by strategic bombing missions. Damage will reduce the capacity the base can hold without penalty, until repaired. If enough damage can be inflicted on enemy air bases to cause a large efficiency penalty, enemy air wings may be effectively grounded.

Overrunning By Enemy[edit]

If an air base is overrun by enemy divisions by taking control over the state the air base is in, then the air wings will automatically redeploy to another air base under friendly control. If the new air base is within range, then they will continue to operate the same missions. Their mission efficiency will be adjusted accordingly. If the mission is no longer within range, then the planes will complete any current combat mission they are engaged in, then will go into Standby at the new air base. The player or AI can then give them a new mission.

Carrier Fleets[edit]

A fleet with aircraft carriers can also operate as a floating air base. Only carrier capable models may be based on aircraft carriers. The maximum amount of planes allowed on an aircraft carrier fleet without any penalty is determined by the deck size of the carrier(s). This is much smaller than bases on land - ranging from a capacity of 45 (1922 base model CV) to 85 (1944 base model CV), and up to 31 higher with +5 deck size variants.

For a fleet to operate like an air base on land, it needs to be at anchor. If the fleet is patrolling, then the air wings are on a carrier mission. This means they can only take part in naval combat with the carrier fleet. If the fleet is anchored, then the air wings on the carrier(s) may be assigned to standard air missions covering a region, like air wings based on land. This may be very useful to provide air support for an amphibious invasion.

The carrier fleet view

The carrier fleet view is the same as the view of an air base on land, except in that, it lists each air wing under the name of the carrier(s) in the fleet. In this case, the two air wings are located on the carrier Ryujo in the fleet called 1 Koku Sentai. The wings are in Standby, because the fleet is at anchor in the naval base. These wings can then be assigned standard air missions in an air region.


Each Air Wing may be assigned to a single air region, where it can perform the possible missions for its type. With the wing selected at its air base, right clicking on an air region in range assigns it to conduct missions in that region. Then left clicking shows assigned wings and conditions in that region.

The air wing view shows the name of the air region that the air base is located in by default, and the distance to that region, which will be 0 km. If the player selects another region, then the name changes, and the distance to that region is shown. If the planes in an air wing have insufficient range to reach that region, then they will be hatched red. The player will not be able to assign them to the region. If they can reach the region, but have insufficient range to cover it all, then they will be hatched yellow to warn the player that there will be a mission efficiency penalty if they assign them to that region.

Each wing present may be given an available mission. Pressing F3 will display the Air Region Map Mode. If the player's country (or faction) has air superiority in a region, it will be tinted green. Conversely, if the enemy has air superiority in a region it will be tinted red. Contested air regions are tinted amber.

The air coverage percentage for planes which don't have sufficient range to cover the whole area of a region, is available from the air region view. An icon for each wing shows:

  • Green if Mission Efficiency is 100%, which means that air coverage must be 100%
  • Amber if Mission Efficiency is less than 100%, but over 50%
  • Red if Mission Efficiency is less than 50%

The Mission Efficiency can be affected by air base capacity and weather penalties. The tooltip for an amber or red icon will confirm if the wing is unable to cover the whole region.

The fighter wing from Kanto is assigned to the Home Islands region. Kanto is within that region (0 km range from the base). The range for the planes is 570km, which is sufficient only to cover 60% of the region, so there is a -40% penalty to Mission Efficiency. The tactical bombers have a range of 1000km which can cover the whole region, and they get no penalty.

The lower the Mission Efficiency, the less successful the mission is likely to be, the player's air wings will do less damage to their targets and are more likely to take damage, and may be shot down by enemy aircraft and AA fire. Choosing an alternative mission or sending more planes may be considered, but the most important factor is the range from the region, and therefore the location of the air base that is used. All wings with early models of light frame planes (fighters, CAS and naval bombers) will have poor coverage if they are based outside of the region they are operating in, unless their base is very close to the region border.

