diff --git a/libraries/AP_SmartRTL/AP_SmartRTL.cpp b/libraries/AP_SmartRTL/AP_SmartRTL.cpp
index a577cc4989..26280e5fde 100644
--- a/libraries/AP_SmartRTL/AP_SmartRTL.cpp
+++ b/libraries/AP_SmartRTL/AP_SmartRTL.cpp
@@ -834,7 +834,7 @@ void AP_SmartRTL::deactivate(SRTL_Actions action, const char *reason)
 }
 
 // logging
-void AP_SmartRTL::log_action(SRTL_Actions action, const Vector3f &point)
+void AP_SmartRTL::log_action(SRTL_Actions action, const Vector3f &point) const
 {
     if (!_example_mode) {
         AP::logger().Write_SRTL(_active, _path_points_count, _path_points_max, action, point);
diff --git a/libraries/AP_SmartRTL/AP_SmartRTL.h b/libraries/AP_SmartRTL/AP_SmartRTL.h
index 08a4631c2c..a583729c0a 100644
--- a/libraries/AP_SmartRTL/AP_SmartRTL.h
+++ b/libraries/AP_SmartRTL/AP_SmartRTL.h
@@ -159,7 +159,7 @@ private:
     void deactivate(SRTL_Actions action, const char *reason);
 
     // logging
-    void log_action(SRTL_Actions action, const Vector3f &point = Vector3f());
+    void log_action(SRTL_Actions action, const Vector3f &point = Vector3f()) const;
 
     // parameters
     AP_Float _accuracy;