Notes on Supply Sources and Supply Connections (updated to reflect changes in version 1.03)
General
1. Supply is a fundamental factor in the game. Supply affects units' combat effectiveness, Action Points, capacity for Operational Movement, reinforcement levels, vulnerability to desertion and attrition, as well as the cost to National Morale if they are destroyed and the cost in MPPs if they are then rebuilt. The supply levels of towns, cities and ports determines where units can be built and up to what level they can be reinforced and if units can use Operational movement though them.
2. Land, air and naval units all need supply. Most of the following rules apply specifically to land units. For the differences in the rules rules governing supply for air and naval units, see the relevant section below.
3. Supply for both players is calculated at the end of each turn. You can check the supply potentially available to your land units in every hex at the start of your turn by pressing the S key. If you press the S key again, it will recalculate what your supply would be in each hex next turn, taking into account any moves you have made so far and any automatic increases in the level of friendly supply sources.
4. Land units have three potential sources of supply: urban resource hexes; ports; or HQ units. Often land units can trace a supply line to more than one of these sources. A unit's supply level is determined by the highest value supply source which it can reach through a line of supply.
5. A line of supply is a line of contiguous friendly controlled hexes between a unit and a supply source. Enemy zones of control do not cut supply lines, but enemy controlled hexes do.
6. Each supply source has a supply range which depends on its current supply level and the number of Action Points required to move from the source to the units being supplied. Terrain costs thus can reduce the supply available to land units. If a supply line can be traced over a road hexside, it will negate the terrain effects of that hex (unless it is an unpaved road in Mud conditions).
7. An urban resource, a port or a HQ can supply an unlimited number of friendly land units within supply range. (There are different rules for air units - see below).
Supply from Urban Resources
8. The following are the maximum supply levels available from the following friendly controlled urban resources:
a) Major Capitals and Major Cities: 12
b) Cities, Fortresses and Fortified Towns: 10 (with some exceptions, see below)
c) Towns and Settlements: 8
Note that Cities in the Ottoman Empire and Serbia (namely Belgrade) have the same maximum supply value as towns, i.e 8.
9. Urban resources that have been captured from the enemy have their maximum supply levels reduced by an Occupational Efficiency factor. In the default campaign, this factor is set at 80% for most countries. This gives the following maximums for occupied urban resources:
a) Major Cities: 10
b) Cities, Fortresses and Fortified Towns: 8
c) Towns and Settlements: 6
The exceptions to the above are in Serbia, Montenegro, Albania and Greece, where the Occupational Efficiency factor in the default campaign is set at 100%. In these countries, there will be no reduction in the supply levels of their urban resources if occupied. Note that Syria, Palestine, Arabia and Mesopotamia all start the game as Ottoman occupied territories, so the occupational efficiency factor applies to their towns and Capitals connected by rail back to Constantinople, giving them a maximum supply value of 6.
10. An urban resource will only provide its maximum supply if it is connected by an unbroken line of friendly controlled rail hexes of any length to one of the following: a friendly Major's Capital, Industrial Center or Primary Supply Center. The rail line cannot pass through any urban resources with a supply level of less than 5.
11. The supply level available from any urban resource will be reduced to a maximum of 5 if any of the following conditions apply:
a) if it can trace a supply line over friendly controlled land hexes but not by rail to a friendly Major's Capital, Industrial Center or Primary Supply Center;
b) if it can only trace a supply line (by rail or land) to a Secondary Supply Center;
c) if it can only trace a supply line (by rail or land) to a Minor Capital;
12. If an urban resource is completely cut off by land from any of the above supply sources, its maximum supply level will be 3. This can happen if it is cut off from a supply source by enemy controlled or neutral hexes or by water hexes.
13. If the factors reducing the maximum supply of an urban resource no longer apply (e.g. if it has a rail link to a friendly Major Capital restored) the resource will increase its supply by 1 point a turn until it reaches its maximum. (This is the same rate as an urban resource will recover from attrition due to adjacent enemy units, combat damage or scorched earth effects).
Supply from Ports
14. Ports can also provide supply to land units. Since land units cannot occupy port hexes, a port's supply range starts from the friendly controlled land hexes adjacent to the port (which usually, but not always, includes an urban resource). Thus, a level 10 port provides level 10 supply to units in the adjacent land hexes, diminishing to zero over its supply range, just like an urban resource.
