diff --git a/src/MissionManager/MissionController.cc b/src/MissionManager/MissionController.cc
index 4461381442ac8c243ca047db108b466a4afaeb33..60bdb0bf83744f784ef8d0abb7d01636c77d6924 100644
--- a/src/MissionManager/MissionController.cc
+++ b/src/MissionManager/MissionController.cc
@@ -1053,9 +1053,9 @@ bool MissionController::readyForSaveSend(void) const
     return true;
 }
 
-bool MissionController::setTakeoffCommand(SimpleMissionItem &missionItem, Vehicle &vehicle)
+bool MissionController::setTakeoffCommand(SimpleMissionItem &missionItem)
 {
-    if (vehicle.fixedWing() || vehicle.vtol() || vehicle.multiRotor()) {
+    if (_controllerVehicle->fixedWing() || _controllerVehicle->vtol() || _controllerVehicle->multiRotor()) {
         MAV_CMD takeoffCmd = _controllerVehicle->vtol() ? MAV_CMD_NAV_VTOL_TAKEOFF : MAV_CMD_NAV_TAKEOFF;
         if (_controllerVehicle->firmwarePlugin()->supportedMissionCommands().contains(takeoffCmd)) {
             missionItem.setCommand(takeoffCmd);
@@ -1067,10 +1067,10 @@ bool MissionController::setTakeoffCommand(SimpleMissionItem &missionItem, Vehicl
     return true;
 }
 
-bool MissionController::setLandCommand(SimpleMissionItem &missionItem, Vehicle &vehicle)
+bool MissionController::setLandCommand(SimpleMissionItem &missionItem)
 {
-    MAV_CMD landCmd = vehicle.vtol() ? MAV_CMD_NAV_VTOL_LAND : MAV_CMD_NAV_LAND;
-    if (vehicle.firmwarePlugin()->supportedMissionCommands().contains(landCmd)) {
+    MAV_CMD landCmd = _controllerVehicle->vtol() ? MAV_CMD_NAV_VTOL_LAND : MAV_CMD_NAV_LAND;
+    if (_controllerVehicle->firmwarePlugin()->supportedMissionCommands().contains(landCmd)) {
         missionItem.setCommand(landCmd);
     } else
         return false;
diff --git a/src/MissionManager/MissionController.h b/src/MissionManager/MissionController.h
index 0ed16524d2ae17965082e8043bd0854bdfebfd71..a0c7246d524b6366a673592afda288f42cbf01da 100644
--- a/src/MissionManager/MissionController.h
+++ b/src/MissionManager/MissionController.h
@@ -151,9 +151,9 @@ public:
     bool readyForSaveSend(void) const;
 
     /// sets the command in missionItem to a land command
-    bool setLandCommand     (SimpleMissionItem &missionItem, Vehicle &vehicle);
+    bool setLandCommand     (SimpleMissionItem &missionItem);
     /// sets the command in missionItem to a takeoff command
-    bool setTakeoffCommand  (SimpleMissionItem &missionItem, Vehicle &vehicle);
+    bool setTakeoffCommand  (SimpleMissionItem &missionItem);
 
     /// Sends the mission items to the specified vehicle
     static void sendItemsToVehicle(Vehicle* vehicle, QmlObjectListModel* visualMissionItems);
diff --git a/src/Wima/WimaController.cc b/src/Wima/WimaController.cc
index 3e48f46c9e3cfeeb9d73637e6551fa2e08678a71..347ea82a9c86c4a72ba43a8fd82a066841745595 100644
--- a/src/Wima/WimaController.cc
+++ b/src/Wima/WimaController.cc
@@ -548,7 +548,7 @@ bool WimaController::calcNextPhase()
         qWarning("WimaController::calcNextPhase(): nullptr");
         return false;
     }
-    _missionController->setLandCommand(*landItem, *_masterController->controllerVehicle());
+    _missionController->setLandCommand(*landItem);
 
