Coral Sea Campaign Rules

Coral Sea Campaign Rules

General Overview

Coral Sea is a simulation of the action off New Guinea in eary 1942. The basic objectives differ for the two sides. The Japanese need to capture Port Moresby and the Allies have to prevent this. Each turn the two sides search for each others ships, ready and launch aircraft, conduct sea battles if necessary, and move their fleets.

Orders of battle and original positions of forces were can be found on the following links:

Strategic map

The map is divided into eighty eight (88) AREAS, numbered A1 to K8, and each area is divided into nine (9) ZONES, labeled A to I. Ships cannot be ordered to travel across land areas. See the Coral Sea campaign map.

Strategic Turns

At the beginning of the game players note location of task forces as indicated on the deployment sheets and give orders to aircraft. Each strategic turn follows the following sequence: During night turns no air activity is possible.

Task Force Size

Task forces represent groups of ships which operate together for offensive and defensive purposes. Therefore there are limitations on their size. A task force is a group of ships that occupy the same zone on the map.

If a task force operates with fewer than three ships they become vulnerable to submarine attack. For each turn that a task force operates with two or fewer ships roll 1d10. If a one is rolled the task force was attacked by a submarine. Randomly select a ship and roll 3d6. The result is the amount of damage taken by the selected ship.

If a task force operates with more than seven ships there is a chance of a collision. Each turn that the task force has eight or more ships roll 1d10 for each ship over seven. Any rolls of "1" indicate a collision has occurred. For each collision randomly select two ships form the force. For each ship roll 2d6 and the result is the amount of damage the ship takes from the collision. There is one exception - the Japanese Invasion force of thirteen ships may operate as a single body if no ships are added to the task force.

Fuel and Oilers

Oilers are necessary for fuel for the fleet. To reflect this, on the last daylight turn of each day destroyers must be within three areas of either an oiler or a base that has an available oil supply. If not, all destroyers must move toward until they are in the same area as an oiler or base. If they do not do this by nightfall of the next day, they are considered out of fuel and must remain stationary until an oiler enters the zone they are in.

Search Procedures

  1. Search area with base: Each turn a check is made in ALL areas where forces have bases. This is automatic and does not have to be declared.
  2. Cruiser searches. Each task force that contains a cruiser may conduct one search in any area surrounding the task force, if the cruiser is equipped with search planes.
  3. Search areas with search planes: Each player has planes that are specifically designed for searches. These are the Catalina and Hudson for the allies and the Emily and Mavis for the Japanese. These planes have a flight range and are based the same as any aircraft. Each turn the player may order some, all, or none of these planes to search areas within their range. They must be readied the turn before they search. Searches by non search planes would be ineffective and thus are not allowed.
  4. Search squadrons. Air search units on carriers may conduct a search mission within their range. They must operate as a squadron, and if they do contact an enemy they may be ordered to attack. Note that this is different than a cruiser search.
  5. Allied only search: Two searches within two areas of eastern edge. This reflects the presence of allied bases off the eastern edge of the map.
  6. Danger to search planes: If search planes fly in an area where there is CAP, there is a chance that they will be intercepted and destroyed.

Search Results

When serches are conducted and handed to the moderator, roll on the following to determine the search results:

Roll 2d6 for each search. If more than one task force is in an area, roll for each task force.

If task force is in an area searched by enemy planes:

If a random zone is needed, roll 1d10:

  1. = A
  2. = B
  3. = C
  4. = D
  5. = E
  6. = F
  7. = G
  8. = H
  9. = I
  10. = roll again

For random number of ships, roll 1d6 and add one.

To misreport ship types roll 1d10.

  1. = DD
  2. = CL
  3. = CA
  4. = CV
  5. = BB
  6. = DD
  7. = CA
  8. = CVL
  9. = AO
  10. = CL

Plane Movement

All planes have a specified range which indicates the total number of zones that they may move each turn. Planes must land before they use up their movement or they are lost. A player may purposely send planes on mission from which they cannot return.

