Move the start type requirement into ControlPoint.

game/commander/packagebuilder.py

@@ -43,9 +43,8 @@ class PackageBuilder:
         if assignment is None:
             return False
         airfield, squadron = assignment
-        if isinstance(airfield, OffMapSpawn):
-            start_type = "In Flight"
-        else:
+        start_type = airfield.required_aircraft_start_type
+        if start_type is None:
             start_type = self.start_type
 
         flight = Flight(

game/theater/controlpoint.py

@@ -670,6 +670,10 @@ class ControlPoint(MissionTarget, ABC):
         self._coalition = new_coalition
         self.base.set_strength_to_minimum()
 
+    @property
+    def required_aircraft_start_type(self) -> Optional[str]:
+        return None
+
     @abstractmethod
     def can_operate(self, aircraft: AircraftType) -> bool:
         ...
@@ -1106,6 +1110,10 @@ class OffMapSpawn(ControlPoint):
     def can_operate(self, aircraft: AircraftType) -> bool:
         return True
 
+    @property
+    def required_aircraft_start_type(self) -> Optional[str]:
+        return "In Flight"
+
     @property
     def heading(self) -> Heading:
         return Heading.from_degrees(0)

game/transfers.py

@@ -349,13 +349,17 @@ class AirliftPlanner:
         else:
             transfer = self.transfer
 
+        start_type = squadron.location.required_aircraft_start_type
+        if start_type is None:
+            start_type = self.game.settings.default_start_type
+
         flight = Flight(
             self.package,
             self.game.country_for(squadron.player),
             squadron,
             flight_size,
             FlightType.TRANSPORT,
-            self.game.settings.default_start_type,
+            start_type,
             departure=squadron.location,
             arrival=squadron.location,
             divert=None,