     // copy to _currentMissionItems
     for ( int i = 1; i < missionControllerVisuals->count(); i++) {
diff --git a/src/Wima/WimaPlaner.cc b/src/Wima/WimaPlaner.cc
index 5e2106d34054c1e0b592a95c5533c1fd4ef1bd6e..b2df41886b66c2e7343391d66457405fad9c09d4 100644
--- a/src/Wima/WimaPlaner.cc
+++ b/src/Wima/WimaPlaner.cc
@@ -17,8 +17,13 @@ WimaPlaner::WimaPlaner(QObject *parent)
     , _measurementArea      (this)
     , _serviceArea          (this)
     , _corridor             (this)
+    , _circularSurvey       (nullptr)
+    , _surveyRefChanging    (false)
 {
     connect(this, &WimaPlaner::currentPolygonIndexChanged, this, &WimaPlaner::recalcPolygonInteractivity);
+    connect(&_updateTimer, &QTimer::timeout, this, &WimaPlaner::updateTimerSlot);
+    _updateTimer.setInterval(250); // 250 ms means: max update time 2*250 ms
+    _updateTimer.start();
 }
 
 QmlObjectListModel* WimaPlaner::visualItems()
@@ -195,120 +200,33 @@ bool WimaPlaner::updateMission()
 
     // extract old survey data
     QmlObjectListModel* missionItems        = _missionController->visualItems();
-    CircularSurveyComplexItem* survey  = nullptr;
 
-    int surveyIndex = -1;
-
-    for (int i = 0; i < _missionController->visualItems()->count(); i++) {
-        survey = qobject_cast<CircularSurveyComplexItem*>(missionItems->get(i));
-        if ( survey != nullptr) {
-            surveyIndex = i;
-            break;
-        }
-
-    }
+    int surveyIndex = missionItems->indexOf(_circularSurvey);
 
     // create survey item if not yet present
-    if (surveyIndex < 0) {
-        // set home position to serArea center
-        MissionSettingsItem* settingsItem= qobject_cast<MissionSettingsItem*>(missionItems->get(0));
-        if (settingsItem == nullptr){
-            qWarning("WimaPlaner::updateMission(): settingsItem == nullptr");
-            return false;
-        }
-        // set altitudes, temporary measure to solve bugs
-        QGeoCoordinate center = _serviceArea.center();
-        center.setAltitude(0);
-        _serviceArea.setCenter(center);
-        center = _measurementArea.center();
-        center.setAltitude(0);
-        _measurementArea.setCenter(center);
-        center = _corridor.center();
-        center.setAltitude(0);
-        _corridor.setCenter(center);
-        // set HomePos. to serArea center
-        settingsItem->setCoordinate(_serviceArea.center());
-
-        // create take off position item
-        int sequenceNumber = _missionController->insertSimpleMissionItem(_serviceArea.center(), missionItems->count());
-
-        _missionController->setCurrentPlanViewIndex(sequenceNumber, true);
-        SimpleMissionItem* takeOffItem = qobject_cast<SimpleMissionItem*>(missionItems->get(missionItems->count()-1));
-        if (takeOffItem == nullptr){
-            qWarning("WimaPlaner::updateMission(): takeOffItem == nullptr");
-            return false;
-        }
-        takeOffItem->setCoordinate(_serviceArea.center()); //necessary, insertSimpleMissionItem does not copy coordinate (why?)
-
-
+    if (surveyIndex == -1) {
         _missionController->insertComplexMissionItem(_missionController->circularSurveyComplexItemName(), _measurementArea.center(), missionItems->count());
-        survey = qobject_cast<CircularSurveyComplexItem*>(missionItems->get(missionItems->count()-1));
+        _circularSurvey = qobject_cast<CircularSurveyComplexItem*>(missionItems->get(missionItems->count()-1));
 
