22. NAVAL INTERCEPTION AND COMBAT
22.1 NAVAL INTERCEPTION
22.2 RESOLVING NAVAL INTERCEPTIONS
22.3 NAVAL COMBAT
22.4 NAVAL COMBAT SEGMENTS
22.5 FLEET COMBAT
22.6 WITHDRAWAL FROM NAVAL COMBAT
22.7 ADDITIONAL ROUNDS OF NAVAL COMBAT
22.8 EFFECTS OF NAVAL COMBAT
22.9 SUBMARINE ATTACKS

22.1 NAVAL INTERCEPTION:
22.11 GENERAL: When a player undertakes any naval activity, the opposing player may intercept with any of his own uncommitted, uninverted naval units within interception range. A naval unit is considered to be uncommitted if it is not engaged in another naval activity already announced during the same segment of the player turn. Interception is subject to the qualifications set out below:
A. IMMUNITY FROM INTERCEPTION: The following naval units may not be intercepted:
B. PROHIBITED FROM INTERCEPTING: Naval units based in the following locations may not intercept:
C. RAIDERS: Raiders may be intercepted on the mapboard while moving to the Atlantic, Pacific or Indian Ocean SW boxes (21.533D); raiders which reach a SW box may be opposed in accordance with 21.534.
D. OFFENSIVE PATROLS: Naval units on offensive patrol may not counter-intercept, but may support intercepted friendly naval units (21.4182).
22.111 NO BRP EXPENDITURE REQUIRED: Interceptions and counter-interceptions do not require any expenditure of BRPs.
22.112 Interceptions may not be attempted unless the countries involved are already at war; a player may not declare war during his opponent’s turn in order to intercept.
22.113 If the Western Allies and Russia both wish to intercept the same enemy naval activity, the Western Allies prevail.
22.114 Each submarine intercepts separately (22.915).
22.115 Naval units may be intercepted as they return to port.
22.116 Naval units which unsuccessfully attempted interceptions during a phase may not attempt to intercept returning naval units during that same phase (22.27).
22.12 SELECTING AN INTERCEPTION HEX: Once a player (the “attacker”) indicates a naval activity, the opposing player (the “defender”) may require the attacker to indicate the exact path of hexes taken by his naval units. The defender then may select one hex in which he will intercept the attacker’s naval activity.
A. If the attacker's naval units begin their activity in port, the defender may select the hex in which the attacker’s naval units are based (since they enter the water portion of that hex as soon as they leave port), the destination hex or any hex in between.
B. If the attacker's naval units are already at sea (moving from their patrol hex or returning to base), the defender may select any new hex the attacker’s naval units enter, including the destination hex. The defender may not select the hex in which the naval units begin their new activity, as the defender has already had a chance to intercept in that hex.
22.13 ONLY ONE INTERCEPTION HEX PERMITTED: A naval force may be intercepted in only one hex along its route, subject to the following exceptions:
A. STRAITS: Naval activities which pass through straits (21.211) and the Kiel canal are treated as distinct naval activities for interception purposes on each side of the strait, and are thus subject to a single interception in different hexes on each side of the strait.
B. DIFFERENT NAVAL ACTIVITIES: Each time a naval force attempts to carry out a distinct naval activity, it may be intercepted, even if some or all of that force has been intercepted earlier in the same turn while carrying out a different naval activity.
C. COMBINING NAVAL FORCES:
D. SPLITTING NAVAL FORCES: A naval force which splits from another naval force during the course of an activity is subject to naval interception even if the combined naval force was intercepted, provided the new naval force enters a different sea hex from its parent naval force.
E. SUBMARINES: Submarines may intercept in a different hex from other naval units (22.915).
F. RETURNING NAVAL FORCES: A naval force may be intercepted a second time once it has completed or aborted its naval activity.
G. DISPLACED NAVAL UNITS: A displaced (21.23) or escaping (23.462) naval force may be intercepted.

EXAMPLE: Japanese TFs sail independently from Manila, Okinawa and Tokyo, rendezvous south of Okinawa and proceed on their mission. The Americans could intercept each of the three groups prior to their rendezvous, and intercept once afterwards. Had the Japanese combined their TFs by sailing the Manila TF to Okinawa, then both TFs to Tokyo, then all three TFs on their mission, the Americans could have intercepted the Manila TF, the combined Manila and Okinawa TFs, and all three TFs, but the Okinawa and Tokyo TFs could not have been intercepted separately.

22.131 INTERCEPTION IN THE ACTIVITY HEX: If interception occurs in an activity hex, the interception is resolved before the naval force completes its activity.
22.132 AIR ATTACKS:
A. Air attacks on naval activities are distinct from naval interceptions and may be made in any hex or hexes along the route of the naval activity (23.7), including a hex where naval interception occurs and hexes along the path taken by naval units returning to port.
B. If air attacks and naval interception occur in the same hex, the attacking air units participate in the resulting naval combat and may not attack the intercepted activity outside of naval combat.
22.14 INTERCEPTION MECHANICS:
A. INTERCEPTIONS OF DIFFERENT ENEMY ACTIVITIES PERMITTED: Naval units based in the same port may intercept different enemy naval targets, whether or not they are part of a TF, although each naval unit may intercept only one enemy naval target per phase.
B. TFs INTERCEPT SEPARATELY: Each TF, including those in the same port, intercepts separately, even against the same enemy target. TFs may be reconstituted immediately before intercepting and counter-intercepting. This may result in the formation of new TFs so that more TFs intercept the same enemy target.
C. NAVAL UNITS WHICH ARE NOT IN A TF: Up to nine non-TF naval factors in a given port may intercept each enemy target, regardless of the size of the enemy target. A TF and naval units which are not in a TF may both intercept from the same port.
D. HOLDING BACK NAVAL UNITS: Naval units may be held back from interception for any purpose.
E. ONE INTERCEPTION HEX ONLY: If naval units from more than one base intercept the same enemy target, they must select a common interception hex (22.13).
F. INTERCEPTION BY DEFENSIVE PATROLS: Naval units on defensive patrol intercept in the same manner as naval units in port.
22.141 Successful naval interception results in naval combat between the intercepting naval force and the intercepted naval force, as well as all other enemy naval units passing through the interception hex, including submarines, subject to the following exceptions:
A. NAVAL ACTIVITIES WITH DISTINCT PATHS: Naval activities which cross paths in a single hex, other than a common hex of origin or a common destination hex, are considered to have passed through the hex at different times and are intercepted separately.
B. SEA SUPPLY: Sea supply lines to different supply zones are intercepted separately.
C. RAIDERS: Raiding groups moving to or from an SW box are intercepted separately.
D. SEA ESCORTS AND NRs: All sea escorts and NRs are intercepted separately unless the moving player has elected to combine sea escorts (28.32A) or NRs (28.32B) to the same destination. Combined sea escorts and NRs are intercepted together.
E. NON-COOPERATION: British and French naval forces while Anglo-French cooperation restrictions are in effect (53.253).

While sea supply and NRs to different destinations may not support one another (22.141B, C), because their range is unlimited (21.3612), sea transports and seaborne invasions may support one another except in their target hex, as 21.321 prohibits naval forces conducting a sea transport or seaborne invasion from entering the target hex of another sea transport or seaborne invasion.