If the player does not control any bases within a region that they are attacking, then they are at a considerable disadvantage to their enemies, who do have control. The player might:

  • Choose tactical bombers to carry out close air support missions, instead of CAS, and use heavy fighters because of their longer range.
  • Try to capture an enemy air base as quickly as possible, so that the player can redeploy some fighters and CAS there. It might even be worthwhile if the player captures a state without an air base to build their own level 1 base there as quickly as possible. That will allow them to redeploy wings with up to 200 planes to be located within the region.
  • Use strategic bombers to bomb enemy buildings, including air bases. This might cause enough damage to their air bases to "even the odds" by reducing enemy Mission Efficiency. But this may only work if their air bases are already close to full capacity.
  • Using carrier fleets might also be very useful if the region has a coast where the player can (safely) anchor the fleet. Especially if the attack on the region is being carried out by a naval invasion. The carrier fleet can carry out the multiple roles of protecting the transport convoys, and providing shore bombardment.
  • Abandon trying to compete for Air Superiority with the player's fighters, and rely only on interception missions. Fighters on interception missions only take off and attack bomber wings if they detect a target. This causes lower losses of the player's fighters. It will give the player's enemy the Air Superiority bonus in combat however.
The nearest Japan air base to China is Liaotung, which is 747km from the North China region. The CAS wing there only has a 700km range and suffers a -70% efficiency penalty, because the CAS can only cover 30% of the region. Japan owns two states within the region, including East Hebei. Building a new air base there before Marco Polo means the CAS can cover 84% of North China region, and receive only a 16% penalty.

The Air missions ordered will be conducted regardless of weather, but bad weather reduces detection and efficiency and increases the risk of an accident at take-off and landing. The effects increase with weather severity, with sandstorms and blizzards being particularly bad. It may be advisable to put air wings on standby during such conditions.

Type of Planes Missions Available
Fighter Air Superiority, Interception
Heavy Fighter Air Superiority, Interception
Naval Bomber Naval Strike, Port Strike
Tactical Bomber Close Air Support, Strategic Bombing, Port Strike
Strategic Bomber Strategic Bombing
Close Air Support Close Air Support, Naval Strike, Port Strike
Transport None, but required for paratrooper missions
  • Close Air Support: Directly attacks enemy land units that are engaged in combat. (Tactical bombers can also attack enemy ships engaged in combat.)
  • Air Superiority: prioritizes attacking enemy fighters on their own air superiority missions, but also can escort the player's bombers and intercept enemy ones. If air superiority is attained, a bonus to land units in the region will be given.
  • Interception: attacks enemy bombers. Heavy Fighter range and survivability makes them suitable for bomber interception and escort. Interception missions never attack enemy fighters.
  • Naval Strike: Attacks enemy ships at sea.
  • Port Strike: Attacks enemy ships in port at a naval base. It does not attack the port facilities, the naval base can be damaged only by strategic bombing. Requires air superiority in the air region the port lies in. (This means on land).
  • Strategic Bombing: Attacks enemy constructions, including factories, infrastructure, AA, naval bases and air bases etc. If air bases are bombed, then there is a chance to destroy enemy planes based there.
  • Kamikaze Strike: Special mission unlocked with the Japanese national focus or with Ideological Fanaticism from the generic national focus tree. Prioritizes inflicting maximum damage against sea targets, at the cost of aircraft.

Transport planes have no missions. They are required to execute paradrop plans. Unlike in HOI3, they are not used to drop supplies in version 1.3. This feature may be added in later versions.

Assigning more than one mission to an air wing will not result in simultaneous execution of all these missions. For example, if the Close Air Support and Strategic Bombing missions are activated for Tactical Bombers, they will usually perform the Strategic Bombing first, until there are no more active constructions in the area. Fighters with both air superiority and interception missions probably only ever carry out air superiority. It is more efficient to have two wings each ordered to execute one of two mission types than have both of them ordered to execute both mission types.

Naval bases are located within provinces on land. Port strikes can therefore only take place in a region which covers land. The port strike mission will be ignored if it is given to a wing operating in an all-sea region, like the Yellow Sea. Some regions mainly cover the sea, but they may also include some islands with naval bases, like East China Sea which includes Taiwan. The opposite is also the case - a naval strike can only target fleets which are at sea, so such a mission would be ignored if given to a wing which is assigned to an all-land region like Northern China. Finally, close air support missions and strategic bombing would be ignored if given to a wing in an all-sea region. In some parts of the world the player has to be careful to check which region a naval base is located in, otherwise they could be giving wings missions that will be ignored, as the interface does not warn them if that is the case.

Mission Schedule, Rest, and Day/Night cycle[edit]

Missions take 7 hours in the air and a plane can only do two missions in a row. After that, it must rest at the air base for at least 4 hours before it can be sent into combat again. Its mission schedule depends on whether it is set to Day missions only, Night missions only, or Day & Night missions. Day is from 09:00 to 00.00 on the game clock. Night is from 01:00 to 08:00. At night, it is 20% harder to detect planes and bombing has -50% efficiency but air combat is otherwise unaffected.

  • Day: Enters first mission at 09:00 and leaves second mission at 23:00, then rests until its next day mission.
  • Night: Enters combat at 01:00 and leaves at 08:00, then rests until its next night mission.
  • Day & Night: Enters a 19 hour cycle of performing two missions, resting, and repeating until ordered to stop.

Air combat (fighters)[edit]

This section exclusively develops on the topic of air combat, aircraft versus aircraft. Using information available in the defines.lua file, it's possible to speculate that air combat simulation approximately follows these steps:

  • Detection: If enemy airplanes are not detected in the region, interceptors (defending fighters on interception mission) will not take off.
  • Target acquisition: This phase will determine what's the maximum possible damage that air wings can do and also which type of aircraft will receive the damage depending if it's an air superiority or intercept mission.
  • Combat simulation: This phase will determine how much damage is done or received in each round of combat.
  • Rest: The land-based air wings, or CV-based planes taking place in air combat, all rest for 4 hours after a mission, then they can be sent on their mission again. CV-based planes must rest for 6 hours between strikes within naval combat.


The following variables, or defines, are known in order to resolve the detection phase:

  • Base detection chance from aircraft: 5%. This value can be increased through doctrines that provide Interception detection or Fighter detection.
  • Detection chance from effective aircraft: 2,000 planes are required in the air region for the base detection chance to apply, interpolated otherwise.
  • Detection chance without search mission: -50%. Planes which don't have a search mission (such as bombers), only count at 50% towards the effective aircraft total.

Example: If the player has 200 fighters on an air superiority mission these will count 200 towards the effective aircraft total. If the player has 100 CAS on port strike, they will only count 50 towards the total. This will give an overall amount of 250 effective aircraft. If the player's doctrines have not increased the base detection chance (5%), this will produce a detection chance from the 250 effective planes in the region of 0.625%

  • Detection chance from radars: 25%. Radar stations have a range of 140 to 1565km (20 to 220 pixels) from the center of the State they are built in. The range is interpolated based on the radar station level (1-6). The area covered by the radar station will be shown on the map in air mode, coloured a darker blue than normal. The bonus is interpolated from the percentage of the provinces in the air region which are covered by radar. The player can use a single radar station in a state with a central position (most regions can be completely covered by a level 2 or 3 radar), or radar stations in more than one state. If the areas covered by multiple radar stations overlap the affected provinces will stack, but the total bonus will never go above 25%. Radar stations based in an another region may also count, as long as their range covers part of the player's region. So radar stations on land can cover the naval zones in a nearby naval region.
  • Detection chance during the night: -20%. This value essentially means that interceptors can't detect aircraft at night without a number of air doctrines and/or good radar coverage.
  • Detection chance from occupied provinces: 10%. This bonus is 10% for occupying the whole state. If the occupation is split between two or more countries, then the 10% bonus is divided depending on the number of provinces each of them occupies out of the total in the state. So if the player occupies 150 provinces in a state with 200 provinces they will get 7.5% detection chance. If the player's enemy occupies the other 50 provinces they will get 2.5% detection chance. This bonus applies to detection throughout the air region.

Once the detection chance is established, then it gets modified by efficiency modifiers which serve to determine how many aircraft are detected.

  • Base detection efficiency: 10%. Once something is detected, the base detection efficiency means that 10% of all enemy aircraft are "found" or located.
  • Radar detection efficiency: 70%. Radar coverage will allow an extra 70% of all enemy aircraft to be "found" or located.
  • Random factor: 10%. The defines add a 10% random factor to detection efficiency. It's not clear whether the factor can have a negative value or if it's binary (0% or 10%).

Target acquisition[edit]

Once aircraft are detected and the number of detected aircraft is determined, it's necessary to find out who will receive the damage resulting from the combat simulation. In the case of an air superiority fight, the answer is straightforward: the enemy fighters.

