diff --git a/configure.in b/configure.in
index c6028049e6b0031aa3940bbca49ba82b4211ae02..f0d87d9baa0769a808c572eb234bacc211ccd889 100644
--- a/configure.in
+++ b/configure.in
@@ -1,10 +1,10 @@
 dnl Process this file with autoconf to produce a configure script.
-AC_INIT(JSBSim.cpp, 1.0.rc3-advtrim-2, jon@jsbsim.org)
+AC_INIT(JSBSim.cpp, 1.0.rc3-advtrim-4, jon@jsbsim.org)
 
 dnl set the $host variable based on local machine/os
 AC_CANONICAL_TARGET
 
-AM_INIT_AUTOMAKE(jsbsim, 1.0.rc3-advtrim-2)
+AM_INIT_AUTOMAKE(jsbsim, 1.0.rc3-advtrim-4)
 AC_CONFIG_MACRO_DIR([m4])
 
 # Before making a release, the LT_VERSION string should be modified.
diff --git a/src/math/FGStateSpace.h b/src/math/FGStateSpace.h
index ea30f8f6fe49dca906245c486f1314c558695435..ce57c458ed0f9da6a1a1c89e9d3f4d93d0c99e51 100644
--- a/src/math/FGStateSpace.h
+++ b/src/math/FGStateSpace.h
@@ -256,6 +256,62 @@ public:
 
     };
 
+  	class VGround : public Component
+    {
+    public:
+        VGround() : Component("VGround","ft/s") {};
+        double get() const
+        {
+            return m_fdm->GetAuxiliary()->GetVground();
+        }
+        void set(double val)
+        {
+			m_fdm->GetIC()->SetVgroundFpsIC(val);
+        }
+    };
+
+	class AccelX : public Component
+    {
+    public:
+        AccelX() : Component("AccelX","ft/s^2") {};
+        double get() const
+        {
+            return m_fdm->GetAuxiliary()->GetPilotAccel(1);
+        }
+        void set(double val)
+        {
+			// XXX: not possible to implement currently
+        }
+    };
+
+	class AccelY : public Component
+    {
+    public:
+        AccelY() : Component("AccelY","ft/s^2") {};
+        double get() const
+        {
+            return m_fdm->GetAuxiliary()->GetPilotAccel(2);
+        }
+        void set(double val)
+        {
+			// XXX: not possible to implement currently
+        }
+    };
+
+	class AccelZ : public Component
+    {
+    public:
+        AccelZ() : Component("AccelZ","ft/s^2") {};
+        double get() const
+        {
+            return m_fdm->GetAuxiliary()->GetPilotAccel(3);
+        }
+        void set(double val)
+        {
+			// XXX: not possible to implement currently
+        }
+    };
+
     class Alpha : public Component
     {
     public: