Fuel/Supply Tracking

From SEOW Wiki (EN)
Jump to: navigation, search

What is supply?

In SEOW, we use the word "supply" to represent all materials, services and logistics required by any unit to maintain a state of mobile combat readiness. Thus "supply" represents an amalgam of fuel, ammunition, medicine, food, radio support, maps, clothing etc. Units "in supply" are able to manoeuvre and fight; units "out of supply" become immobile and passive. If a unit stays out of supply long enough, it will eventually either "desert" (i.e. destroy its weapons and vanish into the landscape) or "surrender" (destroy its weapons and march into captivity forever).

Simply for convenience, supply is measured in litres and is often referred to as "fuel". We deem that any object's maximum supply capacity is equal to its fuel tank capacity in litres. For example, a Ba-10 armoured car has a fuel tank capacity of 60 litres so its maximum supply requirement is 60 litres, while a bicycle has a supply capacity of 12 litres. You will find a complete list of fuel capacities inside the Object_Specifications table of SEDB31. The terms "supply" and "fuel" are interchangeable in SEOW. Running out of fuel is identical to running out of supply; being refueled is identical to being resupplied.

What units use supply?

All units in SEOW use supply at all times, no matter whether they are immobile, mobile or in combat. Of course, the rate of supply usage is different according to the unit status. Immobile units have a low rate of supply usage, while mobile units have a higher rate. Even units being freighted still use supply! The good news is that the supply loads carried by all units, all industrial facilities and all airbases are tracked automatically by SEOW down to the last litre - all commanders are responsible for is making sure that supplies reach the units that need them in good time. Sounds easy, eh? Wink

But the devil is in the detail. Commanders must schedule explicit movements of freighters/transports to load, ferry and drop off supplies. Of course, not all units can carry freight, so suddenly we see that transport ships, vehicles and aircraft become very high-value targets. In this sense, a P.11C can be as effective at tank-killing as an IL-10. All the P.11C has to do is strafe the fuel trucks that are resupplying the enemy tanks. Without supplies the enemy tanks will soon grind to a halt, stop shooting and then desert or surrender.

Also, from SEOW 3.2.4 onwards, some freight units can ONLY carry supply and nothing else. Examples include fuel trucks and tanker ships. This characteristic is governed by the "Supply_Only" field in the Object_Specifications table.

OK, enough generalities, let's see how all this works in SEOW v3.x.

DCSv3.1.0 Supply Tracking Support

Fuel/Supply tacking is turned on using the DCS tool; the option is under the Supply tab:


Clicking the topmost checkbox "Enable Fuel Supply Tracking" makes all the settings below visible. First there a two global settings. The "Global fuel consumption rate" is a number that multiplies all calculations of fuel consumption for all units on the map. Values greater than 1.0 mean that supply is used more rapidly than normal, while values less than 1.0 means that supply is used less rapidly. In the image above, the value is set to 1.6.

The "Supply Conversion Factor" is a number that expresses a single freight weight point as the equivalent number of litres of supply; set to 10000 litres in the image above. For example, a tramp steamer which has a default freight carrying capacity of 32 freight weight points could be used to carry 32x10000 = 320000 litres of supply with this setting.

Then follow two Morale settings that are used at the initialization stage. Morale is entwined in the supply model. Unit morale states are Excellent, Good, Average, Poor, Desperate. If a unit runs out of supply, its morale will drop down a level per mission. If a unit is resupplied it morale will climb one level each time it is resupplied. The presence of morale-influencing units (medium and heavy flak, command cars, civilians) can also assist or hinder morale state. Any unit that drops to Desperate morale state is in danger of desertion or surrender, depending on proximity of enemy units.

Underneath that is the "Fuel Supply Initials" panel. This panel contains settings that are used to specify the initial supply holdings in all units and facilities on the map, for each side. For each side there is a "Fuel Reserves" slider which determines the initial volume of supply held offmap for each side. These reserves can be transported onto the map using freight transportation units (ships, vehicles, aircraft) according to their individual freight capacities. Players cannot "buy" more fuel reserves! Then there is a slider for Initial Unit Fuel Load, a percentage value which is applied to each unit's maximum fuel capacity to determine the initial fuel holding in litres for each unit. Template initialization can lead to industrial installations being controlled by either side, or left as neutral. Sliders are provided for determining the initial Infrastructure Fuel Load of fuel installations, based on the maximum capacity multiplied by the slider percentages. The same sliders are used to determine initial airbase fuel holdings according to initial national control.