15. Port hexes provide supply to land units up to their maximum level provided that a supply line can be traced by rail from the port hex to a friendly Major Capital, Industrial Center or Primary Supply Center. The maximum level for Major Ports with such a rail connection is 12 and for regular Ports it is 10.
16. Major Ports and regular Ports that do not have a connection by rail to one the above friendly Major supply sources have their maximum level reduced to 5. (This is the reason why ports in Scandinavia, on islands in the Mediterranean, in North Africa, the Middle East and Canada all start the game at level 5).
17. Ports that have had their maximum level reduced by adjacent enemy units, combat damage or scorched earth will recover at the same rate as urban resources i.e. 1 point per turn.
18. Occupied ports will have their port levels reduced by the same Occupational Efficiency factor that applies to Urban Resources in that country.
19. The presence of an enemy naval or land unit adjacent to a port will block all supply to friendly land units from that port.
Supply from HQs
20. HQ units are also a source of supply. HQs take the supply they receive from their nearest supply source and then distribute it at a higher level to other units in their supply range. This supply distribution feature of HQs makes them especially valuable when your units are operating at or beyond the range of supply from friendly urban resources or ports.
21: You can see these two different supply values for an HQ if you click on it. The HQ's incoming supply level is listed first, followed in brackets by its supply distribution level. Thus, if a HQ unit has a supply of "5 (8)", its incoming supply is 5 and the supply it distributes is 8.
22. The maximum supply that a HQ distributes to other units depends on the strength of the HQ and its incoming supply. Full strength HQs distribute supply according to the following scale:
Incoming supply: 0 Distributed supply: 3
Incoming supply: 1 or 2 Distributed supply: 5
Incoming supply: 3 or 4 Distributed supply: 6
Incoming supply: 5 Distributed supply: 8
Incoming supply 6 up Distributed supply: 10
23. Under certain conditions, one HQ can boost the supply distributed by a second HQ that is within its supply range. Only two HQs can be linked this way to form a supply chain. Within a chain, the HQ with the lower command rating boosts the supply distributed by the higher rated HQ. (If you click on the HQ receiving a boost, the HQ providing the boost will be highlighted in yellow.) Supply boosting between two HQs applies:
a) If the first HQ has an incoming supply of 1 or 2 and the second HQ has an incoming supply of less than 3, then the second HQ will have its supply boosted to 5(6).
b) If the first HQ has an incoming supply 3 or more and the second HQ has an incoming supply of less than 5, then the second HQ will have its supply boosted to 5(8).
24. HQs increase the minimum level of supply they distribute with each increment of Logistics tech, regardless of their incoming supply or their strength. Thus, a HQ with Level 5 in Logistics Tech will always distribute at least level 5 supply to other units, even at partial strength and with an incoming supply of zero.
Supply for Air Units
25. Air units can receive supply from urban resources and ports just like land units. However, to receive supply from a HQ, an air unit must be attached to it. Air units which are not attached to a HQ that is in range are indicated by a red hatch beneath the unit. Air units which could receive a higher level of supply if attached to a different HQ in range are indicated by a purple hatch beneath the unit. Unattached air units, especially in low supply areas, can find themselves much less effective in combat than attached air units.
Supply for Naval Units
26. Naval supply is calculated differently from supply for land or air units. Naval units can only receive supply from friendly ports. Unlike land or air units, the amount of supply received by naval units does not depend on the strength of the port - a naval unit will be resupplied to level 10 by ending its turn on any friendly port. Ports can project supply to naval units at sea for a supply range of 10, with the value of the supply received diminishing by 1 for each hex distance from the port. If naval units move out of range of a friendly port their supply levels will not drop, except for Amphibious Transports which will have their supply reduced by 1 point for each turn that they are at sea. However, naval units will have their supply reduced by 1 point per turn if they move using naval cruise or they raid a convoy route. They will also lose 1 supply point per combat they engage in, whether in attack or defense.
Supply for Amphibious Landings
27. All units (except HQs) making an Amphibious landing disembark at the current supply level +1 of their respective Transports. HQs disembark with an incoming supply level of 5 plus their current Amphibious Warfare tech level. After their first turn ashore, all units (except HQs and Marines) must find a local source of supply or their supply will drop to zero. If they are disembarked with a HQ, it can serve as a friendly supply source for up to 5 turns, at a diminishing rate of 2 supply points per turn. Marines also retain their own supply after disembarking, at a diminishing rate of at 2 supply points per turn.
