diff --git a/src/blackcore/vatsim/networkvatlib.cpp b/src/blackcore/vatsim/networkvatlib.cpp
index e3ed9efb2..0b2f4f83e 100644
--- a/src/blackcore/vatsim/networkvatlib.cpp
+++ b/src/blackcore/vatsim/networkvatlib.cpp
@@ -795,7 +795,7 @@ namespace BlackCore
             const CCallsign callsign(callsignChar, CCallsign::Aircraft);
             CAircraftSituation situation(
                 callsign,
-                CCoordinateGeodetic(position->latitude, position->longitude, 0.0),
+                CCoordinateGeodetic(position->latitude, position->longitude), // geodetic height -> null
                 CAltitude(position->altitudeTrue, CAltitude::MeanSeaLevel, CLengthUnit::ft()),
                 CHeading(position->heading, CHeading::True, CAngleUnit::deg()),
                 CAngle(position->pitch, CAngleUnit::deg()),
diff --git a/src/blackmisc/aviation/aircraftsituation.cpp b/src/blackmisc/aviation/aircraftsituation.cpp
index f73f1e173..63e0a02c2 100644
--- a/src/blackmisc/aviation/aircraftsituation.cpp
+++ b/src/blackmisc/aviation/aircraftsituation.cpp
@@ -162,7 +162,7 @@ namespace BlackMisc
 
         bool CAircraftSituation::isOnGroundGuessed() const
         {
-            CLength heightAboveGround(this->getHeightAboveGround());
+            const CLength heightAboveGround(this->getHeightAboveGround());
             if (!heightAboveGround.isNull())
             {
                 return heightAboveGround.value(CLengthUnit::m()) < 1.0;
@@ -172,7 +172,7 @@ namespace BlackMisc
             if (qAbs(this->getPitch().value(CAngleUnit::deg())) > 10) { return false; }
             if (qAbs(this->getBank().value(CAngleUnit::deg())) > 10)  { return false; }
 
-            if (this->getGroundSpeed().value(CSpeedUnit::km_h()) > 80) { return false; }
+            if (this->getGroundSpeed().value(CSpeedUnit::km_h()) > 75) { return false; }
 
             // not sure, but this is a guess
             return true;
@@ -186,9 +186,10 @@ namespace BlackMisc
                 // we have a sure value
                 return this->getAltitude();
             }
-            if (!m_position.geodeticHeight().isNull() && !m_altitude.isNull())
+            const CLength gh(geodeticHeight());
+            if (!gh.isNull() && !m_altitude.isNull())
             {
-                return m_altitude - m_position.geodeticHeight();
+                return m_altitude - gh;
             }
             return notAvialable;
         }
diff --git a/src/blackmisc/geo/coordinategeodetic.cpp b/src/blackmisc/geo/coordinategeodetic.cpp
index eba2c600c..17a52cc85 100644
--- a/src/blackmisc/geo/coordinategeodetic.cpp
+++ b/src/blackmisc/geo/coordinategeodetic.cpp
@@ -190,13 +190,19 @@ namespace BlackMisc
             }
         }
 
-        CCoordinateGeodetic::CCoordinateGeodetic(CLatitude latitude, CLongitude longitude, BlackMisc::PhysicalQuantities::CLength height) :
+        CCoordinateGeodetic::CCoordinateGeodetic(CLatitude latitude, CLongitude longitude, BlackMisc::PhysicalQuantities::CLength geodeticHeight) :
             m_x(latitude.cos() * longitude.cos()),
             m_y(latitude.cos() * longitude.sin()),
             m_z(latitude.sin()),
-            m_geodeticHeight(height)
+            m_geodeticHeight(geodeticHeight)
         {}
 
+        CCoordinateGeodetic::CCoordinateGeodetic(double latitudeDegrees, double longitudeDegrees) :
+            CCoordinateGeodetic( { latitudeDegrees, BlackMisc::PhysicalQuantities::CAngleUnit::deg() }, { longitudeDegrees, BlackMisc::PhysicalQuantities::CAngleUnit::deg() }, { 0.0, BlackMisc::PhysicalQuantities::CLengthUnit::nullUnit() }) {}
+
+        CCoordinateGeodetic::CCoordinateGeodetic(double latitudeDegrees, double longitudeDegrees, double heightMeters) :
+            CCoordinateGeodetic( { latitudeDegrees, BlackMisc::PhysicalQuantities::CAngleUnit::deg() }, { longitudeDegrees, BlackMisc::PhysicalQuantities::CAngleUnit::deg() }, { heightMeters, BlackMisc::PhysicalQuantities::CLengthUnit::m() }) {}
+
         CLatitude CCoordinateGeodetic::latitude() const
         {
             return { std::atan2(m_z, std::hypot(m_x, m_y)), PhysicalQuantities::CAngleUnit::rad() };
diff --git a/src/blackmisc/geo/coordinategeodetic.h b/src/blackmisc/geo/coordinategeodetic.h
index dade2a58b..f14d39b8d 100644
--- a/src/blackmisc/geo/coordinategeodetic.h
+++ b/src/blackmisc/geo/coordinategeodetic.h
@@ -180,11 +180,13 @@ namespace BlackMisc
             CCoordinateGeodetic(const QVector3D &normal) : m_x(normal.x()), m_y(normal.y()), m_z(normal.z()) {}
 
             //! Constructor by values
-            CCoordinateGeodetic(CLatitude latitude, CLongitude longitude, BlackMisc::PhysicalQuantities::CLength height);
+            CCoordinateGeodetic(CLatitude latitude, CLongitude longitude, BlackMisc::PhysicalQuantities::CLength geodeticHeight);
+
+            //! Constructor by double values, but no geodetic height
+            CCoordinateGeodetic(double latitudeDegrees, double longitudeDegrees);
 
             //! Constructor by values
-            CCoordinateGeodetic(double latitudeDegrees, double longitudeDegrees, double heightMeters) :
-                CCoordinateGeodetic( { latitudeDegrees, BlackMisc::PhysicalQuantities::CAngleUnit::deg() }, { longitudeDegrees, BlackMisc::PhysicalQuantities::CAngleUnit::deg() }, { heightMeters, BlackMisc::PhysicalQuantities::CLengthUnit::m() }) {}
+            CCoordinateGeodetic(double latitudeDegrees, double longitudeDegrees, double heightMeters);
 
             //! \copydoc ICoordinateGeodetic::latitude
             virtual CLatitude latitude() const override;