diff --git a/ROMFS/px4fmu_common/init.d/rcS b/ROMFS/px4fmu_common/init.d/rcS
index 99b5dc2b14..2bd2b92fa4 100644
--- a/ROMFS/px4fmu_common/init.d/rcS
+++ b/ROMFS/px4fmu_common/init.d/rcS
@@ -628,19 +628,19 @@ then
 	fi
 	if param compare SYS_COMPANION 319200
 	then
-		mavlink start -d ${MAVLINK_COMPANION_DEVICE} -b 19200 -r 1000
+		mavlink start -d ${MAVLINK_COMPANION_DEVICE} -b 19200 -r 1000 -f
 	fi
 	if param compare SYS_COMPANION 338400
 	then
-		mavlink start -d ${MAVLINK_COMPANION_DEVICE} -b 38400 -r 1000
+		mavlink start -d ${MAVLINK_COMPANION_DEVICE} -b 38400 -r 1000 -f
 	fi
 	if param compare SYS_COMPANION 357600
 	then
-		mavlink start -d ${MAVLINK_COMPANION_DEVICE} -b 57600 -r 1000
+		mavlink start -d ${MAVLINK_COMPANION_DEVICE} -b 57600 -r 1000 -f
 	fi
 	if param compare SYS_COMPANION 3115200
 	then
-		mavlink start -d ${MAVLINK_COMPANION_DEVICE} -b 115200 -r 1000
+		mavlink start -d ${MAVLINK_COMPANION_DEVICE} -b 115200 -r 1000 -f
 	fi
 	if param compare SYS_COMPANION 419200
 	then