22.15 CONTEMPORANEOUS NAVAL ACTIVITES: The moving player must, at each stage of his player turn, announce all the contemporaneous naval activities he wishes to conduct before the defender decides whether and where to intercept:
A. During the movement phase the moving player must indicate all patrols, naval base changes and SW box redeployments before the defender makes any interception decisions; during the combat phase the moving player must announce all naval missions he will undertake, including the destination of each mission and which ground units, if any, are aboard his fleets, before the defender makes any interception decisions.
B. Sea supply, raiders and NRs are contemporaneous and are announced by the moving player simultaneously, although they may be made separately and carried out sequentially.
C. Naval units return to base contemporaneously once all contemporaneous activities are completed (EXCEPTION: Patrolling naval units may remain in their patrol hex until other friendly naval forces have returned to port, in order to assist those naval forces if they are intercepted).
D. Naval units which abort an activity, withdraw from naval combat or are displaced during the opposing turn return to base immediately.
22.16 COUNTER-INTERCEPTIONS: The attacker may counter-intercept the defender's intercepting naval units in the same manner as interceptions.
22.161 MECHANICS: Counter-interception takes place before naval combat arising out of the defender’s original interceptions is resolved. Counter-interceptions are carried out in the same manner as interceptions. The manner in which naval combat is resolved depends on the location of the counter-interception hex:
A. INTERCEPTION HEXES: If an intercepting force is counter-intercepted in the same hex as it intercepted the moving player’s naval activity, a single naval battle is resolved in the interception hex between all naval forces in that hex. Other intercepting and counter-intercepting naval forces which did not reach the interception hex in their first attempt may also join in subsequent rounds of the naval combat (22.24B).
B. NON-INTERCEPTION HEXES: If an intercepting naval force is counter-intercepted in a hex other than its interception hex, naval combat between the intercepting and counter-intercepting naval forces is first resolved in the counter-interception hex, without the participation of the naval force which was originally intercepted, to determine whether the intercepting naval force is able to complete its interception. If the intercepting naval force defeats the counter-intercepting naval force, it may either continue to the interception hex and engage in naval combat with the intercepted naval force or abort the interception and return to port, at the owning player’s option.
22.162 COUNTER-INTERCEPTION OF MORE THAN ONE INTERCEPTING TF: If two or more intercepting TFs traveling along the same path, whether or not they started from the same port, are counter-intercepted together (22.141) before the interception hex (22.161B), a single naval battle is resolved as set out in 22.252.
22.163 OFFENSIVE PATROL SUPPORT FOR FRIENDLY NAVAL ACTIVITIES: Naval units on offensive patrols, including submarines, do not roll dice to counter-intercept. Instead:
A. Patrolling naval forces may only counter-intercept in the hex in which the intercepting enemy naval forces intercepted the original naval activity.
B. If the interception hex is within three hexes of its patrol hex, the patrolling naval force moves to the interception hex and participates in the first round of naval combat.
C. If the patrol hex is more than three hexes from the interception hex, the patrolling force does not participate in the first round of naval combat; its participation is deferred by one round for every additional four (European) or two (Pacific) hexes it is from the interception hex. In Europe: patrol hex within 3 hexes: round one; 4-7 hexes: round two; 8-11 hexes: round three, and so on; in the Pacific: patrol hex within 3 hexes: round one; 4-5 hexes: round two; 6-7 hexes: round three, and so on.
D. Patrolling naval forces which participate in the naval combat between a friendly naval force and an intercepting naval force adopt its mission once any naval combat is resolved, provided they are permitted to do so (21.4182B).
E. If naval combat ends before a patrolling force enters naval combat between a friendly naval force and an intercepting naval force, the patrolling force returns to its patrol hex and may be used later in the player turn (21.4182C).
22.164 SEQUENCE OF INTERCEPTION AND COUNTER-INTERCEPTION ATTEMPTS: Where both players are intercepting and counter-intercepting naval forces, this sequence is followed:
A. INTERCEPTIONS: The defender announces all naval interception attempts (EXCEPTIONS: Interceptions of patrols, which may occur while a patrol is en route to its patrol hex - 21.416; interceptions of returning naval units, which occur once the activity is completed - 22.18), then makes his naval interception dice rolls.
B. COUNTER-INTERCEPTIONS: All naval counter-interceptions of interception attempts are then announced and resolved, before any naval combat resulting from successful interceptions is resolved.
C. COUNTER-COUNTER-INTERCEPTIONS: All naval counter-counter-interceptions are then announced and resolved, before any naval combat resulting from successful counter-interceptions is resolved.
22.17 COUNTER-COUNTER-INTERCEPTIONS: No further levels of interceptions beyond counter-counter-interceptions are permitted.

All good things must come to an end. The moving player may conduct naval activities and counter-intercept; the defender may intercept the moving player’s naval activities and (in rare cases) counter-counter-intercept the moving player’s counter-interceptions. Counter-counter-counter interceptions are prohibited, both because they almost never arise and because the word is too hard to say.

22.18 INTERCEPTION OF RETURNING NAVAL UNITS: Naval forces may be intercepted as they return to port.
A. Interceptions of returning naval units are not announced until the naval units in question attempt to return to port.
B. Naval forces returning to port may first be intercepted when they enter a sea hex adjacent to their activity hex.
C. Naval units returning to port may, subject to range restrictions (21.33), combine with other friendly naval units for mutual protection, in the same manner as naval units engaged in a naval activity (22.141).
D. If a naval force divides into two or more naval forces as it returns to port, the newly created naval forces are subject to interception even if the original force was also intercepted.
E. Patrolling naval units may defer their return to port in order to protect naval forces which performed missions as they return to port.
F. The interception modifiers for naval units returning to port are recalculated. No additional dice are rolled to intercept a returning naval force which was spotted by air units while moving to its activity hex
22.19 COMBINED AIR AND NAVAL INTERCEPTION: The moving player dictates the order in which air attacks and naval interceptions of concurrent naval activities are resolved, the intercepting player dictates the order in which air attacks and naval counter-interceptions of concurrent naval interceptions are resolved, and so on.
A. When naval interception occurs, the intercepting force first sails to the interception hex, possibly undergoing air attack en route.
B. The intercepted force then moves to the interception hex, and is also subject to air attacks en route.
C. Once both forces have reached the interception hex, naval combat, including air attacks in the interception hex itself, is resolved.

22.2 RESOLVING NAVAL INTERCEPTIONS:
22.21 DICE ROLLS USED: Naval interceptions are resolved by rolling one or more dice for each intercepting naval force, calculating the total, and comparing that total to the distance to the interception hex to determine whether the intercepting naval force arrives in time for the first round of naval combat or later joins the naval battle in a subsequent round (22.23).

Naval Interception Table - 22.21

Dice

Relevant Factors

2

Activities carrying cargo (sea supply, sea transports, seaborne invasions, sea escort), shore bombardment and fast carrier missions.

2

Patrols which attempt to remain in their patrol hex for the remainder of their player turn.

2

Counter-interception in an interception hex.

1

Each TF in the intercepted force.

1

Each ground factor defending against a seaborne invasion in the interception hex. Maximum +3.

1

Each air squadron which spots the naval activity. Maximum +3.

1

Each submarine that is on patrol or uninverted in a base within three hexes of the interception hex; surface forces only. Maximum +3.

1

Codebreaking. Maximum +1.

-1

The intercepting force contains slow ships or is a submarine.

Explanation: The number of dice rolled for naval interception is determined by the total for the applicable relevant factors. If none of the factors apply, no interception may take place. In the Pacific theater, the interception result is halved (round up).

Patrols: Naval units on offensive patrol, including patrolling submarines, do not roll dice to counter-intercept. Instead they immediately support a friendly naval force within three hexes of their patrol hex; their support is deferred by one combat round for every additional four (European) or two (Pacific) hexes to the interception hex (22.163).

Counter-interceptions: Counter-interceptions and counter-counter-interceptions are resolved in the same manner as interceptions.

Maximum Range: The maximum range for naval interception is 40 (European) or 20 (Pacific) hexes.


