diff --git a/src/blackmisc/simulation/interpolator.cpp b/src/blackmisc/simulation/interpolator.cpp
index 17735004c..708118d32 100644
--- a/src/blackmisc/simulation/interpolator.cpp
+++ b/src/blackmisc/simulation/interpolator.cpp
@@ -257,9 +257,12 @@ namespace BlackMisc::Simulation
             currentSituation.setGroundSpeed(pbh.getGroundSpeed());
 
             // use derived interpolant function
-            const bool interpolateGndFlag = pbh.getEndSituation().hasGroundDetailsForGndInterpolation() && pbh.getStartSituation().hasGroundDetailsForGndInterpolation();
-            currentSituation = interpolant.interpolatePositionAndAltitude(currentSituation);
+            const auto [interpolatedPosition, interpolatedAltitude] = interpolant.interpolatePositionAndAltitude();
+            currentSituation.setPosition(interpolatedPosition);
+            currentSituation.setAltitude(interpolatedAltitude);
+            currentSituation.setMSecsSinceEpoch(interpolant.getInterpolatedTime());
 
+            const bool interpolateGndFlag = pbh.getEndSituation().hasGroundDetailsForGndInterpolation() && pbh.getStartSituation().hasGroundDetailsForGndInterpolation();
             if (interpolateGndFlag)
             {
                 currentSituation.setOnGroundInfo(interpolant.interpolateGroundFactor());
diff --git a/src/blackmisc/simulation/interpolatorlinear.cpp b/src/blackmisc/simulation/interpolatorlinear.cpp
index 9730634d3..31fbd0c46 100644
--- a/src/blackmisc/simulation/interpolatorlinear.cpp
+++ b/src/blackmisc/simulation/interpolatorlinear.cpp
@@ -45,7 +45,7 @@ namespace BlackMisc::Simulation
     void CInterpolatorLinear::anchor()
     {}
 
-    CAircraftSituation CInterpolatorLinear::CInterpolant::interpolatePositionAndAltitude(const CAircraftSituation &situation) const
+    std::tuple<Geo::CCoordinateGeodetic, Aviation::CAltitude> CInterpolatorLinear::CInterpolant::interpolatePositionAndAltitude() const
     {
         const std::array<double, 3> startVec(m_startSituation.getPosition().normalVectorDouble());
         const std::array<double, 3> endVec(m_endSituation.getPosition().normalVectorDouble());
@@ -77,12 +77,7 @@ namespace BlackMisc::Simulation
         const CAltitude altitude((newAlt - oldAlt) * tf + oldAlt,
                                  oldAlt.getReferenceDatum());
 
-        CAircraftSituation interpolatedSituation(situation);
-        interpolatedSituation.setPosition(interpolatedPosition);
-        interpolatedSituation.setAltitude(altitude);
-        interpolatedSituation.setMSecsSinceEpoch(this->getInterpolatedTime());
-
-        return interpolatedSituation;
+        return { interpolatedPosition, altitude };
     }
 
     Aviation::COnGroundInfo CInterpolatorLinear::CInterpolant::interpolateGroundFactor() const
diff --git a/src/blackmisc/simulation/interpolatorlinear.h b/src/blackmisc/simulation/interpolatorlinear.h
index c39cf3cb2..ebc504f57 100644
--- a/src/blackmisc/simulation/interpolatorlinear.h
+++ b/src/blackmisc/simulation/interpolatorlinear.h
@@ -48,9 +48,8 @@ namespace BlackMisc
                 //! @}
 
                 //! Perform the interpolation
-                //! \param situation situation used as a base for interpolation. Contains for example the already interpolated PBH.
-                //! \return \p situation with interpolated position and altitude and updated timestamp
-                Aviation::CAircraftSituation interpolatePositionAndAltitude(const Aviation::CAircraftSituation &situation) const;
+                //! \return interpolated position and altitude
+                std::tuple<Geo::CCoordinateGeodetic, Aviation::CAltitude> interpolatePositionAndAltitude() const;
 
                 //! Interpolate the ground information/factor
                 Aviation::COnGroundInfo interpolateGroundFactor() const;
diff --git a/src/blackmisc/simulation/interpolatorspline.cpp b/src/blackmisc/simulation/interpolatorspline.cpp
index c7f2fca89..1c80deaa4 100644
--- a/src/blackmisc/simulation/interpolatorspline.cpp
+++ b/src/blackmisc/simulation/interpolatorspline.cpp
@@ -315,7 +315,7 @@ namespace BlackMisc::Simulation
         m_situationsAvailable = pa.size();
     }
 
