Military logistics

The present Simple Military Logistics Model would allow to simulate supply chain, thereby having increased importance of infrastructure, decrease in the troops efficiency at supply interruption and adds to game such military strategies and operations as:

• troop withdrawal and reinforcements,
  
• pincer movement and encirclement,
  
• strategic bombing.
  

I. Transportation of Troops

If two adjacent provinces have at least level 1 infrastructure, there is possible to send the troops between these provinces by railway rolling stock.

It could look similar to port operations and the movement on oceans:
a) loading and unloading is allowed only in the center of a province in a place of roads crossing.
b) loading and unloading takes time and depends from infrastructure level.
c) at the time of loading, unloading and in the movement units are very vulnerable.
d) all units that use rolling stock moving at the equal speed which depends on the level of infrastructure and doesn't depend on terrain type.

Table 1. Movement time from Warsaw to Turin by the current rules and on rolling stocks.



In the table are used the following values:
infantry speed (plain/urban/mountains): 25/25/19 kmh
med. armor speed (plain/urban/mountains): 30/24/12 kmh
armor car speed (plain/urban/mountains): 45/36/18 kmh
loading/unloading time (lvl1/lvl2/lvl3): 4.5/3.0/1.5 hours
speed on railway (lvl1/lvl2/lvl3): 50/70/90 kmh

As it is visible in the table, movement of troops by railway rolling stocks is expedient only on long distances, through mountain provinces or for low-speed units. To save time on loading and unloading it needs to build infrastructure in all provinces from start point to end point.

The destruction of infrastructure (for example by means of strategic bombing) in one of the provinces on route significantly increases the time of movement.


II. The Head Quarter

The Head Quarter (HQ) is a building that can be built in any province and it works

a) as the capital*:

• Moral penalty from distance to capital is calculated as distance to the nearest HQ,
  
• province receives bonus 25 points to target moral,
  

b) as hospitals and repair factories:

• units receive bonus 25 points to target moral.
  

*The capital city is quasi the first HQ.

Distance calculated as fastest route of infantry units to the HQ including moving by railway rolling stock.

HQ can be built in any province, but with each new HQ is increased transport costs, which reduce the production of resources in all provinces (like corruption in Supremacy). The penalty is calculated with the construction of a third HQ (capital and first HQ have no effect), grows linearly, and can not be more than 15%.


III. Supplies and Moral

If a province where the troops are stationed has a connection to the HQ, the troops get supplies and their Moral is restored to the level of province Moral. The more supplies, the faster the recovery.

How many supplies will be delivered to the troops depends:

• on the distance to the nearest HQ and
  
• on the province Moral where troops are stationed.
  

No Moral regeneration when the troops are stationed in a province where Moral is lower than the Moral troops.

The Moral troops is drop only in the case if delivery of supplies are completely absent.

Inasmuch as the Moral restoration in the provinces with the HQ is maximal, then the HQ operate as hospitals and repair factories. The withdrawal to the HQ helping troops recover from Moral injury faster.


IV. Encirclement

If the troops are isolated and a province where they are stationed don't has a connection to the HQ, that is, the troops are in the encirclement, they lose 25 points of Moral daily. When the Moral drops to 0 the troops surrendering and disappear from the battlefield.


Appendix

The Moral formula

Daily Moral regeneration:
dM = a * 2 ^ (-r/b) * (m + mb - M)/100

where
a = 15 - the maximum Moral regeneration for the day,
b = 24 - a distance (hours) from the HQ where Moral regeneration is reduced by half,
r - the distance (hours) from the HQ,
m - the Moral province,
mb = 25 in province with HQ and =0 in province without HQ, bonus to target moral,
M - the current morale of the troops.

Table 2. Daily moral recovery depending on the distance to the HQ and moral of the province where troops are stationed



Graph 1. Moral regeneration versus time (days) in a provine with Moral 100.



Graph 2. Moral regeneration versus time (days) in a provine with Moral 50.



Thank you for your likes and comments!

I would like to point out:

• algorithm to determine the fastest route for different segments of map (sea, with road infrastructure and without, loading and unloading) already exists and works perfectly.
  
• the distance to the HQ must be calculated for the province, and not for each unit separately. All units in the province will have the same daily morale regeneration. Because the distance to the capital is already calculated in the game (but never used), it does not significantly impact on performance.
  
• currently the distance penalty is not used in the game because its values are very large. Implementation of railway rolling stock would significantly reduce the time travel on the middle range, and the HQs on the long range. Therefore the penalty for distance to the capital (or to the HQ) could return in the game.
  
• we can not manipulate directly the strength of troops. The only way to change the troops strength is to change their morale.
  
• construction of infrastructure in the occupied provinces would finally acquire meaning.
  
• strategic bombers will gain its importance. The bombing of strategic targets such as infrastructure and transportation hubs (HQs) will be just as important an element of the strategy as it is in reality. Since the destruction of the strategic targets increases the distance to the HQ and therefore the province morale will decrease too, that has double impact on the troops morale regeneration.
  
• the withdrawal of troops to restore morale has the meaning only for very damaged troops, because the rate of morale recovery is very low for the troops with moral 80+. HQs could fix it. Troops fully restore morale in a few days when their place in the province with the HQ.
  

Don't forget that one day in game is equivalent to several real months.

How much time is required to force the encircled troops surrender you can found in Wikipedia (Salients, re-entrants and pockets).