fighter_aircraft = {
    name = DOCTRINE_TRACK_FIGHTER_AIRCRAFT
    background = "GFX_air_superiority_bg"
    background_offset = -120
    icon = "GFX_doctrine_milestone_fighter_air"
    icon_frame = "GFX_doctrine_decor_fighter_aircraft_air"
    mastery = {
        multiplier = 5.0 # TODO - test the value
        equipment = {
            fighter
            interceptor
        }
    }
}

strike_aircraft = {
    name = DOCTRINE_TRACK_STRIKE_AIRCRAFT
    background = "GFX_battlefield_destruction_bg"
    background_offset = -40
    icon = "GFX_doctrine_milestone_striker_air"
    icon_frame = "GFX_doctrine_decor_strike_aircraft_air"
    mastery = {
        multiplier = 5.0 # TODO - test the value
        equipment = {
            cas
            naval_bomber
            suicide
        }
    }
}

medium_aircraft = {
    name = DOCTRINE_TRACK_MEDIUM_AIRCRAFT
    background = "GFX_operational_destruction_bg"
    background_offset = -15
    icon = "GFX_doctrine_milestone_medium_air"
    icon_frame = "GFX_doctrine_decor_medium_aircraft_air"
    mastery = {
        multiplier = 5.0 # TODO - test the value
        equipment = {
            tactical_bomber
            heavy_fighter
            scout_plane
        }
    }
}

heavy_aircraft = {
    name = DOCTRINE_TRACK_HEAVY_AIRCRAFT
    background = "GFX_strategic_destruction_bg"
    background_offset = -40
    icon = "GFX_doctrine_milestone_heavy_air"
    icon_frame = "GFX_doctrine_decor_heavy_aircraft_air"
    mastery = {
        multiplier = 5.0 # TODO - test the value
        equipment = {
            strategic_bomber
            maritime_patrol_plane
        }
    }
}

#####################################
# Victorian Air Era Tracks
#####################################

victorian_air_observation_track = {
    name = DOCTRINE_TRACK_VICTORIAN_AIR_OBSERVATION
    # background = "GFX_victorian_air_observation_bg"
    # icon = "GFX_doctrine_milestone_air_recon"
    # icon_frame = "GFX_doctrine_decor_air"
    mastery = {
        multiplier = 2.0
        sub_units = {
            balloon
            scout_plane
        }
    }
}

victorian_air_bombing_track = {
    name = DOCTRINE_TRACK_VICTORIAN_AIR_BOMBING
    # background = "GFX_victorian_air_bombing_bg"
    # icon = "GFX_doctrine_milestone_air_bomber"
    # icon_frame = "GFX_doctrine_decor_air"
    mastery = {
        multiplier = 2.0
        sub_units = {
            zeppelin
        }
    }
}

#####################################
# Machine Age Air Era Tracks
#####################################

machine_age_air_superiority_track = {
    name = DOCTRINE_TRACK_MACHINE_AGE_AIR_SUPERIORITY
    # background = "GFX_machine_age_air_superiority_bg"
    # icon = "GFX_doctrine_milestone_air_fighter"
    # icon_frame = "GFX_doctrine_decor_air"
    mastery = {
        multiplier = 2.0
        sub_units = {
            fighter
            heavy_fighter
        }
    }
}

machine_age_tactical_air_track = {
    name = DOCTRINE_TRACK_MACHINE_AGE_TACTICAL_AIR
    # background = "GFX_machine_age_tactical_air_bg"
    # icon = "GFX_doctrine_milestone_air_cas"
    # icon_frame = "GFX_doctrine_decor_air"
    mastery = {
        multiplier = 2.0
        sub_units = {
            cas
            tac_bomber
        }
    }
}

machine_age_strategic_air_track = {
    name = DOCTRINE_TRACK_MACHINE_AGE_STRATEGIC_AIR
    # background = "GFX_machine_age_strategic_air_bg"
    # icon = "GFX_doctrine_milestone_air_strat"
    # icon_frame = "GFX_doctrine_decor_air"
    mastery = {
        multiplier = 2.0
        sub_units = { strat_bomber }
    }
}

machine_age_naval_air_track = {
    name = DOCTRINE_TRACK_MACHINE_AGE_NAVAL_AIR
    # background = "GFX_machine_age_naval_air_bg"
    # icon = "GFX_doctrine_milestone_air_naval"
    # icon_frame = "GFX_doctrine_decor_air"
    mastery = {
        multiplier = 2.0
        sub_units = {
            nav_bomber
            cv_fighter
            cv_cas
            cv_nav_bomber
        }
    }
}