As a general statement, I feel that air forces in Shadow Empire are too immobile and clunky to deploy and redeploy, which in my opinion feels unrealistic. In Shadow Empire, it is very difficult to field an air force and keep it in touch with rapidly moving, fluid ground operations.
I suggest the following modifications to help address the issue.
Airbase Construction
Airbases take too long to build, making it difficult for even ultralight air forces to keep up with a fluid battle front. Keeping in mind that a turn is scaled to two Earth months, I propose reducing the build time for each air base level by one turn (see the figure below). Thus, an Airbase-I would take zero turns to construct, an Airbase-II one turn and so on. For the construction of an Airbase-1, construction costs would be paid immediately, and the airbase be instantly available for use. Remember, an Airbase Level 1 only supports ultralight aircraft (think WW1 biplanes, see figures below), and only needs to be constructed in an open field or meadow with some grading for runways and some tents for hangers. This sort of airbase can certainly be built far quicker than two months. Even in WW2 we see much quicker times for more advanced airfields: "During the peak constructional year of 1942, new airfields were becoming available at an average rate of one every three days..." (citation, page 4).
This is how I imagine an Airbase Level 1
This might be an Airbase Level 2
Air Range
Unlike ground units, air units should be “sortie based” and not movement-distance based. The range shouldn’t be how far it can move in a turn, but instead, reflect how much fuel it can hold in its tank for a single sortie.
The current air unit implementation treats air units like ground units in this regard limiting movement by range, reducing the range of an air unit if it has reduced action points and so on. This is not realistic since air units do not drive a linear distance to a new location like ground units do; they fly multiple times to a ranged location typically starting and finishing from a fixed spot, i.e., the airbase.
Instead of reducing an air units range based on AP, the number of sorties an air unit can perform at a given range (up to it’s maximum) should be reduced. This would be a better model of how air forces behave in reality.
Therefore, I propose a simple, player-intuitive way of modeling air unit missions and movements based on sorties follows: One AP is spent for each hex flown. For combat and recon missions, each hex flown in each combat/recon round (i.e., each sortie) costs one AP. For movement between airbases, one hex costs one AP.
A combat mission is capped at 10 rounds (i.e., 10 sorties). A recon mission is capped at 3 rounds.
Example 1: An air unit with a range of 8 hexes has a full 100 AP. It moves to an airbase 7 hexes away consuming 7 AP. It has 93 AP remaining. It moves again to an airbase 8 hexes away. It has 85 AP remaining. It could repeat this until it is out of AP. This simulates a more realistic way of strategically transferring or tactically rebasing air units. Only very rarely are air units crated up and packed onto trains or ships for strategic transfer. In addition, air units can rebase to another airbase then fly attack/recon missions from there with the remaining AP.
Example 2: An air unit with mission-range of 8 hexes has a full 100 AP. It could run an attack at an 8-hex range for 10 rounds (80 AP consumed). The air unit would have 20 AP left over. Note that it cannot exceed it’s 8 hex range. Nor can it run more than 10 rounds (sorties) in an attack mission.
Example 3: An air unit with a mission-range of 8 hexes has only 35 AP. It could run an attack at 8 hexes for just 4 rounds (32 AP required) and would have 3 AP left. Alternatively, it could run an attack at a 3-hex range for a full 10 rounds (30 AP) and have 5 AP remaining.
Bonus Points for Vic
