From ad51a9bde2995605984161af1b4273b28ce4fddc Mon Sep 17 00:00:00 2001
From: Erik Hofman <erik@ehofman.com>
Date: Sun, 28 Nov 2010 10:58:47 +0100
Subject: [PATCH] Sync JSBSim again

---
 src/FDM/JSBSim/FGFDMExec.cpp                  |  31 ++---
 src/FDM/JSBSim/FGFDMExec.h                    |  75 +++++++-----
 src/FDM/JSBSim/JSBSim.cxx                     |  15 ++-
 .../initialization/FGInitialCondition.cpp     |  89 +++++++-------
 .../initialization/FGInitialCondition.h       |   7 +-
 src/FDM/JSBSim/input_output/FGScript.cpp      |  12 +-
 src/FDM/JSBSim/math/FGModelFunctions.h        |  17 ++-
 src/FDM/JSBSim/models/FGAerodynamics.cpp      |  38 +++---
 src/FDM/JSBSim/models/FGAerodynamics.h        |  26 ++--
 src/FDM/JSBSim/models/FGAircraft.cpp          |  37 +++---
 src/FDM/JSBSim/models/FGAircraft.h            |  60 +++++-----
 src/FDM/JSBSim/models/FGAtmosphere.cpp        |  54 +++++----
 src/FDM/JSBSim/models/FGAtmosphere.h          |  14 +--
 src/FDM/JSBSim/models/FGAuxiliary.cpp         | 111 ++++++++++--------
 src/FDM/JSBSim/models/FGAuxiliary.h           |   7 +-
 src/FDM/JSBSim/models/FGBuoyantForces.cpp     |   4 +-
 src/FDM/JSBSim/models/FGExternalForce.h       |   4 +-
 src/FDM/JSBSim/models/FGExternalReactions.h   |   8 +-
 src/FDM/JSBSim/models/FGFCS.cpp               |  10 +-
 src/FDM/JSBSim/models/FGFCS.h                 |   4 +-
 src/FDM/JSBSim/models/FGGroundReactions.cpp   |   8 +-
 src/FDM/JSBSim/models/FGGroundReactions.h     |  12 +-
 src/FDM/JSBSim/models/FGInertial.cpp          |   6 +-
 src/FDM/JSBSim/models/FGInput.cpp             |   2 +-
 src/FDM/JSBSim/models/FGMassBalance.cpp       |  24 ++--
 src/FDM/JSBSim/models/FGMassBalance.h         |  10 +-
 src/FDM/JSBSim/models/FGModel.cpp             |  40 +------
 src/FDM/JSBSim/models/FGModel.h               |  26 +---
 src/FDM/JSBSim/models/FGOutput.cpp            |  32 ++++-
 src/FDM/JSBSim/models/FGOutput.h              |   5 +-
 src/FDM/JSBSim/models/FGPropagate.cpp         |  44 ++++---
 src/FDM/JSBSim/models/FGPropagate.h           |   5 +-
 src/FDM/JSBSim/models/FGPropulsion.cpp        |  45 ++++---
 src/FDM/JSBSim/models/FGPropulsion.h          |  36 +++---
 src/FDM/JSBSim/models/atmosphere/FGMSIS.cpp   |  20 ++--
 35 files changed, 477 insertions(+), 461 deletions(-)

diff --git a/src/FDM/JSBSim/FGFDMExec.cpp b/src/FDM/JSBSim/FGFDMExec.cpp
index 616dd6ea6..ab0bf8a9a 100644
--- a/src/FDM/JSBSim/FGFDMExec.cpp
+++ b/src/FDM/JSBSim/FGFDMExec.cpp
@@ -71,7 +71,7 @@ using namespace std;
 
 namespace JSBSim {
 
-static const char *IdSrc = "$Id: FGFDMExec.cpp,v 1.82 2010/10/07 03:17:29 jberndt Exp $";
+static const char *IdSrc = "$Id: FGFDMExec.cpp,v 1.83 2010/11/07 13:30:54 jberndt Exp $";
 static const char *IdHdr = ID_FDMEXEC;
 
 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@@ -95,23 +95,11 @@ void checkTied ( FGPropertyManager *node )
 }
 
 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-// Constructors
-FGFDMExec::FGFDMExec(FGPropertyManager* root) : Root(root), delete_root(false)
-{
-  FDMctr = new unsigned int;
-  *FDMctr = 0;
-  Initialize();
-  root_overload = (root != NULL);
-}
+// Constructor
 
-FGFDMExec::FGFDMExec(FGPropertyManager* root, unsigned int* fdmctr) : Root(root), delete_root(false), FDMctr(fdmctr)
+FGFDMExec::FGFDMExec(FGPropertyManager* root, unsigned int* fdmctr) : Root(root), FDMctr(fdmctr)
 {
-  Initialize();
-  root_overload = (root != NULL);
-}
 
-void FGFDMExec::Initialize()
-{
   Frame           = 0;
   Error           = 0;
   GroundCallback  = 0;
@@ -138,6 +126,7 @@ void FGFDMExec::Initialize()
   IsChild = false;
   holding = false;
   Terminate = false;
+  StandAlone = false;
 
   sim_time = 0.0;
   dT = 1.0/120.0; // a default timestep size. This is needed for when JSBSim is
@@ -152,8 +141,10 @@ void FGFDMExec::Initialize()
 
   if (Root == 0) {                 // Then this is the root FDM
     Root = new FGPropertyManager;  // Create the property manager
-    delete_root = true;
-    
+    StandAlone = true;
+  }
+
+  if (FDMctr == 0) {
     FDMctr = new unsigned int;     // Create and initialize the child FDM counter
     (*FDMctr) = 0;
   }
@@ -197,13 +188,13 @@ FGFDMExec::~FGFDMExec()
     checkTied( instance );
     DeAllocate();
     
-   if(FDMctr != 0 && !root_overload) {
+    if (IdFDM == 0) { // Meaning this is no child FDM
       if(Root != 0) {
-         if (delete_root)
+         if(StandAlone)
             delete Root;
          Root = 0;
       }
-      if (IdFDM == 0) { // Meaning this is no child FDM
+      if(FDMctr != 0) {
          delete FDMctr;
          FDMctr = 0;
       }
diff --git a/src/FDM/JSBSim/FGFDMExec.h b/src/FDM/JSBSim/FGFDMExec.h
index 38921ac7c..10736f4a4 100644
--- a/src/FDM/JSBSim/FGFDMExec.h
+++ b/src/FDM/JSBSim/FGFDMExec.h
@@ -41,7 +41,10 @@ SENTRY
 INCLUDES
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
 
-#include "models/FGModel.h"
+#include <vector>
+#include <string>
+
+//#include "models/FGModel.h"
 #include "models/FGOutput.h"
 #include "models/FGInput.h"
 #include "initialization/FGTrim.h"
@@ -53,14 +56,11 @@ INCLUDES
 #include "models/FGPropagate.h"
 #include "math/FGColumnVector3.h"
 
-#include <vector>
-#include <string>
-
 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 DEFINITIONS
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
 
-#define ID_FDMEXEC "$Id: FGFDMExec.h,v 1.54 2010/10/07 03:17:29 jberndt Exp $"
+#define ID_FDMEXEC "$Id: FGFDMExec.h,v 1.56 2010/11/18 20:37:10 jberndt Exp $"
 
 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 FORWARD DECLARATIONS
@@ -70,6 +70,20 @@ namespace JSBSim {
 
 class FGScript;
 class FGTrim;
+class FGAerodynamics;
+class FGAircraft;
+class FGAtmosphere;
+class FGAuxiliary;
+class FGBuoyantForces;
+class FGExternalReactions;
+class FGGroundReactions;
+class FGFCS;
+class FGInertial;
+class FGInput;
+class FGOutput;
+class FGPropagate;
+class FGPropulsion;
+class FGMassBalance;
 
 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 CLASS DOCUMENTATION
@@ -169,7 +183,7 @@ CLASS DOCUMENTATION
                                 property actually maps toa function call of DoTrim().
 
     @author Jon S. Berndt
-    @version $Revision: 1.54 $
+    @version $Revision: 1.56 $
 */
 
 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@@ -206,9 +220,8 @@ class FGFDMExec : public FGJSBBase, public FGXMLFileRead
 
 public:
 
-  /// Default constructors
-  FGFDMExec(FGPropertyManager* root = 0);
-  FGFDMExec(FGPropertyManager* root, unsigned int* fdmctr);
+  /// Default constructor
+  FGFDMExec(FGPropertyManager* root = 0, unsigned int* fdmctr = 0);
 
   /// Default destructor
   ~FGFDMExec();
@@ -292,49 +305,49 @@ public:
   /// @name Top-level executive State and Model retrieval mechanism
   //@{
   /// Returns the FGAtmosphere pointer.
-  inline FGAtmosphere* GetAtmosphere(void)    {return Atmosphere;}
+  FGAtmosphere* GetAtmosphere(void)    {return Atmosphere;}
   /// Returns the FGFCS pointer.
-  inline FGFCS* GetFCS(void)                  {return FCS;}
+  FGFCS* GetFCS(void)                  {return FCS;}
   /// Returns the FGPropulsion pointer.
-  inline FGPropulsion* GetPropulsion(void)    {return Propulsion;}
+  FGPropulsion* GetPropulsion(void)    {return Propulsion;}
   /// Returns the FGAircraft pointer.
-  inline FGMassBalance* GetMassBalance(void)  {return MassBalance;}
+  FGMassBalance* GetMassBalance(void)  {return MassBalance;}
   /// Returns the FGAerodynamics pointer
-  inline FGAerodynamics* GetAerodynamics(void){return Aerodynamics;}
+  FGAerodynamics* GetAerodynamics(void){return Aerodynamics;}
   /// Returns the FGInertial pointer.
-  inline FGInertial* GetInertial(void)        {return Inertial;}
+  FGInertial* GetInertial(void)        {return Inertial;}
   /// Returns the FGGroundReactions pointer.
-  inline FGGroundReactions* GetGroundReactions(void) {return GroundReactions;}
+  FGGroundReactions* GetGroundReactions(void) {return GroundReactions;}
   /// Returns the FGExternalReactions pointer.
-  inline FGExternalReactions* GetExternalReactions(void) {return ExternalReactions;}
+  FGExternalReactions* GetExternalReactions(void) {return ExternalReactions;}
   /// Returns the FGBuoyantForces pointer.
-  inline FGBuoyantForces* GetBuoyantForces(void) {return BuoyantForces;}
+  FGBuoyantForces* GetBuoyantForces(void) {return BuoyantForces;}
   /// Returns the FGAircraft pointer.
-  inline FGAircraft* GetAircraft(void)        {return Aircraft;}
+  FGAircraft* GetAircraft(void)        {return Aircraft;}
   /// Returns the FGPropagate pointer.
-  inline FGPropagate* GetPropagate(void)      {return Propagate;}
+  FGPropagate* GetPropagate(void)      {return Propagate;}
   /// Returns the FGAuxiliary pointer.
-  inline FGAuxiliary* GetAuxiliary(void)      {return Auxiliary;}
+  FGAuxiliary* GetAuxiliary(void)      {return Auxiliary;}
   /// Returns the FGInput pointer.
-  inline FGInput* GetInput(void)              {return Input;}
+  FGInput* GetInput(void)              {return Input;}
   /// Returns the FGGroundCallback pointer.
-  inline FGGroundCallback* GetGroundCallback(void) {return GroundCallback;}
+  FGGroundCallback* GetGroundCallback(void) {return GroundCallback;}
   /// Retrieves the script object
-  inline FGScript* GetScript(void) {return Script;}
+  FGScript* GetScript(void) {return Script;}
   // Returns a pointer to the FGInitialCondition object
-  inline FGInitialCondition* GetIC(void)      {return IC;}
+  FGInitialCondition* GetIC(void)      {return IC;}
   // Returns a pointer to the FGTrim object
   FGTrim* GetTrim(void);
   //@}
 
   /// Retrieves the engine path.
-  inline const string& GetEnginePath(void)    {return EnginePath;}
+  const string& GetEnginePath(void)    {return EnginePath;}
   /// Retrieves the aircraft path.
-  inline const string& GetAircraftPath(void)  {return AircraftPath;}
+  const string& GetAircraftPath(void)  {return AircraftPath;}
   /// Retrieves the systems path.
-  inline const string& GetSystemsPath(void)   {return SystemsPath;}
+  const string& GetSystemsPath(void)   {return SystemsPath;}
   /// Retrieves the full aircraft path name.
-  inline const string& GetFullAircraftPath(void) {return FullAircraftPath;}
+  const string& GetFullAircraftPath(void) {return FullAircraftPath;}
 
   /** Retrieves the value of a property.
       @param property the name of the property
@@ -524,7 +537,6 @@ private:
   bool Constructing;
   bool modelLoaded;
   bool IsChild;
-  bool root_overload;
   string modelName;
   string AircraftPath;
   string FullAircraftPath;
@@ -556,7 +568,7 @@ private:
   FGTrim*             Trim;
 
   FGPropertyManager* Root;
-  bool delete_root;
+  bool StandAlone;
   FGPropertyManager* instance;
   
   // The FDM counter is used to give each child FDM an unique ID. The root FDM has the ID 0
@@ -567,7 +579,6 @@ private:
   vector <childData*> ChildFDMList;
   vector <FGModel*> Models;
 
-  void Initialize();
   bool ReadFileHeader(Element*);
   bool ReadChild(Element*);
   bool ReadPrologue(Element*);
diff --git a/src/FDM/JSBSim/JSBSim.cxx b/src/FDM/JSBSim/JSBSim.cxx
index 612424629..e8a96c018 100644
--- a/src/FDM/JSBSim/JSBSim.cxx
+++ b/src/FDM/JSBSim/JSBSim.cxx
@@ -18,7 +18,7 @@
 // along with this program; if not, write to the Free Software
 // Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 //
-// $Id: JSBSim.cxx,v 1.63 2010/10/07 03:45:40 jberndt Exp $
+// $Id: JSBSim.cxx,v 1.64 2010/10/31 04:49:25 jberndt Exp $
 
 
 #ifdef HAVE_CONFIG_H
@@ -452,7 +452,7 @@ void FGJSBsim::update( double dt )
     // ground in this area.
     double groundCacheRadius = acrad + 2*dt*Propagate->GetUVW().Magnitude();
     double alt, slr, lat, lon;
-    FGColumnVector3 cart = Auxiliary->GetLocationVRP();
+    FGLocation cart = Auxiliary->GetLocationVRP();
     if ( needTrim && startup_trim->getBoolValue() ) {
       alt = fgic->GetAltitudeASLFtIC();
       slr = fgic->GetSeaLevelRadiusFtIC();
@@ -488,9 +488,9 @@ void FGJSBsim::update( double dt )
 
     if ( needTrim ) {
       if ( startup_trim->getBoolValue() ) {
-        double contact[3], d[3], agl;
+        double contact[3], d[3], vel[3], agl;
         get_agl_ft(fdmex->GetSimTime(), cart_pos, SG_METER_TO_FEET*2, contact,
-                   d, d, d, &agl);
+                   d, vel, d, &agl);
         double terrain_alt = sqrt(contact[0]*contact[0] + contact[1]*contact[1]
              + contact[2]*contact[2]) - fgic->GetSeaLevelRadiusFtIC();
 
@@ -498,6 +498,13 @@ void FGJSBsim::update( double dt )
           "Ready to trim, terrain elevation is: "
             << terrain_alt * SG_METER_TO_FEET );
 
