diff --git a/sw/simulator/nps_fdm.h b/sw/simulator/nps_fdm.h
index bbf8d08cae..de0a5ea0f2 100644
--- a/sw/simulator/nps_fdm.h
+++ b/sw/simulator/nps_fdm.h
@@ -22,7 +22,7 @@ struct NpsFdm {
 
 extern struct NpsFdm fdm;
 
-extern void nps_fdm_init();
-extern void nps_fdm_run_step(double* commands, double dt);
+extern void nps_fdm_init(double dt);
+extern void nps_fdm_run_step(double* commands);
 
 #endif /* NPS_FDM */
diff --git a/sw/simulator/nps_fdm_jsbsim.c b/sw/simulator/nps_fdm_jsbsim.c
new file mode 100644
index 0000000000..4ff95894a3
--- /dev/null
+++ b/sw/simulator/nps_fdm_jsbsim.c
@@ -0,0 +1,46 @@
+
+#include <FGFDMExec.h>
+#include <FGJSBBase.h>
+#include <FGState.h>
+
+#include "nps_fdm.h"
+
+#include "airframe.h"
+
+using namespace JSBSim;
+
+void nps_fdm_feed_jsbsim(void);
+void nps_fdm_fetch_state(void);
+
+FGFDMExec* FDMExec;
+
+void nps_fdm_init(double dt) {
+
+  // FDMExec = new FGFDMExec();
+
+}
+
+void nps_fdm_run_step(double* commands) {
+
+  nps_fdm_feed_jsbsim(double* commands);
+
+  /* run JSBSim */
+
+  nps_fdm_fetch_state();
+
+}
+
+void nps_fdm_feed_jsbsim(double* commands) {
+
+#if 0
+  printf("Actuators Names:\n");
+  for (int i=0; i<SERVOS_NB; i++) {
+    printf("%s\n", ACTUATOR_COMMAND_NAMES[i]);
+  }
+#endif
+
+void nps_fdm_fetch_state(void) {
+
+  /* JSBSim to fdm */
+
+}