Fix client initialization issue with AirMap flight planning

src/MissionManager/PlanMasterController.cc

@@ -82,7 +82,8 @@ void PlanMasterController::start(bool flyView)
 #if defined(QGC_AIRMAP_ENABLED)
     //-- This assumes there is one single instance of PlanMasterController in edit mode.
     if(!flyView) {
-        qgcApp()->toolbox()->airspaceManager()->flightPlan()->startFlightPlanning(this);
+        // Wait for signal confirming AirMap client connection before starting flight planning
+        connect(qgcApp()->toolbox()->airspaceManager(), &AirspaceManager::connectStatusChanged, this, &PlanMasterController::_startFlightPlanning);
     }
 #endif
 }
@@ -271,6 +272,10 @@ void PlanMasterController::_sendRallyPointsComplete(void)
     }
 }
 
+void PlanMasterController::_startFlightPlanning(void) {
+    qgcApp()->toolbox()->airspaceManager()->flightPlan()->startFlightPlanning(this);
+}
+
 void PlanMasterController::sendToVehicle(void)
 {
     if (_managerVehicle->highLatencyLink()) {

src/MissionManager/PlanMasterController.h

@@ -111,6 +111,7 @@ private slots:
     void _sendMissionComplete(void);
     void _sendGeoFenceComplete(void);
     void _sendRallyPointsComplete(void);
+    void _startFlightPlanning(void);
 
 private:
     void _showPlanFromManagerVehicle(void);