22.22 NUMBER OF DICE ROLLED: The number of dice rolled is determined by the Naval Interception Table. The cumulative total is used. There is no limit to the number of dice that may be rolled, although maximum range for naval interception is 40 (European) or 20 (Pacific) hexes.
A. CARGO, SHORE BOMBARDMENT AND FAST CARRIER MISSIONS: Two dice are rolled if the intercepted naval force is carrying cargo (sea supply, sea transports, seaborne invasions, sea escort) and for shore bombardment and fast carrier missions. The cargo modifier also applies to the naval force’s return trip to port.
B. PATROLS: Two dice are rolled if the intercepted naval force is a patrol attempting to remain in its patrol hex for the combat phase.
C. COUNTER-INTERCEPTIONS: Two dice are rolled if the intercepted naval force is counter-intercepted or counter-counter-intercepted in the interception or counter-interception hex.
D: SIZE OF THE INTERCEPTED FORCE: One die is rolled for each TF in the intercepted naval force.
E. CONTESTED INVASIONS: One die is rolled for each ground factor defending against a seaborne invasion in the interception hex, up to a maximum of three dice.
F. AIR: One die is rolled for each land-based search AAS or NAS which spots the enemy naval force en route to or in the interception hex, up to a maximum of three dice.
G. SUBMARINE ASSISTANCE: One die is rolled by surface forces for each friendly submarine that is on patrol or uninverted in a base within three hexes of the interception hex, up to a maximum of three dice. A submarine assists interceptions by surface forces, but not submarines.
H. CODEBREAKING: One die is rolled for all naval interceptions for that player turn if the intercepting player plays more strategic cards than his opponent with respect to naval interceptions.
I. SLOW SHIPS AND SUBMARINES: One fewer die is rolled if the intercepting naval force contains slow ships or is a submarine.
22.23 SUCCESSFUL NAVAL INTERCEPTIONS: If the interception dice roll is equal to or greater than the distance in hexes from that naval force’s base to the interception hex along its previously announced path (which will usually, but not always, be the shortest distance), the interception succeeds, subject to counter-interception, and the intercepting naval force engages the intercepted naval force in the first round of naval combat.
22.24 FAILED NAVAL INTERCEPTIONS:
A. COMPLETE FAILURE: If all initial interception attempts of a particular naval activity fail, all naval forces which attempted interception of that naval activity are considered to have remained in port, and play continues as though no naval interceptions had been attempted. The unsuccessful intercepting naval units are not subject to counter-interception or air attack.
B. PARTIAL FAILURE: If the interception dice roll is less than the distance in hexes from that naval force’s base to the interception hex along its previously announced path, the intercepting naval force is not considered to have arrived at the interception hex in time for the first round of naval combat. The intercepting force may join in a later round of naval combat if at least one naval interception of that activity succeeded and the naval battle continues long enough; its participation in the naval battle is deferred by one round for every additional four (European) or two (Pacific) hexes it is from the interception hex:
C. IF NO DICE ROLLED: Naval forces may not intercept if the number of dice they are entitled to roll for their initial interception is zero or less.
22.25 COUNTER-INTERCEPTIONS: Once all naval interception rolls have been made, the moving player may attempt to counter-intercept any interceptions, including those which did not reach the naval interception hex in time for the first round (EXCEPTION: If no interceptions succeeded (22.24A), those interceptions are considered not to have taken place and may not be counter-intercepted).
22.251 SEPARATE INTERCEPTIONS: Intercepting naval forces which sailed along different paths (22.141A) are counter-intercepted separately and may not assist another intercepting naval force which is counter-intercepted.
22.252 COMBINED INTERCEPTIONS: The counter-interception of two or more intercepting TFs traveling along the same path (22.162) is resolved as follows:
A. In the first round of naval combat, the counter-intercepting naval forces engage all the intercepting TFs that have reached the counter-interception hex. This is determined by the distance each intercepting TF must travel to the counter-interception hex along their interception route and their interception die rolls.
B. Intercepting TFs which didn’t reach the counter-interception hex join in subsequent rounds of naval combat as per 22.24B.
C. All the intercepting TFs traveling along the same path are considered to be involved in the counter-interception naval combat, even if it is resolved prior to the round in which they actually participate.
D. If the counter-intercepting force wins the naval combat, all intercepting TFs, including those which were to have joined in later rounds of naval combat, are considered to be defeated and return to port without completing their initial interception.
E. If the intercepting forces wins the naval combat, they complete their interception or return to port, at the intercepting player’s option.
F. Other intercepting naval forces traveling along different paths than the counter-intercepted naval forces (22.251) may not support the counter-intercepted naval forces and do not participate in the ensuing naval combat.
22.253 COUNTER-COUNTER INTERCEPTIONS: Counter-counter-interceptions (interceptions of counter-interceptions) are treated as counter-interceptions.
22.26 INVERSION OF INTERCEPTING NAVAL UNITS: Intercepting naval units are inverted when they return to base if they engage in naval combat with the intercepted naval force. Intercepting naval units are not inverted when they return to port if:
A. All interception attempts fail and there is no naval combat with the enemy naval force sought to be intercepted (22.24A).
B. The naval force they intercept is eliminated or aborts its activity before it reaches the interception hex because of another interception, air or submarine attack.
C. Other friendly naval forces intercept the enemy naval force, but the naval force in question fails in its initial interception attempt and never completes its interception attempt because the naval battle ends before the naval force in question may participate.
D. The naval force is counter-intercepted, but elects to withhold some or all of its naval units from counter-interception naval combat. The withheld units are not inverted.

This rule is required to eliminate a trick on the part of the opponent: if a player attempts to invert a large intercepting naval force which fails to reach its target in its initial attempt by counter-intercepting it with a token force, the intercepting player may choose to use only one or two named ships to eliminate the harassing force, so his remaining forces are eligible to intercept other enemy activities later in that player turn.

22.27 Naval units which do not take part in naval combat, either in the interception hex or from counter-interception en route to the interception hex, return to their original base, are subject to attack or counter-interception by enemy air or naval units en route, and are not inverted once they reach their base unless they participate in naval combat while returning to base. They may not attempt additional interceptions until a subsequent phase.
22.28 ABORTING NAVAL ACTIVITIES: A naval force may abort its naval activity only if:
A. It is attacked by enemy air units or submarines or is engaged in naval combat by intercepting enemy naval units.
B. A friendly naval force with which it was to combine to carry out its naval activity aborted or was eliminated after being attacked by enemy air units or submarines or after engaging in naval combat with intercepting enemy naval units. A naval force is not compelled to abort its activity if a friendly force with which it was to combine aborted or was eliminated.
22.281 Naval forces which abort and return to base may be attacked by enemy air units or submarines or intercepted by uncommitted enemy naval forces which did not previously attempt interceptions during that phase. Naval forces which abort are inverted once they reach their base.
22.282 If a naval force containing transports aborts its naval activity, contemporaneous naval operations involving transports to the destination supply zone are unaffected, but no transports may be used for naval operations relating to the destination supply zone for the remainder of the player turn (21.315).

22.3 NAVAL COMBAT:
22.31 OVERVIEW: Once all naval forces engaged in a naval battle are placed in the interception hex, naval combat is resolved in a series of combat rounds, each of which may consist of one or more of the following, depending on whether the naval forces involved contain fast carriers and submarines:
A. Carrier-based air strikes against land-based air units.
B. Carrier- and land-based air strikes against enemy naval forces.
C. Fleet combat.
D. Submarine attacks.
22.311 This sequence of air strikes, fleet combat and submarine attacks is repeated until one side or the other entirely withdraws or is completely eliminated.
22.32 NAVAL COMBAT ROUNDS: Each round of naval combat consists of air attacks, followed by fleet combat and submarine attacks. In any given naval combat round, all, some or none of these may occur.
22.33 COUNTER-INTERCEPTIONS: If the moving player counter-intercepts an intercepting naval force, the intercepting and the counter-intercepting naval force are placed in the counter-interception hex and the procedure outlined above is followed. The naval force originally intercepted does not participate in this naval battle unless the counter-interception occurs in the interception hex (22.161).
22.34 LAND-BASED AIR:
22.341 Eligible land-based air units (22.433) within range of a naval battle may participate by:
A. Being attacked by carrier-based naval air units (all air units).
B. Providing air cover for a friendly naval force (cover AAS and NAS).
C. Searching (search AAS and NAS).
D. Attacking an enemy naval force (attack AAS and NAS).
22.342 Land-based air units may not attack enemy air or naval bases in the course of naval combat.
22.343 Army air units participate in naval combat as squadrons (23.13).
22.35 RAIDERS: Naval combat involving raiders in an SW box is resolved without the need for combat groups, search and possible surprise, as follows:
A. Each force forms a single combat group, regardless of size.
B. Each combat group is deemed to have found the other. Neither combat group is surprised.
C. Any carrier air strikes are resolved.
D. A single round of fleet combat is resolved.
E. If all the unscreened defending naval units which engaged a raiding group are sunk in naval combat, attacks against transports by raiders which did not engage in naval combat are resolved.
F. Any reinforcing naval units are added to the Western Allied combat group and a second round of air strikes and fleet combat is resolved.