+        if (fgGetBool("/sim/presets/onground")) {
+          FGColumnVector3 gndVelNED = cart.GetTec2l()
+                                    * FGColumnVector3(vel[0], vel[1], vel[2]);
+          fgic->SetVNorthFpsIC(gndVelNED(1));
+          fgic->SetVEastFpsIC(gndVelNED(2));
+          fgic->SetVDownFpsIC(gndVelNED(3));
+        }
         fgic->SetTerrainElevationFtIC( terrain_alt );
         do_trim();
       } else {
diff --git a/src/FDM/JSBSim/initialization/FGInitialCondition.cpp b/src/FDM/JSBSim/initialization/FGInitialCondition.cpp
index d8452c77b..cb1fe5710 100644
--- a/src/FDM/JSBSim/initialization/FGInitialCondition.cpp
+++ b/src/FDM/JSBSim/initialization/FGInitialCondition.cpp
@@ -62,7 +62,7 @@ using namespace std;
 
 namespace JSBSim {
 
-static const char *IdSrc = "$Id: FGInitialCondition.cpp,v 1.46 2010/09/29 02:19:05 jberndt Exp $";
+static const char *IdSrc = "$Id: FGInitialCondition.cpp,v 1.50 2010/11/20 16:38:43 bcoconni Exp $";
 static const char *IdHdr = ID_INITIALCONDITION;
 
 //******************************************************************************
@@ -187,7 +187,7 @@ void FGInitialCondition::WriteStateFile(int num)
     outfile << "  <psi unit=\"DEG\"> " << Propagate->GetEuler(ePsi) << " </psi>" << endl;
     outfile << "  <longitude unit=\"DEG\"> " << Propagate->GetLongitudeDeg() << " </longitude>" << endl;
     outfile << "  <latitude unit=\"DEG\"> " << Propagate->GetLatitudeDeg() << " </latitude>" << endl;
-    outfile << "  <altitude unit=\"FT\"> " << Propagate->GetAltitudeASL() << " </altitude>" << endl;
+    outfile << "  <altitude unit=\"FT\"> " << Propagate->GetDistanceAGL() << " </altitude>" << endl;
     outfile << "</initialize>" << endl;
     outfile.close();
   } else {
@@ -225,20 +225,37 @@ void FGInitialCondition::SetVequivalentKtsIC(double tt) {
 
 //******************************************************************************
 
-void FGInitialCondition::SetVgroundFpsIC(double tt) {
-  double ua,va,wa;
-  double vxz;
+void FGInitialCondition::calcAeroEuler(void)
+{
+  double ua = u + uw;
+  double va = v + vw;
+  double wa = w + ww;
+  vt = sqrt( ua*ua + va*va + wa*wa );
+  alpha = beta = 0.0;
+  calpha = cbeta = 1.0;
+  salpha = sbeta = 0.0;
+  double vxz = sqrt( u*u + w*w );
+  if( w != 0 ) alpha = atan2( w, u );
+  if( vxz != 0 ) {
+    beta = atan2( v, vxz );
+    calpha = u / vxz;
+    salpha = w / vxz;
+  }
+  double vn = sqrt(vxz*vxz + v*v);
+  if (vn != 0) {
+    cbeta = vxz / vn;
+    sbeta = v / vn;
+  }
+}
 
+//******************************************************************************
+
+void FGInitialCondition::SetVgroundFpsIC(double tt) {
   vg=tt;
   lastSpeedSet=setvg;
   vnorth = vg*cos(psi); veast = vg*sin(psi); vdown = 0;
   calcUVWfromNED();
-  ua = u + uw; va = v + vw; wa = w + ww;
-  vt = sqrt( ua*ua + va*va + wa*wa );
-  alpha = beta = 0;
-  vxz = sqrt( u*u + w*w );
-  if( w != 0 ) alpha = atan2( w, u );
-  if( vxz != 0 ) beta = atan2( v, vxz );
+  calcAeroEuler();
   mach=vt/fdmex->GetAtmosphere()->GetSoundSpeed();
   vc=calcVcas(mach);
   ve=vt*sqrt(fdmex->GetAtmosphere()->GetDensityRatio());
@@ -336,7 +353,7 @@ void FGInitialCondition::SetPsiRadIC(double tt) {
 
 void FGInitialCondition::SetUBodyFpsIC(double tt) {
   u=tt;
-  vt=sqrt(u*u + v*v + w*w);
+  calcAeroEuler();
   lastSpeedSet=setuvw;
 }
 
@@ -344,7 +361,7 @@ void FGInitialCondition::SetUBodyFpsIC(double tt) {
 
 void FGInitialCondition::SetVBodyFpsIC(double tt) {
   v=tt;
-  vt=sqrt(u*u + v*v + w*w);
+  calcAeroEuler();
   lastSpeedSet=setuvw;
 }
 
@@ -352,7 +369,7 @@ void FGInitialCondition::SetVBodyFpsIC(double tt) {
 
 void FGInitialCondition::SetWBodyFpsIC(double tt) {
   w=tt;
-  vt=sqrt( u*u + v*v + w*w );
+  calcAeroEuler();
   lastSpeedSet=setuvw;
 }
 
@@ -360,16 +377,9 @@ void FGInitialCondition::SetWBodyFpsIC(double tt) {
 //******************************************************************************
 
 void FGInitialCondition::SetVNorthFpsIC(double tt) {
-  double ua,va,wa;
-  double vxz;
   vnorth = tt;
   calcUVWfromNED();
-  ua = u + uw; va = v + vw; wa = w + ww;
-  vt = sqrt( ua*ua + va*va + wa*wa );
-  alpha = beta = 0;
-  vxz = sqrt( u*u + w*w );
-  if( w != 0 ) alpha = atan2( w, u );
-  if( vxz != 0 ) beta = atan2( v, vxz );
+  calcAeroEuler();
   mach=vt/fdmex->GetAtmosphere()->GetSoundSpeed();
   vc=calcVcas(mach);
   ve=vt*sqrt(fdmex->GetAtmosphere()->GetDensityRatio());
@@ -379,16 +389,9 @@ void FGInitialCondition::SetVNorthFpsIC(double tt) {
 //******************************************************************************
 
 void FGInitialCondition::SetVEastFpsIC(double tt) {
-  double ua,va,wa;
-  double vxz;
   veast = tt;
   calcUVWfromNED();
-  ua = u + uw; va = v + vw; wa = w + ww;
-  vt = sqrt( ua*ua + va*va + wa*wa );
-  alpha = beta = 0;
-  vxz = sqrt( u*u + w*w );
-  if( w != 0 ) alpha = atan2( w, u );
-  if( vxz != 0 ) beta = atan2( v, vxz );
+  calcAeroEuler();
   mach=vt/fdmex->GetAtmosphere()->GetSoundSpeed();
   vc=calcVcas(mach);
   ve=vt*sqrt(fdmex->GetAtmosphere()->GetDensityRatio());
@@ -398,16 +401,9 @@ void FGInitialCondition::SetVEastFpsIC(double tt) {
 //******************************************************************************
 
 void FGInitialCondition::SetVDownFpsIC(double tt) {
-  double ua,va,wa;
-  double vxz;
   vdown = tt;
   calcUVWfromNED();
-  ua = u + uw; va = v + vw; wa = w + ww;
-  vt = sqrt( ua*ua + va*va + wa*wa );
-  alpha = beta = 0;
-  vxz = sqrt( u*u + w*w );
-  if( w != 0 ) alpha = atan2( w, u );
-  if( vxz != 0 ) beta = atan2( v, vxz );
+  calcAeroEuler();
   mach=vt/fdmex->GetAtmosphere()->GetSoundSpeed();
   vc=calcVcas(mach);
   ve=vt*sqrt(fdmex->GetAtmosphere()->GetDensityRatio());
@@ -885,6 +881,7 @@ bool FGInitialCondition::Load(string rstfile, bool useStoredPath)
 
 bool FGInitialCondition::Load_v1(void)
 {
+  bool result = true;
   int n;
 
   if (document->FindElement("latitude"))
@@ -953,13 +950,18 @@ bool FGInitialCondition::Load_v1(void)
   Element* running_elements = document->FindElement("running");
   while (running_elements) {
     n = int(running_elements->GetDataAsNumber());
-    propulsion->InitRunning(n);
+    try {
+      propulsion->InitRunning(n);
+    } catch (string str) {
+      cerr << str << endl;
+      result = false;
+    }
     running_elements = document->FindNextElement("running");
   }
 
   fdmex->RunIC();
 
-  return true;
+  return result;
 }
 
 //******************************************************************************
@@ -1213,7 +1215,12 @@ bool FGInitialCondition::Load_v2(void)
   Element* running_elements = document->FindElement("running");
   while (running_elements) {
     n = int(running_elements->GetDataAsNumber());
-    propulsion->InitRunning(n);
+    try {
+      propulsion->InitRunning(n);
+    } catch (string str) {
+      cerr << str << endl;
+      result = false;
+    }
     running_elements = document->FindNextElement("running");
   }
 
diff --git a/src/FDM/JSBSim/initialization/FGInitialCondition.h b/src/FDM/JSBSim/initialization/FGInitialCondition.h
index b5c8c2819..ebd65bda9 100644
--- a/src/FDM/JSBSim/initialization/FGInitialCondition.h
+++ b/src/FDM/JSBSim/initialization/FGInitialCondition.h
@@ -56,7 +56,7 @@ INCLUDES
 DEFINITIONS
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
 
-#define ID_INITIALCONDITION "$Id: FGInitialCondition.h,v 1.20 2010/02/15 03:22:57 jberndt Exp $"
+#define ID_INITIALCONDITION "$Id: FGInitialCondition.h,v 1.22 2010/11/20 16:38:43 bcoconni Exp $"
 
 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 FORWARD DECLARATIONS
@@ -151,7 +151,7 @@ CLASS DOCUMENTATION
    - vc (calibrated airspeed, ft/sec)
    - mach (mach)
    - vground (ground speed, ft/sec)
-   - running (0 or 1)
+   - running (-1 for all engines, 0 for no engines, 1 ... n for specific engines)
 
    <h3>Properties</h3>
    @property ic/vc-kts (read/write) Calibrated airspeed initial condition in knots
@@ -202,7 +202,7 @@ CLASS DOCUMENTATION
    @property ic/r-rad_sec (read/write) Yaw rate initial condition in radians/second
 
    @author Tony Peden
-   @version "$Id: FGInitialCondition.h,v 1.20 2010/02/15 03:22:57 jberndt Exp $"
+   @version "$Id: FGInitialCondition.h,v 1.22 2010/11/20 16:38:43 bcoconni Exp $"
 */
 
 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@@ -661,6 +661,7 @@ private:
   double calcVcas(double Mach);
   void calcUVWfromNED(void);
   void calcWindUVW(void);
+  void calcAeroEuler(void);
 
   bool findInterval(double x,double guess);
   bool solve(double *y, double x);
diff --git a/src/FDM/JSBSim/input_output/FGScript.cpp b/src/FDM/JSBSim/input_output/FGScript.cpp
index bd940bb4c..1697e7ce7 100755
--- a/src/FDM/JSBSim/input_output/FGScript.cpp
+++ b/src/FDM/JSBSim/input_output/FGScript.cpp
@@ -54,7 +54,7 @@ using namespace std;
 
 namespace JSBSim {
 
-static const char *IdSrc = "$Id: FGScript.cpp,v 1.41 2010/07/08 11:36:28 jberndt Exp $";
+static const char *IdSrc = "$Id: FGScript.cpp,v 1.42 2010/11/24 12:58:39 jberndt Exp $";
 static const char *IdHdr = ID_FGSCRIPT;
 
 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@@ -376,7 +376,9 @@ bool FGScript::RunScript(void)
       Events[ev_ctr].Triggered = true;
 
     } else if (Events[ev_ctr].Persistent) { // If the event is persistent, reset the trigger.
-
+      Events[ev_ctr].Triggered = false; // Reset the trigger for persistent events
+      Events[ev_ctr].Notified = false;  // Also reset the notification flag
+    } else if (Events[ev_ctr].Continuous) { // If the event is continuous, reset the trigger.
       Events[ev_ctr].Triggered = false; // Reset the trigger for persistent events
       Events[ev_ctr].Notified = false;  // Also reset the notification flag
     }
@@ -486,9 +488,11 @@ void FGScript::Debug(int from)
         cout << ":" << endl;
 
         if (Events[i].Persistent)
-          cout << "  " << "Always executes";
+          cout << "  " << "Whenever triggered, executes once";
+        else if (Events[i].Continuous)
+          cout << "  " << "While true, always executes";
         else
-          cout << "  " << "Executes once";
+          cout << "  " << "When first triggered, executes once";
 
         Events[i].Condition->PrintCondition();
 
diff --git a/src/FDM/JSBSim/math/FGModelFunctions.h b/src/FDM/JSBSim/math/FGModelFunctions.h
index f98f2b4bf..2b3f94e17 100755
--- a/src/FDM/JSBSim/math/FGModelFunctions.h
+++ b/src/FDM/JSBSim/math/FGModelFunctions.h
@@ -44,7 +44,7 @@ INCLUDES
 DEFINITIONS
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
 
-#define ID_MODELFUNCTIONS "$Id: FGModelFunctions.h,v 1.2 2010/08/24 10:30:14 jberndt Exp $"
+#define ID_MODELFUNCTIONS "$Id: FGModelFunctions.h,v 1.3 2010/11/17 03:18:37 jberndt Exp $"
 
 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 FORWARD DECLARATIONS
@@ -56,15 +56,24 @@ namespace JSBSim {
 CLASS DOCUMENTATION
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
 
-/** 
-@author Jon Berndt
+/** The model functions class provides the capability for loading, storing, and
+    executing arbitrary functions.
+    For certain classes, such as the engine, aerodynamics, ground reactions, 
+    mass balance, etc., it can be useful to incorporate special functions that
+    can operate on the local model parameters before and/or after the model
+    executes. For example, there is no inherent chamber pressure calculation
+    done in the rocket engine model. However, an arbitrary function can be added
+    to a specific rocket engine XML configuration file. It would be tagged with
+    a "pre" or "post" type attribute to denote whether the function is to be
+    executed before or after the standard model algorithm.
+    @author Jon Berndt
 */
 
 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 DECLARATION: FGModelFunctions
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
 
-  class FGModelFunctions : public FGJSBBase
+class FGModelFunctions : public FGJSBBase
 {
 public:
   ~FGModelFunctions();
diff --git a/src/FDM/JSBSim/models/FGAerodynamics.cpp b/src/FDM/JSBSim/models/FGAerodynamics.cpp
index 0a384447d..07e639860 100644
--- a/src/FDM/JSBSim/models/FGAerodynamics.cpp
+++ b/src/FDM/JSBSim/models/FGAerodynamics.cpp
@@ -52,7 +52,7 @@ using namespace std;
 
 namespace JSBSim {
 
-static const char *IdSrc = "$Id: FGAerodynamics.cpp,v 1.34 2010/10/15 11:32:41 jberndt Exp $";
+static const char *IdSrc = "$Id: FGAerodynamics.cpp,v 1.35 2010/11/18 12:38:06 jberndt Exp $";
 static const char *IdHdr = ID_AERODYNAMICS;
 
 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@@ -134,24 +134,28 @@ bool FGAerodynamics::InitModel(void)
 
 bool FGAerodynamics::Run(void)
 {
-  unsigned int axis_ctr, ctr;
-  double alpha, twovel;
 
   if (FGModel::Run()) return true;
   if (FDMExec->Holding()) return false; // if paused don't execute
 
+  unsigned int axis_ctr, ctr;
+  const double alpha=FDMExec->GetAuxiliary()->Getalpha();
+  const double twovel=2*FDMExec->GetAuxiliary()->GetVt();
+  const double qbar = FDMExec->GetAuxiliary()->Getqbar();
+  const double wingarea = FDMExec->GetAircraft()->GetWingArea();
+  const double wingspan = FDMExec->GetAircraft()->GetWingSpan();
+  const double wingchord = FDMExec->GetAircraft()->Getcbar();
+  const double wingincidence = FDMExec->GetAircraft()->GetWingIncidence();
   RunPreFunctions();
 
