diff --git a/Makefile b/Makefile
index 4c6e6f9a90..42b3c57edf 100644
--- a/Makefile
+++ b/Makefile
@@ -113,6 +113,16 @@ include Makefile.ac
 sim : sim_static
 ac_h ac1 ac2 ac3 ac fbw ap: static conf
 
+###
+#
+# temporary hack for quadrotor simulator
+#
+booz_sim:
+	make AIRCRAFT=BOOZ flt.compile
+	make AIRCRAFT=BOOZ ctl.compile
+	cd sw/simulator; make clean booz_sim
+
+
 ##### preliminary hard wired arm7 bootloader rules
 #
 #
diff --git a/conf/Makefile.sim b/conf/Makefile.sim
index 0f123aa8d7..6a38715c70 100644
--- a/conf/Makefile.sim
+++ b/conf/Makefile.sim
@@ -22,9 +22,14 @@
 # 
 
 
+ifeq ($(SIM_TYPE),BOOZ)
+sim.CFLAGS +=  `pkg-config glib-2.0 --cflags` -I /usr/include/meschach
+sim.LDFLAGS += `pkg-config glib-2.0 --libs` -lm -lmeschach -lpcre -lglibivy
+endif
+
+
 #
-# This is the common Makefile for the avr-target.
-# Edit the configuration part to suit your local install
+# This is the common Makefile for the sim target.
 #
 
 SRC_ARCH = $(PAPARAZZI_SRC)/sw/airborne/sim
@@ -48,13 +53,21 @@ INCLUDES += -I `ocamlc -where`
 CFLAGS		=						\
 	-W -Wall 						\
 	$(INCLUDES)					  	\
-	-Wstrict-prototypes					\
 	$($(TARGET).CFLAGS)					\
 	$(LOCAL_CFLAGS)						\
 	-O2							\
 
+# meschach prototypes trigger numerous warnings
+ifneq ($(SIM_TYPE),BOOZ)
+CFLAGS	+= -Wstrict-prototypes
+endif
+
+
 LDFLAGS		=	-lm					\
 
+ifeq ($(SIM_TYPE),BOOZ)
+LDFLAGS		+= $($(TARGET).LDFLAGS)
+endif
 #
 # General rules
 #
@@ -66,9 +79,17 @@ $(TARGET).objs	= $($(TARGET).objso:%.S=$(OBJDIR)/%.o)
 all compile: $(OBJDIR)/simsitl
 
 
+
+ifeq ($(SIM_TYPE),BOOZ)
+$(OBJDIR)/simsitl : $($(TARGET).objs)
+	@echo LD $@
+	$(Q)$(CC) -o $@ $($(TARGET).objs) $(LDFLAGS)
+else
 $(OBJDIR)/simsitl : $($(TARGET).objs) $(SITLCMA) $(SIMSITLML)
 	@echo LD $@
 	$(Q)$(OCAMLC) -custom $(CAMLINCLUDES) -o $@ unix.cma str.cma xml-light.cma glibivy-ocaml.cma lib-pprz.cma lablgtk.cma $($(TARGET).objs) gtkInit.cmo $(SITLCMA) $(SIMSITLML)
+endif
+
 
 
 # The id of the A/C is hardcoded in the code (to be improved with dynlink ?)
@@ -93,6 +114,11 @@ $(OBJDIR)/%.o: $(SRC_ARCH)/%.c
 $(OBJDIR)/%.o: $(SRC_ARCH)/%.S
 	$(CC) $(CFLAGS) -c -o $@ $<
 
+ifeq ($(SIM_TYPE),BOOZ)
+$(OBJDIR)/%.o: $(SIMDIR)/%.c
+	@echo CC $@
+	$(Q)$(CC) $(CFLAGS) -c -o $@ $<
+endif
 
 avr_clean:
 	rm -rf $(OBJDIR)
diff --git a/conf/autopilot/conf_booz.makefile b/conf/autopilot/conf_booz.makefile
index eabbdf80dc..51b4e32971 100644
--- a/conf/autopilot/conf_booz.makefile
+++ b/conf/autopilot/conf_booz.makefile
@@ -4,7 +4,7 @@ FLASH_MODE = IAP
 
 
 #
-# FILTER CPU
+# filter CPU
 #
 
 flt.ARCHDIR = $(ARCHI)
@@ -96,7 +96,7 @@ ctl.srcs += booz_estimator.c      \
             booz_autopilot.c
 