22.4 NAVAL COMBAT SEGMENTS:
22.41 NAVAL COMBAT SEGMENTS: Each naval combat round is divided into the following segments, not all of which will necessarily occur in each naval battle:
A. FORMATION OF COMBAT GROUPS:
B. ATTACKS AGAINST ENEMY AIR BASES:
C. ALLOCATION OF CARRIER-BASED AIR UNITS:
D. ALLOCATION OF LAND-BASED AIR UNITS TO AIR COVER:
E. SEARCH: Each player rolls dice to determine his success in searching for his opponent’s combat groups (22.45).
F. REVEALING COMBAT GROUPS: For each found combat group, the owning player reveals:
G. AIR STRIKES AND ATTACKS: Found enemy combat groups may be attacked by land-based and carrier-based air units, in the following order:
H. FLEET COMBAT: Fleet combat is resolved (22.54).
I. SUBMARINE ATTACKS: Submarine attacks are resolved (22.9).
22.411 BETWEEN ROUNDS OF NAVAL COMBAT:
A. WITHDRAWAL: Each side may withdraw some, all or none of its naval units (22.6).
B. REINFORCEMENT AND ADDITIONAL ROUNDS OF NAVAL COMBAT: If both sides still have naval forces engaged in combat, naval forces which failed to reach the interception hex for the initial round of naval combat (22.24B) or which had to wait until another friendly combat group leaves the naval battle before participating (22.421C) may join in, then another round of naval combat is resolved.

22.42 COMBAT GROUPS:
22.421 FORMATION: Naval forces seeking to engage in naval combat secretly deploy into combat groups as follows:
A. Prior to the first round of naval combat:
B. Each TF which enters an ongoing naval battle after one or more rounds of naval combat have been completed forms a new combat group. Smaller forces which are not part of a TF which enter an ongoing naval battle in the same round combine to form a separate combat group, as set out in 22.421A.
C. No more than six friendly combat groups may take part in any one round of naval combat.
22.422 SPEED: Combat groups are either “fast” or “slow”. A combat group is fast unless it:
A. Contains a slow ship, including damaged ships (20.121).
B. Is carrying cargo (22.427).
22.423 NUMBERING:
A. ASSIGNING COMBAT GROUP NUMBERS: Each player assigns a unique combat group number to his participating naval forces by placing a numbered combat group counter by each TF on his Naval Status Board. Each combat group may be assigned any combat group number between “1” and “6”, subject only to the restriction that no two combat groups may have the same combat group number.
B. SECRECY: Each player reveals his combat group numbers to the opposing player by placing duplicate combat group markers on the Naval Combat Chart. The composition of each combat group remains hidden on each player’s Naval Status Board until that combat group is attacked.
22.424 RENUMBERING: Once a combat group number has been assigned, this number may only be changed if the combat group evades fleet combat (22.523).
22.425 STATUS: At any given point in a naval battle, each combat group has one of the following statuses:
A. ACTIVE: If a combat group’s number is equal to or less than the number of the current combat round, that combat group is “active”.
B. DISTANT: If a combat group’s number is greater than the number of the current combat round, that combat group is “distant”.
C. PENDING: Combat groups that have not yet joined in naval combat are “pending”. This occurs when a combat group:
D. EFFECTS:
22.426 COMBINING PROHIBITED: Combat groups fight separately and may never combine with other combat groups.
22.427 CARGO: Cargo remains with the combat group to which it was originally assigned prior to the first round of naval combat (21.35). A combat group which is carrying cargo or protecting sea supply is considered to be slow (22.422) and, if engaged in fleet combat, incurs a -1 modifier to its fleet combat dice roll, while the opposing force receives a +1 modifier to its fleet combat dice roll (22.552B).
22.428 EFFECT OF COMBAT GROUPS ON SEARCH:
A. One search die is rolled for each friendly active combat group consisting of at least ten undamaged naval factors (22.451D).
B. One search die is rolled for each distant combat group containing at least one fully operational fast carrier. No additional modifier is received for having more than one fully operational fast carrier in a combat group (22.451D).
C. Pending combat groups never contribute to search.

22.43 ATTACKS AGAINST ENEMY BASES:
22.431 COUNTERAIR RESOLVED BEFORE SEARCH: Once each naval force has been divided into combat groups as required, each player decides whether and which of his carrier-based naval air units will counterair enemy land-based air units within range of his naval force. Each player then announces the number of NAS counterairing each enemy base and resolves one round of counterair combat for each enemy air base, in whatever order he wishes.
22.432 SURVIVING CARRIER-BASED AIR UNITS: Naval air units which counterair enemy land-based air units may not conduct other air operations during that combat round, return to their carriers at the same time as carrier-based air units that conducted air strikes and flew CAP (22.463), and may be used in subsequent rounds of the naval combat.
22.433 SURVIVING LAND-BASED AIR UNITS: Land-based air units which are not eliminated or forced to abort by the counterair combat result may participate in the round of naval combat in which they were counteraired by providing air cover, searching or later attacking enemy naval units. Surviving land-based air units, including those forced to abort in previous rounds of counterair combat, may be used in subsequent rounds of the naval combat.
22.434 THE FINAL ROUND OF COUNTERAIR COMBAT: After the naval combat is concluded, the status of defending land-based air units for the remainder of the player turn is determined by the attacker’s final counterair combat result during naval combat (18.526A).

The combined effect of these rules is that the effect of counterair attacks by carrier-based naval air units is determined each round. All surviving land-based air is eligible for use in each subsequent round of naval combat, even if previously subject to an “abort” result, and must therefore be counteraired each round to be neutralized. Land-based air units subject to an “abort” result may participate in subsequent rounds of naval combat, even though they will be inverted at the end of the naval battle because of the earlier “abort” result.


22.44 ALLOCATION OF AVAILABLE AIR UNITS:
22.441 CARRIER-BASED NAVAL AIR UNITS: After counterair attacks are resolved, each player secretly allocates his remaining available carrier-based naval air units to either:
A. Air strikes against enemy naval units; or
B. Combat air patrol over their combat group.
22.442 ELIGIBLE LAND-BASED AIR: Land-based air units are eligible to participate in a naval battle if they:
A. Are uninverted in an operational base within range of the hex in which naval combat is taking place.
B. Have not already been committed to ground support, defensive air support, the interception of defensive air support or the interception or counter-interception of air transport missions.
C. Have not been forced to abort by a counterair attack by enemy carrier-based naval air units in the current round of naval combat (22.433).
22.4421 AIR COVER:
A. Land-based air units which fly air cover are secretly assigned to a specific friendly combat group.
B. The commitment of land-based air units to air cover is announced when made, although the combat group to which they are assigned is not revealed until an air strike against that combat group is made.
C. Land-based air units which provide air cover may defend against both surprise air strikes and non-surprise air strikes (22.461) in the current combat round and participate in subsequent rounds of naval combat in the same naval battle unless eliminated in air combat with enemy air units.
22.4422 AIR SEARCH:
A. Eligible search AAS and land-based NAS which were not committed to air cover against enemy carrier attacks may help search for enemy naval forces (23.11B).
B. NAS used to search may not attack enemy naval forces later in the same combat round.
C. For each air squadron allocated to search, one additional die is rolled for search, up to a maximum of three additional dice (22.451A).

