Practical Knowledge

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Practical knowledge is a concept that represents the nation's experience in engineering and construction of each particular field. Increasing practical knowledge is done only through production. Otherwise, practical knowledge will decay over time. Practical knowledge has two effects in game:

  • Modify research time (for technology that depends on practical knowledge)
  • Modify the time it takes to produce units

Effects on Production

Practical knowledge affects the time and cost of producing things. It is not a linear function; that is, having a practical of 50 does not reduce building time and cost by 50%. It is approximately defined by a piecewise linear function with the following segments:

From To Bonus per practical
Practical Bonus Practical Bonus
0 -50% 5 0% 10.00%
5 0% 6 5% 5.00%
6 6.25% 13 15% 1.25%
13 14.2% 25 ~23.3% ~0.8%
25 ~23.3% 90 48.8% ~0.4%
90 ~46.4% 99 48.6% ~0.2%

The chart below illustrates the effect of practical on production.


An approximate fit would be:

  • Linear regime (below 5 Practical): +10% time and IC per point below 5.
  • Square root regime (above 5 Practical): Time and IC reduction of 5% * sqrt(Practical - 5).

Therefore, a practical value of 0 means that the time and IC cost to produce something increases by 50%. Meanwhile, a practical value of 10 creates an ~11% reduction in the time and IC cost.

Practical Knowledge Table

By taking a quick look at the table, one can see that the game designers intended for most costs to be around 1,000 IC-days per practical. For those fields that do not fit this norm, one can see that the designers strove for all units in that category to have the same cost. Some fields, due either to low cost across the board or to low cost in a single unit, are easier to acquire experience in.

The easiest fields are Militia and Rocket, being about half of the 1,000 IC-days baseline cost. Massive construction of Flying Bombs and Garrisons will lead to an enormous explosion of practical, quickly cutting production time and cost. Rocket Artillery is also a relatively cheap way of increasing Artillery Practical, being significantly cheaper than the next cheapest artillery unit in terms of IC-days per practical. Interceptor squadrons are the quickest way to increasing Light Aircraft practical. Motorised Infantry is somewhat cheaper than the next most costly unit in the Mobile Unit field. Aside from these few examples, all other fields are relatively balanced.

Unit/Building Type Cost in IC-days Practical Type
Armor 1,005.9 Armor
H-Armor 1,008 Armor
SH-Armor 1,088.89 Armor
Light-Armor 1,008 Armor
Rocket Artillery 845.5 Artillery
Artillery Brigade 1,000 Artillery
AT 1,000 Artillery
AA (brigade) 1,106.75 Artillery
Tank Destroyer 1,125 Artillery
SP-Artillery 1,142.86 Artillery
SP Rocket Artillery 1,154.67 Artillery
Anti-air 1920 Artillery
Battlecruiser 972.97 Capital Ship
SH-Battleship 997.5 Capital Ship
Battleship 997.16 Capital Ship
Escort Carrier 984.38 Carrier
Carrier 1,102.94 Carrier
Industry 2,723.88 Construction
Naval base 2,727.27 Construction
Coastal Fort 2,727.27 Construction
Land Fort 2,727.27 Construction
Air base 2,769.23 Construction
Infrastructure 2807 Construction
Light Cruiser 1,050 Cruiser
Heavy Cruiser 1,050 Cruiser
Destroyer 1,000 Destroyer
Radar Station 720 Electrical
Strat Bomber 1,000 Heavy Aircraft
Transport plane 1,000 Heavy Aircraft
Infantry 1,106.75 Infantry
Mountain 1,335 Infantry
Paratrooper 1,500 Infantry
Engineer 1,540 Infantry
Marine 1,600 Infantry
Rocket Interceptor 1,428.57 Jet Engine
HQ 1,200 Land Doctrine
CAS 990 Light Air
Multi-role Fighter 1,071.43 Light Air
CAG 1,400 Light Air
Interceptor 840 Light Air
Naval Bomber 993.55 Medium Aircraft
TAC Bomber 1,005.71 Medium Aircraft
Garrison 501 Militia
Militia 665 Militia
Military Police 900 Militia
Motorised Infantry 934 Mobile Unit
Mechanized Infantry 1,000 Mobile Unit
AC 1,009.25 Mobile Unit
Cavalry 1,100 Mobile Unit
Nuclear(reactor) 9,000 Nuclear
Flying Bomb 600 Rocket
Flying Rocket 1,200 Rocket
Submarine 1080 Submarine
Nuclear sub 1,422.22 Submarine
Transport 900 Transport
Rocket 3,600 Rocket