   // calculate some oft-used quantities for speed
 
-  twovel = 2*Auxiliary->GetVt();
   if (twovel != 0) {
-    bi2vel = Aircraft->GetWingSpan() / twovel;
-    ci2vel = Aircraft->Getcbar() / twovel;
+    bi2vel = wingspan / twovel;
+    ci2vel = wingchord / twovel;
   }
-  alphaw = Auxiliary->Getalpha() + Aircraft->GetWingIncidence();
-  alpha = Auxiliary->Getalpha();
-  qbar_area = Aircraft->GetWingArea() * Auxiliary->Getqbar();
+  alphaw = alpha + wingincidence;
+  qbar_area = wingarea * qbar;
 
   if (alphaclmax != 0) {
     if (alpha > 0.85*alphaclmax) {
@@ -204,18 +208,18 @@ bool FGAerodynamics::Run(void)
   }
 
   // Calculate aerodynamic reference point shift, if any
-  if (AeroRPShift) vDeltaRP(eX) = AeroRPShift->GetValue()*Aircraft->Getcbar()*12.0;
+  if (AeroRPShift) vDeltaRP(eX) = AeroRPShift->GetValue()*wingchord*12.0;
 
   // Calculate lift coefficient squared
-  if ( Auxiliary->Getqbar() > 0) {
-    clsq = vFw(eLift) / (Aircraft->GetWingArea()*Auxiliary->Getqbar());
+  if ( qbar > 0) {
+    clsq = vFw(eLift) / (wingarea*qbar);
     clsq *= clsq;
   }
 
   // Calculate lift Lift over Drag
   if ( fabs(vFw(eDrag)) > 0.0) lod = fabs( vFw(eLift) / vFw(eDrag) );
 
-  vDXYZcg = MassBalance->StructuralToBody(Aircraft->GetXYZrp() + vDeltaRP);
+  vDXYZcg = FDMExec->GetMassBalance()->StructuralToBody(FDMExec->GetAircraft()->GetXYZrp() + vDeltaRP);
 
   vMoments = vDXYZcg*vForces; // M = r X F
 
@@ -250,8 +254,8 @@ FGMatrix33& FGAerodynamics::GetTw2b(void)
 {
   double ca, cb, sa, sb;
 
-  double alpha = Auxiliary->Getalpha();
-  double beta  = Auxiliary->Getbeta();
+  double alpha = FDMExec->GetAuxiliary()->Getalpha();
+  double beta  = FDMExec->GetAuxiliary()->Getbeta();
 
   ca = cos(alpha);
   sa = sin(alpha);
@@ -278,8 +282,8 @@ FGMatrix33& FGAerodynamics::GetTb2w(void)
   double alpha,beta;
   double ca, cb, sa, sb;
 
-  alpha = Auxiliary->Getalpha();
-  beta  = Auxiliary->Getbeta();
+  alpha = FDMExec->GetAuxiliary()->Getalpha();
+  beta  = FDMExec->GetAuxiliary()->Getbeta();
 
   ca = cos(alpha);
   sa = sin(alpha);
diff --git a/src/FDM/JSBSim/models/FGAerodynamics.h b/src/FDM/JSBSim/models/FGAerodynamics.h
index 0f966d845..a5e278195 100644
--- a/src/FDM/JSBSim/models/FGAerodynamics.h
+++ b/src/FDM/JSBSim/models/FGAerodynamics.h
@@ -52,7 +52,7 @@ INCLUDES
 DEFINITIONS
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
 
-#define ID_AERODYNAMICS "$Id: FGAerodynamics.h,v 1.20 2009/11/12 13:08:11 jberndt Exp $"
+#define ID_AERODYNAMICS "$Id: FGAerodynamics.h,v 1.21 2010/11/18 12:38:06 jberndt Exp $"
 
 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 FORWARD DECLARATIONS
@@ -109,7 +109,7 @@ CLASS DOCUMENTATION
     Systems may NOT be combined, or a load error will occur.
 
     @author Jon S. Berndt, Tony Peden
-    @version $Revision: 1.20 $
+    @version $Revision: 1.21 $
 */
 
 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@@ -141,7 +141,7 @@ public:
 
   /** Gets the total aerodynamic force vector.
       @return a force vector reference. */
-  FGColumnVector3& GetForces(void) {return vForces;}
+  const FGColumnVector3& GetForces(void) const {return vForces;}
 
   /** Gets the aerodynamic force for an axis.
       @param n Axis index. This could be 0, 1, or 2, or one of the
@@ -151,7 +151,7 @@ public:
 
   /** Gets the total aerodynamic moment vector.
       @return a moment vector reference. */
-  FGColumnVector3& GetMoments(void) {return vMoments;}
+  const FGColumnVector3& GetMoments(void) const {return vMoments;}
 
   /** Gets the aerodynamic moment for an axis.
       @return the moment about a single axis (as described also in the
@@ -160,7 +160,7 @@ public:
 
   /** Retrieves the aerodynamic forces in the wind axes.
       @return a reference to a column vector containing the wind axis forces. */
-  FGColumnVector3& GetvFw(void) { return vFw; }
+  const FGColumnVector3& GetvFw(void) const { return vFw; }
 
   /** Retrieves the aerodynamic forces in the wind axes, given an axis.
       @param axis the axis to return the force for (eX, eY, eZ).
@@ -169,22 +169,22 @@ public:
   double GetvFw(int axis) const { return vFw(axis); }
 
   /** Retrieves the lift over drag ratio */
-  inline double GetLoD(void) const { return lod; }
+  double GetLoD(void) const { return lod; }
 
   /** Retrieves the square of the lift coefficient. */
-  inline double GetClSquared(void) const { return clsq; }
-  inline double GetAlphaCLMax(void) const { return alphaclmax; }
-  inline double GetAlphaCLMin(void) const { return alphaclmin; }
+  double GetClSquared(void) const { return clsq; }
+  double GetAlphaCLMax(void) const { return alphaclmax; }
+  double GetAlphaCLMin(void) const { return alphaclmin; }
 
-  inline double GetHysteresisParm(void) const { return stall_hyst; }
-  inline double GetStallWarn(void) const { return impending_stall; }
+  double GetHysteresisParm(void) const { return stall_hyst; }
+  double GetStallWarn(void) const { return impending_stall; }
   double GetAlphaW(void) const { return alphaw; }
 
   double GetBI2Vel(void) const { return bi2vel; }
   double GetCI2Vel(void) const { return ci2vel; }
 
-  inline void SetAlphaCLMax(double tt) { alphaclmax=tt; }
-  inline void SetAlphaCLMin(double tt) { alphaclmin=tt; }
+  void SetAlphaCLMax(double tt) { alphaclmax=tt; }
+  void SetAlphaCLMin(double tt) { alphaclmin=tt; }
 
   /** Gets the strings for the current set of coefficients.
       @param delimeter either a tab or comma string depending on output type
diff --git a/src/FDM/JSBSim/models/FGAircraft.cpp b/src/FDM/JSBSim/models/FGAircraft.cpp
index 0ed6ac74f..079748274 100644
--- a/src/FDM/JSBSim/models/FGAircraft.cpp
+++ b/src/FDM/JSBSim/models/FGAircraft.cpp
@@ -40,7 +40,7 @@ INCLUDES
 
 #include <sys/stat.h>
 #include <sys/types.h>
-
+#include <iostream>
 #include <cmath>
 
 #include "FGAircraft.h"
@@ -54,7 +54,6 @@ INCLUDES
 #include "FGPropagate.h"
 #include "FGPropulsion.h"
 #include "input_output/FGPropertyManager.h"
-#include <iostream>
 
 using namespace std;
 
@@ -68,7 +67,7 @@ DEFINITIONS
 GLOBAL DATA
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
 
-static const char *IdSrc = "$Id: FGAircraft.cpp,v 1.28 2010/09/07 00:40:03 jberndt Exp $";
+static const char *IdSrc = "$Id: FGAircraft.cpp,v 1.29 2010/11/18 12:38:06 jberndt Exp $";
 static const char *IdHdr = ID_AIRCRAFT;
 
 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@@ -118,30 +117,30 @@ bool FGAircraft::Run(void)
 
   vForces.InitMatrix();
   if (!HoldDown) {
-    vForces += Aerodynamics->GetForces();
-    vForces += Propulsion->GetForces();
-    vForces += GroundReactions->GetForces();
-    vForces += ExternalReactions->GetForces();
-    vForces += BuoyantForces->GetForces();
+    vForces += FDMExec->GetAerodynamics()->GetForces();
+    vForces += FDMExec->GetPropulsion()->GetForces();
+    vForces += FDMExec->GetGroundReactions()->GetForces();
+    vForces += FDMExec->GetExternalReactions()->GetForces();
+    vForces += FDMExec->GetBuoyantForces()->GetForces();
   } else {
-    const FGMatrix33& mTl2b = Propagate->GetTl2b();
-    vForces = mTl2b * FGColumnVector3(0,0,-MassBalance->GetWeight());
+    const FGMatrix33& mTl2b = FDMExec->GetPropagate()->GetTl2b();
+    vForces = mTl2b * FGColumnVector3(0,0,-FDMExec->GetMassBalance()->GetWeight());
   }
 
   vMoments.InitMatrix();
   if (!HoldDown) {
-    vMoments += Aerodynamics->GetMoments();
-    vMoments += Propulsion->GetMoments();
-    vMoments += GroundReactions->GetMoments();
-    vMoments += ExternalReactions->GetMoments();
-    vMoments += BuoyantForces->GetMoments();
+    vMoments += FDMExec->GetAerodynamics()->GetMoments();
+    vMoments += FDMExec->GetPropulsion()->GetMoments();
+    vMoments += FDMExec->GetGroundReactions()->GetMoments();
+    vMoments += FDMExec->GetExternalReactions()->GetMoments();
+    vMoments += FDMExec->GetBuoyantForces()->GetMoments();
   }
 
-  vBodyAccel = vForces/MassBalance->GetMass();
+  vBodyAccel = vForces/FDMExec->GetMassBalance()->GetMass();
 
-  vNcg = vBodyAccel/Inertial->SLgravity();
+  vNcg = vBodyAccel/FDMExec->GetInertial()->SLgravity();
 
-  vNwcg = Aerodynamics->GetTb2w() * vNcg;
+  vNwcg = FDMExec->GetAerodynamics()->GetTb2w() * vNcg;
   vNwcg(3) = 1.0 - vNwcg(3);
 
   RunPostFunctions();
@@ -153,7 +152,7 @@ bool FGAircraft::Run(void)
 
 double FGAircraft::GetNlf(void) const
 {
-  return -1*Aerodynamics->GetvFw(3)/MassBalance->GetWeight();
+  return (-FDMExec->GetAerodynamics()->GetvFw(3))/FDMExec->GetMassBalance()->GetWeight();
 }
 
 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
diff --git a/src/FDM/JSBSim/models/FGAircraft.h b/src/FDM/JSBSim/models/FGAircraft.h
index a03656895..c3060db37 100644
--- a/src/FDM/JSBSim/models/FGAircraft.h
+++ b/src/FDM/JSBSim/models/FGAircraft.h
@@ -49,7 +49,7 @@ INCLUDES
 DEFINITIONS
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
 
-#define ID_AIRCRAFT "$Id: FGAircraft.h,v 1.15 2009/10/24 22:59:30 jberndt Exp $"
+#define ID_AIRCRAFT "$Id: FGAircraft.h,v 1.16 2010/11/18 12:38:06 jberndt Exp $"
 
 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 FORWARD DECLARATIONS
@@ -90,7 +90,7 @@ CLASS DOCUMENTATION
 @endcode
 
     @author Jon S. Berndt
-    @version $Id: FGAircraft.h,v 1.15 2009/10/24 22:59:30 jberndt Exp $
+    @version $Id: FGAircraft.h,v 1.16 2010/11/18 12:38:06 jberndt Exp $
     @see Cooke, Zyda, Pratt, and McGhee, "NPSNET: Flight Simulation Dynamic Modeling
 	   Using Quaternions", Presence, Vol. 1, No. 4, pp. 404-420  Naval Postgraduate
 	   School, January 1994
@@ -140,33 +140,33 @@ public:
   double GetWingSpan(void) const { return WingSpan; }
   /// Gets the average wing chord
   double Getcbar(void) const { return cbar; }
-  inline double GetWingIncidence(void) const { return WingIncidence; }
-  inline double GetWingIncidenceDeg(void) const { return WingIncidence*radtodeg; }
-  inline double GetHTailArea(void) const { return HTailArea; }
-  inline double GetHTailArm(void)  const { return HTailArm; }
-  inline double GetVTailArea(void) const { return VTailArea; }
-  inline double GetVTailArm(void)  const { return VTailArm; }
-  inline double Getlbarh(void) const { return lbarh; } // HTailArm / cbar
-  inline double Getlbarv(void) const { return lbarv; } // VTailArm / cbar
-  inline double Getvbarh(void) const { return vbarh; } // H. Tail Volume
-  inline double Getvbarv(void) const { return vbarv; } // V. Tail Volume
-  inline FGColumnVector3& GetMoments(void) { return vMoments; }
-  inline double GetMoments(int idx) const { return vMoments(idx); }
-  inline FGColumnVector3& GetForces(void) { return vForces; }
-  inline double GetForces(int idx) const { return vForces(idx); }
-  inline FGColumnVector3& GetBodyAccel(void) { return vBodyAccel; }
-  inline double GetBodyAccel(int idx) { return vBodyAccel(idx); }
-  inline FGColumnVector3& GetNcg   (void)  { return vNcg; }
-  inline double GetNcg(int idx)  { return vNcg(idx); }
-  inline FGColumnVector3& GetXYZrp(void) { return vXYZrp; }
-  inline FGColumnVector3& GetXYZvrp(void) { return vXYZvrp; }
-  inline FGColumnVector3& GetXYZep(void) { return vXYZep; }
-  inline double GetXYZrp(int idx) const { return vXYZrp(idx); }
-  inline double GetXYZvrp(int idx) const { return vXYZvrp(idx); }
-  inline double GetXYZep(int idx) const { return vXYZep(idx); }
-  inline void SetAircraftName(const std::string& name) {AircraftName = name;}
-  inline void SetHoldDown(int hd) {HoldDown = hd;}
-  inline int GetHoldDown(void) const {return HoldDown;}
+  double GetWingIncidence(void) const { return WingIncidence; }
+  double GetWingIncidenceDeg(void) const { return WingIncidence*radtodeg; }
+  double GetHTailArea(void) const { return HTailArea; }
+  double GetHTailArm(void)  const { return HTailArm; }
+  double GetVTailArea(void) const { return VTailArea; }
+  double GetVTailArm(void)  const { return VTailArm; }
+  double Getlbarh(void) const { return lbarh; } // HTailArm / cbar
+  double Getlbarv(void) const { return lbarv; } // VTailArm / cbar
+  double Getvbarh(void) const { return vbarh; } // H. Tail Volume
+  double Getvbarv(void) const { return vbarv; } // V. Tail Volume
+  const FGColumnVector3& GetMoments(void) const { return vMoments; }
+  double GetMoments(int idx) const { return vMoments(idx); }
+  const FGColumnVector3& GetForces(void) const { return vForces; }
+  double GetForces(int idx) const { return vForces(idx); }
+  FGColumnVector3& GetBodyAccel(void) { return vBodyAccel; }
+  double GetBodyAccel(int idx) const { return vBodyAccel(idx); }
+  const FGColumnVector3& GetNcg(void) const { return vNcg; }
+  double GetNcg(int idx) const { return vNcg(idx); }
+  const FGColumnVector3& GetXYZrp(void) const { return vXYZrp; }
+  const FGColumnVector3& GetXYZvrp(void) const { return vXYZvrp; }
+  const FGColumnVector3& GetXYZep(void) const { return vXYZep; }
+  double GetXYZrp(int idx) const { return vXYZrp(idx); }
+  double GetXYZvrp(int idx) const { return vXYZvrp(idx); }
+  double GetXYZep(int idx) const { return vXYZep(idx); }
+  void SetAircraftName(const std::string& name) {AircraftName = name;}
+  void SetHoldDown(int hd) {HoldDown = hd;}
+  int GetHoldDown(void) const {return HoldDown;}
 
   void SetXYZrp(int idx, double value) {vXYZrp(idx) = value;}
 
@@ -174,7 +174,7 @@ public:
 
   double GetNlf(void) const;
 