22.45 SEARCH:
22.451 SEARCH ROLLS: After carrier-based air units have been assigned to offensive or defensive tasks, and land-based air units have been assigned to air cover, each player determines how many search die rolls, if any, he may make to search for his opponent’s combat groups. The number of search rolls made is determined as follows:
A. AIR: One die for each land-based air squadron assigned to search (22.4422). (Maximum: +3).
B. CODEBREAKING: If either player obtained a search advantage from playing tactical codebreaking cards (48.32B) or from the tactical advantage associated with a Magic interception (48.62), that player rolls one additional search die and his opponent rolls one fewer search die. (Maximum: +/-1).
C. ADDITIONAL COMBAT ROUNDS: One additional die is rolled for each round of naval combat that has been resolved in a naval battle (one die in the second round; two dice in the third round; and so on. There is no maximum).
D. COMBAT GROUPS:

Search Table - 22.45

Number of search die rolls

+1

For each land-based air squadron assigned to search (22.451A). (Maximum: +3).

+/-1

Codebreaking advantage (48.51A, 48.62).

+1

Each previous round of naval combat. (No maximum).

+1

Each friendly active combat group consisting of at least ten undamaged naval factors (22.451D). (Maximum: +6).

+1

Each friendly distant combat group containing at least one fully operational fast carrier (22.451D). (Maximum: +5).

Search results

No search result

The enemy combat group remains hidden and may not be attacked.

One or more search results

The enemy combat group is found and is eligible to be attacked. The owning player must reveal whether the combat group consists of less than ten naval factors, how many fast carriers it contains, its speed and whether it is carrying cargo.


22.452 SEARCH RESULTS: If at least one search die roll matches the number of an enemy combat group, a search result is achieved against that combat group.
A. NO SEARCH RESULT: If no search result is achieved, the enemy combat group remains hidden.
B. ONE SEARCH RESULT: If a search result is achieved, the enemy combat group is found and the owning player must reveal:
C. MULTIPLE SEARCH RESULTS: If more than one search result against the same combat group is achieved, that enemy combat group may be attacked more than once:
22.46 AIR STRIKES: Once all search die rolls are made, air strikes are resolved at set out below. Naval air units allocated to air strikes against enemy naval units are not compelled to attack.
22.461 AIR STRIKES SEQUENCE: Air strikes are resolved in the following sequence:
A. One surprise air strike by carrier-based naval air units (only if no friendly combat groups were found).
B. Non-surprise air strikes by carrier-based and land-based air units, with the player with the greater number of search results (the intercepting player, if tied) launching his air strikes first. The first player decides on the target of his second air strike after resolving his first air strike, and so on, until he has resolved all his air strikes; his opponent then resolves his air strikes. Carrier-based and land-based air units may combine to make an air strike.
22.462 RESTRICTIONS:
A. Air strikes may only be launched against found enemy combat groups.
B. One air strike may be launched for each search result achieved against the enemy combat group.
C, The number of attacking air squadrons in each air strike is limited by the Air Nationality DRM of the attacking air squadrons (23.73).
D. If no friendly combat groups were found, a single surprise air strike by carrier based naval air units against one found enemy combat group may be launched (23.741).
E. If one or more friendly combat groups were found, only non-surprise air strikes may be launched.
F. See 23 for the details of air strikes.
22.463 RETURNING NAS AND MISSING CARRIERS: Once all air strikes are resolved, all surviving land-based air units return to land bases and all surviving naval air returns to their carriers.
A. TIMING: All naval air units return to their carriers before fleet combat is resolved.
B. NAVAL AIR UNITS FLYING COMBAT AIR PATROL: Naval air units flying combat air patrol may land on:
C. NAVAL AIR UNITS RETURNING FROM ATTACKS: Naval air units returning from counterair attacks against land-based air and air strikes against naval units may land on:

22.5 FLEET COMBAT:
22.51 FLEET COMBAT: Fleet combat is resolved after all air strikes are resolved.
22.52 RULES OF ENGAGEMENT: Fleet combat must involve at least one active combat group, and may only be avoided if one side evades fleet combat (22.523).
22.521 MECHANICS: The following steps are followed in the indicated sequence:
A. Active combat groups with the same combat group number pair off in fleet combat.
B. Starting with the lowest numbered unpaired combat group, each active unpaired combat group then pairs off with the next highest unpaired opposing active combat group, until one side has all its active combat groups paired.
C. Fleet combat is then resolved for these engagements.
D. Each active combat group which either did not engage in fleet combat with an opposing active combat group or which sank all the naval units in an opposing active combat group it engaged in fleet combat may then engage in fleet combat with:
E. Fleet combat is then resolved for these engagements.
22.522 LIMITS ON FLEET ENGAGEMENTS: Subject to 22.521, in each combat round:
A. ACTIVE COMBAT GROUPS: There is no limit on the number of combat groups that may engage opposing active combat groups in fleet combat.
B. DISTANT COMBAT GROUPS: Each fast, active combat group that engages a found distant combat group in fleet combat counts towards the limit on the number of times that combat group may be attacked in that combat round (22.452C ).

A combat group with a number higher than the current combat round (a “distant” combat group) may only be involved in fleet combat if it is found by the opponent’s search rolls and if the opponent has a fast combat group with a number equal to or lower than the current combat round (an “active” combat group) that did not pair off against an opposing active combat group.
This doesn’t mean higher numbered combat groups are completely safe (if found, they may be subject to an air attack or fleet combat; if found twice, they may be subject to both), but they are safer for longer than they would be if they had a lower combat group number.

22.523 EVADING FLEET COMBAT: Combat groups may evade fleet combat as follows:
A. DISTANT COMBAT GROUPS ONLY: Only distant combat groups may evade fleet combat; active combat groups must fight.
B. SPEED: Only fast distant combat groups may evade fleet combat. A slow distant combat group must fight.
C. MANEUVERING ROOM: A fast distant combat group may only evade fleet combat if a higher combat group number is available. If no such number is available, the combat group may not evade fleet combat.
D. MECHANICS: The decision whether to evade fleet combat is made after the composition of the fast, unpaired, active combat group seeking fleet combat is revealed.
E. EFFECTS: When a fast distant combat group evades fleet combat:
22.524 WITHDRAWAL OF DAMAGED NAVAL UNITS: At any time between fleet combat engagements, damaged ships may be withdrawn from a combat group that wishes to initiate or evade fleet combat so that the combat group doesn’t have its speed reduced by the presence of those damaged ships (20.121A).
A. Damaged ships that withdraw from a combat group that initiates fleet combat withdraw from naval combat at the end of the combat round.
B. Damaged ships that withdraw from a combat group that evades fleet combat are eliminated as having been abandoned.
C. Undamaged naval units may not withdraw from naval combat during a combat round to avoid fleet combat; withdrawal from naval combat is permitted only at the end of a combat round (22.61).

EXAMPLE: A naval battle occurs in which Japan and the U.S. each have three combat groups. All are fast except for one American combat group, which is carrying an invasion force.

At the start of the battle, both sides number their combat groups as follows: Japan: CG1, CG2, CG4; U.S.: CG1, CG3, CG5. Japanese CG4 and American CG3 contain fast carriers; American CG5 is carrying cargo.

Neither side has land-based air within range of the naval combat and there is no codebreaking.

Round 1: The search modifiers (22.451) are:

Japan: Zero for the combat round, one for active CG1 and one for the fast carrier(s) in CG4 = 2 dice. Japan rolls 3 and 6.

U.S: Zero for the combat round, one for active CG1 and one for the fast carrier(s) in CG3 = 2 dice. The U.S. rolls 1 and 2.