Plane Ranges

Allied planes

F4F-3 Wildcat
SBD Dauntless
TBD Devastator
P-40 Airacobra
B-25C Mitchell
B-26A Marauder
B-17 Fortress
PBY Catalina
A-29 Hudson

Japanese planes

A6M2 (Zero)
D3A1 (Val)
B5N2 (Kate)
G4M1 (Betty)
H8K1 (Emily)
H6K5 (Mavis)
G3M2 (Nell)
F1M (Pete)
A6M2-N (Rufe)

Airbase Information

Each base is assigned a number of points and a set of structures that are present at the base.

Each turn five percent of the non runway, non AA points remaining can be used to repair damage to the base.These points can be used to repair the runway or other structures at the base. Repair can only occur if the base is not attacked during the turn (defined as fires its AA guns or takes at least one point of damage from bombing).

Seaplanes can land at any base that has not been completely destroyed OR they may use a sea plane tender after the tender has remained stationary for two turns in a zone with land and water present.

Runway Reduction

If the runway point total is reduced below the points noted below certain types of aircraft cannot use the field. Aircraft that are on missions from the base when the field is reduced below available limits may crash land at the base (with significant damage), or fly to another base if within range.

Placement of structures

Structures are placed by the defending player at the beginning of the tactical turn.

The runway must be a single straight line following a hex grid which at no point can be closer than four hexes from any board edge.

Hangers, repair buildings, headquarters, control tower, and mess hall must be within five hexes of the air strip. For sea plane bases, within five hexes of the landing area.

Barracks, warehouses, and oil tanks must be placed within ten hexes of the runway (or seaplane area). Oil tanks must be within one hex of each other.

Other structures may be placed where desired, except that no structure may be within three hexes of the board edge.

Each structure must occupy an identifiable hex.

Placement of structures may be changed each time the base is attacked.

Identification of structures

Structure saves versus bombing

Structure Level Dive
Light AA na 6
Heavy AA na 7
Small building 5 8
Medium building 5 9
Oil tank 6 10
Airfield 6 10
Large building 7 10

Base AA

Each base has an assigned numbed of AA emplacements, each with a factor of "3" or "1". Planes within 20 hexes/level of the base are rolled for with the total AA factor available at the base. Emplacements may be deployed anywhere on the base within the limits of structure placement, but not on any other structure.

Each AA emplacement has a set number of points (25 for "3" emplacements and 10 for "1" emplacements). These are not considered in calculating repair points, but repair points can be used to bring them up to strength, even if completely destroyed. When they fall below half of their total points the base AA is reduced by that emplacement's AA value.


Each base or carrier has a listed capacity limit.

Invasion Information

The major objective of the Japanese in this game is to capture Port Moresby. The only way this goal can be accomplished is by invading.

The Japanese may attempt to invade Port Moresby once per day turn. To successfully invade, the attacking player rolls 1d20. For every fifty points remaining to the Port Moresby runway add one to the die roll. If the number rolled is LESS THAN the number of transports present in the Port Moresby area, the invasion is successful. If any other number is rolled, one transport is lost. The IJN player IS NOT required to invade until ready.

Plane Repair

Planes that are damaged on missions can be repaired at either a base or on a carrier. For each turn a plane is marked HOLD one damage point can be removed. Three damage points can be removed every night turn.

Planes that are shot down or destroyed on missions or destroyed in strafing attacks have a forty percent chance of recovery. If at or over a friendly base there is a fifty percent chance of recovery. Recovered planes have all of their hit points to clear before they are back to full strength.

Planes lost due to running out of fuel and crashing are lost for the campaign.

Damaged planes may be ordered on missions. Search planes that are damaged must have at least 50% of their hit points to be able to conduct searches.

Aircraft Orders

During phase three, aircraft orders, planes may be given the following orders:

Orders are to whole squadrons except for fighters, which can be broken into smaller units, and search planes, which may be ordered individually.

Tactical games

When planes are placed to attack any target a tactical game begins.