-  inline FGColumnVector3& GetNwcg(void) { return vNwcg; }
+  FGColumnVector3& GetNwcg(void) { return vNwcg; }
 
   void bind(void);
   void unbind(void);
diff --git a/src/FDM/JSBSim/models/FGAtmosphere.cpp b/src/FDM/JSBSim/models/FGAtmosphere.cpp
index 12fb084a7..d2c6a3dac 100644
--- a/src/FDM/JSBSim/models/FGAtmosphere.cpp
+++ b/src/FDM/JSBSim/models/FGAtmosphere.cpp
@@ -61,7 +61,7 @@ using namespace std;
 
 namespace JSBSim {
 
-static const char *IdSrc = "$Id: FGAtmosphere.cpp,v 1.38 2010/09/16 11:01:24 jberndt Exp $";
+static const char *IdSrc = "$Id: FGAtmosphere.cpp,v 1.40 2010/11/18 12:38:06 jberndt Exp $";
 static const char *IdHdr = ID_ATMOSPHERE;
 
 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@@ -158,7 +158,7 @@ bool FGAtmosphere::Run(void)
   RunPreFunctions();
 
   T_dev = 0.0;
-  h = Propagate->GetAltitudeASL();
+  h = FDMExec->GetPropagate()->GetAltitudeASL();
 
   if (!useExternal) {
     Calculate(h);
@@ -275,11 +275,11 @@ void FGAtmosphere::Calculate(double altitude)
 
   if (slope == 0) {
     intTemperature = reftemp;
-    intPressure = refpress*exp(-Inertial->SLgravity()/(reftemp*Reng)*(altitude-htab[i]));
+    intPressure = refpress*exp(-FDMExec->GetInertial()->SLgravity()/(reftemp*Reng)*(altitude-htab[i]));
     intDensity = intPressure/(Reng*intTemperature);
   } else {
     intTemperature = reftemp+slope*(altitude-htab[i]);
-    intPressure = refpress*pow(intTemperature/reftemp,-Inertial->SLgravity()/(slope*Reng));
+    intPressure = refpress*pow(intTemperature/reftemp,-FDMExec->GetInertial()->SLgravity()/(slope*Reng));
     intDensity = intPressure/(Reng*intTemperature);
   }
   
@@ -404,7 +404,12 @@ void FGAtmosphere::SetWindPsi(double dir)
 
 void FGAtmosphere::Turbulence(void)
 {
-  double DeltaT = rate*FDMExec->GetDeltaT();
+  const double DeltaT = rate*FDMExec->GetDeltaT();
+  const double wingspan = FDMExec->GetAircraft()->GetWingSpan();
+  const double HOverBMAC = FDMExec->GetAuxiliary()->GetHOverBMAC();
+  const FGMatrix33& Tl2b = FDMExec->GetPropagate()->GetTl2b();
+  const double HTailArm = FDMExec->GetAircraft()->GetHTailArm();
+  const double VTailArm = FDMExec->GetAircraft()->GetVTailArm();
 
   switch (turbType) {
   case ttStandard: {
@@ -438,7 +443,6 @@ void FGAtmosphere::Turbulence(void)
                                 // Diminish turbulence within three wingspans
                                 // of the ground
     vTurbulenceNED = TurbGain * Magnitude * vDirection;
-    double HOverBMAC = Auxiliary->GetHOverBMAC();
     if (HOverBMAC < 3.0)
         vTurbulenceNED *= (HOverBMAC / 3.0) * (HOverBMAC / 3.0);
 
@@ -451,20 +455,20 @@ void FGAtmosphere::Turbulence(void)
     // Need to determine the turbulence change in body axes between two time points.
 
     vTurbulenceGrad = TurbGain*MagnitudeAccel * vDirection;
-    vBodyTurbGrad = Propagate->GetTl2b()*vTurbulenceGrad;
+    vBodyTurbGrad = Tl2b*vTurbulenceGrad;
 
-    if (Aircraft->GetWingSpan() > 0) {
-      vTurbPQR(eP) = vBodyTurbGrad(eY)/Aircraft->GetWingSpan();
+    if (wingspan > 0) {
+      vTurbPQR(eP) = vBodyTurbGrad(eY)/wingspan;
     } else {
       vTurbPQR(eP) = vBodyTurbGrad(eY)/30.0;
     }
-//     if (Aircraft->GetHTailArm() != 0.0)
-//       vTurbPQR(eQ) = vBodyTurbGrad(eZ)/Aircraft->GetHTailArm();
+//     if (HTailArm != 0.0)
+//       vTurbPQR(eQ) = vBodyTurbGrad(eZ)/HTailArm;
 //     else
 //       vTurbPQR(eQ) = vBodyTurbGrad(eZ)/10.0;
 
-    if (Aircraft->GetVTailArm() > 0)
-      vTurbPQR(eR) = vBodyTurbGrad(eX)/Aircraft->GetVTailArm();
+    if (VTailArm > 0)
+      vTurbPQR(eR) = vBodyTurbGrad(eX)/VTailArm;
     else
       vTurbPQR(eR) = vBodyTurbGrad(eX)/10.0;
 
@@ -496,7 +500,6 @@ void FGAtmosphere::Turbulence(void)
     vDirection      += vDirectionAccel*DeltaT;
 
     // Diminish z-vector within two wingspans of the ground
-    double HOverBMAC = Auxiliary->GetHOverBMAC();
     if (HOverBMAC < 2.0) vDirection(eZ) *= HOverBMAC / 2.0;
 
     vDirection.Normalize();
@@ -504,15 +507,15 @@ void FGAtmosphere::Turbulence(void)
     vTurbulenceNED = TurbGain*Magnitude * vDirection;
     vTurbulenceGrad = TurbGain*MagnitudeAccel * vDirection;
 
-    vBodyTurbGrad = Propagate->GetTl2b() * vTurbulenceGrad;
-    vTurbPQR(eP) = vBodyTurbGrad(eY) / Aircraft->GetWingSpan();
-    if (Aircraft->GetHTailArm() > 0)
-      vTurbPQR(eQ) = vBodyTurbGrad(eZ) / Aircraft->GetHTailArm();
+    vBodyTurbGrad = Tl2b * vTurbulenceGrad;
+    vTurbPQR(eP) = vBodyTurbGrad(eY) / wingspan;
+    if (HTailArm > 0)
+      vTurbPQR(eQ) = vBodyTurbGrad(eZ) / HTailArm;
     else
       vTurbPQR(eQ) = vBodyTurbGrad(eZ) / 10.0;
 
-    if (Aircraft->GetVTailArm() > 0)
-      vTurbPQR(eR) = vBodyTurbGrad(eX) / Aircraft->GetVTailArm();
+    if (VTailArm > 0)
+      vTurbPQR(eR) = vBodyTurbGrad(eX) / VTailArm;
     else
       vTurbPQR(eR) = vBodyTurbGrad(eX)/10.0;
 
@@ -554,7 +557,6 @@ void FGAtmosphere::Turbulence(void)
     // Vertical component of turbulence.
     vTurbulenceNED(3) = sinewave * max_vs * TurbGain * Rhythmicity;
     vTurbulenceNED(3)+= delta;
-    double HOverBMAC = Auxiliary->GetHOverBMAC();
     if (HOverBMAC < 3.0)
         vTurbulenceNED(3) *= HOverBMAC * 0.3333;
  
@@ -579,9 +581,9 @@ void FGAtmosphere::Turbulence(void)
 
     // Turbulence model according to MIL-F-8785C (Flying Qualities of Piloted Aircraft)
     double
-      h = Propagate->GetDistanceAGL(),
-      V = Auxiliary->GetVt(), // true airspeed in ft/s
-      b_w = Aircraft->GetWingSpan(),
+      h = FDMExec->GetPropagate()->GetDistanceAGL(),
+      V = FDMExec->GetAuxiliary()->GetVt(), // true airspeed in ft/s
+      b_w = wingspan,
       L_u, L_w, sig_u, sig_w;
 
     // clip height functions at 10 ft
@@ -628,7 +630,7 @@ void FGAtmosphere::Turbulence(void)
       nu_v = GaussianRandomNumber(),
       nu_w = GaussianRandomNumber(),
       nu_p = GaussianRandomNumber(),
-      xi_u, xi_v, xi_w, xi_p, xi_q, xi_r;
+      xi_u=0, xi_v=0, xi_w=0, xi_p=0, xi_q=0, xi_r=0;
 
     // values of turbulence NED velocities
 
@@ -685,7 +687,7 @@ void FGAtmosphere::Turbulence(void)
     vTurbPQR(3) = xi_r;
 
     // vTurbPQR is in the body fixed frame, not NED
-    vTurbPQR = Propagate->GetTl2b()*vTurbPQR;
+    vTurbPQR = Tl2b*vTurbPQR;
 
     // hand on the values for the next timestep
     xi_u_km1 = xi_u; nu_u_km1 = nu_u;
diff --git a/src/FDM/JSBSim/models/FGAtmosphere.h b/src/FDM/JSBSim/models/FGAtmosphere.h
index d6561fa86..3dd6fa322 100644
--- a/src/FDM/JSBSim/models/FGAtmosphere.h
+++ b/src/FDM/JSBSim/models/FGAtmosphere.h
@@ -35,8 +35,8 @@ HISTORY
 SENTRY
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
 
-#ifndef FGAtmosphere_H
-#define FGAtmosphere_H
+#ifndef FGATMOSPHERE_H
+#define FGATMOSPHERE_H
 
 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 INCLUDES
@@ -50,7 +50,7 @@ INCLUDES
 DEFINITIONS
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
 
-#define ID_ATMOSPHERE "$Id: FGAtmosphere.h,v 1.23 2010/09/16 11:01:24 jberndt Exp $"
+#define ID_ATMOSPHERE "$Id: FGAtmosphere.h,v 1.24 2010/11/18 12:38:06 jberndt Exp $"
 
 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 FORWARD DECLARATIONS
@@ -64,7 +64,7 @@ CLASS DOCUMENTATION
 
 /** Models the 1976 Standard Atmosphere.
     @author Tony Peden, Jon Berndt
-    @version $Id: FGAtmosphere.h,v 1.23 2010/09/16 11:01:24 jberndt Exp $
+    @version $Id: FGAtmosphere.h,v 1.24 2010/11/18 12:38:06 jberndt Exp $
     @see Anderson, John D. "Introduction to Flight, Third Edition", McGraw-Hill,
          1989, ISBN 0-07-001641-0
 
@@ -205,7 +205,7 @@ public:
   // TOTAL WIND access functions (wind + gust + turbulence)
 
   /// Retrieves the total wind components in NED frame.
-  FGColumnVector3& GetTotalWindNED(void) { return vTotalWindNED; }
+  const FGColumnVector3& GetTotalWindNED(void) const { return vTotalWindNED; }
 
   /// Retrieves a total wind component in NED frame.
   double GetTotalWindNED(int idx) const {return vTotalWindNED(idx);}
@@ -276,8 +276,8 @@ public:
 
   double GetTurbPQR(int idx) const {return vTurbPQR(idx);}
   double GetTurbMagnitude(void) const {return Magnitude;}
-  FGColumnVector3& GetTurbDirection(void) {return vDirection;}
-  FGColumnVector3& GetTurbPQR(void) {return vTurbPQR;}
+  const FGColumnVector3& GetTurbDirection(void) const {return vDirection;}
+  const FGColumnVector3& GetTurbPQR(void) const {return vTurbPQR;}
 
   void   SetWindspeed20ft(double ws) { windspeed_at_20ft = ws;}
   double GetWindspeed20ft() const { return windspeed_at_20ft;}
diff --git a/src/FDM/JSBSim/models/FGAuxiliary.cpp b/src/FDM/JSBSim/models/FGAuxiliary.cpp
index 630a9712a..1dd3e2207 100755
--- a/src/FDM/JSBSim/models/FGAuxiliary.cpp
+++ b/src/FDM/JSBSim/models/FGAuxiliary.cpp
@@ -59,7 +59,7 @@ using namespace std;
 
 namespace JSBSim {
 
-static const char *IdSrc = "$Id: FGAuxiliary.cpp,v 1.44 2010/10/10 15:10:15 jberndt Exp $";
+static const char *IdSrc = "$Id: FGAuxiliary.cpp,v 1.45 2010/11/18 12:38:06 jberndt Exp $";
 static const char *IdHdr = ID_AUXILIARY;
 
 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@@ -144,22 +144,29 @@ bool FGAuxiliary::Run()
 
   RunPreFunctions();
 
-  const FGColumnVector3& vPQR = Propagate->GetPQR();
-  const FGColumnVector3& vUVW = Propagate->GetUVW();
-  const FGColumnVector3& vUVWdot = Propagate->GetUVWdot();
-  const FGColumnVector3& vVel = Propagate->GetVel();
+  const double density = FDMExec->GetAtmosphere()->GetDensity();
+  const double soundspeed = FDMExec->GetAtmosphere()->GetSoundSpeed();
+  const double DistanceAGL = FDMExec->GetPropagate()->GetDistanceAGL();
+  const double wingspan = FDMExec->GetAircraft()->GetWingSpan();
+  const FGMatrix33& Tl2b = FDMExec->GetPropagate()->GetTl2b();
+  const FGMatrix33& Tb2l = FDMExec->GetPropagate()->GetTb2l();
 
-  p = Atmosphere->GetPressure();
-  rhosl = Atmosphere->GetDensitySL();
-  psl = Atmosphere->GetPressureSL();
-  sat = Atmosphere->GetTemperature();
+  const FGColumnVector3& vPQR = FDMExec->GetPropagate()->GetPQR();
+  const FGColumnVector3& vUVW = FDMExec->GetPropagate()->GetUVW();
+  const FGColumnVector3& vUVWdot = FDMExec->GetPropagate()->GetUVWdot();
+  const FGColumnVector3& vVel = FDMExec->GetPropagate()->GetVel();
+
+  p = FDMExec->GetAtmosphere()->GetPressure();
+  rhosl = FDMExec->GetAtmosphere()->GetDensitySL();
+  psl = FDMExec->GetAtmosphere()->GetPressureSL();
+  sat = FDMExec->GetAtmosphere()->GetTemperature();
 
 // Rotation
 
-  double cTht = Propagate->GetCosEuler(eTht);
-  double sTht = Propagate->GetSinEuler(eTht);
-  double cPhi = Propagate->GetCosEuler(ePhi);
-  double sPhi = Propagate->GetSinEuler(ePhi);
+  double cTht = FDMExec->GetPropagate()->GetCosEuler(eTht);
+  double sTht = FDMExec->GetPropagate()->GetSinEuler(eTht);
+  double cPhi = FDMExec->GetPropagate()->GetCosEuler(ePhi);
+  double sPhi = FDMExec->GetPropagate()->GetSinEuler(ePhi);
 
   vEulerRates(eTht) = vPQR(eQ)*cPhi - vPQR(eR)*sPhi;
   if (cTht != 0.0) {
@@ -168,8 +175,8 @@ bool FGAuxiliary::Run()
   }
 
 // Combine the wind speed with aircraft speed to obtain wind relative speed
-  FGColumnVector3 wind = Propagate->GetTl2b()*Atmosphere->GetTotalWindNED();
-  vAeroPQR = vPQR - Atmosphere->GetTurbPQR();
+  FGColumnVector3 wind = Tl2b*FDMExec->GetAtmosphere()->GetTotalWindNED();
+  vAeroPQR = vPQR - FDMExec->GetAtmosphere()->GetTurbPQR();
   vAeroUVW = vUVW - wind;
 
