diff --git a/message_definitions/v1.0/ardupilotmega.xml b/message_definitions/v1.0/ardupilotmega.xml
index 0430986a199..33e0e9d6e62 100644
--- a/message_definitions/v1.0/ardupilotmega.xml
+++ b/message_definitions/v1.0/ardupilotmega.xml
@@ -23,6 +23,7 @@
     <enum name="HEADING_TYPE">
       <entry value="0" name="HEADING_TYPE_COURSE_OVER_GROUND"/>
       <entry value="1" name="HEADING_TYPE_HEADING"/>
+      <entry value="2" name="HEADING_TYPE_DEFAULT"/>
     </enum>
     <!-- ardupilot specific MAV_CMD_* commands -->
     <enum name="MAV_CMD">