 #
-# Simulator
+# SITL Simulator
 #
 
 SIM_TYPE = BOOZ
@@ -106,12 +106,12 @@ sim.ARCH = sitl
 sim.TARGET = main
 sim.TARGETDIR = main
 
-#sim.srcs = $(SIMDIR)/main_booz_sim.c           \
-#	   $(SIMDIR)/booz_flight_model.c       \
-#           $(SIMDIR)/booz_flight_model_utils.c \
-#           $(SIMDIR)/booz_sensors_model.c      \
-#           $(SIMDIR)/booz_flightgear.c         \
-#           $(SIMDIR)/booz_joystick.c           \
+sim.srcs = $(SIMDIR)/main_booz_sim.c           \
+	   $(SIMDIR)/booz_flight_model.c       \
+           $(SIMDIR)/booz_flight_model_utils.c \
+           $(SIMDIR)/booz_sensors_model.c      \
+           $(SIMDIR)/booz_flightgear.c         \
+           $(SIMDIR)/booz_joystick.c           \
 
 sim.CFLAGS += -DSITL
 sim.CFLAGS += -DBOOZ_CONTROLLER_MCU
diff --git a/sw/airborne/Makefile b/sw/airborne/Makefile
index a123da0a0a..0123ed521c 100644
--- a/sw/airborne/Makefile
+++ b/sw/airborne/Makefile
@@ -25,6 +25,10 @@ OBJDIR = $(PAPARAZZI_HOME)/var/$(AIRCRAFT)/$(TARGET)
 VARINCLUDE=$(PAPARAZZI_HOME)/var/include
 ACINCLUDE = $(PAPARAZZI_HOME)/var/$(AIRCRAFT)
 
+#
+# WTF is that for ? VARINCLUDE=$(PAPARAZZI_HOME)/var/include  and  -I $(PAPARAZZI_SRC)/var/include in the line below ?
+#
+
 INCLUDES = -I $(PAPARAZZI_SRC)/sw/include -I $(PAPARAZZI_SRC)/var/include -I $(PAPARAZZI_SRC)/sw/airborne -I $(PAPARAZZI_SRC)/conf/autopilot -I $(PAPARAZZI_SRC)/sw/airborne/$($(TARGET).ARCHDIR) -I $(VARINCLUDE) -I $(ACINCLUDE)  
 
 SRC_ARCH = $(PAPARAZZI_SRC)/sw/airborne/$(ARCHDIR)
diff --git a/sw/airborne/multitilt.c b/sw/airborne/multitilt.c
index fdef19d1f4..16649af620 100644
--- a/sw/airborne/multitilt.c
+++ b/sw/airborne/multitilt.c
@@ -152,7 +152,7 @@ static inline void multitilt_predict( const float* gyro ) {
 
 }
 
-static void inline mtt_update_axis(float _err, float _P[2][2], float* angle, float* bias) {
+static inline void mtt_update_axis(float _err, float _P[2][2], float* angle, float* bias) {
   const float Pct_0 = _P[0][0];
   const float Pct_1 = _P[1][0];
   /* E = C P C' + R */
diff --git a/sw/airborne/sim/adc_hw.c b/sw/airborne/sim/adc_hw.c
index 71d7901746..ac60e63339 100644
--- a/sw/airborne/sim/adc_hw.c
+++ b/sw/airborne/sim/adc_hw.c
@@ -1,3 +1,5 @@
 #include "adc.h"
 