Initial placement of ships, bases, and planes

Ship Placement

If CAP is present at the beginning of the game the attacker picks a ship that will be the main target of the attack. The attacker places the bow of this ship 1d20 hexes (minimum of five) from the center of the ship's board edge. The ship can be placed along any hex grid the attacker desires. The defending player then places the rest of the ships in the following order:

  1. Capital ships in the task force are placed, one at a time, anywhere in the set up zone and facing in any direction but no part of the ship can be within ten (10) hexes of any other ship.
  2. Auxiliary vessels are then placed, one at a time, anywhere in the set up zone and facing in any direction but no part of the ship can be within eight (8) hexes of any other ship.
  3. Finally, destroyers and smaller ships are placed, one at a time, anywhere in the set up zone and facing in any direction but no part of the ship can be within five (5) hexes of any other ship.

No ship may ever be placed where there is a possibility that any part of it would be off the board edge.

Once all ships are placed each is rolled for to determine its actual facing. Roll 1d6 for each ship. Keeping the bow of the ship in its original hex rotate the ship (if necessary) based on the die roll in the following pattern:

6 2
5 3

One (1) is directly away from the friendly board edge; Four (4) is directly toward the friendly board edge; 2, 3, 5, and 6 follow the appropriate hex grids.

If these rotations cause any two ships to collide (occupy the same hex), move the smaller ship directly away from the collision on its hex grid and both ships take 1d6 in damage.

If no CAP is present at the target the ships are deployed in the center of the board. The same procedure is used as in regular ship placement, but the target ship is placed d10 (no modifier) from the center hex, in either direction "1" or "4", by the attacking player. Other ships are set up with the normal restrictions but must all be within the twenty hex central zone.

Plane Placement

  1. No CAP at target:Attacking planesare placed anywhere on the table outside of AA range. Dive bombers can be placed at any level already in a vertical dive, if the player desires, and be assumed to have started their dive at high six. They may also start their dive on the table. Fighters are not required to enter AA zone.
  2. CAP present at target:
    1. Attack Coordination.

      -- Planes launched from the closest zone to the target will always attack first.

      • Launched from same zone Divide and number all flights launched from the same zone that are scheduled to attack. For each of these roll 1d6 and add the level speed of the slowest plane in the flight. The flight with the highest score will arrive first, as will any flights tied with it. For remaining flights roll 1d10, and subtract their level speed. This is the number of turns the flight must wait to enter the board. If the result is zero or less, the flight enters with the first flight(s).
      • Launched from different zones Roll 1d10, add the number of zones away from each other when the planes were launched, and subtract their level speed. Results of zero or less indicate that they join in the previous flight's attack, so roll for them as if they launched from the zone that flight started from. Otherwise they are considered a second attack and may only enter the table after the previous attack has concluded. When they do enter, roll for each flight as above.
      • Fighter coordination Sometimes fighters from one base will want to join bombers from another to coordinate their attacks. In these cases roll 1d10. A roll of 4 or more means they coordinate their attack and are rolled for as if they originated from the same zone. Otherwise they constitute a separate attack.

        Planes that were armed and on search missions are considered to have originated in the zone where they were ordered to search.

        The player may declare an abort for any flight and have it return to its base.

    2. Attacking player rolls 1d20 (minimum of 5) for each attacking formation. The lead element in that formation is placed that many hexes from anywhere on the friendly board edge. These can be in any legal formation at their declared altitude level.
    3. Once attacking planes are deployed, the defender rolls 1d20 for each intercepting section. Each section is placed AT LEAST that distance from all attacking planes, at their declared altitude level.
    4. The allied player may modify altitude of CAP by up to six levels from what had been declared if there is radar present at the target.

Island Bases

Bases are placed, centered on the friendly board edge, 10 hexes away from that edge, following the hex grid of the map.

Any planes on the ground at the base should be indicated by plane models of the type that is there.

Ready planes are placed on the runway. Other planes can be placed anywhere within five hexes of the runway, one plane per hex. Seaplanes should be placed next to a land area within five hexes of a building.

Any ships docked at the base should be placed within four hexes of the shore.

Actual base points are indicated by the airfield and structures located at the base. These are the targets of attack.

In no case can a potential target be placed within three hexes of any board edge.