-    CAircraftSituation CInterpolatorSpline::CInterpolant::interpolatePositionAndAltitude(const CAircraftSituation &currentSituation) const
+    std::tuple<Geo::CCoordinateGeodetic, Aviation::CAltitude> CInterpolatorSpline::CInterpolant::interpolatePositionAndAltitude() const
     {
         const double t1 = m_pa.t[1];
         const double t2 = m_pa.t[2]; // latest (adjusted)
@@ -327,7 +327,7 @@ namespace BlackMisc::Simulation
             BLACK_VERIFY_X(m_currentTimeMsSinceEpoc >= t1, Q_FUNC_INFO, "invalid timestamp t1");
             BLACK_VERIFY_X(m_currentTimeMsSinceEpoc < t2, Q_FUNC_INFO, "invalid timestamp t2"); // t1==t2 results in div/0
         }
-        if (!valid) { return CAircraftSituation::null(); }
+        if (!valid) { return { {}, {} }; }
 
         const double newX = evalSplineInterval(m_currentTimeMsSinceEpoc, t1, t2, m_pa.x[1], m_pa.x[2], m_pa.dx[1], m_pa.dx[2]);
         const double newY = evalSplineInterval(m_currentTimeMsSinceEpoc, t1, t2, m_pa.y[1], m_pa.y[2], m_pa.dy[1], m_pa.dy[2]);
@@ -340,9 +340,8 @@ namespace BlackMisc::Simulation
             BLACK_VERIFY_X(CAircraftSituation::isValidVector(m_pa.y), Q_FUNC_INFO, "invalid Y"); // all y values
             BLACK_VERIFY_X(CAircraftSituation::isValidVector(m_pa.z), Q_FUNC_INFO, "invalid Z"); // all z values
         }
-        if (!valid) { return CAircraftSituation::null(); }
+        if (!valid) { return { {}, {} }; }
 
-        CAircraftSituation newSituation(currentSituation);
         const std::array<double, 3> normalVector = { { newX, newY, newZ } };
         const CCoordinateGeodetic currentPosition(normalVector);
 
@@ -350,18 +349,14 @@ namespace BlackMisc::Simulation
         if (!valid && CBuildConfig::isLocalDeveloperDebugBuild())
         {
             BLACK_VERIFY_X(valid, Q_FUNC_INFO, "invalid vector");
-            CLogMessage(this).warning(u"Invalid vector for '%1' v: %2 %3 %4") << currentSituation.getCallsign().asString() << normalVector[0] << normalVector[1] << normalVector[2];
+            CLogMessage(this).warning(u"Invalid vector v: %2 %3 %4") << normalVector[0] << normalVector[1] << normalVector[2];
         }
-        if (!valid) { return CAircraftSituation::null(); }
+        if (!valid) { return { {}, {} }; }
 
         const double newA = evalSplineInterval(m_currentTimeMsSinceEpoc, t1, t2, m_pa.a[1], m_pa.a[2], m_pa.da[1], m_pa.da[2]);
         const CAltitude alt(newA, m_altitudeUnit);
 
-        newSituation.setPosition(currentPosition);
-        newSituation.setAltitude(alt);
-        newSituation.setMSecsSinceEpoch(this->getInterpolatedTime());
-
-        return newSituation;
+        return { currentPosition, alt };
     }
 
     Aviation::COnGroundInfo CInterpolatorSpline::CInterpolant::interpolateGroundFactor() const
diff --git a/src/blackmisc/simulation/interpolatorspline.h b/src/blackmisc/simulation/interpolatorspline.h
index 6721a1a63..c25690c8e 100644
--- a/src/blackmisc/simulation/interpolatorspline.h
+++ b/src/blackmisc/simulation/interpolatorspline.h
@@ -66,7 +66,7 @@ namespace BlackMisc::Simulation
             //! Perform the interpolation
             //! \param situation situation used as a base for interpolation. Contains for example the already interpolated PBH.
             //! \return \p situation with interpolated position and altitude and updated timestamp
-            Aviation::CAircraftSituation interpolatePositionAndAltitude(const Aviation::CAircraftSituation &currentSituation) const;
+            std::tuple<Geo::CCoordinateGeodetic, Aviation::CAltitude> interpolatePositionAndAltitude() const;
 
             //! Interpolate the ground information/factor
             Aviation::COnGroundInfo interpolateGroundFactor() const;