diff --git a/sw/airborne/autopilot/main.c b/sw/airborne/autopilot/main.c
index 34e1be9447..9e8ceb7925 100644
--- a/sw/airborne/autopilot/main.c
+++ b/sw/airborne/autopilot/main.c
@@ -527,7 +527,8 @@ void use_gps_pos( void ) {
   
   static uint8_t i;
   if (i == gps_nb_channels) i = 0;
-  DOWNLINK_SEND_SVINFO(&i, &gps_svinfos[i].svid, &gps_svinfos[i].flags, &gps_svinfos[i].qi, &gps_svinfos[i].cno, &gps_svinfos[i].elev, &gps_svinfos[i].azim);
+  if (i < gps_nb_channels)
+    DOWNLINK_SEND_SVINFO(&i, &gps_svinfos[i].svid, &gps_svinfos[i].flags, &gps_svinfos[i].qi, &gps_svinfos[i].cno, &gps_svinfos[i].elev, &gps_svinfos[i].azim);
 
   if (!estimator_flight_time && (estimator_hspeed_mod > MIN_SPEED_FOR_TAKEOFF)) {
     estimator_flight_time = 1;