   Vt = vAeroUVW.Magnitude();
@@ -196,15 +203,15 @@ bool FGAuxiliary::Run()
     alpha = beta = adot = bdot = 0;
   }
 
-  Re = Vt * Aircraft->Getcbar() / Atmosphere->GetKinematicViscosity();
+  Re = Vt * FDMExec->GetAircraft()->Getcbar() / FDMExec->GetAtmosphere()->GetKinematicViscosity();
 
-  qbar = 0.5*Atmosphere->GetDensity()*Vt*Vt;
-  qbarUW = 0.5*Atmosphere->GetDensity()*(vAeroUVW(eU)*vAeroUVW(eU) + vAeroUVW(eW)*vAeroUVW(eW));
-  qbarUV = 0.5*Atmosphere->GetDensity()*(vAeroUVW(eU)*vAeroUVW(eU) + vAeroUVW(eV)*vAeroUVW(eV));
-  Mach = Vt / Atmosphere->GetSoundSpeed();
-  MachU = vMachUVW(eU) = vAeroUVW(eU) / Atmosphere->GetSoundSpeed();
-  vMachUVW(eV) = vAeroUVW(eV) / Atmosphere->GetSoundSpeed();
-  vMachUVW(eW) = vAeroUVW(eW) / Atmosphere->GetSoundSpeed();
+  qbar = 0.5*density*Vt*Vt;
+  qbarUW = 0.5*density*(vAeroUVW(eU)*vAeroUVW(eU) + vAeroUVW(eW)*vAeroUVW(eW));
+  qbarUV = 0.5*density*(vAeroUVW(eU)*vAeroUVW(eU) + vAeroUVW(eV)*vAeroUVW(eV));
+  Mach = Vt / soundspeed;
+  MachU = vMachUVW(eU) = vAeroUVW(eU) / soundspeed;
+  vMachUVW(eV) = vAeroUVW(eV) / soundspeed;
+  vMachUVW(eW) = vAeroUVW(eW) / soundspeed;
 
 // Position
 
@@ -234,20 +241,15 @@ bool FGAuxiliary::Run()
     vcas = veas = 0.0;
   }
 
+  const double SLgravity = FDMExec->GetInertial()->SLgravity();
+
   vPilotAccel.InitMatrix();
   if ( Vt > 1.0 ) {
-     // Use the "+=" operator to avoid the creation of temporary objects.
-     vAircraftAccel = Aerodynamics->GetForces();
-     vAircraftAccel += Propulsion->GetForces();
-     vAircraftAccel += GroundReactions->GetForces();
-     vAircraftAccel += ExternalReactions->GetForces();
-     vAircraftAccel += BuoyantForces->GetForces();
-
-     vAircraftAccel /= MassBalance->GetMass();
+     vAircraftAccel = FDMExec->GetAircraft()->GetBodyAccel();
      // Nz is Acceleration in "g's", along normal axis (-Z body axis)
-     Nz = -vAircraftAccel(eZ)/Inertial->SLgravity();
-     vToEyePt = MassBalance->StructuralToBody(Aircraft->GetXYZep());
-     vPilotAccel = vAircraftAccel + Propagate->GetPQRdot() * vToEyePt;
+     Nz = -vAircraftAccel(eZ)/SLgravity;
+     vToEyePt = FDMExec->GetMassBalance()->StructuralToBody(FDMExec->GetAircraft()->GetXYZep());
+     vPilotAccel = vAircraftAccel + FDMExec->GetPropagate()->GetPQRdot() * vToEyePt;
      vPilotAccel += vPQR * (vPQR * vToEyePt);
   } else {
      // The line below handles low velocity (and on-ground) cases, basically
@@ -256,24 +258,24 @@ bool FGAuxiliary::Run()
      // any jitter that could be introduced by the landing gear. Theoretically,
      // this branch could be eliminated, with a penalty of having a short
      // transient at startup (lasting only a fraction of a second).
-     vPilotAccel = Propagate->GetTl2b() * FGColumnVector3( 0.0, 0.0, -Inertial->SLgravity() );
-     Nz = -vPilotAccel(eZ)/Inertial->SLgravity();
+     vPilotAccel = Tl2b * FGColumnVector3( 0.0, 0.0, -SLgravity );
+     Nz = -vPilotAccel(eZ)/SLgravity;
   }
 
-  vPilotAccelN = vPilotAccel/Inertial->SLgravity();
+  vPilotAccelN = vPilotAccel/SLgravity;
 
   // VRP computation
-  const FGLocation& vLocation = Propagate->GetLocation();
-  FGColumnVector3& vrpStructural = Aircraft->GetXYZvrp();
-  FGColumnVector3 vrpBody = MassBalance->StructuralToBody( vrpStructural );
-  FGColumnVector3 vrpLocal = Propagate->GetTb2l() * vrpBody;
+  const FGLocation& vLocation = FDMExec->GetPropagate()->GetLocation();
+  const FGColumnVector3& vrpStructural = FDMExec->GetAircraft()->GetXYZvrp();
+  const FGColumnVector3 vrpBody = FDMExec->GetMassBalance()->StructuralToBody( vrpStructural );
+  const FGColumnVector3 vrpLocal = Tb2l * vrpBody;
   vLocationVRP = vLocation.LocalToLocation( vrpLocal );
 
   // Recompute some derived values now that we know the dependent parameters values ...
-  hoverbcg = Propagate->GetDistanceAGL() / Aircraft->GetWingSpan();
+  hoverbcg = DistanceAGL / wingspan;
 
-  FGColumnVector3 vMac = Propagate->GetTb2l()*MassBalance->StructuralToBody(Aircraft->GetXYZrp());
-  hoverbmac = (Propagate->GetDistanceAGL() + vMac(3)) / Aircraft->GetWingSpan();
+  FGColumnVector3 vMac = Tb2l*FDMExec->GetMassBalance()->StructuralToBody(FDMExec->GetAircraft()->GetXYZrp());
+  hoverbmac = (DistanceAGL + vMac(3)) / wingspan;
 
   // when all model are executed, 
   // please calculate the distance from the initial point
@@ -294,10 +296,10 @@ double FGAuxiliary::GetHeadWind(void) const
 {
   double psiw,vw;
 
-  psiw = Atmosphere->GetWindPsi();
-  vw = Atmosphere->GetTotalWindNED().Magnitude();
+  psiw = FDMExec->GetAtmosphere()->GetWindPsi();
+  vw = FDMExec->GetAtmosphere()->GetTotalWindNED().Magnitude();
 
-  return vw*cos(psiw - Propagate->GetEuler(ePsi));
+  return vw*cos(psiw - FDMExec->GetPropagate()->GetEuler(ePsi));
 }
 
 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@@ -310,10 +312,17 @@ double FGAuxiliary::GetCrossWind(void) const
 {
   double psiw,vw;
 
-  psiw = Atmosphere->GetWindPsi();
-  vw = Atmosphere->GetTotalWindNED().Magnitude();
+  psiw = FDMExec->GetAtmosphere()->GetWindPsi();
+  vw = FDMExec->GetAtmosphere()->GetTotalWindNED().Magnitude();
 
-  return  vw*sin(psiw - Propagate->GetEuler(ePsi));
+  return  vw*sin(psiw - FDMExec->GetPropagate()->GetEuler(ePsi));
+}
+
+//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+double FGAuxiliary::GethVRP(void) const
+{
+  return vLocationVRP.GetRadius() - FDMExec->GetPropagate()->GetSeaLevelRadius();
 }
 
 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@@ -382,7 +391,7 @@ void FGAuxiliary::bind(void)
 
 void FGAuxiliary::CalculateRelativePosition(void)
 { 
-  const double earth_radius_mt = Inertial->GetRefRadius()*fttom;
+  const double earth_radius_mt = FDMExec->GetInertial()->GetRefRadius()*fttom;
   lat_relative_position=(FDMExec->GetPropagate()->GetLatitude()  - FDMExec->GetIC()->GetLatitudeDegIC() *degtorad)*earth_radius_mt;
   lon_relative_position=(FDMExec->GetPropagate()->GetLongitude() - FDMExec->GetIC()->GetLongitudeDegIC()*degtorad)*earth_radius_mt;
   relative_position = sqrt(lat_relative_position*lat_relative_position + lon_relative_position*lon_relative_position);
diff --git a/src/FDM/JSBSim/models/FGAuxiliary.h b/src/FDM/JSBSim/models/FGAuxiliary.h
index d86cc5f11..8f7821245 100644
--- a/src/FDM/JSBSim/models/FGAuxiliary.h
+++ b/src/FDM/JSBSim/models/FGAuxiliary.h
@@ -42,13 +42,12 @@ INCLUDES
 #include "FGModel.h"
 #include "math/FGColumnVector3.h"
 #include "math/FGLocation.h"
-#include "FGPropagate.h"
 
 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 DEFINITIONS
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
 
-#define ID_AUXILIARY "$Id: FGAuxiliary.h,v 1.17 2009/10/24 22:59:30 jberndt Exp $"
+#define ID_AUXILIARY "$Id: FGAuxiliary.h,v 1.19 2010/11/18 12:38:06 jberndt Exp $"
 
 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 FORWARD DECLARATIONS
@@ -100,7 +99,7 @@ CLASS DOCUMENTATION
     The radius R is calculated below in the vector vToEyePt.
 
     @author Tony Peden, Jon Berndt
-    @version $Id: FGAuxiliary.h,v 1.17 2009/10/24 22:59:30 jberndt Exp $
+    @version $Id: FGAuxiliary.h,v 1.19 2010/11/18 12:38:06 jberndt Exp $
 */
 
 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@@ -162,7 +161,7 @@ public:
   const FGColumnVector3& GetAeroUVW    (void) const { return vAeroUVW;     }
   const FGLocation&      GetLocationVRP(void) const { return vLocationVRP; }
 
-  double GethVRP(void) const { return vLocationVRP.GetRadius() - Propagate->GetSeaLevelRadius(); }
+  double GethVRP(void) const;
   double GetAeroUVW (int idx) const { return vAeroUVW(idx); }
   double Getalpha   (void) const { return alpha;      }
   double Getbeta    (void) const { return beta;       }
diff --git a/src/FDM/JSBSim/models/FGBuoyantForces.cpp b/src/FDM/JSBSim/models/FGBuoyantForces.cpp
index 1b9a63b74..b3808d70f 100644
--- a/src/FDM/JSBSim/models/FGBuoyantForces.cpp
+++ b/src/FDM/JSBSim/models/FGBuoyantForces.cpp
@@ -45,7 +45,7 @@ using namespace std;
 
 namespace JSBSim {
 
-static const char *IdSrc = "$Id: FGBuoyantForces.cpp,v 1.13 2010/09/07 00:40:03 jberndt Exp $";
+static const char *IdSrc = "$Id: FGBuoyantForces.cpp,v 1.14 2010/11/18 12:38:06 jberndt Exp $";
 static const char *IdHdr = ID_BUOYANTFORCES;
 
 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@@ -181,7 +181,7 @@ const FGMatrix33& FGBuoyantForces::GetGasMassInertia(void)
   gasCellJ = FGMatrix33();
 
   for (unsigned int i=0; i < size; i++) {
-    FGColumnVector3 v = MassBalance->StructuralToBody( Cells[i]->GetXYZ() );
+    FGColumnVector3 v = FDMExec->GetMassBalance()->StructuralToBody( Cells[i]->GetXYZ() );
     // Body basis is in FT. 
     const double mass = Cells[i]->GetMass();
     
diff --git a/src/FDM/JSBSim/models/FGExternalForce.h b/src/FDM/JSBSim/models/FGExternalForce.h
index f1a6a41ac..5ece2bf22 100755
--- a/src/FDM/JSBSim/models/FGExternalForce.h
+++ b/src/FDM/JSBSim/models/FGExternalForce.h
@@ -39,10 +39,10 @@ SENTRY
 INCLUDES
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
 
+#include <string>
 #include "FGFDMExec.h"
 #include "FGJSBBase.h"
 #include "models/propulsion/FGForce.h"
-#include <string>
 #include "input_output/FGPropertyManager.h"
 #include "math/FGColumnVector3.h"
 #include "math/FGFunction.h"
@@ -51,7 +51,7 @@ INCLUDES
 DEFINITIONS
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
 
-#define ID_EXTERNALFORCE "$Id: FGExternalForce.h,v 1.8 2009/10/02 10:30:09 jberndt Exp $"
+#define ID_EXTERNALFORCE "$Id: FGExternalForce.h,v 1.9 2010/11/18 12:38:06 jberndt Exp $"
 
 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 FORWARD DECLARATIONS
diff --git a/src/FDM/JSBSim/models/FGExternalReactions.h b/src/FDM/JSBSim/models/FGExternalReactions.h
index 10ad35d07..4b7df2d85 100755
--- a/src/FDM/JSBSim/models/FGExternalReactions.h
+++ b/src/FDM/JSBSim/models/FGExternalReactions.h
@@ -38,15 +38,15 @@ SENTRY
 INCLUDES
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
 
+#include <vector>
 #include "FGModel.h"
 #include "FGExternalForce.h"
-#include <vector>
 
 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 DEFINITIONS
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
 
-#define ID_EXTERNALREACTIONS "$Id: FGExternalReactions.h,v 1.9 2009/10/24 22:59:30 jberndt Exp $"
+#define ID_EXTERNALREACTIONS "$Id: FGExternalReactions.h,v 1.10 2010/11/18 12:38:06 jberndt Exp $"
 
 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 FORWARD DECLARATIONS
@@ -147,12 +147,12 @@ public:
   /** Retrieves the total forces defined in the external reactions.
       @return the total force in pounds.
   */
-  FGColumnVector3 GetForces(void) {return vTotalForces;}
+  FGColumnVector3 GetForces(void) const {return vTotalForces;}
 
   /** Retrieves the total moment resulting from the forces defined in the external reactions.
       @return the total moment in foot-pounds.
   */
-  FGColumnVector3 GetMoments(void) {return vTotalMoments;}
+  FGColumnVector3 GetMoments(void) const {return vTotalMoments;}
 
 private:
 
diff --git a/src/FDM/JSBSim/models/FGFCS.cpp b/src/FDM/JSBSim/models/FGFCS.cpp
index 3de0c7135..f0b77007d 100644
--- a/src/FDM/JSBSim/models/FGFCS.cpp
+++ b/src/FDM/JSBSim/models/FGFCS.cpp
@@ -63,7 +63,7 @@ using namespace std;
 
 namespace JSBSim {
 
-static const char *IdSrc = "$Id: FGFCS.cpp,v 1.71 2010/09/28 02:54:03 jberndt Exp $";
+static const char *IdSrc = "$Id: FGFCS.cpp,v 1.72 2010/11/18 12:38:06 jberndt Exp $";
 static const char *IdHdr = ID_FCS;
 
 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@@ -218,7 +218,7 @@ bool FGFCS::Run(void)
 
   // Set the default steering angle
   for (i=0; i<SteerPosDeg.size(); i++) {
-    FGLGear* gear = GroundReactions->GetGearUnit(i);
+    FGLGear* gear = FDMExec->GetGroundReactions()->GetGearUnit(i);
     SteerPosDeg[i] = gear->GetDefaultSteerAngle( GetDsCmd() );
   }
 
@@ -760,7 +760,7 @@ ifstream* FGFCS::FindSystemFile(const string& sysfilename)
 
 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
-string FGFCS::GetComponentStrings(const string& delimiter)
+string FGFCS::GetComponentStrings(const string& delimiter) const
 {
   unsigned int comp;
   string CompStrings = "";
@@ -797,7 +797,7 @@ string FGFCS::GetComponentStrings(const string& delimiter)
 
 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
-string FGFCS::GetComponentValues(const string& delimiter)
+string FGFCS::GetComponentValues(const string& delimiter) const
 {
   std::ostringstream buf;
 