  • Base number of attack passes: 10%. This value multiplied by the attack value of an air wing will give the base number of passes each aircraft can do in single combat. An "attack pass" gives a chance to do damage against an aircraft. Note that, just like army divisions, an air wing with different models of aircraft will average out their value for the entire air wing so that any one fighter will be indistinguishable from any other fighter in the air wing. But the combat simulation is done at the single aircraft level.

In the case of interceptors, they possibly have multiple kinds of targets: escort fighters or the bombers themselves. The interceptors want to intercept or shoot down enemy bombers as much as possible and a few variables will increase or decrease their chances to roll attack damage on the bombers instead of escort fighters.

  • Base chance to attack bombers directly: 25%. Interceptors have a base 25% chance of "bypassing" the escort fighters and to attempt to inflict damage directly to bombers. (in the defines, this is called the "Combat escort pass chance")
  • Multiplier to chance to attack bombers directly: 25%. When there's a combat statistics difference (for speed or agility) between the interceptors and the escort fighters, the chance to "bypass" the escort fighters is modified. 25% of the statistical difference is used to add or substract to the base chance to attack bombers directly.
  • Maximum chance to attack bombers directly: 95%. Regardless of how better the interceptors are, they will never have more than 95% chance to "bypass" the escort fighters.

Now, the number of aircraft in the simulation will almost never be the same. The numerical advantage on one side provides a chance to result in more 2vs1 single combat simulations, instead of the default 1vs1.

  • Gang chance from combat aircraft advantage: 40%. It appears this value applies on the difference in number of aircraft and the result gives the number of 2vs1 combat situations.
  • Combat stack limit: 2. This value determines how big a gang situation can occur: 2vs1. This also implies there's no advantage in having more than a 2:1 air superiority for air combat purposes.

Also of note, the defines have a modifier to the number of passes that can be done against bombers or against air superiority missions (in single, 1 versus 1, fight). At the time of writing this, the modifier is set to "1", meaning the number of passes is not affected, but this could change in the future.

Combat resolution[edit]

  • Chance for pass without event: 60%. For each "attack pass" that an aircraft does, there's a 60% chance it will result in an "uneventful pass", no damage done, but also no damage received.
  • Factor of the effect of higher speed on attack chance: +25%. This factor applies only in air superiority vs air superiority combat only. During those air combat, the speed advantage of the fastest fighter wing will give that wing a +25% chance to attack first.

For the 40% of passes that are not uneventful, there's still a chance the pass doesn't result in a successful hit for the attacker:

  • Base chance to hit for each pass: 60%. A hit means that the target aircraft receives 1 point of damage. The cumulative damage will need to reach the air defense value before the target is shot down.

Here's an average (incomplete) result for 1vs1 scenarios: each air wing has an attack value of 16. This means that each plane will do 1.6 attack passes in each round (on average) and 0.96 of these will be uneventful (on average). One of the two planes will attack first and 0.64 of its attack passes will give it a 60% chance to score a success (it's possible that the same define was entered twice in defines.lua, but with 2 differents strings). Out of those 0.64 eventful attack passes, 0.384 (on average) would result in a success and then the other fighter in combat would roll for it's attack value. Rinse and repeat until one of the fighters is shot down or the combat ends.

This base chance to hit for each pass is modified depending on different situations:

  • Maximum bonus to hit chance due to better stats: +20%. A plane with a "combat statistics advantage" can obtain up to 20% to its chance to hit for each pass it does.
  • Bonus to hit chance from 2vs1 situations: +18%. When a single combat simulation is done in a 2vs1 scenario, the "ganging" airplanes receive an 18% bonus to their chance to hit for each pass they do.
  • Maximum damage reduction from higher agility: +20%. Higher agility than the attacking aircraft will help the target reduce the damage it takes.

Also important to note that there is a maximum number of air wings allowed in a combat simulation: 6. With each air wing currently able to support up to 1,000 aircraft, this means there's a theoretical limit to the number of aircraft that can enter a combat simulation: 1,000. More importantly, a low number of aircraft in each air wing will not improve the situation in any way past 8 air wings. It's not clear at the moment if the limit of 8 air wings is for each side or the total for both sides.