-void adc_buf_channel(uint8_t adc_channel, struct adc_buf* s, uint8_t av_nb_sample) {}
+void adc_buf_channel(uint8_t adc_channel __attribute__ ((unused)), 
+		     struct adc_buf* s __attribute__ ((unused)), 
+		     uint8_t av_nb_sample __attribute__ ((unused))) {}
diff --git a/sw/simulator/Makefile b/sw/simulator/Makefile
index 26d532423f..a526293282 100644
--- a/sw/simulator/Makefile
+++ b/sw/simulator/Makefile
@@ -92,88 +92,3 @@ clean :
 ifneq ($(MAKECMDGOALS),clean) 
 -include .depend
 endif
-
-AB=../airborne
-AB_ARCH=$(AB)/sim
-
-CC = gcc
-CFLAGS= -g -Wall `pkg-config glib-2.0 --cflags` -I /usr/include/meschach -I$(AB) -I../include -I../../var/BOOZ -I../../var/include -I../../conf/autopilot -I$(AB_ARCH)
-LDFLAGS=`pkg-config glib-2.0 --libs` -lm -lmeschach -lpcre
-
-
-BOOZ_SIM_SRCS = main_booz_sim.c           \
-	        booz_flight_model.c       \
-                booz_flight_model_utils.c \
-                booz_sensors_model.c      \
-                booz_flightgear.c         \
-                booz_joystick.c           \
-
-CFLAGS += -DSITL
-CFLAGS += -DBOOZ_CONTROLLER_MCU
-CFLAGS += -DCONFIG=\"conf_booz.h\"
-
-BOOZ_AB_SRCS += $(AB)/booz_controller_main.c
-
-BOOZ_AB_SRCS += $(AB)/sys_time.c
-
-CFLAGS += -DRADIO_CONTROL 
-BOOZ_AB_SRCS += $(AB)/radio_control.c \
-		$(AB_ARCH)/ppm_hw.c
-
-CFLAGS += -DACTUATORS=\"actuators_buss_twi_blmc_hw.h\" 
-BOOZ_AB_SRCS += $(AB)/actuators.c \
-                $(AB_ARCH)/actuators_buss_twi_blmc_hw.c \
-                $(AB)/i2c.c $(AB_ARCH)/i2c_hw.c
-
-CFLAGS += -DDOWNLINK 
-BOOZ_AB_SRCS += $(AB)/booz_controller_telemetry.c \
-                $(AB)/downlink.c
-
-#CFLAGS += -DDOWNLINK_TRANSPORT=PprzTransport -DPPRZ_UART=SimUart -DDOWNLINK_DEVICE=SimUart -DSIM_UART
-#BOOZ_AB_SRCS += ../airborne/pprz_transport.c  ../airborne/sim/sim_uart.c 
-
-CFLAGS += -DDOWNLINK_TRANSPORT=IvyTransport
-BOOZ_AB_SRCS += $(AB_ARCH)/ivy_transport.c
-LDFLAGS += -lglibivy
-
-BOOZ_AB_SRCS += $(AB)/booz_inter_mcu.c
-CFLAGS += -DUSE_SPI
-BOOZ_AB_SRCS += $(AB)/booz_link_mcu.c $(AB_ARCH)/booz_link_mcu_hw.c
-BOOZ_AB_SRCS += $(AB)/spi.c $(AB_ARCH)/spi_hw.c
-
-#CFLAGS += -DDATALINK=PPRZ
-#BOOZ_AB_SRCS += ../airborne/datalink.c
-BOOZ_AB_SRCS += $(AB)/booz_estimator.c
-BOOZ_AB_SRCS += $(AB)/booz_control.c
-BOOZ_AB_SRCS += $(AB)/booz_nav.c
-BOOZ_AB_SRCS += $(AB)/booz_nav_hover.c
-
-BOOZ_AB_SRCS += $(AB)/booz_autopilot.c
-BOOZ_AB_SRCS += $(AB)/commands.c
-
-
-CFLAGS += -DBOOZ_FILTER_MCU
-BOOZ_AB_SRCS += $(AB)/booz_filter_main.c
-
-CFLAGS += -DADC_CHANNEL_AX=1 -DADC_CHANNEL_AY=2 -DADC_CHANNEL_AZ=3 -DADC_CHANNEL_BAT=4
-BOOZ_AB_SRCS  += $(AB_ARCH)/adc_hw.c
-
-
-BOOZ_AB_SRCS += $(AB)/booz_filter_telemetry.c
-
-BOOZ_AB_SRCS  += $(AB)/max1167.c $(AB_ARCH)/max1167_hw.c
-BOOZ_AB_SRCS  += $(AB)/micromag.c $(AB_ARCH)/micromag_hw.c
-BOOZ_AB_SRCS  += $(AB)/imu_v3.c $(AB_ARCH)/imu_v3_hw.c
-
-
-BOOZ_AB_SRCS += $(AB)/booz_ahrs.c
-CFLAGS += -DBOOZ_AHRS_TYPE=BOOZ_AHRS_MULTITILT
-BOOZ_AB_SRCS += $(AB)/multitilt.c
-#CFLAGS += -DBOOZ_AHRS_TYPE=BOOZ_AHRS_QUATERNION -DEKF_UPDATE_DISCRETE
-#BOOZ_AB_SRCS += $(AB)/ahrs_quat_fast_ekf.c 
-
-#$(OBJDIR)/%.c: %.o
-#	$(CC) $(CFLAGS) -c -o $@ $<
-
-booz_sim: $(BOOZ_SIM_SRCS) $(BOOZ_AB_SRCS)
-	$(CC) $(CFLAGS) -g -o $@ $^ $(LDFLAGS)
diff --git a/sw/simulator/booz_flight_model.c b/sw/simulator/booz_flight_model.c
index 2245f83b20..93c9fa378e 100644
--- a/sw/simulator/booz_flight_model.c
+++ b/sw/simulator/booz_flight_model.c
@@ -157,7 +157,7 @@ static VEC* booz_get_forces_body_frame( VEC* X, VEC* F , MAT* dcm, VEC* omega_sq
    compute the sum of external moments. 
    assumes that omega_square is already precomputed from X 
 */
-static VEC* booz_get_moments_body_frame( VEC* X, VEC* M, VEC* omega_square ) {
+static VEC* booz_get_moments_body_frame( VEC* X __attribute__ ((unused)), VEC* M, VEC* omega_square ) {
   M =  mv_mlt(bfm.props_moment_matrix, omega_square, M);
   return M;
 }
diff --git a/sw/simulator/booz_joystick.c b/sw/simulator/booz_joystick.c
index b345f50f38..9811c2784e 100644
--- a/sw/simulator/booz_joystick.c
+++ b/sw/simulator/booz_joystick.c
@@ -41,7 +41,9 @@ void booz_joystick_init(const char* device) {
 }
 