@@ -964,7 +964,7 @@ void FGFCS::bindModel(void)
   string tmp;
 
   for (i=0; i<SteerPosDeg.size(); i++) {
-    if (GroundReactions->GetGearUnit(i)->GetSteerable()) {
+    if (FDMExec->GetGroundReactions()->GetGearUnit(i)->GetSteerable()) {
       tmp = CreateIndexedPropertyName("fcs/steer-pos-deg", i);
       PropertyManager->Tie( tmp.c_str(), this, i, &FGFCS::GetSteerPosDeg, &FGFCS::SetSteerPosDeg);
     }
diff --git a/src/FDM/JSBSim/models/FGFCS.h b/src/FDM/JSBSim/models/FGFCS.h
index 1a57835f9..a17509212 100644
--- a/src/FDM/JSBSim/models/FGFCS.h
+++ b/src/FDM/JSBSim/models/FGFCS.h
@@ -348,13 +348,13 @@ public:
   /** Retrieves all component names for inclusion in output stream
       @param delimiter either a tab or comma string depending on output type
       @return a string containing the descriptive names for all components */
-  std::string GetComponentStrings(const std::string& delimiter);
+  std::string GetComponentStrings(const std::string& delimiter) const;
 
   /** Retrieves all component outputs for inclusion in output stream
       @param delimiter either a tab or comma string depending on output type
       @return a string containing the numeric values for the current set of
       component outputs */
-  std::string GetComponentValues(const std::string& delimiter);
+  std::string GetComponentValues(const std::string& delimiter) const;
 
   /// @name Pilot input command setting
   //@{
diff --git a/src/FDM/JSBSim/models/FGGroundReactions.cpp b/src/FDM/JSBSim/models/FGGroundReactions.cpp
index 246cefe8c..9126c9f81 100644
--- a/src/FDM/JSBSim/models/FGGroundReactions.cpp
+++ b/src/FDM/JSBSim/models/FGGroundReactions.cpp
@@ -46,7 +46,7 @@ using namespace std;
 
 namespace JSBSim {
 
-static const char *IdSrc = "$Id: FGGroundReactions.cpp,v 1.30 2010/09/07 00:40:03 jberndt Exp $";
+static const char *IdSrc = "$Id: FGGroundReactions.cpp,v 1.31 2010/11/18 12:38:06 jberndt Exp $";
 static const char *IdHdr = ID_GROUNDREACTIONS;
 
 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@@ -187,7 +187,7 @@ bool FGGroundReactions::Load(Element* el)
   Element* contact_element = el->FindElement("contact");
   while (contact_element) {
     lGear.push_back(new FGLGear(contact_element, FDMExec, num++));
-    FCS->AddGear(); // make the FCS aware of the landing gear
+    FDMExec->GetFCS()->AddGear(); // make the FCS aware of the landing gear
     contact_element = el->FindNextElement("contact");
   }
   
@@ -202,7 +202,7 @@ bool FGGroundReactions::Load(Element* el)
 
 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
-string FGGroundReactions::GetGroundReactionStrings(string delimeter)
+string FGGroundReactions::GetGroundReactionStrings(string delimeter) const
 {
   std::ostringstream buf;
 
@@ -237,7 +237,7 @@ string FGGroundReactions::GetGroundReactionStrings(string delimeter)
 
 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
-string FGGroundReactions::GetGroundReactionValues(string delimeter)
+string FGGroundReactions::GetGroundReactionValues(string delimeter) const
 {
   std::ostringstream buf;
 
diff --git a/src/FDM/JSBSim/models/FGGroundReactions.h b/src/FDM/JSBSim/models/FGGroundReactions.h
index a10ff0bb1..30792225d 100644
--- a/src/FDM/JSBSim/models/FGGroundReactions.h
+++ b/src/FDM/JSBSim/models/FGGroundReactions.h
@@ -45,7 +45,7 @@ INCLUDES
 #include "math/FGColumnVector3.h"
 #include "input_output/FGXMLElement.h"
 
-#define ID_GROUNDREACTIONS "$Id: FGGroundReactions.h,v 1.18 2010/09/07 00:40:03 jberndt Exp $"
+#define ID_GROUNDREACTIONS "$Id: FGGroundReactions.h,v 1.19 2010/11/18 12:38:06 jberndt Exp $"
 
 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 FORWARD DECLARATIONS
@@ -100,12 +100,12 @@ public:
   bool InitModel(void);
   bool Run(void);
   bool Load(Element* el);
-  FGColumnVector3& GetForces(void) {return vForces;}
+  const FGColumnVector3& GetForces(void) const {return vForces;}
   double GetForces(int idx) const {return vForces(idx);}
-  FGColumnVector3& GetMoments(void) {return vMoments;}
+  const FGColumnVector3& GetMoments(void) const {return vMoments;}
   double GetMoments(int idx) const {return vMoments(idx);}
-  string GetGroundReactionStrings(string delimeter);
-  string GetGroundReactionValues(string delimeter);
+  string GetGroundReactionStrings(string delimeter) const;
+  string GetGroundReactionValues(string delimeter) const;
   bool GetWOW(void) const;
   void UpdateForcesAndMoments(void);
 
@@ -114,7 +114,7 @@ public:
   /** Gets a gear instance
       @param gear index of gear instance
       @return a pointer to the FGLGear instance of the gear unit requested */
-  inline FGLGear* GetGearUnit(int gear) { return lGear[gear]; }
+  FGLGear* GetGearUnit(int gear) const { return lGear[gear]; }
 
 private:
   vector <FGLGear*> lGear;
diff --git a/src/FDM/JSBSim/models/FGInertial.cpp b/src/FDM/JSBSim/models/FGInertial.cpp
index 0779c6954..94aa291c3 100644
--- a/src/FDM/JSBSim/models/FGInertial.cpp
+++ b/src/FDM/JSBSim/models/FGInertial.cpp
@@ -45,7 +45,7 @@ using namespace std;
 
 namespace JSBSim {
 
-static const char *IdSrc = "$Id: FGInertial.cpp,v 1.19 2010/10/10 15:06:38 jberndt Exp $";
+static const char *IdSrc = "$Id: FGInertial.cpp,v 1.20 2010/11/18 12:38:06 jberndt Exp $";
 static const char *IdHdr = ID_INERTIAL;
 
 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@@ -116,7 +116,7 @@ bool FGInertial::Run(void)
   RunPreFunctions();
 
   // Gravitation accel
-  double r = Propagate->GetRadius();
+  double r = FDMExec->GetPropagate()->GetRadius();
   gAccel = GetGAccel(r);
   earthPosAngle += FDMExec->GetDeltaT()*RotationRate;
 
@@ -145,7 +145,7 @@ FGColumnVector3 FGInertial::GetGravityJ2(FGColumnVector3 position) const
 
   // Gravitation accel
   double r = position.Magnitude();
-  double lat = Propagate->GetLatitude();
+  double lat = FDMExec->GetPropagate()->GetLatitude();
   double sinLat = sin(lat);
 
   double adivr = a/r;
diff --git a/src/FDM/JSBSim/models/FGInput.cpp b/src/FDM/JSBSim/models/FGInput.cpp
index c8cc13b83..65ab24db2 100755
--- a/src/FDM/JSBSim/models/FGInput.cpp
+++ b/src/FDM/JSBSim/models/FGInput.cpp
@@ -191,7 +191,7 @@ bool FGInput::Run(void)
         ostringstream info;
         info << "JSBSim version: " << JSBSim_version << endl;
         info << "Config File version: " << needed_cfg_version << endl;
-        info << "Aircraft simulated: " << Aircraft->GetAircraftName() << endl;
+//      info << "Aircraft simulated: " << Aircraft->GetAircraftName() << endl;
         info << "Simulation time: " << setw(8) << setprecision(3) << FDMExec->GetSimTime() << endl;
         socket->Reply(info.str());
 
diff --git a/src/FDM/JSBSim/models/FGMassBalance.cpp b/src/FDM/JSBSim/models/FGMassBalance.cpp
index 95608f6bf..fd067ab51 100644
--- a/src/FDM/JSBSim/models/FGMassBalance.cpp
+++ b/src/FDM/JSBSim/models/FGMassBalance.cpp
@@ -51,7 +51,7 @@ using namespace std;
 
 namespace JSBSim {
 
-static const char *IdSrc = "$Id: FGMassBalance.cpp,v 1.33 2010/09/07 00:40:03 jberndt Exp $";
+static const char *IdSrc = "$Id: FGMassBalance.cpp,v 1.34 2010/11/18 12:38:06 jberndt Exp $";
 static const char *IdHdr = ID_MASSBALANCE;
 
 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@@ -151,8 +151,8 @@ bool FGMassBalance::Load(Element* el)
     if (FDMExec->GetChildFDM(fdm)->mated) ChildFDMWeight += FDMExec->GetChildFDM(fdm)->exec->GetMassBalance()->GetWeight();
   }
 
-  Weight = EmptyWeight + Propulsion->GetTanksWeight() + GetTotalPointMassWeight()
-    + BuoyantForces->GetGasMass()*slugtolb + ChildFDMWeight;
+  Weight = EmptyWeight + FDMExec->GetPropulsion()->GetTanksWeight() + GetTotalPointMassWeight()
+    + FDMExec->GetBuoyantForces()->GetGasMass()*slugtolb + ChildFDMWeight;
 
   Mass = lbtoslug*Weight;
 
@@ -179,16 +179,16 @@ bool FGMassBalance::Run(void)
     if (FDMExec->GetChildFDM(fdm)->mated) ChildFDMWeight += FDMExec->GetChildFDM(fdm)->exec->GetMassBalance()->GetWeight();
   }
 
-  Weight = EmptyWeight + Propulsion->GetTanksWeight() + GetTotalPointMassWeight()
-    + BuoyantForces->GetGasMass()*slugtolb + ChildFDMWeight;
+  Weight = EmptyWeight + FDMExec->GetPropulsion()->GetTanksWeight() + GetTotalPointMassWeight()
+    + FDMExec->GetBuoyantForces()->GetGasMass()*slugtolb + ChildFDMWeight;
 
   Mass = lbtoslug*Weight;
 
 // Calculate new CG
 
-  vXYZcg = (Propulsion->GetTanksMoment() + EmptyWeight*vbaseXYZcg
+  vXYZcg = (FDMExec->GetPropulsion()->GetTanksMoment() + EmptyWeight*vbaseXYZcg
             + GetPointMassMoment()
-            + BuoyantForces->GetGasMassMoment()) / Weight;
+            + FDMExec->GetBuoyantForces()->GetGasMassMoment()) / Weight;
 
   // Track frame-by-frame delta CG, and move the EOM-tracked location
   // by this amount.
@@ -196,7 +196,7 @@ bool FGMassBalance::Run(void)
   vDeltaXYZcg = vXYZcg - vLastXYZcg;
   vDeltaXYZcgBody = StructuralToBody(vLastXYZcg) - StructuralToBody(vXYZcg);
   vLastXYZcg = vXYZcg;
-  Propagate->NudgeBodyLocation(vDeltaXYZcgBody);
+  FDMExec->GetPropagate()->NudgeBodyLocation(vDeltaXYZcgBody);
 
 // Calculate new total moments of inertia
 
@@ -206,8 +206,8 @@ bool FGMassBalance::Run(void)
   mJ += GetPointmassInertia( lbtoslug * EmptyWeight, vbaseXYZcg );
   // Then add the contributions from the additional pointmasses.
   mJ += CalculatePMInertias();
-  mJ += Propulsion->CalculateTankInertias();
-  mJ += BuoyantForces->GetGasMassInertia();
+  mJ += FDMExec->GetPropulsion()->CalculateTankInertias();
+  mJ += FDMExec->GetBuoyantForces()->GetGasMassInertia();
 
   Ixx = mJ(1,1);
   Iyy = mJ(2,2);
@@ -432,8 +432,8 @@ void FGMassBalance::GetMassPropertiesReport(void) const
          << setw(12) << pm->GetPointMassMoI(3,3) << endl;
   }
 
-  for (unsigned int i=0;i<Propulsion->GetNumTanks() ;i++) {
-    FGTank* tank = Propulsion->GetTank(i);
+  for (unsigned int i=0;i<FDMExec->GetPropulsion()->GetNumTanks() ;i++) {
+    FGTank* tank = FDMExec->GetPropulsion()->GetTank(i);
     string tankname="";
     if (tank->GetType() == FGTank::ttFUEL && tank->GetGrainType() != FGTank::gtUNKNOWN) {
       tankname = "Solid Fuel";
diff --git a/src/FDM/JSBSim/models/FGMassBalance.h b/src/FDM/JSBSim/models/FGMassBalance.h
index be461a1e8..c7468c5db 100644
--- a/src/FDM/JSBSim/models/FGMassBalance.h
+++ b/src/FDM/JSBSim/models/FGMassBalance.h
@@ -49,7 +49,7 @@ INCLUDES
 DEFINITIONS
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
 
-#define ID_MASSBALANCE "$Id: FGMassBalance.h,v 1.21 2010/08/12 04:07:11 jberndt Exp $"
+#define ID_MASSBALANCE "$Id: FGMassBalance.h,v 1.22 2010/11/18 12:38:06 jberndt Exp $"
 
 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 FORWARD DECLARATIONSS
@@ -160,15 +160,15 @@ public:
    */
   FGColumnVector3 StructuralToBody(const FGColumnVector3& r) const;
 
-  inline void SetEmptyWeight(double EW) { EmptyWeight = EW;}
-  inline void SetBaseCG(const FGColumnVector3& CG) {vbaseXYZcg = vXYZcg = CG;}
+  void SetEmptyWeight(double EW) { EmptyWeight = EW;}
+  void SetBaseCG(const FGColumnVector3& CG) {vbaseXYZcg = vXYZcg = CG;}
 
   void AddPointMass(Element* el);
   double GetTotalPointMassWeight(void);
 
   FGColumnVector3& GetPointMassMoment(void);
-  FGMatrix33& GetJ(void) {return mJ;}
-  FGMatrix33& GetJinv(void) {return mJinv;}
+  const FGMatrix33& GetJ(void) const {return mJ;}
+  const FGMatrix33& GetJinv(void) const {return mJinv;}
   void SetAircraftBaseInertias(FGMatrix33 BaseJ) {baseJ = BaseJ;}
   void GetMassPropertiesReport(void) const;
   
diff --git a/src/FDM/JSBSim/models/FGModel.cpp b/src/FDM/JSBSim/models/FGModel.cpp
index fe8039919..71f6cb3ed 100644
--- a/src/FDM/JSBSim/models/FGModel.cpp
+++ b/src/FDM/JSBSim/models/FGModel.cpp
@@ -57,7 +57,7 @@ using namespace std;
 
 namespace JSBSim {
 
-static const char *IdSrc = "$Id: FGModel.cpp,v 1.15 2010/09/07 00:19:38 jberndt Exp $";
+static const char *IdSrc = "$Id: FGModel.cpp,v 1.16 2010/11/18 12:38:06 jberndt Exp $";
 static const char *IdHdr = ID_MODEL;
 
 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@@ -72,18 +72,6 @@ FGModel::FGModel(FGFDMExec* fdmex)
 {
   FDMExec     = fdmex;
 
-  Atmosphere      = 0;
-  FCS             = 0;
-  Propulsion      = 0;
-  MassBalance     = 0;
-  Aerodynamics    = 0;
-  Inertial        = 0;
-  GroundReactions = 0;
-  ExternalReactions = 0;
-  Aircraft        = 0;
-  Propagate       = 0;
-  Auxiliary       = 0;
-
   //in order for FGModel derived classes to self-bind (that is, call
   //their bind function in the constructor, the PropertyManager pointer
   //must be brought up now.
@@ -106,31 +94,7 @@ FGModel::~FGModel()
 
 bool FGModel::InitModel(void)
 {
-  Atmosphere      = FDMExec->GetAtmosphere();
-  FCS             = FDMExec->GetFCS();
-  Propulsion      = FDMExec->GetPropulsion();
-  MassBalance     = FDMExec->GetMassBalance();
-  Aerodynamics    = FDMExec->GetAerodynamics();
-  Inertial        = FDMExec->GetInertial();
-  GroundReactions = FDMExec->GetGroundReactions();
-  ExternalReactions = FDMExec->GetExternalReactions();
-  BuoyantForces   = FDMExec->GetBuoyantForces();
-  Aircraft        = FDMExec->GetAircraft();
-  Propagate       = FDMExec->GetPropagate();
-  Auxiliary       = FDMExec->GetAuxiliary();
-
-  if (!Atmosphere ||
-      !FCS ||
-      !Propulsion ||
-      !MassBalance ||
-      !Aerodynamics ||
-      !Inertial ||
-      !GroundReactions ||
-      !ExternalReactions ||
-      !Aircraft ||
-      !Propagate ||
-      !Auxiliary) return(false);
-  else return(true);
+  return true;
 }
 