OK, that is how you set up your campaign to use supply tracking. All these sliders and settings need to be configured BEFORE loading your campaign template.

For advanced campaign designers, there is a new table in the database called Sector_Movement_Cost. This table specifies individual movement costs for each sector and season (summer/winter) for sea and ground movement types. For example, winter sea movement in Murmansk is, by default, 2.5 times more demanding on fuel than summer sea movement. Campaign designers can edit the values in this table according to their scenarios, but there is no interface for adjusting these parameters inside the DCS - a database edit is required.

Now let us see how this translates on the map once the campaign is initialized. In the following discussion, and for the sake of discussion, I will show unit icon morale and supply states that have been adjusted to what would have been generated by the settings in Part 2.

Modified Unit Icons in Supply Tracking Mode

Here is a close up view of Russian units at Prokhorovka.


Reading from left to right, we see an armoured train, a SU-76 SP Gun platoon, a T-70 tank platoon, a T-34 tank platoon, two transport columns and an engineers platoon. Most of the icons have coloured borders. These borders signify attributes of the platoons, as follows:

No Border: A normal unit with fuel state better than 30% of its full capacity. Orange Border: A unit with less than 30% of its fuel capacity. White Border: A unit completely out of supply. Green Border: A morale-influencing unit, capable of boosting the morale of other friendly units within the normal control radius.

The orange border grows in thickness as the supply level of the unit declines. Here is the unit tooltip for the SU-76 platoon (orange border):


With Supply Tracking enabled, we now see the unit's full supply state, its endurance with the current movement cost settings and its morale state.

Compare this with the tooltip for the T-70 platoon (white border):


Clearly this platoon is out of fuel, is immobilized and will need 4x480 = 1920 litres to completely resupply the platoon. Thankfully, its morale is still Average, so it will be at least 2 more missions before the T-70 platoon has a chance of deserting.

Finally, let's look at the first supply column's tooltip:


We can see that it has a Morale Influence rating of +1, which means that it adds +1 to every nearby friendly unit's morale at the end of each mission. It is also carrying 70% of its own supply needs. As a transportation unit it can carry up to 8 transportation points or up to 80000 litres of fuel supply. Presently it is transporting no freight at all.

This is the basic set of unit status information introduced to the MP as part of the Supply Tracking feature, and it applies to all ground and sea objects. Aircraft do not display the supply borders etc, since they are deemed to exhaust their allocated fuel loads at the end of each mission. Aircraft fuel loads are drawn from their Airbases automatically - it is up to flight commanders to ensure that Airbases are refueled to maintain active flight capacity.

Transporting and Unloading Fuel Supplies

Commander will necessarily become proficient at moving supplies around their maps. The alternative is unthinkable. Let's look at air freight of supplies first. Use the Logistics:Freight Tool (see below). Select your air transport flight, e.g. a Ju-52. Select the local airbase fuel supply and hit "Load Selected Freight". Choose the amount of fuel you want to load and then hit OK.


When your map is refreshed, your fuel load will be reflected in your air transport flight tooltip. You can now task your air transport to either fly the supplies to another airbase, where it can be unloaded to the new airbase fuel reserves, or you can order the transport flight to perform a Supply Drop anywhere on the map. This is done similarly to issuing a GATTACK waypoint - instead of selecting "G" as the waypoint directive, use "S" (available only for freight aircraft). If the air transport makes it to the supply drop location, the drop is assumed to be successful and a Supply Drop icon will appear on the map, as shown below:


Once discovered, Supply Drops can be targeted and destroyed by enemy units, but either side can use the supplies inside them. Basically any unit that is within the normal control radius can make use of the supplies, including scavenging enemy and friendly units at the same time. Freight units on both sides can pick up supplies from Supply Drops and transport them elsewhere.

Of course, ground and sea freight transport units can pick up supplies and move them around, and unload them too. Ground transporters can pick up supplies from fuel tanks, airbases and Supply Drops. Ship transporters can pick up fuel from fuel tanks. Normal ground units will automatically take supplies from nearby airbases, fuel tanks, Supply Drops and resupply points. Ships will take supplies from ship supply points, fuel tanks and freight tankers carrying supply.

