diff --git a/Makefile b/Makefile
index faf553d497..55ce5fde37 100644
--- a/Makefile
+++ b/Makefile
@@ -191,7 +191,7 @@ help:
 test_all_example_airframes:
 	make AIRCRAFT=TJ1     clean_ac ap
 	make AIRCRAFT=MJ4     clean_ac ap
-	make AIRCRAFT=Slayer  clean_ac ac
+	make AIRCRAFT=Slayer  clean_ac ap
 	make AIRCRAFT=Plaster clean_ac sim ac	
 	make AIRCRAFT=Twin4   clean_ac ac
 	make AIRCRAFT=Tux     clean_ac ac
diff --git a/conf/airframes/gorrazoptere_esc_3DMG.xml b/conf/airframes/gorrazoptere_esc_3DMG.xml
index 816ecc8b79..776749ef52 100644
--- a/conf/airframes/gorrazoptere_esc_3DMG.xml
+++ b/conf/airframes/gorrazoptere_esc_3DMG.xml
@@ -140,7 +140,7 @@ include $(PAPARAZZI_SRC)/conf/autopilot/disc_board.makefile
 ap.srcs += commands.c
 
 ap.CFLAGS += -DACTUATORS=\"servos_esc_hw.h\" -DTIMER3 -DTIMER1_TOP=0x400
-ap.srcs += $(SRC_ARCH)/servos_esc_hw.c
+ap.srcs += $(SRC_ARCH)/servos_esc_hw.c actuators.c
 
 ap.CFLAGS += -DRADIO_CONTROL -DRADIO_CONTROL_TYPE=RC_FUTABA
 ap.srcs += radio_control.c $(SRC_ARCH)/ppm_hw.c 
diff --git a/conf/airframes/slayer1.xml b/conf/airframes/slayer1.xml
index b4a6fe5f61..f9e7098212 100644
--- a/conf/airframes/slayer1.xml
+++ b/conf/airframes/slayer1.xml
@@ -65,6 +65,7 @@
   </section>
  
   <section name="GYRO" prefix="GYRO_">
+    <define name="ADC_ROLL_COEF" value="1"/>
     <define name="ADC_ROLL_NEUTRAL" value="503"/>
     <define name="ADC_PITCH_NEUTRAL" value="469"/>   
   </section>
@@ -164,7 +165,7 @@ ap.srcs = sys_time.c $(SRC_ARCH)/sys_time_hw.c $(SRC_ARCH)/armVIC.c main_fbw.c m
 ap.srcs += commands.c
 
 ap.CFLAGS += -DACTUATORS=\"servos_4015_hw.h\" -DSERVOS_4015
-ap.srcs += $(SRC_ARCH)/servos_4015_hw.c
+ap.srcs += $(SRC_ARCH)/servos_4015_hw.c actuators.c
 
 ap.CFLAGS += -DRADIO_CONTROL -DRADIO_CONTROL_TYPE=RC_FUTABA
 ap.srcs += radio_control.c $(SRC_ARCH)/ppm_hw.c  
diff --git a/sw/airborne/gps.h b/sw/airborne/gps.h
index 2d131adb5a..d5a1507f60 100644
--- a/sw/airborne/gps.h
+++ b/sw/airborne/gps.h
@@ -35,8 +35,12 @@
 
 #ifdef UBX
 #include "gps_ubx.h"
+#elif defined SITL
+#define GPS_NB_CHANNELS 16
+#define GPS_FIX_VALID(gps_mode) (gps_mode == 3)
 #endif
 
+
 extern uint8_t gps_mode; /* Receiver status */
 extern uint32_t gps_itow;    /* ms */
 extern int32_t  gps_alt;    /* cm       */