 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
diff --git a/src/FDM/JSBSim/models/FGModel.h b/src/FDM/JSBSim/models/FGModel.h
index 775ea9f29..470dc731a 100644
--- a/src/FDM/JSBSim/models/FGModel.h
+++ b/src/FDM/JSBSim/models/FGModel.h
@@ -48,7 +48,7 @@ INCLUDES
 DEFINITIONS
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
 
-#define ID_MODEL "$Id: FGModel.h,v 1.16 2010/09/22 11:33:40 jberndt Exp $"
+#define ID_MODEL "$Id: FGModel.h,v 1.18 2010/11/18 12:38:06 jberndt Exp $"
 
 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 FORWARD DECLARATIONS
@@ -57,18 +57,6 @@ FORWARD DECLARATIONS
 namespace JSBSim {
 
 class FGFDMExec;
-class FGAtmosphere;
-class FGFCS;
-class FGPropulsion;
-class FGMassBalance;
-class FGAerodynamics;
-class FGInertial;
-class FGGroundReactions;
-class FGExternalReactions;
-class FGBuoyantForces;
-class FGAircraft;
-class FGPropagate;
-class FGAuxiliary;
 class Element;
 class FGPropertyManager;
 
@@ -118,18 +106,6 @@ protected:
   virtual void Debug(int from);
 
   FGFDMExec*         FDMExec;
-  FGAtmosphere*      Atmosphere;
-  FGFCS*             FCS;
-  FGPropulsion*      Propulsion;
-  FGMassBalance*     MassBalance;
-  FGAerodynamics*    Aerodynamics;
-  FGInertial*        Inertial;
-  FGGroundReactions* GroundReactions;
-  FGExternalReactions* ExternalReactions;
-  FGBuoyantForces*   BuoyantForces;
-  FGAircraft*        Aircraft;
-  FGPropagate*       Propagate;
-  FGAuxiliary*       Auxiliary;
   FGPropertyManager* PropertyManager;
 };
 }
diff --git a/src/FDM/JSBSim/models/FGOutput.cpp b/src/FDM/JSBSim/models/FGOutput.cpp
index c074d9813..3e5c986c6 100644
--- a/src/FDM/JSBSim/models/FGOutput.cpp
+++ b/src/FDM/JSBSim/models/FGOutput.cpp
@@ -74,7 +74,7 @@ using namespace std;
 
 namespace JSBSim {
 
-static const char *IdSrc = "$Id: FGOutput.cpp,v 1.49 2010/10/15 11:30:29 jberndt Exp $";
+static const char *IdSrc = "$Id: FGOutput.cpp,v 1.50 2010/11/18 12:38:06 jberndt Exp $";
 static const char *IdHdr = ID_OUTPUT;
 
 // (stolen from FGFS native_fdm.cxx)
@@ -237,6 +237,19 @@ void FGOutput::SetProtocol(const string& protocol)
 
 void FGOutput::DelimitedOutput(const string& fname)
 {
+  const FGAerodynamics* Aerodynamics = FDMExec->GetAerodynamics();
+  const FGAuxiliary* Auxiliary = FDMExec->GetAuxiliary();
+  const FGAircraft* Aircraft = FDMExec->GetAircraft();
+  const FGAtmosphere* Atmosphere = FDMExec->GetAtmosphere();
+  const FGPropulsion* Propulsion = FDMExec->GetPropulsion();
+  const FGMassBalance* MassBalance = FDMExec->GetMassBalance();
+  const FGPropagate* Propagate = FDMExec->GetPropagate();
+  const FGFCS* FCS = FDMExec->GetFCS();
+  const FGInertial* Inertial = FDMExec->GetInertial();
+  const FGGroundReactions* GroundReactions = FDMExec->GetGroundReactions();
+  const FGExternalReactions* ExternalReactions = FDMExec->GetExternalReactions();
+  const FGBuoyantForces* BuoyantForces = FDMExec->GetBuoyantForces();
+
   streambuf* buffer;
   string scratch = "";
 
@@ -493,6 +506,13 @@ void FGOutput::DelimitedOutput(const string& fname)
 
 void FGOutput::SocketDataFill(FGNetFDM* net)
 {
+  const FGAerodynamics* Aerodynamics = FDMExec->GetAerodynamics();
+  const FGAuxiliary* Auxiliary = FDMExec->GetAuxiliary();
+  const FGPropulsion* Propulsion = FDMExec->GetPropulsion();
+  const FGMassBalance* MassBalance = FDMExec->GetMassBalance();
+  const FGPropagate* Propagate = FDMExec->GetPropagate();
+  const FGFCS* FCS = FDMExec->GetFCS();
+  const FGGroundReactions* GroundReactions = FDMExec->GetGroundReactions();
     unsigned int i;
 
     // Version
@@ -701,6 +721,16 @@ void FGOutput::FlightGearSocketOutput(void)
 
 void FGOutput::SocketOutput(void)
 {
+  const FGAerodynamics* Aerodynamics = FDMExec->GetAerodynamics();
+  const FGAuxiliary* Auxiliary = FDMExec->GetAuxiliary();
+  const FGPropulsion* Propulsion = FDMExec->GetPropulsion();
+  const FGMassBalance* MassBalance = FDMExec->GetMassBalance();
+  const FGPropagate* Propagate = FDMExec->GetPropagate();
+  const FGFCS* FCS = FDMExec->GetFCS();
+  const FGAtmosphere* Atmosphere = FDMExec->GetAtmosphere();
+  const FGAircraft* Aircraft = FDMExec->GetAircraft();
+  const FGGroundReactions* GroundReactions = FDMExec->GetGroundReactions();
+
   string asciiData, scratch;
 
   if (socket == NULL) return;
diff --git a/src/FDM/JSBSim/models/FGOutput.h b/src/FDM/JSBSim/models/FGOutput.h
index c4ef388d5..d03ac5981 100644
--- a/src/FDM/JSBSim/models/FGOutput.h
+++ b/src/FDM/JSBSim/models/FGOutput.h
@@ -51,7 +51,7 @@ INCLUDES
 DEFINITIONS
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
 
-#define ID_OUTPUT "$Id: FGOutput.h,v 1.18 2010/10/15 11:30:29 jberndt Exp $"
+#define ID_OUTPUT "$Id: FGOutput.h,v 1.19 2010/10/31 04:48:46 jberndt Exp $"
 
 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 FORWARD DECLARATIONS
@@ -124,7 +124,7 @@ CLASS DOCUMENTATION
     propulsion       ON|OFF
 </pre>
     NOTE that Time is always output with the data.
-    @version $Id: FGOutput.h,v 1.18 2010/10/15 11:30:29 jberndt Exp $
+    @version $Id: FGOutput.h,v 1.19 2010/10/31 04:48:46 jberndt Exp $
  */
 
 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@@ -178,7 +178,6 @@ public:
     /** Subsystem: Propulsion (= 4096)       */ ssPropulsion      = 4096
   } subsystems;
 
-
   FGNetFDM fgSockBuf;
 
 private:
diff --git a/src/FDM/JSBSim/models/FGPropagate.cpp b/src/FDM/JSBSim/models/FGPropagate.cpp
index 0fec89b0c..066010405 100644
--- a/src/FDM/JSBSim/models/FGPropagate.cpp
+++ b/src/FDM/JSBSim/models/FGPropagate.cpp
@@ -71,7 +71,7 @@ using namespace std;
 
 namespace JSBSim {
 
-static const char *IdSrc = "$Id: FGPropagate.cpp,v 1.71 2010/10/15 11:34:09 jberndt Exp $";
+static const char *IdSrc = "$Id: FGPropagate.cpp,v 1.73 2010/11/18 12:38:06 jberndt Exp $";
 static const char *IdHdr = ID_PROPAGATE;
 
 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@@ -94,7 +94,6 @@ FGPropagate::FGPropagate(FGFDMExec* fdmex) : FGModel(fdmex)
   integrator_rotational_position = eAdamsBashforth2;
   integrator_translational_position = eTrapezoidal;
 
-  VState.dqPQRdot.resize(4, FGColumnVector3(0.0,0.0,0.0));
   VState.dqPQRidot.resize(4, FGColumnVector3(0.0,0.0,0.0));
   VState.dqUVWidot.resize(4, FGColumnVector3(0.0,0.0,0.0));
   VState.dqInertialVelocity.resize(4, FGColumnVector3(0.0,0.0,0.0));
@@ -118,18 +117,17 @@ bool FGPropagate::InitModel(void)
   if (!FGModel::InitModel()) return false;
 
   // For initialization ONLY:
-  SeaLevelRadius = LocalTerrainRadius = Inertial->GetRefRadius();
+  SeaLevelRadius = LocalTerrainRadius = FDMExec->GetInertial()->GetRefRadius();
 
   VState.vLocation.SetRadius( LocalTerrainRadius + 4.0 );
-  VState.vLocation.SetEllipse(Inertial->GetSemimajor(), Inertial->GetSemiminor());
-  vOmegaEarth = FGColumnVector3( 0.0, 0.0, Inertial->omega() ); // Earth rotation vector
+  VState.vLocation.SetEllipse(FDMExec->GetInertial()->GetSemimajor(), FDMExec->GetInertial()->GetSemiminor());
+  vOmegaEarth = FGColumnVector3( 0.0, 0.0, FDMExec->GetInertial()->omega() ); // Earth rotation vector
 
   vPQRdot.InitMatrix();
   vQtrndot = FGQuaternion(0,0,0);
   vUVWdot.InitMatrix();
   vInertialVelocity.InitMatrix();
 
-  VState.dqPQRdot.resize(4, FGColumnVector3(0.0,0.0,0.0));
   VState.dqPQRidot.resize(4, FGColumnVector3(0.0,0.0,0.0));
   VState.dqUVWidot.resize(4, FGColumnVector3(0.0,0.0,0.0));
   VState.dqInertialVelocity.resize(4, FGColumnVector3(0.0,0.0,0.0));
@@ -157,7 +155,7 @@ void FGPropagate::SetInitialState(const FGInitialCondition *FGIC)
                                 FGIC->GetLatitudeRadIC(),
                                 FGIC->GetAltitudeASLFtIC() + FGIC->GetSeaLevelRadiusFtIC() );
 
-  VState.vLocation.SetEarthPositionAngle(Inertial->GetEarthPositionAngle());
+  VState.vLocation.SetEarthPositionAngle(FDMExec->GetInertial()->GetEarthPositionAngle());
 
   Ti2ec = GetTi2ec();         // ECI to ECEF transform
   Tec2i = Ti2ec.Transposed(); // ECEF to ECI frame transform
@@ -259,7 +257,7 @@ bool FGPropagate::Run(void)
   // matrices that are consistent with the new state of the vehicle
 
   // 1. Update the Earth position angle (EPA)
-  VState.vLocation.SetEarthPositionAngle(Inertial->GetEarthPositionAngle());
+  VState.vLocation.SetEarthPositionAngle(FDMExec->GetInertial()->GetEarthPositionAngle());
 
   // 2. Update the Ti2ec and Tec2i transforms from the updated EPA
   Ti2ec = GetTi2ec();          // ECI to ECEF transform
@@ -314,9 +312,9 @@ bool FGPropagate::Run(void)
 
 void FGPropagate::CalculatePQRdot(void)
 {
-  const FGColumnVector3& vMoments = Aircraft->GetMoments(); // current moments
-  const FGMatrix33& J = MassBalance->GetJ();                // inertia matrix
-  const FGMatrix33& Jinv = MassBalance->GetJinv();          // inertia matrix inverse
+  const FGColumnVector3& vMoments = FDMExec->GetAircraft()->GetMoments(); // current moments
+  const FGMatrix33& J = FDMExec->GetMassBalance()->GetJ();                // inertia matrix
+  const FGMatrix33& Jinv = FDMExec->GetMassBalance()->GetJinv();          // inertia matrix inverse
 
   // Compute body frame rotational accelerations based on the current body
   // moments and the total inertial angular velocity expressed in the body
@@ -358,8 +356,8 @@ void FGPropagate::CalculateQuatdot(void)
 
 void FGPropagate::CalculateUVWdot(void)
 {
-  double mass = MassBalance->GetMass();                      // mass
-  const FGColumnVector3& vForces = Aircraft->GetForces();    // current forces
+  double mass = FDMExec->GetMassBalance()->GetMass();                      // mass
+  const FGColumnVector3& vForces = FDMExec->GetAircraft()->GetForces();    // current forces
 
   vUVWdot = vForces/mass - (VState.vPQR + 2.0*(Ti2b *vOmegaEarth)) * VState.vUVW;
 
@@ -369,10 +367,10 @@ void FGPropagate::CalculateUVWdot(void)
   // Include Gravitation accel
   switch (gravType) {
     case gtStandard:
-      vGravAccel = Tl2b * FGColumnVector3( 0.0, 0.0, Inertial->GetGAccel(VehicleRadius) );
+      vGravAccel = Tl2b * FGColumnVector3( 0.0, 0.0, FDMExec->GetInertial()->GetGAccel(VehicleRadius) );
       break;
     case gtWGS84:
-      vGravAccel = Tec2b * Inertial->GetGravityJ2(VState.vLocation);
+      vGravAccel = Tec2b * FDMExec->GetInertial()->GetGravityJ2(VState.vLocation);
       break;
   }
 
@@ -471,15 +469,15 @@ void FGPropagate::Integrate( FGQuaternion& Integrand,
 
 void FGPropagate::ResolveFrictionForces(double dt)
 {
-  const double invMass = 1.0 / MassBalance->GetMass();
-  const FGMatrix33& Jinv = MassBalance->GetJinv();
+  const double invMass = 1.0 / FDMExec->GetMassBalance()->GetMass();
+  const FGMatrix33& Jinv = FDMExec->GetMassBalance()->GetJinv();
   vector <FGColumnVector3> JacF, JacM;
   FGColumnVector3 vdot, wdot;
   FGColumnVector3 Fc, Mc;
   int n = 0, i;
 
   // Compiles data from the ground reactions to build up the jacobian matrix
-  for (MultiplierIterator it=MultiplierIterator(GroundReactions); *it; ++it, n++) {
+  for (MultiplierIterator it=MultiplierIterator(FDMExec->GetGroundReactions()); *it; ++it, n++) {
     JacF.push_back((*it)->ForceJacobian);
     JacM.push_back((*it)->MomentJacobian);
   }
@@ -495,7 +493,7 @@ void FGPropagate::ResolveFrictionForces(double dt)
 
   // Initializes the Lagrange multipliers
   i = 0;
-  for (MultiplierIterator it=MultiplierIterator(GroundReactions); *it; ++it, i++) {
+  for (MultiplierIterator it=MultiplierIterator(FDMExec->GetGroundReactions()); *it; ++it, i++) {
     lambda[i] = (*it)->value;
     lambdaMax[i] = (*it)->Max;
     lambdaMin[i] = (*it)->Min;
@@ -568,10 +566,10 @@ void FGPropagate::ResolveFrictionForces(double dt)
   // Save the value of the Lagrange multipliers to accelerate the convergence
   // of the Gauss-Seidel algorithm at next iteration.
   i = 0;
-  for (MultiplierIterator it=MultiplierIterator(GroundReactions); *it; ++it)
+  for (MultiplierIterator it=MultiplierIterator(FDMExec->GetGroundReactions()); *it; ++it)
     (*it)->value = lambda[i++];
 