-        if (survey == nullptr){
+        if (_circularSurvey == nullptr){
             qWarning("WimaPlaner::updateMission(): survey == nullptr");
             return false;
         }
-        survey->setRefPoint(_measurementArea.center());
-        survey->setAutoGenerated(true); // prevents reinitialisation from gui
-        connect(survey->deltaR(),               &Fact::rawValueChanged, this, &WimaPlaner::setDirtyTrue);
-        connect(survey->deltaAlpha(),           &Fact::rawValueChanged, this, &WimaPlaner::setDirtyTrue);
-        connect(survey->isSnakePath(),          &Fact::rawValueChanged, this, &WimaPlaner::setDirtyTrue);
-        connect(survey->transectMinLength(),    &Fact::rawValueChanged, this, &WimaPlaner::setDirtyTrue);
 
+        // establish connections
+        _circularSurvey->setRefPoint(_measurementArea.center());
+        _circularSurvey->setAutoGenerated(true); // prevents reinitialisation from gui
+        connect(_circularSurvey->deltaR(),               &Fact::rawValueChanged, this, &WimaPlaner::calcArrivalAndReturnPath);
+        connect(_circularSurvey->deltaAlpha(),           &Fact::rawValueChanged, this, &WimaPlaner::calcArrivalAndReturnPath);
+        connect(_circularSurvey->isSnakePath(),          &Fact::rawValueChanged, this, &WimaPlaner::calcArrivalAndReturnPath);
+        connect(_circularSurvey->transectMinLength(),    &Fact::rawValueChanged, this, &WimaPlaner::calcArrivalAndReturnPath);
     }
 
-    survey->surveyAreaPolygon()->clear();
-    survey->surveyAreaPolygon()->appendVertices(_measurementArea.coordinateList());
+    // update survey area
+    _circularSurvey->surveyAreaPolygon()->clear();
+    _circularSurvey->surveyAreaPolygon()->appendVertices(_measurementArea.coordinateList());
 
-    // calculate path from take off to opArea
-    if (survey->visualTransectPoints().size() == 0) {
-        qWarning("WimaPlaner::updateMission(): survey no points.");
-        return false;
-    }
-    QGeoCoordinate start = _serviceArea.center();
-    QGeoCoordinate end = survey->coordinate();
-
-#ifdef QT_DEBUG
-    if (!_visualItems.contains(&_joinedArea))
-        _visualItems.append(&_joinedArea);
-#endif
-
-    QList<QGeoCoordinate> path;
-    if ( !calcShortestPath(start, end, path)) {
-        qgcApp()->showMessage( QString(tr("Not able to calculate the path from takeoff position to measurement area.")).toLocal8Bit().data());
-        return false;
-    }
-    _arrivalPathLength = path.size()-1; // -1: last item is first measurement point
-    for (int i = 1; i < path.count()-1; i++) {
-        sequenceNumber = _missionController->insertSimpleMissionItem(path.value(i), missionItems->count()-1);
-        _missionController->setCurrentPlanViewIndex(sequenceNumber, true);
-    }
-
-    // calculate return path
-    start   = survey->exitCoordinate();
-    end     = _serviceArea.center();
-    path.clear();
-    if ( !calcShortestPath(start, end, path)) {
-        qgcApp()->showMessage(QString(tr("Not able to calculate the path from measurement area to landing position.")).toLocal8Bit().data());
-        return false;
-    }
-    _returnPathLength = path.size()-1; // -1: fist item is last measurement point
-    for (int i = 1; i < path.count()-1; i++) {
-        sequenceNumber = _missionController->insertSimpleMissionItem(path.value(i), missionItems->count());
-        _missionController->setCurrentPlanViewIndex(sequenceNumber, true);
-    }
-
-    // create land position item
-    sequenceNumber = _missionController->insertSimpleMissionItem(_serviceArea.center(), missionItems->count());
-    _missionController->setCurrentPlanViewIndex(sequenceNumber, true);
-    SimpleMissionItem* landItem = qobject_cast<SimpleMissionItem*>(missionItems->get(missionItems->count()-1));
-    if (landItem == nullptr){
-        qWarning("WimaPlaner::updateMission(): landItem == nullptr");
-        return false;
-    } else {
-        if (!_missionController->setLandCommand(*landItem, *_masterController->controllerVehicle()))
-            return false;
-    }
+    calcArrivalAndReturnPath();
 
     pushToContainer(); // exchange plan data with the WimaController via the _container
     setDirty(false);
@@ -524,6 +442,116 @@ void WimaPlaner::recalcPolygonInteractivity(int index)
     }
 }
 
