void UpdateAirplanesOnNewStation(const Station *st);

void UpdateAircraftCache(Aircraft *v, bool update_range = false);

void AircraftLeaveHangar(Aircraft *v, Direction exit_dir);

void AircraftNextAirportPos_and_Order(Aircraft *v);

void SetAircraftPosition(Aircraft *v, int x, int y, int z);

void GetAircraftFlightLevelBounds(const Vehicle *v, int *min, int *max);

template <class T>

int GetAircraftFlightLevel(T *v, bool takeoff = false);

/** Variables that are cached to improve performance and such. */