Aircraft Fuel Supplies

As mentioned earlier, aircraft will take fuel from airbase reserves (or off map reserves if the flights are based off map) according to the fuel load specified by the flight commander. If Enforce_Aircraft_Loadouts is OFF, human pilots may choose their own fuel load at hosting time. SEOW will capture the fuel load actually used by pilots and decrement the airbase reserves accordingly. Droptank loads are also detected. If your airbase runs out of fuel, the airbase tooltip header will turn white, and ALL flights at that base will be grounded until new supplies arrive, either by air or ground. Here is a picture of an airbase out of supply:


You will see that the ground units carry their own supplies, so they are still active, but the aircraft are completely empty at the end of each mission. The status "ready" means they are ready for tasking but are yet to be "bombed up" for the next sortie.

The point of this SEOW feature is to make a realistic wartime environment. Now, all vehicles, ships and aircraft have critical roles to play. Ambulances, radio trucks and staff cars influence morale. Trucks and steamships carry supplies, Dakotas and Ju-52s can drop supplies to forward units or even to partisans behind the lines. A single light machine gun can destroy a supply platoon, thereby rendering an airbase inoperative or halting an armoured advance. I wish you all many hours of engrossing fun as you battle the enemy and the tyranny of long supply routes!

Two Consumption Modes: Mobile and Stationary

Disregarding aircraft, all other units are either mobile or stationary. Mobile units use their supplies faster than stationary units. First we look at stationary units.

Stationary Unit Supply Use

SEOW determines the amount of supply used per mission according to the class of unit, using the following hard-coded table:

Unit Class: Percentage of Supply Capacity Used per Mission
Artillery: 10%
Engineer: 10%
Aircraft: 5%
Ship: 3%
Armour: 15%
Vehicle/Mechanized: 10%
Other: 3%

For example, consider a single PzIIG tank. This has supply capacity of 320 litres, so if it was idle during a mission it would be deemed to consume 0.15*320 = 48 litres during that mission. That might seem a little high, but remember the supply quantity includes ammunition, food, fuel, medicines etc. SEOW cannot know whether the tank is engaged or not during a mission (unless it actually destroys something or is destroyed). It is possible the tank could be shooting at several targets without hitting anything. So the above idle usage rate is meant to average out over all platoons throughout the battle to give commanders a real need to resupply their units.

The actual rate of consumption can also be modulated using the "Global Fuel Consumption Rate" setting discussed in the first post of this thread. If you want to halve the above idle usage rates across the board, then set the "Global Fuel Consumption Rate" to 0.5.

Mobile Unit Supply Use

The other mode is where the unit is actually moving. In this case, SEOW determines how far the unit moves in the mission, expresses this as a fraction of the maximum endurance range of the unit. This fraction then gives us the proportion of the supply capacity of the unit that is consumed during the mission.

Let's use a M8 Greyhound as an example. The Greyhound has a fuel capacity of 150 litres and a maximum range of 200 km. Assume that in a mission, the Greyhound starts with a full fuel tank and then moves 20 km before stopping. That 20 km is 10% of its maximum endurance range, so we say that the Greyhound has used 10% of its supplies in moving that far, i.e. 15 litres. So at the end of the mission, SEOW analyzes the movement and sets the Greyhound fuel state to 150-15=135 litres (90%).The value of "Global Fuel Consumption Rate" is also applied to these fuel estimates: if "Global Fuel Consumption Rate" = 1.0, then the values above are exact. But other values for "Global Fuel Consumption Rate" cause the above calculations to change. If "Global Fuel Consumption Rate"=2.0, e.g., then the Greyhound will use twice as much fuel making the 20 km trip.

Advanced Movement Costs

OK, that all makes sense, but it really is a simple case. SEOW allows a lot more flexibility in determining how hard it is to move in combat sectors. Campaign designers have the ability to specify movement costs for each sector. Movement costs varying between summer and winter, and between sea and ground movement, as set by in the Sector_Movement_Cost table of the database. These cost factors are used in the same way as "Global Fuel Consumption Rate", i.e. to multiply the net fuel usage for each trip. E.g., this allows campaign admins to specify that sea movement in near Murmansk is 5 times more costly in winter than in summer, or that ground movement in Cyrenaica is the same cost all year round. Furthermore, the movement costs are nation-specific, so it is perfectly possible to specify that for a winter Stalingrad campaign, the Axis forces expend twice as much fuel per kilometre as the Allied forces.

The practical aspects / How to resupply your forces

This article has covered the theory of fuel/supply tracking in SEOW. If you want to learn more about the practical aspects, have a look at How to resupply your forces.