Tactical Game

When all items have been placed the game begins. Each turn uses the following sequence, explained where needed below.

  1. Attempt to move ships. (If desired)
  2. Move all bomber squadrons and their escorts.
  3. Sequentially move hunters and interceptors.
  4. Attempt to take off ready fighters
  5. Conduct air to air combat.
  6. Conduct AA combat.
  7. Conduct any bombing or strafing.

Attempt to move ships.

Each turn the controlling player may attempt to alter the position of none, any, or all of the ships on the table.

For each ship you wish to move announce the ship and roll 1d10. A successful roll is a 10 or more for all ships except destroyers, which have a successful roll on a 9 or more.

When enemy planes are in AA range of a ship, the ship player my announce a violent maneuver and add two to the die roll. If this is done the violently maneuvering ship cannot fire its AA guns nor launch planes if a carrier.

A successful roll allows the ship to move in one of the following three ways:

If these movements cause any two ships to collide (occupy the same hex), move the smaller ship away from the collision and both ships take 1d6 in damage.

Ships may not leave the playing field.

No part of a ship may ever be off the table edge.

Ships that are reduced to "no move" may not attempt these actions.

End of Tactical game

The tactical turn ends, and all firing stops, when the last attacking plane drops its bomb.

Ship Rules

AA Fire

AA range is twenty hexes and/or levels (where each level counts as one hex).

For each plane in range of AA from any AA position or any part of a ship total the AA values of all firing positions or ships. This is the AA total.

When targets are within ten hexes or levels of an AA position or ship, its AA value increases by one.

Modify total AA if necessary:

For each target roll 1d20. Any roll equal to or less than the AA total causes a hit with the following exceptions:

AA total 2 hits 3 hits critical hit
6+ 2 1 --
11+ 2 or 3 -- 1
16+ 2 -4 -- 1
16+ 3 - 6 2 1
26+ 4 - 8 2 - 3 1
31+ 6 - 10 3 - 5 1 or 2
A twenty always misses.

Planes at Wavetop 1 or 2 may be protected by intervening ships. When a ship takes damage equal to or greater than its No AA number, it may no longer fire AA.

Bombing Results

Rebasing Planes

Planes may take off and land on different carriers or bases under the following restrictions:

Other Information

Ready planes on carriers: If ready planes are on a carrier, each level or dive bomb hit adds one die to the damage roll. Attacking fighters (only) may strafe planes on carrier decks.

Ready fighters (only) are placed on the deck or runway and may attempt to take off during the tactical turn. To attempt to do so roll 1d10 each tactical turn for each base or carrier that has ready fighters. If a "1" is rolled, one fighter is destroyed. If a "9" or "10" is rolled one fighter takes off and is placed, at wavetop one, on the hex at the end of the runway/deck and may move normally the next turn. Any other result means that the plane cannot take off during that tactical turn. All planes launched in this way are considered part of the same formation. The Allied player may also make five (5) attempts to launch ready planes before the Japanese arrive if there is radar present. Results other than "9" or "10" are ignored. Any plane launched in this way can move five turns during the time the enemy is placing the attacking flights.

Aces: Note all kills by fighters and bombers (a kill is an attacks that cause the destruction of a target). When a plane can claim three "kills", the pilot is considered an ace and receives benefits.

Bombers aces When a bomber has caused two ships to be sunk the bomber is an ace. In all future bombing attacks the ability to hit a target is one better (either adding or subtracting) than would otherwise be the case.

Damaged Ships and Carriers: Ships may not be repaired during the game. A carrier may carry a full complement of planes until it is reduced to "No Move" status. At this point any planes on the ship are lost, and none can land.

Attacking bases

  • Bombing

    Bombs must land on or next to a structure or runway hex to cause damage. Each airstrip hex or building has a value assigned to it that totals to the field's total points.

    • Dive Bombing May target planes to bomb, but does not count for reduction of airfield.
    • Level Bombing Bomb must land on or next to a structure or runway hex to cause damage.
  • Bombing Bases

    When attacking land bases a slightly different bombing procedure is used. The normal rules for hitting the target and saves are used, with the following alterations:

    If the target is hit:

    Roll the number of d6 as indicated by the bomb factor of the plane.