The search results for Round 1 are:


Naval Combat Chart - Round 1

Japan

Combat Groups

Allies

Hidden

Found

Found

Hidden

 

1

 

 

2

 

 

 

 

3

 

 

4

 

 

 

 

5

 

 

 

6

 

 


In Round 1, neither side may launch a surprise air strike (both sides had combat groups found by the opponent - 23.7411B). The Japanese may launch a non-surprise air strike against American CG3 (the only American combat group found by the Japanese); the U.S. may launch non-surprise air strikes against either or both of Japanese CG1 and CG2, as the U.S. found both of these Japanese combat groups.

After these air strikes are resolved, the opposing CG1s engage in fleet combat (22.521A).

Round 2: The search modifiers are:

Japan: One for the combat round, two for active CG1 and CG2 and one for the fast carrier(s) in CG4 = 4 dice. Japan rolls 1, 4, 5 and 5.

U.S: One for the combat round, one for active CG1 and one for the fast carrier(s) in CG3 = 3 dice. The U.S. rolls 2, 4 and 6.

The search results for Round 2 are:


Naval Combat Chart - Round 2

Japan

Combat Groups

Allies

Hidden

Found

Found

Hidden

 

1

 

 

2

 

 

 

 

3

 

 

4

 

 

 

 

5

 

 

 

6

 

 


In Round 2, the Japanese may launch a non-surprise air strike against American CG1 or CG5; the U.S. may launch a non-surprise air strike against Japanese CG2 or CG4.

After these air strikes are resolved, the opposing CG1s engage in fleet combat (22.521A).

Japanese CG2, as an unpaired active combat group (22.521D) now has two options. It can engage in fleet combat with American CG1 (an opposing active combat group) or American CG5 (an opposing distant combat group found by a search roll). This second option would be available even if Japan launched an air strike against American CG5 because Japan had two search results for American CG5 (22.452).

If American CG5 were fast, it could evade, and would be renumbered as CG6. However, it is slow, so it has to accept fleet combat.


22.53 RESOLVING FLEET COMBAT: When fleet combat occurs, all the naval units in the two opposing combat groups engage in the fleet combat. A player may not commit only part of a combat group to fleet combat, although naval units may be screened from combat (22.531C).
22.531 SHIP CATEGORIES IN FLEET COMBAT: When fleet combat occurs, the fleet units of each side are divided into three categories:
A. CAPITAL SHIPS: Named capital ships;
B. LIGHT SHIPS: Cruisers, destroyers which are not carrying cargo, and CVEs;
C. SCREENED SHIPS:
22.54 FLEET COMBAT SEQUENCE: Each round of fleet combat follows the sequence set out below:
A. CAPITAL SHIPS PAIR OFF: The opposing capital ships pair off:
B. SURPLUS CAPITAL SHIPS SELECT TARGETS: Surplus capital ships may then either:
C. RESOLVE CAPITAL SHIP FIRE: Once all capital ships have selected targets, capital ship fire is resolved, using the Naval Attack Table (22.55).
D. LIGHT SHIPS PAIR OFF: Once capital ship fire is resolved, the surviving, undamaged opposing light ships pair off:
E. SURPLUS LIGHT SHIPS SELECT TARGETS: Surplus light ships may then either:
F. RESOLVE LIGHT SHIP FIRE: Once all light ships have selected targets, light ship fire is resolved, using the Naval Attack Table (22.55).
G. RESOLVING FIRE AGAINST SCREENED SHIPS: Fire is then resolved against any screened ships selected as targets by capital and light ships that have withheld their fire.
H. AFTER FLEET COMBAT: After any fleet combat is resolved for the round:
22.55 NAVAL ATTACK TABLE: Fleet combat effects are determined by rolling two dice and consulting the Naval Attack Table. Fire against a single target is combined and resolved by a single fleet combat dice roll for that target. A dice roll of less than two is treated as a two.

Naval Attack Table - 20.51, 22.55, 23.44

AS

FF

Dice Roll

2

3

4

5

6

7

8

9

10

11

12+

-

1

0

0

0

0

0

0

1

1

1

1

1

-

2

0

0

0

0

0

1

1

1

1

1

2

1

3

0

0

0

0

1

1

1

1

1

2

2

-

4

0

0

0

1

1

1

1

1

2

2

3

2

5-6

0

0

1

1

1

1

2

2

2

3

3

3

7-9

1

1

1

1

2

2

2

3

3

3

4

4

10-12

1

1

2

2

2

3

3

3

4

4

5

5

13-15

2

2

2

3

3

3

4

4

5

5

6

6

16-18

2

2

3

3

3

4

4

5

5

6

6

7

19-21

2

3

3

3

4

4

5

5

6

6

7

8

22-24

3

3

3

4

4

5

5

6

6

7

7

9

25-27

3

3

4

4

5

5

6

6

7

7

8

10

28-30

3

4

4

5

5

6

6

7

7

8

8

11

31-33

4

4

5

5

6

6

7

7

8

8

9

12

34-36

4

5

5

6

6

7

7

8

8

9

9

13

37-39

5

5

6

6

7

7

8

8

9

9

10

14

40-42

5

6

6

7

7

8

8

9

9

10

10

15

43-45

6

6

7

7

8

8

9

9

10

10

11

16

46-48

6

7

7

8

8

9

9

10

10

11

11

17

49-51

7

7

8

8

9

9

10

10

11

11

12

18

52-54

7

8

8

9

9

10

10

11

11

12

12

19

55-57

8

8

9

9

10

10

11

11

12

12

13

20

58-60

8

9

9

10

10

11

11

12

12

13

13

Modifiers - Air Attacks on Naval Units

   +#         attacker’s Air Nationality DRM

   -#         defender's Naval Nationality DRM

   +1         naval air units attacking ships at sea

   +1         if the attacker achieves a surprise level of 3 or greater

Modifiers - Fleet Attacks on Naval Units

   +/-#      Naval Nationality DRMs (22.552A)

   +/-1      If one of the combat groups involved is carrying out a naval activity which reduces its effectiveness (22.552B)

If more than 20 air squadrons engage in combat, the result is determined by consulting the "20" row and whatever other row is required to equal the total number of air squadrons engaged. If more than 60 fleet factors engage in combat, the result is determined by consulting the "58-60" row and whatever other row is required to equal the total number of fleet factors engaged.

Results

Named ships and cruisers: A named ship or cruiser is damaged if it incurs naval attack effects one less than its size in factors and is sunk if it incurs naval attack effects equal to or greater than its size in factors.

Cruiser groups: If a group of light ships consisting only of cruisers incurs an odd number of hits, the odd hit damages one cruiser.

One-factor naval units: If a group of ships consists only of destroyers, CVEs, transports or a combination of the three, each hit sinks a destroyer, CVE, or transport factor.

Mixed light forces: Naval attack effects incurred by a light force consisting of both cruisers and one-factor naval units are distributed evenly between the cruisers and one-factor naval units, subject to the proviso that the number of one-factor ship factors sunk may not exceed the number of cruiser factors sunk until all the cruisers in the force are sunk (20.551).


22.551 Each side’s fleet combat dice roll may be modified by the nationality and activity of the naval forces engaged. A favorable modifier for one side results in an equally unfavorable modifier for the other.
22.552 MODIFIERS: Fleet combat dice rolls are subject to the following modifiers:
A. NAVAL NATIONALITY DRMs: DRMs are applied to fleet combat according to the nationality of the respective combatants, as modified by any tactical codebreaking advantage (48.51B).

Naval Nationality Chart - 22.552A, 23.441B

DRM

Nationality

3

Japan

2

Germany, Britain, United States, Sweden, Australia

1

Italy, France

0

Russia, Greece, Rumania, Spain, Turkey, Dutch East Indies

Modifiers

+1

Five-factor battleships

+1

German submarines

-2

Japanese and American CVLs; all CVs and CVEs

-1

German, Italian and British CVLs; all CVBs

-1

Naval units in partial supply or subject to naval oil effects.

Explanation: When fleets with different DRMs engage in fleet combat, the two DRMs are compared. The higher ranking side adds the difference to its fleet combat dice roll, and the lower ranked side subtracts the difference from its fleet combat dice roll. Air attack dice rolls against naval units are reduced by the DRM of the attacked naval units.


