Divisions of up to three ships can be created. Currently divisions can only have one carrier (and a random team can have no more than two Carriers). As of patch 0.5.10, divisions are restricted to a one tier spread. A division with a Tier VI ship, for example, could include ships of Tier V and Tier VI, or Tier VI and Tier VII. Tier V, VI, and VII ships are not allowed in the same division at the same time.
Previously, there were no restrictions on division tiers, leading to "fail divisions" of high tier ships (such as Tier IX or X) divisioned with low tier ships (Tier I or II).
When placing divisions in a match, Match Maker will only consider the highest tier ship's Match Making tier range for purposes of tier placement. For example, a Tier 5's normal Match Making is +2/-1, so it will normally only see Tier 4 through Tier 7 ships in matches. Similarly, a Tier 6's normal Match Making is also +2/-1, so it will normally only see Tier 5 through Tier 8 ships in matches. When divisioned with ships of the same tier, the division will see the normal Match Making for that tier. For example, a division of only Tier 5s will only see matches with Tier 4 to Tier 7 ships. A division of only Tier 6s will only see matches with ships from Tier 5 to Tier 8.
However, when a division is made up of ships of unequal tier, only the top tier ship's tier range will be considered. Thus, let us say the Tier 5 and Tier 6 above form a division. Match Maker will only consider the Tier 6's tier spread. The Tier 6 can see Tier 8 matches, so the Tier 5 in the division with it will now also be subject to seeing Tier 8 matches where it normally would only be able to see Tier 7s max. This results in an effective +3/-1 Match Making spread for the Tier 5 when divisioned with a Tier 6. This is commonly called a "fail division" because this puts the lower tier ship in a battle tier they normally cannot see.
Ship Performance Factors
For each ship there are seven performance factors that provide a basis for comparison of any one ship against another in game. These performance factors are expressed on a relative scale of 0 (worst) to 100 (best). Each performance factor is based on the ship's abilities. Note that these factors are just a basis for comparison, and can change based on what modules, upgrades, or captain skills the ship is equipped with.
- Survivability is a measure of the ship's ability to take damage and keep fighting. Its mainly all about hit points. The T10 BB's IJN Yamato, KMS Großer Kurfürst, HMS Conqueror, USS Montana and MN Republique share top Survivability factor in-game with 100. Many tier one ships share the worst, with 4.*
- Artillery is a measure of the ship's firepower with its main and secondary guns. The main battery firing range in kilometers and the number, type, and positions of the main battery and the secondary armament guns contribute to this factor. The US T10 BB Montana, IJN Yamato and UK T10 BB Conqueror have the top Artillery factor in-game of 94. Asides tier 1 ships, The IJN T2 DD Tachibana has the worst with 2.
- AA Guns is a measure of the ship's anti-aircraft defences and its ability to defend itself from air attacks. The number and caliber of the on-board AA guns contribute to this factor. The U.S T10 CL Worcester has the best AA Guns factor in-game of 96. Many ships, such as the US premium T4 BB Arkansas Beta, IJN premium T2 DD Tachibana, Russian premium CA Oleg and KM T3 BB Nassau's A hull have the worst - 0 - because they are not armed with any AA Guns.
- Maneuverability factor is a measure of the ship's ability to maneuver, make turns, and maintain speed while turning. Three other factors affect Maneuverability, the ship's "Maximum Speed" in knots, its "Turning Circle Radius" in meters, and its "Rudder Shift Time" in seconds. The IJN T5 DD Minekaze and Russian T5 DD Podvoisky share the best Maneuverability factor in-game - 95. The US T4 CV Langley has the worst at 7.
- Concealment factor is a measure of the ship's ability to remain undetected by the enemy. The Concealment factor is a calculated parameter influenced by the ship's "Surface Detectability Range" and an "Air Detectability Range", each are also specified and expressed in kilometers. The IJN T2 DD Tachibana and it's T10 cousin Shimakaze has the best Concealment factor in-game of 98. The US T10 CV Midway has the worst at 5. Many camouflages, such as the Type-1 Camouflage further reduces the detectability range by sea of the ship it is mounted on by 3%.
- Torpedoes is a measure of the torpedo capability of those ships which carry torpedoes. The number, type, and position of the torpedo tubes and the range of the torpedoes contribute to this factor. The IJN T10 DD Shimakaze has the best Torpedo factor in-game of 60. The IJN T2 DDs Umikaze and Tachibana, as well as the USS Smith have the worst rating which is 4. Those ships not armed with torpedoes have no Torpedo factor.
- Aircraft is a measure of the aircraft capability of those ships which carry aircraft. The total number of squadrons, number of planes, and the type and capabilities of each of the planes: fighter, dive-bomber, or torpedo-planes; determine the Aircraft factor. The USA T10 CV Midway has the best in-game Aircraft factor of 86. Cruisers (beginning at T5 except the T4 IJN Kuma), and Battleships of certain tiers, carry 1 to 3 fighter/recon aircraft. Battleships can only mount catapult fighters at tier 7 and up, with the exception of Dunkerque. Only CVs have an Aircraft factor.