    1. The total rolled is the damage to the target.
    2. Total all matched dice in the roll (doubles, triples, etc.) And divide by six.
    3. . For each whole six in the result, all surrounding hexes take one point of damage.

    Example: A B25 drops eight bombs, rolling 1, 1, 1, 2, 3, 4 ,4, and 6. The target takes 22 points of damage. Matched dice (1s and 4s) total 11. There is one "whole six" in eleven, so the hexes surrounding the target hex each take one point of damage.

    If the target is missed or saves

    1. Bombing from wavetop level is a miss.
    2. Bombing from low level.
      • Roll 1d6 for the direction of the bomb drift, with a one being the direction the plane is facing, a two to the hex side to the right and so on in a clockwise manner.
      • Roll 1d10 for how many hexes the bombs drift along that hex grid.
      • If the impact point is on or next to a target or a parked plane, roll for target hit.
    3. Bombing from medium or high level
      • Roll 1d6 for the direction of the bomb drift, with a one being the direction the plane is facing, a two to the hex side to the right and so on in a clockwise manner.
      • Roll 1d20 for how many hexes the bombs drift along that hex grid.
      • If the impact point is on or next to a target or a parked plane, roll for target hit.
    4. These rules do not apply to dive bombers.

  • Bombing with sea planes Level bombing attacks by sea planes (PBY, Mavis, Emily) on any target must be from low altitude level only.

    Fighter sweeps

    Fighters can be ordered to "sweep" an area to take targets of opportunity. These are written as attack orders with one of the following specified:

    1. Overfly an enemy base to engage CAP or strafe aircraft on the ground at that base.
    2. Patrol in a specified area to attempt to intercept incoming aircraft.
    3. Provide CAP for a different zone.

    Attack forces passing each other:

    If two attacks are launched and the launch points are the target of both attacks there is a chance that the forces will meet each other in the air.

    1. Have both players indicate the level (wavetop, low, medium, or high) the attacking planes are flying.
    2. Have both roll 2d6. Results indicate whether the other flight is spotted. It is possible for one to spot and the other not ot spot.

      • 2 -- no spot
      • 3 -- same level
      • 4 --within 1 level
      • 5 -- within 2 level
      • 6 -- within 3 levels
      • 7 -- within 4 levels
      • 8 -- within 3 levels
      • 9 -- within 2 levels
      • 10 - within 1 level
      • 11 - same level
      • 12 - no spot

      If spotted and lying at the same level immediately go to tactical battle. If at different levels ask players if they want to do anything about it. If either do, go to tactical battle. Both set up in their own zones and must exit other edge to carry on with the attack. If planes leave the table on the edges they will return to their base.

    Victory Conditions

    As part of their expansion plans Japan needed to capture Port Moresby. To do so would have allowed them to cut communications between Australia and the United States and have given them a strong defensive perimeter. The Allies found out about this plan and were determined to stop it. Neither side, however, could afford to loose significant resources in this conflict. Especially valuable were the carriers.

    Based on this there are two areas where victory can be determined.

    1. Strategic.
      • If the Japanese capture Port Moresby within five days it would be a great strategic victory.
      • If the Allies prevent this capture it would be a strategic victory.

    2. Tactical
      Determine the number of enemy ship points lost, multiplying carrier points by five. Also determine the number of enemy aircraft lost for any reason, and permanently lost airbase points.
      • If outnumbered by more than three to one a great tactical victory.
      • If outnumbered by more than two to one a tactical victory.
      • If outnumbered by more than one to one a minor tactical victory.

      Any side that looses over 33% of its warship strength cannot claim any level of tactical victory.

  • Midway Suppliment

    These rules are easily converted to create a Midway Campaign. For the order of battle at Midway see Midway Order of Battle . For rule modifications see Midway Rules Modifications . For those that are truly gamers, the two campaigns (Coral Sea and Midway) can be combined, with surviving ships and carrier based planes from Coral Sea showing up at Midway -- and losses carrying over as well.

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