Calculation of airplane stats difference[edit]

During the combat simulation, the difference in value of Agility and Speed statistics will impact a number of variable such as the chance to bypass escort fighters or the chance to hit an enemy fighter. Note that aircraft variants created in the production interface by using Air Combat Experience can change statistics and therefore combat effectiveness in powerful ways. (see the guide linked below)

  • Speed difference multiplier: 25%. A speed difference between two aircraft will provide a "combat statistics advantage" equal to 25% of the speed difference.
  • Agility difference multiplier: 100%. An agility difference between two aircraft will provide a "combat statistics advantage" equal to 100% of the agility difference.

For example, without any variants, a 1940 fighter will have an advantage of 150km/h in speed and 15 points of agility over a 1936 fighter. This will result in a (150*0.25%)+(15*100%) = 52.5 combat statistics advantage for the 1940 fighter.

  • Maximum agility factor: 3. This is unclear, but it appears that for the purpose of damage reduction, the aircraft with the higher agility will not get any marginal statistical advantage if its agility is 3 times higher than the lower agility. This is effectively a cap on damage reduction.

Known unknowns[edit]

  • One define in particular mentions a modifier on who attacks first, but the base value or the value for each mission is unknown.
  • The air combat simulation seems to resolve combat on a 1vs1 level, or possibly a 2vs1 scenario, but it's unknown how many rounds of combat there are.
  • Some defines are no longer in use in the simulation, but it's impossible to know which. Therefore, any of the information above may be inaccurate.

Air superiority[edit]

Every 50 points of air superiority advantage in a strategic region gives a +1% air support malus to enemy land combat. For this reason it is advised to hold air superiority as much as possible.


Air combat has a chance of generating aces. An air wing may be assigned up to one ace only.

Skill Level Chance Fighter Ace Strategic Bomber Ace CAS, TAC, or Naval Ace
"Good" 0.9
  • +3% Air Attack
  • +3% Speed
  • +5% Agility
  • +5% Bomb Targeting
  • +3% Range
  • +5% Naval Strike Targeting
  • +3% Ground Bomb Targeting
  • +5% Agility
"Unique" 0.4
  • +6% Air Attack
  • +5% Speed
  • +10% Agility
  • +10% Bomb Targeting
  • +6% Range
  • +10% Naval Strike Targeting
  • +5% Ground Bomb Targeting
  • +10% Agility
"Genius" 0.05
  • +10% Air Attack
  • +8% Speed
  • +15% Agility
  • +15% Bomb Targeting
  • +10% Range
  • +15% Naval Strike Targeting
  • +8% Ground Bomb Targeting
  • +15% Agility

The effects are scaled inversely by the size of the wing relative to 100 planes, to a maximum of 10x at 10 planes.

Close Air Support[edit]

Whenever a battle takes place on the ground, an air-wing assigned to the CAS mission can join and do damage to the enemy troops. Multiple air-wings on the CAS mission can join; however, one air wing cannot split up and join two or more battles. The number of planes from the air-wing joining the battle is dependent on the enemy troop frontage. The number of planes able to join the land battle is 3 times the used enemy frontage.

The allowed CAS frontage is adjusted by the type of terrain in the province where the land battle takes place.

The following factors apply:

  • Forest: -10%
  • Urban: -50%
  • Hills: -5%
  • Desert: -0%
  • Plains: -0%
  • Mountains: -10%
  • Marsh: -0%


  • One forest land battle takes place in the air region. The enemy frontage is 20 which allows 3x20*0.9 = 54 planes on the CAS mission to join the battle. CAS wings will join the battle to fill up to 54 planes.
  • Two land battles take place in the air region. The first battle is in a forest and the enemy frontage is 20 which allows 3x20*0.9 = 54 planes to join in. However, each of the two air wings is in stacks of 50 planes. If they both join the battle, the 2nd air-wing wastes 46 planes that cannot join another battle.

In the defines.lua file COMBAT_MAX_WINGS_AT_GROUND_ATTACK is set to 30, which suggests that up to 30 CAS air wings can be active at the same time in an air region. It is unclear if this affects the maximum air wings limit of 6 for fighters.

How CAS damage is calculated is currently unknown.

CAS planes may also contribute to air superiority in an air region depending on their air superiority stat, for as long as an CAS wing is active.

Strategic Bombing[edit]

Strategic bombing damage is about 120 damage per attack cycle for ~0.3 buildings destroyed. This damage appears to be distributed evenly among all the buildings (forts, industry etc.) in the air region without regard to the number of air wings presents.

