Default turnaround for multi-rotor to 5 meters

src/MissionManager/SurveyMissionItem.cc

@@ -108,9 +108,10 @@ SurveyMissionItem::SurveyMissionItem(Vehicle* vehicle, QObject* parent)
 {
     _editorQml = "qrc:/qml/SurveyItemEditor.qml";
 
+    // If the user hasn't changed turnaround from the default (which is a fixed wing default) and we are multi-rotor set the multi-rotor default.
     // NULL check since object creation during unit testing passes NULL for vehicle
-    if (_vehicle && _vehicle->multiRotor()) {
-        _turnaroundDistFact.setRawValue(0);
+    if (_vehicle && _vehicle->multiRotor() && _turnaroundDistFact.rawValue().toDouble() == _turnaroundDistFact.rawDefaultValue().toDouble()) {
+        _turnaroundDistFact.setRawValue(5);
     }
 
     connect(&_gridSpacingFact,                  &Fact::valueChanged,                        this, &SurveyMissionItem::_generateGrid);