B. NAVAL ACTIVITIES: DRMs are applied to fleet combat according to the activity being carried out by the respective combatants.
22.56 FLEET COMBAT EFFECTS: For the effects of fleet combat, see 20.5.

22.6 WITHDRAWAL FROM NAVAL COMBAT:
22.61 WITHDRAWAL ALWAYS PERMITTED: Either side may withdraw some or all of its naval forces from a naval battle at the end of any round of naval combat, whether or not there was naval combat in that round.
A. The loser of the previous round of naval combat announces his intention first (the loser is the player who lost more naval factors in the previous round of naval combat; if tied, the player who had more naval factors damaged; if still tied, the intercepting player).
B. Damaged naval units may withdraw without additional protection, or together with undamaged naval units to increase their defense against enemy attack.
C. Naval units which voluntarily withdraw from naval combat are considered to have been “defeated” and abort their mission, regardless of the ultimate outcome of the naval combat in which they participated.
D. Naval units in a combat group that was not attacked in a combat round may only withdraw if their entire combat group withdraws.
22.62 INTERCEPTION OF WITHDRAWING NAVAL UNITS: Withdrawing naval units may be attacked by enemy air units or intercepted by enemy naval units in any hex along their route back to base (22.18).
22.63 RETURN TO BASE: At the conclusion of naval combat, naval units may, subject to stacking limits, return to their base of origin or any base within 20 (Europe) or 10 (Pacific) hexes from the hex in which naval combat occurred, subject to the following exceptions:
A. Naval units defeated in naval combat while attempting a base change or NR return to their original base (21.33).
B. Destroyers carrying units being sea transported, conducting a seaborne invasion or being sea escorted must return to their base of origin; the units they were carrying must return to their base of origin.
C. During the combat phase, naval units may not return to a base which is the target of a seaborne invasion unless it is the only base available.
D. If overstacking of any type of unit results from a return to base, that overstacking must be remedied by the end of the player’s movement or redeployment phase, whichever occurs first. If the player is unable to remedy the overstacking, excess units of his choice are eliminated (12.15, 18.15).
E. Overstacking of naval units resulting from a failed NR results in the elimination of the excess naval units, as they may not attempt a second NR during that redeployment phase (21.112, 21.222, 28.523).

22.7 ADDITIONAL ROUNDS OF NAVAL COMBAT:
22.71 WHEN NAVAL BATTLES END: A naval battle ends when, at the end of a combat round, any of the following situations exist. Additional naval forces that haven’t yet entered the naval battle are not taken into account:
A. One side withdraws all its combat groups from combat.
B. One side has no operational carriers in the naval battle and evaded fleet combat with all its combat groups.
C. One or both sides have no undamaged naval units left in the battle (EXCEPTION: If one side is tracing sea supply, it may opt to continue the battle until the sea supply line is disrupted).
22.72 VICTORY AND DEFEAT: The victor in a naval battle is determined by how the naval battle ended (22.71):
A. The side that withdraws is considered to have lost the naval battle.
B. The side that evaded fleet combat is considered to have lost the naval battle.
C. The side with no undamaged naval units is considered to have lost the naval battle.
22.73 MULTIPLE ROUNDS OF NAVAL COMBAT: If a naval battle continues past the first combat round, a second round of combat takes place, and so on, unless the naval battle ends.
22.74 CARRIER-BASED NAVAL AIR UNITS: Carrier-based naval air units may be used repeatedly during each round of carrier combat, as well as for subsequent offensive missions, and may always be used against intercepting enemy air and naval units.

EXAMPLE: Three Japanese fleet carriers, with their complement of nine NAS, set sail to bomb an American naval base. They are intercepted and win the ensuing naval combat. The surviving naval air units complete their mission. The carriers, now inverted, are then NRed and subsequently intercepted by other American forces. The Japanese naval air units may participate in the ensuing naval combat (assuming there are any left).


22.8 EFFECTS OF NAVAL COMBAT:
22.81 After naval combat is resolved:
A. NAVAL FORCES CONDUCTING AN ACTIVITY:
B. INTERCEPTING NAVAL FORCES: After the resolution of naval combat, surviving intercepting naval forces return to base and are inverted for the remainder of the player turn (EXCEPTION: Patrols).
C. COUNTER-INTERCEPTING NAVAL FORCES: Counter-intercepting naval forces which supported the victorious intercepted force adopt the mission of that force, if otherwise permitted to do so.
D. Counter-counter-intercepting forces which supported a victorious intercepting force adopt the interception mission.
22.82 EFFECTS ON CARGO:
A. If combat losses reduce the number of destroyer factors or transports involved in sea transport, seaborne invasion or the sea escort of units, oil counters or BRP grants below the number required, the excess units, oil counters or BRPs are immediately eliminated, as necessary, to reflect the naval force’s reduced carrying capacity.
B. If the carrying capacity of a TF or combat group is reduced below the minimum requirement, cargo assigned to that TF or combat group is lost, even if the carrying capacity of a naval force as a whole is sufficient.
C. Surviving destroyers freed from cargo duty by the sinking of their cargo are eligible to provide shore bombardment in conjunction with the same mission.

22.9 SUBMARINE ATTACKS:
22.91 INTERCEPTION BY SUBMARINES:
22.911 Submarines based on the board intercept enemy naval activities and enemy naval units returning to base in the same manner as other naval units (22.2). Submarines in an SW box may not intercept. For restrictions on the ability to conduct submarine warfare against enemy transports, see 25.7, 25.8 and 25.9.
22.912 On-board submarine attacks are resolved using the Submarine Attack Table (22.94). Submarines operating against enemy transports in an SW box resolve their attacks using the SW Combat Table (24.62).
22.913 SUBMARINE PATROLS: Submarines may patrol in the same manner as other naval units (21.41), subject to the same restrictions as other patrols. Submarines patrol independent of other naval forces. Submarine patrols may remain at sea throughout the opposing turn, but are subject to air attack by enemy land-based air units if they do so (21.4184C).
22.914 SUBMARINES ATTACKS DURING NAVAL COMBAT: Submarines accompanying a naval force which was intercepted by enemy naval units, or which intercept enemy naval units in a hex in which naval combat occurs, may attack the enemy naval units, provided the enemy naval units were found during that round of naval combat or which revealed their location by engaging in fleet combat.
22.915 SUBMARINE INTERCEPTION INDEPENDENT OF OTHER NAVAL UNITS: Each submarine factor rolls for interception separately, independent of interception by other naval units, including other submarines. Submarines may intercept eligible enemy naval forces in a different hex from other intercepting naval units, including other intercepting submarines.
22.916  RESOLVING SUBMARINE INTERCEPTIONS:
A. SUBMARINES IN PORT AND ON DEFENSIVE PATROLS: Submarines based in port and on defensive patrols intercept in the same manner as other naval units, although they roll one fewer die than fast ships (22.22I).
B. OFFENSIVE PATROLS: Submarines on offensive patrols may support friendly naval forces which are intercepted (22.163).
22.917 ATTACKS AGAINST INTERCEPTING SUBMARINES PROHIBITED: Intercepting submarines are not subject to counter-interception by enemy naval units or attack by enemy air units as they leave port or move to their interception hex.
22.918 MURMANSK CONVOYS: For submarine attacks against Murmansk convoys, see 40.45 and 40.46.
22.92 EFFECT OF INTERCEPTION ATTEMPTS: Submarines which succeed in their interception attempts must attack the enemy naval force they intercepted if able to do so. Surviving submarines return to base after attacking and are inverted for the remainder of the current player turn, in the same manner as other intercepting naval units. If the enemy naval force is sunk by prior air, fleet or submarine attack, or the naval battle in which they are participating ends, before the intercepting submarines have the opportunity to attack, the submarines return to the hex from which they intercepted, are not inverted, and may attempt interceptions in subsequent phases of the current player turn.
22.921 TIMING OF SUBMARINE ATTACKS: Submarine attacks are resolved after air attacks and fleet combat are resolved, at the option of the attacker. If no naval combat occurs in relation to a naval activity, submarine attacks are resolved immediately upon interception, after the resolution of any air attacks on the intercepted naval force.
22.93 SUBMARINE TARGETS:
A. AGAINST SINGLE ENEMY COMBAT GROUPS: Whenever submarines attack a naval force, that force deploys into combat groups, following the procedure set out in 22.42 (EXCEPTION: A naval force attacked by submarines outside of naval combat may contain more than six combat groups). Submarine attacks are made against single enemy combat groups, whether the enemy naval units are engaged in naval combat or not. Submarines never attack a multi-TF naval force as a whole.
B. ONLY REVEALED COMBAT GROUPS MAY BE ATTACKED: Submarines attacking during naval combat may only attack found enemy combat groups and hidden enemy combat groups which revealed their location by engaging in fleet combat.
C. SUBMARINES ATTACK ALONE: Submarines may not attack in conjunction with other naval units.
D. ATTACKS RESOLVED SEPARATELY: After all submarine attacks have been announced, each attack is resolved separately.
E. SELECTING TARGETS: Each attacking submarine targets a category of defending naval units: fast carriers; capital ships (non-carrier named ships); or light ships.
22.94 RESOLVING SUBMARINE ATTACKS: Once the target of an attacking submarine is determined, the attack is resolved by rolling two dice on the Submarine Attack Table. Each submarine factor attacks separately and may attack only once per player turn.