As bombers generally are vulnerable to fighters, it is advised to bomb only in regions with more than 50% air superiority.

Naval Bombing[edit]

(This information needs verification.)

  • Naval bombers and close air support airplanes can attack enemy fleets that are in the open seas (not in a port). This attack is known as a "naval strike."
  • Tactical bombers can attack enemy fleets engaged in combat if set to perform "close air support" on a sea zone.
  • Naval bombers, close air support airplanes, and tactical bombers can attack enemy fleets that are moored in an enemy port. This attack is called a "port strike."
  • The success of naval bombing missions is improved by bonuses from both the naval and air doctrine trees.

Naval Strike[edit]

Airplanes have a base 4% to detect or find an enemy fleet. This detection percentage is modified by other variables.

Once an enemy fleet is discovered, a randomly assigned ratio of planes to fleet frontage is determined. Fleet frontage is calculated from the total hit points (HP or health) of the enemy fleet divided by 20. Typically, the ratio of attacking planes to fleet frontage is 1:1. Each plane assigned to the attack rolls to hit a target. If the plane hits, it does damage equal to the plane's naval attack (naval damage) value. In a fleet with multiple ships, the target is randomly selected (note: increased ship's surface visibility may increase its chance to be selected as a target...more visible targets are more often struck. This needs to be verified). For example, if a NAV1 hits a heavy cruiser 1, the NAV1 will do 1.5 points of damage. That is, the battleship will lose 1.5 hit points out of its total of 150 hit points.

Port Strike[edit]

Port strikes may be performed by naval bombers, tactical bombers as well as close air support. Port strikes are an effective way to thin out the enemy navy but performing a port strike requires air superiority in the continental strategic region the port lies in.

Naval Air Bonuses[edit]

Doctrine Type of Doctrine Name of doctrine Bonus Comments
Naval Doctrine Trade Interdiction
  • +10% Naval Targeting
  • +10% Naval Targeting
Modifies our planes' ability to target their objectives when executing naval strikes.
Naval Doctrine Base Strike Base StrikeBase Strike +50% Port Strike Each successful hit does 50% more damage to ships docked at a port [needs verification]
Naval Doctrine Base Strike
  • +10% Naval Targeting
  • +10% Naval Targeting
  • +20% Naval Targeting
  • Modifies our planes' ability to target their objectives when executing naval strikes.
  • One interpretation is that naval targeting is a per cent increase in the chance of a naval bomber hitting a ship (40% is the base chance of a plane to hit a ship)
Air Doctrine
  • Battlefield Support
  • Operational Integrity
+10% Naval mission efficiency
  • Improved tactics for planes doing naval bombing or port strikes resulting in increased ability.
  • One interpretation is that Mission efficiency is a multiplicative on Attack + Defense of the naval bomber. This grants more chances to hit ships and avoid AA fire or enemy planes.
Air Doctrine Strategic Destruction Naval Strike TacticsNaval Strike Tactics +15% Naval mission efficiency Improved tactics for planes doing naval bombing or port strikes resulting in increased ability.

The naval doctrines "Trade Interdiction" and "Base Strike" give both land or carrier based air craft (naval bombers, close air support, and tactical bombers) "naval targeting" bonuses.

The Naval Doctrine Trade Interdiction gives a +20% total naval targeting bonus.

The Naval Doctrine Base Strike gives both a +40% total naval targeting bonus and a +50% port strike bonus. The Naval Doctrine Base Strike provides the most naval air attack bonuses of all the doctrines. Base Strike is the choice for nations focusing on a naval bomber build (e.g. Canada).

The Air Doctrines Battlefield Support and Operational Integrity give both land or carrier based air craft (naval bombers, close air support, and tactical bombers) a +10% "Naval Mission Efficiency" bonus. This +10% naval mission efficiency bonus is earned upon completion of the Torpedo Strike Torpedo Tactics found in both "Battlefield Support" and "Operational Integrity." The in-game tooltip definition of Naval Mission Efficiency is "improved tactics for planes doing naval bombing or port strikes resulting in increased ability." The significance of Naval Mission Efficiency is that it allows 10% more naval bombers, close air support, and tactical bombers to conduct a naval strike or port attack. Naval Mission Efficiency helps counterbalance the decreased percentages of aircraft available due to bad weather or longer distances.


Air Mechanics/Combat/Mission "Quick" Guide