diff --git a/libraries/AP_Common/Location.cpp b/libraries/AP_Common/Location.cpp
index 506467af10..158eef76cb 100644
--- a/libraries/AP_Common/Location.cpp
+++ b/libraries/AP_Common/Location.cpp
@@ -231,6 +231,14 @@ Vector2f Location::get_distance_NE(const Location &loc2) const
                     (loc2.lng - lng) * LOCATION_SCALING_FACTOR * longitude_scale());
 }
 
+// return the distance in meters in North/East/Down plane as a N/E/D vector to loc2
+Vector3f Location::get_distance_NED(const Location &loc2) const
+{
+    return Vector3f((loc2.lat - lat) * LOCATION_SCALING_FACTOR,
+                    (loc2.lng - lng) * LOCATION_SCALING_FACTOR * longitude_scale(),
+                    (alt - loc2.alt) * 0.01f);
+}
+
 // extrapolate latitude/longitude given distances (in meters) north and east
 void Location::offset(float ofs_north, float ofs_east)
 {
diff --git a/libraries/AP_Common/Location.h b/libraries/AP_Common/Location.h
index 471eab591a..9987e124a6 100644
--- a/libraries/AP_Common/Location.h
+++ b/libraries/AP_Common/Location.h
@@ -72,6 +72,9 @@ public:
     // return distance in meters between two locations
     float get_distance(const struct Location &loc2) const;
 
+    // return the distance in meters in North/East/Down plane as a N/E/D vector to loc2
+    Vector3f get_distance_NED(const Location &loc2) const;
+
     // return the distance in meters in North/East plane as a N/E vector to loc2
     Vector2f get_distance_NE(const Location &loc2) const;
 
diff --git a/libraries/AP_Math/location.cpp b/libraries/AP_Math/location.cpp
index 760be2b8b1..69b68c1fe3 100644
--- a/libraries/AP_Math/location.cpp
+++ b/libraries/AP_Math/location.cpp
@@ -77,16 +77,6 @@ float location_path_proportion(const struct Location &location,
 
 
 
-/*
-  return the distance in meters in North/East/Down plane as a N/E/D vector
-  from loc1 to loc2
- */
-Vector3f location_3d_diff_NED(const struct Location &loc1, const struct Location &loc2)
-{
-    return Vector3f((loc2.lat - loc1.lat) * LOCATION_SCALING_FACTOR,
-                    (loc2.lng - loc1.lng) * LOCATION_SCALING_FACTOR * loc1.longitude_scale(),
-                    (loc1.alt - loc2.alt) * 0.01f);
-}
 
 
 // return true when lat and lng are within range
diff --git a/libraries/AP_Math/location.h b/libraries/AP_Math/location.h
index 292b3e3952..354980e834 100644
--- a/libraries/AP_Math/location.h
+++ b/libraries/AP_Math/location.h
@@ -42,12 +42,6 @@ float       location_path_proportion(const struct Location &location,
                                const struct Location &point1,
                                const struct Location &point2);
 
-/*
-  return the distance in meters in North/East/Down plane as a N/E/D vector
-  from loc1 to loc2
- */
-Vector3f    location_3d_diff_NED(const struct Location &loc1, const struct Location &loc2);
-
 
 // Converts from WGS84 geodetic coordinates (lat, lon, height)
 // into WGS84 Earth Centered, Earth Fixed (ECEF) coordinates