Submarine Attack Table - 22.94

DR

2

3

4

5

6

7

8

9

10+

Sub

*

0

0

1

1

2

2

3

3

Modifiers

+/-#

Naval Nationality DRM (22.552A, 22.9411)

+/-#

Relative torpedo and ASW research levels (22.9412)

+/-#

Every three land-based air squadrons used for search in the submarine attack hex, fully operational fast carriers and CVEs in the attacked naval force (round down) (22.9413)

-#

Every three destroyer factors in the attacked naval force, including destroyers which are carrying units (round down) (22.9414)

-#

Every three ASW factors in the relevant SW box in excess of the corresponding number of enemy submarines (round down) (22.9415)

-1

For each previous submarine attack made against the defending naval force in that naval combat round (22.9416)

+1

If the attacked naval unit is damaged or involved in carrying out a naval activity which reduces its effectiveness (22.9417)

+/-1

Submarine or ASW codebreaking advantage (22.9418)

One dice roll is made for each attack. On a “*” result, the attacking submarine factor is eliminated.

Determine the net modifier for each category, then determine the overall net modifier. The maximum effect from each modifier in italics is +/-2.

The maximum overall modifier for a submarine attack cannot exceed +/-4.

Advanced submarines always attack at net +1.

One die is rolled to determine the target of each submarine attack (22.93E).


22.941 SUBMARINE ATTACK MODIFIERS: The overall net modifier for each submarine attack dice roll may never be greater than +/-4. This net modifier is determined as follows (EXCEPTION: Advanced submarines always attack at a net +1 modifier):
22.9411 NAVAL NATIONALITY DRMs: The submarine attack dice roll is increased or decreased by the difference between the attacker's and the defender's Naval Nationality DRMs, as modified by any tactical codebreaking advantage (48.51B).
22.9412 TORPEDO AND ASW RESEARCH RESULTS:
A. The submarine attack dice roll is increased or decreased by the difference between the attacker’s torpedo and the defender’s ASW research results.
B. The maximum effect of this modifier for each submarine attack is +/-2.
22.9413 SEARCHING LAND-BASED AIR AND CARRIERS:
A. The submarine attack dice roll is:
B. Air units which participated in naval combat by searching during a naval combat round also modify submarine attacks against naval forces during that naval combat round.
C. The attacker assigns air squadrons to search, then the defender assigns air squadrons to search, then the net modifier is determined.
D. Air units in non-operational bases have no effect on submarine attacks.
E. The maximum net increase or reduction from this modifier for each submarine attack is +/-2.
22.9414 DESTROYERS:
A. The submarine attack dice roll is reduced by one for every three destroyer factors in the attacked naval force, including destroyers which are carrying units (round down).
B. The maximum reduction from this modifier for each submarine attack is -2.
22.9415 EXCESS ASW:
A. The submarine attack dice roll is reduced by one for every three ASW factors (round down) in the relevant SW box in excess of the number of enemy submarines eligible to conduct submarine warfare in that SW box (25.4).
B. Submarines are considered to be “eligible to conduct submarine warfare” for the purposes of this rule during either player's turn. All ASW factors in the relevant SW box are counted. The modifier for ASW applies to all enemy submarine attacks for the turn in question, subject to the following restrictions:
C. The maximum reduction from excess ASW for each submarine attack is -2.
22.9416 MULTIPLE ATTACKS:
A. The attacker incurs a -1 modifier on his submarine attack dice roll f or each previous submarine attack made against the defending combat group in that naval combat round.
B. This modifier applies when submarines attack different targets (such as different named ships) in the same TF or combat group.
C. For the purpose of this modifier, submarine attacks independent of naval combat are considered to take place in the same round of naval combat if they occur in the same hex.
D. The first submarine factor which attacks does not incur this modifier; the second incurs a -1 modifier; the third incurs a -2 modifier; and so on.
E. There is no limit to this modifier other than the number of submarines attacking.
22.9417 ADDITIONAL MODIFIERS:
A. DAMAGED SHIPS: The attacker receives a +1 modifier on his submarine attack dice roll when attacking a damaged named ship or a group of light ships containing a damaged cruiser. The damage may have been caused by previous submarine attacks in that combat round.
B. NAVAL ACTIVITIES: The attacker receives a +1 modifier on his submarine attack dice roll when attacking any naval unit in a TF or combat group containing destroyers or transports conducting sea transport, seaborne invasion, sea supply or the sea escort of units, oil counters or BRPs; or when attacking an undefended sea supply line. This modifier applies even if the mission is intercepted before it has reached the base of embarkation or if it is intercepted while returning to port after it completes its mission.
C. The modifiers for damage and naval activities are not cumulative; a submarine attack on a damaged naval unit in a naval force which is protecting sea supply or carrying cargo receives a +1, not a +2, modifier, in addition to whatever other modifiers may apply.
22.9418 CODEBREAKING: If the attacker achieves a submarine warfare codebreaking advantage for on-board submarine attacks, a +1 modifier is applied to the submarine attack; if the defender achieves an ASW codebreaking advantage for on-board submarine attacks, a -1 modifier is applied (48.41B).
22.9419 COMPOSITION OF TARGETS: Each TF or combat group in a naval force defends against submarine attacks separately.
22.942 Cruisers, named heavy ships, fast carriers which do not have their full complement of naval air, damaged fast carriers and undefended sea supply lines have no submarine defense value.
22.943 EFFECTS OF SUBMARINE ATTACKS:
22.9431 GENERAL: For the effects of submarine attacks, see 20.5.
22.9432 DESTROYER LOSSES: If an attacked TF or combat group contains destroyers, all, some or none of the losses inflicted by submarines on those destroyers may, at the defender’s option, be taken from uninverted destroyers in the base of origin of the defending TF or combat group, a port through which a sea supply line passed (sea supply only), or from uncommitted destroyers in the SW box through which the naval activity passed.
22.9433 OTHER LOSSES: Losses inflicted by submarines on CVEs, cruisers and named ships must be taken from the attacked naval force and may not be taken by naval units in an SW box.
22.9434 SEA SUPPLY LINES: Undefended sea supply lines are disrupted if attacked by submarines (30.381). If one or more destroyer factors are assigned to the protection of a sea supply line, submarine losses to the protecting destroyers may be taken from uncommitted destroyers as per 22.9432.
22.9435 DESTROYERS AND TRANSPORTS CARRYING CARGO: For the effect of submarine attacks on destroyers and transports carrying cargo, see 20.58B and 20.59.