 
-static gboolean on_data_received(GIOChannel *source, GIOCondition condition, gpointer data) {
+static gboolean on_data_received(GIOChannel *source, 
+				 GIOCondition condition __attribute__ ((unused)), 
+				 gpointer data __attribute__ ((unused))) {
 
   struct js_event js;
   gsize len;
diff --git a/sw/simulator/booz_sensors_model.c b/sw/simulator/booz_sensors_model.c
index edab64e64d..fda9d0ece9 100644
--- a/sw/simulator/booz_sensors_model.c
+++ b/sw/simulator/booz_sensors_model.c
@@ -392,6 +392,6 @@ static VEC* v_add_gaussian_noise(VEC* in, VEC* std_dev, VEC* out) {
   one = v_ones(one);
   tmp = v_mltadd(one, tmp, -2., tmp); 
   tmp = v_star(tmp, std_dev, tmp);
-  out = v_add(out, tmp, out);
+  out = v_add(in, tmp, out);
   return out;
 }
diff --git a/sw/simulator/main_booz_sim.c b/sw/simulator/main_booz_sim.c
index dcd3e9e376..86e8b1569b 100644
--- a/sw/simulator/main_booz_sim.c
+++ b/sw/simulator/main_booz_sim.c
@@ -52,7 +52,7 @@ static void on_DL_SETTING(IvyClientPtr app, void *user_data, int argc, char *arg
 
 volatile bool_t ppm_valid;
 
-static gboolean booz_sim_periodic(gpointer data) {
+static gboolean booz_sim_periodic(gpointer data __attribute__ ((unused))) {
   /* read actuators positions */
   booz_sim_read_actuators();
 
@@ -80,7 +80,7 @@ static gboolean booz_sim_periodic(gpointer data) {
   /* this will update the controller estimator                          */
   booz_controller_main_event_task();
   /* cheat in simulation : psi not available from filter yet */
-  booz_estimator_set_psi(bfm.state->ve[BFMS_PSI]);
+  //  booz_estimator_set_psi(bfm.state->ve[BFMS_PSI]);
   /* in simulation compute dcm as a helper for for nav */
   booz_estimator_compute_dcm();
   /* in simulation feed speed and pos estimations ( with a pos sensor :( ) */
@@ -360,7 +360,9 @@ static void ivy_transport_init(void) {
 #include "std.h"
 #include "settings.h"
 #include "booz_controller_telemetry.h"
-static void on_DL_SETTING(IvyClientPtr app, void *user_data, int argc, char *argv[]){
+static void on_DL_SETTING(IvyClientPtr app __attribute__ ((unused)), 
+			  void *user_data __attribute__ ((unused)), 
+			  int argc __attribute__ ((unused)), char *argv[]){
   uint8_t index = atoi(argv[2]);
   float value = atof(argv[3]);
   DlSetting(index, value);
@@ -404,3 +406,8 @@ static void sim_uart_init(void) {
 
 
 
+
+
+
+
+