+bool WimaPlaner::calcArrivalAndReturnPath()
+{
+    // extract old survey data
+    QmlObjectListModel          *missionItems   = _missionController->visualItems();
+
+    int surveyIndex = missionItems->indexOf(_circularSurvey);
+
+    if (surveyIndex == -1) {
+        qWarning("WimaPlaner::calcArrivalAndReturnPath(): no survey item");
+        return false;
+    }
+
+    // remove old arrival and return path
+    int size = missionItems->count();
+    for (int i = surveyIndex+1; i < size; i++)
+        _missionController->removeMissionItem(surveyIndex+1);
+    for (int i = surveyIndex-1; i > 1; i--)
+        _missionController->removeMissionItem(i);
+
+    // set home position to serArea center
+    MissionSettingsItem* settingsItem= qobject_cast<MissionSettingsItem*>(missionItems->get(0));
+    if (settingsItem == nullptr){
+        qWarning("WimaPlaner::calcArrivalAndReturnPath(): settingsItem == nullptr");
+        return false;
+    }
+
+    // set altitudes, temporary measure to solve bugs
+    QGeoCoordinate center = _serviceArea.center();
+    center.setAltitude(0);
+    _serviceArea.setCenter(center);
+    center = _measurementArea.center();
+    center.setAltitude(0);
+    _measurementArea.setCenter(center);
+    center = _corridor.center();
+    center.setAltitude(0);
+    _corridor.setCenter(center);
+    // set HomePos. to serArea center
+    settingsItem->setCoordinate(_serviceArea.center());
+
+    // set takeoff position
+    bool setCommandNeeded = false;
+    if (missionItems->count() < 3) {
+        setCommandNeeded = true;
+        _missionController->insertSimpleMissionItem(_serviceArea.center(), 1);
+    }
+    SimpleMissionItem* takeOffItem = qobject_cast<SimpleMissionItem*>(missionItems->get(1));
+    if (takeOffItem == nullptr){
+        qWarning("WimaPlaner::calcArrivalAndReturnPath(): takeOffItem == nullptr");
+        return false;
+    }
+    if (setCommandNeeded)
+        _missionController->setTakeoffCommand(*takeOffItem);
+    takeOffItem->setCoordinate(_serviceArea.center());
+
+    if (_circularSurvey->visualTransectPoints().size() == 0) {
+        qWarning("WimaPlaner::calcArrivalAndReturnPath(): survey no points.");
+        return false;
+    }
+
+    // calculate path from take off to survey
+    QGeoCoordinate start = _serviceArea.center();
+    QGeoCoordinate end = _circularSurvey->coordinate();
+
+    #ifdef QT_DEBUG
+    if (!_visualItems.contains(&_joinedArea))
+        _visualItems.append(&_joinedArea);
+    #endif
+
+    QList<QGeoCoordinate> path;
+    if ( !calcShortestPath(start, end, path)) {
+        qgcApp()->showMessage( QString(tr("Not able to calculate the path from takeoff position to measurement area.")).toLocal8Bit().data());
+        return false;
+    }
+    _arrivalPathLength = path.size()-1; // -1: last item is first measurement point
+    int sequenceNumber = 0;
+    for (int i = 1; i < path.count()-1; i++) {
+        sequenceNumber = _missionController->insertSimpleMissionItem(path.value(i), missionItems->count()-1);
+        _missionController->setCurrentPlanViewIndex(sequenceNumber, true);
+    }
+
+    // calculate return path
+    start   = _circularSurvey->exitCoordinate();
+    end     = _serviceArea.center();
+    path.clear();
+    if ( !calcShortestPath(start, end, path)) {
+        qgcApp()->showMessage(QString(tr("Not able to calculate the path from measurement area to landing position.")).toLocal8Bit().data());
+        return false;
+    }
+    _returnPathLength = path.size()-1; // -1: fist item is last measurement point
+    for (int i = 1; i < path.count()-1; i++) {
+        sequenceNumber = _missionController->insertSimpleMissionItem(path.value(i), missionItems->count());
+        _missionController->setCurrentPlanViewIndex(sequenceNumber, true);
+    }
+
+    // create land position item
+    sequenceNumber = _missionController->insertSimpleMissionItem(_serviceArea.center(), missionItems->count());
+    _missionController->setCurrentPlanViewIndex(sequenceNumber, true);
+    SimpleMissionItem* landItem = qobject_cast<SimpleMissionItem*>(missionItems->get(missionItems->count()-1));
+    if (landItem == nullptr){
+        qWarning("WimaPlaner::calcArrivalAndReturnPath(): landItem == nullptr");
+        return false;
+    } else {
+        if (!_missionController->setLandCommand(*landItem))
+            return false;
+    }
+
+
+    return true;
+}
+
 bool WimaPlaner::recalcJoinedArea(QString &errorString)
 {
     // check if area paths form simple polygons
@@ -652,6 +680,30 @@ void WimaPlaner::setDirtyTrue()
     setDirty(true);
 }
 