-  GroundReactions->UpdateForcesAndMoments();
+  FDMExec->GetGroundReactions()->UpdateForcesAndMoments();
 }
 
 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@@ -633,13 +631,11 @@ void FGPropagate::InitializeDerivatives(void)
   CalculateInertialVelocity(); // Translational position derivative
 
   // Initialize past values deques
-  VState.dqPQRdot.clear();
   VState.dqPQRidot.clear();
   VState.dqUVWidot.clear();
   VState.dqInertialVelocity.clear();
   VState.dqQtrndot.clear();
   for (int i=0; i<4; i++) {
-    VState.dqPQRdot.push_front(vPQRdot);
     VState.dqPQRidot.push_front(vPQRidot);
     VState.dqUVWidot.push_front(vUVWdot);
     VState.dqInertialVelocity.push_front(VState.vInertialVelocity);
@@ -861,7 +857,7 @@ void FGPropagate::Debug(int from)
          << reset << endl;
     cout << endl;
     cout << highint << "  Earth Position Angle (deg): " << setw(8) << setprecision(3) << reset
-                    << Inertial->GetEarthPositionAngleDeg() << endl;
+                    << FDMExec->GetInertial()->GetEarthPositionAngleDeg() << endl;
     cout << endl;
     cout << highint << "  Body velocity (ft/sec): " << setw(8) << setprecision(3) << reset << VState.vUVW << endl;
     cout << highint << "  Local velocity (ft/sec): " << setw(8) << setprecision(3) << reset << vVel << endl;
diff --git a/src/FDM/JSBSim/models/FGPropagate.h b/src/FDM/JSBSim/models/FGPropagate.h
index 86e5cd6a0..1c8d70cb5 100644
--- a/src/FDM/JSBSim/models/FGPropagate.h
+++ b/src/FDM/JSBSim/models/FGPropagate.h
@@ -49,7 +49,7 @@ INCLUDES
 DEFINITIONS
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
 
-#define ID_PROPAGATE "$Id: FGPropagate.h,v 1.51 2010/10/07 03:45:40 jberndt Exp $"
+#define ID_PROPAGATE "$Id: FGPropagate.h,v 1.52 2010/10/31 04:48:46 jberndt Exp $"
 
 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 FORWARD DECLARATIONS
@@ -102,7 +102,7 @@ CLASS DOCUMENTATION
     @endcode
 
     @author Jon S. Berndt, Mathias Froehlich
-    @version $Id: FGPropagate.h,v 1.51 2010/10/07 03:45:40 jberndt Exp $
+    @version $Id: FGPropagate.h,v 1.52 2010/10/31 04:48:46 jberndt Exp $
   */
 
 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@@ -152,7 +152,6 @@ public:
 
     FGColumnVector3 vInertialPosition;
 
-    deque <FGColumnVector3> dqPQRdot;
     deque <FGColumnVector3> dqPQRidot;
     deque <FGColumnVector3> dqUVWidot;
     deque <FGColumnVector3> dqInertialVelocity;
diff --git a/src/FDM/JSBSim/models/FGPropulsion.cpp b/src/FDM/JSBSim/models/FGPropulsion.cpp
index 21f469c1f..32d8b42a1 100644
--- a/src/FDM/JSBSim/models/FGPropulsion.cpp
+++ b/src/FDM/JSBSim/models/FGPropulsion.cpp
@@ -65,7 +65,7 @@ using namespace std;
 
 namespace JSBSim {
 
-static const char *IdSrc = "$Id: FGPropulsion.cpp,v 1.41 2010/10/15 11:32:41 jberndt Exp $";
+static const char *IdSrc = "$Id: FGPropulsion.cpp,v 1.43 2010/11/18 12:38:06 jberndt Exp $";
 static const char *IdHdr = ID_PROPULSION;
 
 extern short debug_lvl;
@@ -115,6 +115,8 @@ FGPropulsion::~FGPropulsion()
 
 bool FGPropulsion::InitModel(void)
 {
+  bool result = true;
+
   if (!FGModel::InitModel()) return false;
 
   for (unsigned int i=0; i<numTanks; i++) Tanks[i]->ResetToIC();
@@ -123,18 +125,28 @@ bool FGPropulsion::InitModel(void)
     switch (Engines[i]->GetType()) {
       case FGEngine::etPiston:
         ((FGPiston*)Engines[i])->ResetToIC();
-        if (HasInitializedEngines && (InitializedEngines & i)) InitRunning(i);
+        try {
+          if (HasInitializedEngines && (InitializedEngines & i)) InitRunning(i);
+        } catch (string str) {
+          cerr << str << endl;
+          result = false;
+        }
         break;
       case FGEngine::etTurbine:
         ((FGTurbine*)Engines[i])->ResetToIC();
-        if (HasInitializedEngines && (InitializedEngines & i)) InitRunning(i);
+        try {
+          if (HasInitializedEngines && (InitializedEngines & i)) InitRunning(i);
+        } catch (string str) {
+          cerr << str << endl;
+          result = false;
+        }
         break;
       default:
         break;
     }
   }
 
-  return true;
+  return result;
 }
 
 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@@ -226,14 +238,13 @@ bool FGPropulsion::GetSteadyState(void)
 
 void FGPropulsion::InitRunning(int n)
 {
-  if (n > 0) { // A specific engine is supposed to be initialized
+  if (n >= 0) { // A specific engine is supposed to be initialized
 
     if (n >= (int)GetNumEngines() ) {
-      cerr << "Tried to initialize a non-existent engine!" << endl;
-      throw;
+      throw(string("Tried to initialize a non-existent engine!"));
     }
-    FCS->SetThrottleCmd(n,1);
-    FCS->SetMixtureCmd(n,1);
+    FDMExec->GetFCS()->SetThrottleCmd(n,1);
+    FDMExec->GetFCS()->SetMixtureCmd(n,1);
     GetEngine(n)->InitRunning();
     GetSteadyState();
 
@@ -243,16 +254,14 @@ void FGPropulsion::InitRunning(int n)
   } else if (n < 0) { // -1 refers to "All Engines"
 
     for (unsigned int i=0; i<GetNumEngines(); i++) {
-      FCS->SetThrottleCmd(i,1);
-      FCS->SetMixtureCmd(i,1);
+      FDMExec->GetFCS()->SetThrottleCmd(i,1);
+      FDMExec->GetFCS()->SetMixtureCmd(i,1);
       GetEngine(i)->InitRunning();
     }
     GetSteadyState();
     InitializedEngines = -1;
     HasInitializedEngines = true;
 
-  } else if (n == 0) { // No engines are to be initialized
-    // Do nothing
   }
 }
 
@@ -325,7 +334,7 @@ bool FGPropulsion::Load(Element* el)
       return false;
     }
 
-    FCS->AddThrottle();
+    FDMExec->GetFCS()->AddThrottle();
     ThrottleAdded = true;
 
     numEngines++;
@@ -335,7 +344,7 @@ bool FGPropulsion::Load(Element* el)
   }
 
   CalculateTankInertias();
-  if (!ThrottleAdded) FCS->AddThrottle(); // need to have at least one throttle
+  if (!ThrottleAdded) FDMExec->GetFCS()->AddThrottle(); // need to have at least one throttle
 
   // Process fuel dump rate
   if (el->FindElement("dump-rate"))
@@ -401,7 +410,7 @@ ifstream* FGPropulsion::FindEngineFile(const string& engine_filename)
 
 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
-string FGPropulsion::GetPropulsionStrings(const string& delimiter)
+string FGPropulsion::GetPropulsionStrings(const string& delimiter) const
 {
   unsigned int i;
 
@@ -425,7 +434,7 @@ string FGPropulsion::GetPropulsionStrings(const string& delimiter)
 
 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
-string FGPropulsion::GetPropulsionValues(const string& delimiter)
+string FGPropulsion::GetPropulsionValues(const string& delimiter) const
 {
   unsigned int i;
 
@@ -483,7 +492,7 @@ FGMatrix33& FGPropulsion::CalculateTankInertias(void)
   tankJ = FGMatrix33();
 
   for (unsigned int i=0; i<size; i++) {
-    tankJ += MassBalance->GetPointmassInertia( lbtoslug * Tanks[i]->GetContents(),
+    tankJ += FDMExec->GetMassBalance()->GetPointmassInertia( lbtoslug * Tanks[i]->GetContents(),
                                                Tanks[i]->GetXYZ() );
     tankJ(1,1) += Tanks[i]->GetIxx();
     tankJ(2,2) += Tanks[i]->GetIyy();
diff --git a/src/FDM/JSBSim/models/FGPropulsion.h b/src/FDM/JSBSim/models/FGPropulsion.h
index ff3502c95..50dd860cd 100644
--- a/src/FDM/JSBSim/models/FGPropulsion.h
+++ b/src/FDM/JSBSim/models/FGPropulsion.h
@@ -49,7 +49,7 @@ INCLUDES
 DEFINITIONS
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
 
-#define ID_PROPULSION "$Id: FGPropulsion.h,v 1.25 2010/01/02 17:58:01 andgi Exp $"
+#define ID_PROPULSION "$Id: FGPropulsion.h,v 1.26 2010/11/18 12:38:06 jberndt Exp $"
 
 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 FORWARD DECLARATIONS
@@ -91,7 +91,7 @@ CLASS DOCUMENTATION
   @endcode
 
     @author Jon S. Berndt
-    @version $Id: FGPropulsion.h,v 1.25 2010/01/02 17:58:01 andgi Exp $
+    @version $Id: FGPropulsion.h,v 1.26 2010/11/18 12:38:06 jberndt Exp $
     @see
     FGEngine
     FGTank
@@ -125,32 +125,32 @@ public:
   bool Load(Element* el);
 
   /// Retrieves the number of engines defined for the aircraft.
-  inline unsigned int GetNumEngines(void) const {return (unsigned int)Engines.size();}
+  unsigned int GetNumEngines(void) const {return (unsigned int)Engines.size();}
 
   /** Retrieves an engine object pointer from the list of engines.
       @param index the engine index within the vector container
       @return the address of the specific engine, or zero if no such engine is
               available */
-  inline FGEngine* GetEngine(unsigned int index) {
+  FGEngine* GetEngine(unsigned int index) const {
                       if (index < Engines.size()) return Engines[index];
                       else                        return 0L;      }
 
   /// Retrieves the number of tanks defined for the aircraft.
-  inline unsigned int GetNumTanks(void) const {return (unsigned int)Tanks.size();}
+  unsigned int GetNumTanks(void) const {return (unsigned int)Tanks.size();}
 
   /** Retrieves a tank object pointer from the list of tanks.
       @param index the tank index within the vector container
       @return the address of the specific tank, or zero if no such tank is
               available */
-  inline FGTank* GetTank(unsigned int index) {
+  FGTank* GetTank(unsigned int index) const {
                       if (index < Tanks.size()) return Tanks[index];
                       else                      return 0L;        }
 
   /** Returns the number of fuel tanks currently actively supplying fuel */
-  inline int GetnumSelectedFuelTanks(void) const {return numSelectedFuelTanks;}
+  int GetnumSelectedFuelTanks(void) const {return numSelectedFuelTanks;}
 
   /** Returns the number of oxidizer tanks currently actively supplying oxidizer */
-  inline int GetnumSelectedOxiTanks(void) const {return numSelectedOxiTanks;}
+  int GetnumSelectedOxiTanks(void) const {return numSelectedOxiTanks;}
 
   /** Loops the engines until thrust output steady (used for trimming) */
   bool GetSteadyState(void);
@@ -158,18 +158,18 @@ public:
   /** Sets up the engines as running */
   void InitRunning(int n);
 
-  std::string GetPropulsionStrings(const std::string& delimiter);
-  std::string GetPropulsionValues(const std::string& delimiter);
+  std::string GetPropulsionStrings(const std::string& delimiter) const;
+  std::string GetPropulsionValues(const std::string& delimiter) const;
 
-  inline FGColumnVector3& GetForces(void)  {return vForces; }
-  inline double GetForces(int n) const { return vForces(n);}
-  inline FGColumnVector3& GetMoments(void) {return vMoments;}
-  inline double GetMoments(int n) const {return vMoments(n);}
+  const FGColumnVector3& GetForces(void) const {return vForces; }
+  double GetForces(int n) const { return vForces(n);}
+  const FGColumnVector3& GetMoments(void) const {return vMoments;}
+  double GetMoments(int n) const {return vMoments(n);}
 
-  inline bool GetRefuel(void) const {return refuel;}
-  inline void SetRefuel(bool setting) {refuel = setting;}
-  inline bool GetFuelDump(void) const {return dump;}
-  inline void SetFuelDump(bool setting) {dump = setting;}
+  bool GetRefuel(void) const {return refuel;}
+  void SetRefuel(bool setting) {refuel = setting;}
+  bool GetFuelDump(void) const {return dump;}
+  void SetFuelDump(bool setting) {dump = setting;}
   double Transfer(int source, int target, double amount);
   void DoRefuel(double time_slice);
   void DumpFuel(double time_slice);
diff --git a/src/FDM/JSBSim/models/atmosphere/FGMSIS.cpp b/src/FDM/JSBSim/models/atmosphere/FGMSIS.cpp
index 390a11449..0afaa831a 100755
--- a/src/FDM/JSBSim/models/atmosphere/FGMSIS.cpp
+++ b/src/FDM/JSBSim/models/atmosphere/FGMSIS.cpp
@@ -66,7 +66,7 @@ using namespace std;
 
 namespace JSBSim {
 
-static const char *IdSrc = "$Id: FGMSIS.cpp,v 1.13 2010/02/25 05:21:36 jberndt Exp $";
+static const char *IdSrc = "$Id: FGMSIS.cpp,v 1.14 2010/11/18 12:38:06 jberndt Exp $";
 static const char *IdHdr = ID_MSIS;
 
 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@@ -153,11 +153,11 @@ bool MSIS::Run(void)
   //do temp, pressure, and density first
   if (!useExternal) {
     // get sea-level values
-    Calculate(Auxiliary->GetDayOfYear(),
-              Auxiliary->GetSecondsInDay(),
+    Calculate(FDMExec->GetAuxiliary()->GetDayOfYear(),
+              FDMExec->GetAuxiliary()->GetSecondsInDay(),
               0.0,
-              Propagate->GetLocation().GetLatitudeDeg(),
-              Propagate->GetLocation().GetLongitudeDeg());
+              FDMExec->GetPropagate()->GetLocation().GetLatitudeDeg(),
+              FDMExec->GetPropagate()->GetLocation().GetLongitudeDeg());
     SLtemperature = output.t[1] * 1.8;
     SLdensity     = output.d[5] * 1.940321;
     SLpressure    = 1716.488 * SLdensity * SLtemperature;
@@ -168,11 +168,11 @@ bool MSIS::Run(void)
     rSLsoundspeed  = 1.0/SLsoundspeed;
 
     // get at-altitude values
-    Calculate(Auxiliary->GetDayOfYear(),
-              Auxiliary->GetSecondsInDay(),
-              Propagate->GetAltitudeASL(),
-              Propagate->GetLocation().GetLatitudeDeg(),
-              Propagate->GetLocation().GetLongitudeDeg());
+    Calculate(FDMExec->GetAuxiliary()->GetDayOfYear(),
+              FDMExec->GetAuxiliary()->GetSecondsInDay(),
+              FDMExec->GetPropagate()->GetAltitudeASL(),
+              FDMExec->GetPropagate()->GetLocation().GetLatitudeDeg(),
+              FDMExec->GetPropagate()->GetLocation().GetLongitudeDeg());
     intTemperature = output.t[1] * 1.8;
     intDensity     = output.d[5] * 1.940321;
     intPressure    = 1716.488 * intDensity * intTemperature;