diff --git a/libraries/GCS_MAVLink/message_definitions/common.xml b/libraries/GCS_MAVLink/message_definitions/common.xml
index d933eeb7ff..1b7253caa5 100644
--- a/libraries/GCS_MAVLink/message_definitions/common.xml
+++ b/libraries/GCS_MAVLink/message_definitions/common.xml
@@ -426,6 +426,12 @@
Local coordinate frame, Z-down (x: east, y: north, z: up)
+
+ Global coordinate frame, WGS84 coordinate system. First value / x: latitude in degrees*1.0e-7, second value / y: longitude in degrees*1.0e-7, third value / z: positive altitude over mean sea level (MSL)
+
+
+ Global coordinate frame, WGS84 coordinate system, relative altitude over ground with respect to the home position. First value / x: latitude in degrees*10e-7, second value / y: longitude in degrees*10e-7, third value / z: positive altitude with 0 being at the altitude of the home location.
+
Offset to the current local frame. Anything expressed in this frame should be added to the current local frame position.
@@ -438,6 +444,9 @@
Global coordinate frame with above terrain level altitude. WGS84 coordinate system, relative altitude over terrain with respect to the waypoint coordinate. First value / x: latitude in degrees, second value / y: longitude in degrees, third value / z: positive altitude in meters with 0 being at ground level in terrain model.
+
+ Global coordinate frame with above terrain level altitude. WGS84 coordinate system, relative altitude over terrain with respect to the waypoint coordinate. First value / x: latitude in degrees*10e-7, second value / y: longitude in degrees*10e-7, third value / z: positive altitude in meters with 0 being at ground level in terrain model.
+