+void WimaPlaner::updateTimerSlot()
+{
+    // General operation of this function:
+    // Check if parameter has changed, wait until it stops changing, update mission
+
+    // circular survey reference point
+    if (_circularSurvey != nullptr) {
+        if (_surveyRefChanging) {
+            if (_circularSurvey->refPoint() == _lastSurveyRefPoint) { // is it still changing?
+                calcArrivalAndReturnPath();
+                _surveyRefChanging = false;
+            }
+        } else {
+            if (_circularSurvey->refPoint() != _lastSurveyRefPoint) // does it started changing?
+                _surveyRefChanging = true;
+        }
+    }
+
+
+    // update old values
+    if (_circularSurvey != nullptr)
+        _lastSurveyRefPoint = _circularSurvey->refPoint() ;
+}
+
 QJsonDocument WimaPlaner::saveToJson(FileType fileType)
 {
     /// This function save all areas (of WimaPlaner) and all mission items (of MissionController) to a QJsonDocument
diff --git a/src/Wima/WimaPlaner.h b/src/Wima/WimaPlaner.h
index c03855d0ce0543ec2674c4bd24bf76ca0b053d9c..85f12b22372a21a6e98f98ffd13434a3a70d78d9 100644
--- a/src/Wima/WimaPlaner.h
+++ b/src/Wima/WimaPlaner.h
@@ -122,10 +122,12 @@ signals:
 
 private slots:
     void recalcPolygonInteractivity (int index);
+    bool calcArrivalAndReturnPath   (void);
     bool recalcJoinedArea           (QString &errorString);
     void pushToContainer            ();    
     void setDirtyTrue               ();
-
+    // called by _updateTimer::timeout signal, updates different mission parts, if parameters (e.g. survey or areas) have changed
+    void updateTimerSlot            ();
 private:
     // Member Functions
     WimaPlanData toPlanData();
@@ -145,4 +147,10 @@ private:
     WimaCorridor            _corridor; // corridor connecting _measurementArea and _serviceArea
     int                     _arrivalPathLength; // the number waypoints the arrival path consists of (path from takeoff to first measurement point)
     int                     _returnPathLength; // the number waypoints the return path consists of (path from last measurement point to land)
+
+    CircularSurveyComplexItem* _circularSurvey; // pointer to the CircularSurvey item in _missionController.visualItems()
+
+    QTimer                  _updateTimer; // on this timers timeout different mission parts will be updated, if parameters (e.g. survey or areas) have changed
+    QGeoCoordinate          _lastSurveyRefPoint;
+    bool                    _surveyRefChanging;
 };