diff --git a/src/FDM/JSBSim/models/FGPropagate.cpp b/src/FDM/JSBSim/models/FGPropagate.cpp
index 4bdebb247..2396fd332 100644
--- a/src/FDM/JSBSim/models/FGPropagate.cpp
+++ b/src/FDM/JSBSim/models/FGPropagate.cpp
@@ -792,8 +792,8 @@ void FGPropagate::bind(void)
   PropertyManager->Tie("velocities/eci-velocity-mag-fps", this, &FGPropagate::GetInertialVelocityMagnitude);
   PropertyManager->Tie("velocities/ned-velocity-mag-fps", this, &FGPropagate::GetNEDVelocityMagnitude);
 
-  PropertyManager->Tie("position/h-sl-ft", this, &FGPropagate::GetAltitudeASL, &FGPropagate::SetAltitudeASL, true);
-  PropertyManager->Tie("position/h-sl-meters", this, &FGPropagate::GetAltitudeASLmeters, &FGPropagate::SetAltitudeASLmeters, true);
+  PropertyManager->Tie("position/h-sl-ft", this, &FGPropagate::GetAltitudeASL, &FGPropagate::SetAltitudeASL, false);
+  PropertyManager->Tie("position/h-sl-meters", this, &FGPropagate::GetAltitudeASLmeters, &FGPropagate::SetAltitudeASLmeters, false);
   PropertyManager->Tie("position/lat-gc-rad", this, &FGPropagate::GetLatitude, &FGPropagate::SetLatitude, false);
   PropertyManager->Tie("position/long-gc-rad", this, &FGPropagate::GetLongitude, &FGPropagate::SetLongitude, false);
   PropertyManager->Tie("position/lat-gc-deg", this, &FGPropagate::GetLatitudeDeg, &FGPropagate::SetLatitudeDeg, false);
@@ -801,9 +801,9 @@ void FGPropagate::bind(void)
   PropertyManager->Tie("position/lat-geod-rad", this, &FGPropagate::GetGeodLatitudeRad);
   PropertyManager->Tie("position/lat-geod-deg", this, &FGPropagate::GetGeodLatitudeDeg);
   PropertyManager->Tie("position/geod-alt-ft", this, &FGPropagate::GetGeodeticAltitude);
-  PropertyManager->Tie("position/h-agl-ft", this,  &FGPropagate::GetDistanceAGL, &FGPropagate::SetDistanceAGL);
+  PropertyManager->Tie("position/h-agl-ft", this,  &FGPropagate::GetDistanceAGL, &FGPropagate::SetDistanceAGL, false);
   PropertyManager->Tie("position/geod-alt-km", this, &FGPropagate::GetGeodeticAltitudeKm);
-  PropertyManager->Tie("position/h-agl-km", this,  &FGPropagate::GetDistanceAGLKm, &FGPropagate::SetDistanceAGLKm);
+  PropertyManager->Tie("position/h-agl-km", this,  &FGPropagate::GetDistanceAGLKm, &FGPropagate::SetDistanceAGLKm, false);
   PropertyManager->Tie("position/radius-to-vehicle-ft", this, &FGPropagate::GetRadius);
   PropertyManager->Tie("position/terrain-elevation-asl-ft", this,
                           &FGPropagate::GetTerrainElevation,