diff --git a/AntennaTracker/GCS_Mavlink.cpp b/AntennaTracker/GCS_Mavlink.cpp
index 7db3bc6e2a..fc9373aa19 100644
--- a/AntennaTracker/GCS_Mavlink.cpp
+++ b/AntennaTracker/GCS_Mavlink.cpp
@@ -15,12 +15,14 @@
  *  pattern below when adding any new messages
  */
 
-void Tracker::send_heartbeat(mavlink_channel_t chan)
+MAV_TYPE GCS_MAVLINK_Tracker::frame_type() const
 {
-    uint8_t base_mode = MAV_MODE_FLAG_CUSTOM_MODE_ENABLED;
-    uint8_t system_status = MAV_STATE_ACTIVE;
-    uint32_t custom_mode = control_mode;
+    return MAV_TYPE_ANTENNA_TRACKER;
+}
 
+MAV_MODE GCS_MAVLINK_Tracker::base_mode() const
+{
+    uint8_t base_mode = MAV_MODE_FLAG_CUSTOM_MODE_ENABLED;
     // work out the base_mode. This value is not very useful
     // for APM, but we calculate it as best we can so a generic
     // MAVLink enabled ground station can work out something about
@@ -29,7 +31,7 @@ void Tracker::send_heartbeat(mavlink_channel_t chan)
     // only get useful information from the custom_mode, which maps to
     // the APM flight mode and has a well defined meaning in the
     // ArduPlane documentation
-    switch (control_mode) {
+    switch (tracker.control_mode) {
     case MANUAL:
         base_mode |= MAV_MODE_FLAG_MANUAL_INPUT_ENABLED;
         break;
@@ -48,7 +50,6 @@ void Tracker::send_heartbeat(mavlink_channel_t chan)
         break;
 
     case INITIALISING:
-        system_status = MAV_STATE_CALIBRATING;
         break;
     }
 
@@ -57,10 +58,20 @@ void Tracker::send_heartbeat(mavlink_channel_t chan)
         base_mode |= MAV_MODE_FLAG_SAFETY_ARMED;
     }
 
-    gcs().chan(chan-MAVLINK_COMM_0).send_heartbeat(MAV_TYPE_ANTENNA_TRACKER,
-                                            base_mode,
-                                            custom_mode,
-                                            system_status);
+    return (MAV_MODE)base_mode;
+}
+
+uint32_t GCS_MAVLINK_Tracker::custom_mode() const
+{
+    return tracker.control_mode;
+}
+
+MAV_STATE GCS_MAVLINK_Tracker::system_status() const
+{
+    if (tracker.control_mode == INITIALISING) {
+        return MAV_STATE_CALIBRATING;
+    }
+    return MAV_STATE_ACTIVE;
 }
 
 void Tracker::send_attitude(mavlink_channel_t chan)
@@ -167,7 +178,7 @@ bool GCS_MAVLINK_Tracker::try_send_message(enum ap_message id)
     case MSG_HEARTBEAT:
         CHECK_PAYLOAD_SIZE(HEARTBEAT);
         last_heartbeat_time = AP_HAL::millis();
-        tracker.send_heartbeat(chan);
+        send_heartbeat();
         return true;
 
     case MSG_ATTITUDE:
diff --git a/AntennaTracker/GCS_Mavlink.h b/AntennaTracker/GCS_Mavlink.h
index 8545332b1f..c2a131ff38 100644
--- a/AntennaTracker/GCS_Mavlink.h
+++ b/AntennaTracker/GCS_Mavlink.h
@@ -39,4 +39,8 @@ private:
     void handle_change_alt_request(AP_Mission::Mission_Command &cmd) override;
     bool try_send_message(enum ap_message id) override;
 
+    MAV_TYPE frame_type() const override;
+    MAV_MODE base_mode() const override;
+    uint32_t custom_mode() const override;
+    MAV_STATE system_status() const override;
 };
diff --git a/AntennaTracker/Tracker.h b/AntennaTracker/Tracker.h
index 1d35e62ec6..9568852469 100644
--- a/AntennaTracker/Tracker.h
+++ b/AntennaTracker/Tracker.h
@@ -202,7 +202,6 @@ private:
 
     void one_second_loop();
     void ten_hz_logging_loop();
-    void send_heartbeat(mavlink_channel_t chan);
     void send_attitude(mavlink_channel_t chan);
     void send_extended_status1(mavlink_channel_t chan);
     void send_location(mavlink_channel_t chan);