diff --git a/libraries/GCS_MAVLink/GCS.h b/libraries/GCS_MAVLink/GCS.h
index 26fc6ed74c..4d6643c3ce 100644
--- a/libraries/GCS_MAVLink/GCS.h
+++ b/libraries/GCS_MAVLink/GCS.h
@@ -863,7 +863,7 @@ private:
     void send_distance_sensor(const class AP_RangeFinder_Backend *sensor, const uint8_t instance) const;
 
     virtual bool handle_guided_request(AP_Mission::Mission_Command &cmd) = 0;
-    virtual void handle_change_alt_request(AP_Mission::Mission_Command &cmd) = 0;
+    virtual void handle_change_alt_request(AP_Mission::Mission_Command &cmd) {};
     void handle_common_mission_message(const mavlink_message_t &msg);
 
     void handle_vicon_position_estimate(const mavlink_message_t &msg);
diff --git a/libraries/GCS_MAVLink/GCS_Dummy.h b/libraries/GCS_MAVLink/GCS_Dummy.h
index eb956b7d85..b1bcdd9277 100644
--- a/libraries/GCS_MAVLink/GCS_Dummy.h
+++ b/libraries/GCS_MAVLink/GCS_Dummy.h
@@ -23,7 +23,6 @@ private:
     void handleMessage(const mavlink_message_t &msg) override {}
     bool try_send_message(enum ap_message id) override { return true; }
     bool handle_guided_request(AP_Mission::Mission_Command &cmd) override { return true; }
-    void handle_change_alt_request(AP_Mission::Mission_Command &cmd) override {}
 
 protected: