diff --git a/libraries/AP_Mount/AP_Mount_Backend.cpp b/libraries/AP_Mount/AP_Mount_Backend.cpp
index 5fc2a3cff0339..de45386f1668a 100644
--- a/libraries/AP_Mount/AP_Mount_Backend.cpp
+++ b/libraries/AP_Mount/AP_Mount_Backend.cpp
@@ -857,12 +857,14 @@ uint16_t AP_Mount_Backend::get_gimbal_device_flags() const
         break;
     }
 
+    const uint16_t yaw_ef_flags = GIMBAL_DEVICE_FLAGS_YAW_IN_EARTH_FRAME | GIMBAL_DEVICE_FLAGS_YAW_LOCK;
+    const uint16_t yaw_bf_flags = GIMBAL_DEVICE_FLAGS_YAW_IN_VEHICLE_FRAME;
+
     const uint16_t flags = (get_mode() == MAV_MOUNT_MODE_RETRACT ? GIMBAL_DEVICE_FLAGS_RETRACT : 0) |
                            (get_mode() == MAV_MOUNT_MODE_NEUTRAL ? GIMBAL_DEVICE_FLAGS_NEUTRAL : 0) |
-                           GIMBAL_DEVICE_FLAGS_ROLL_LOCK | // roll angle is always earth-frame
-                           GIMBAL_DEVICE_FLAGS_PITCH_LOCK| // pitch angle is always earth-frame, yaw_angle is always body-frame
-                           GIMBAL_DEVICE_FLAGS_YAW_IN_VEHICLE_FRAME | // yaw angle is always in vehicle-frame
-                           (yaw_lock_state ? GIMBAL_DEVICE_FLAGS_YAW_LOCK : 0);
+                           GIMBAL_DEVICE_FLAGS_ROLL_LOCK  | // roll angle is always earth-frame
+                           GIMBAL_DEVICE_FLAGS_PITCH_LOCK | // pitch angle is always earth-frame
+                           (yaw_lock_state ? yaw_ef_flags : yaw_bf_flags); // yaw angle can be either earth-frame or body-frame
     return flags;
 }
 
diff --git a/libraries/AP_Mount/AP_Mount_Backend.h b/libraries/AP_Mount/AP_Mount_Backend.h
index 56706d7463c98..d64a0e2bbed92 100644
--- a/libraries/AP_Mount/AP_Mount_Backend.h
+++ b/libraries/AP_Mount/AP_Mount_Backend.h
@@ -288,7 +288,7 @@ class AP_Mount_Backend
     void update_angle_target_from_rate(const MountTarget& rate_rad, MountTarget& angle_rad) const;
 
     // helper function to provide GIMBAL_DEVICE_FLAGS for use in GIMBAL_DEVICE_ATTITUDE_STATUS message
-    uint16_t get_gimbal_device_flags() const;
+    virtual uint16_t get_gimbal_device_flags() const;
 
     // sent warning to GCS
     void send_warning_to_GCS(const char* warning_str);
diff --git a/libraries/AP_Mount/AP_Mount_Servo.cpp b/libraries/AP_Mount/AP_Mount_Servo.cpp
index 2f926c7d848a3..384364d5761a3 100644
--- a/libraries/AP_Mount/AP_Mount_Servo.cpp
+++ b/libraries/AP_Mount/AP_Mount_Servo.cpp
@@ -139,6 +139,22 @@ bool AP_Mount_Servo::get_attitude_quaternion(Quaternion& att_quat)
     return true;
 }
 
+// helper function to provide GIMBAL_DEVICE_FLAGS for use in GIMBAL_DEVICE_ATTITUDE_STATUS message
+uint16_t AP_Mount_Servo::get_gimbal_device_flags() const
+{
+    uint16_t flags = AP_Mount_Backend::get_gimbal_device_flags();
+    // per get_attitude_quaternion() above, angles are all body frame, so clear all the LOCK flags...
+    const uint16_t mask = ~(GIMBAL_DEVICE_FLAGS_ROLL_LOCK  |
+                            GIMBAL_DEVICE_FLAGS_PITCH_LOCK |
+                            GIMBAL_DEVICE_FLAGS_YAW_LOCK   |
+                            GIMBAL_DEVICE_FLAGS_YAW_IN_EARTH_FRAME);
+    flags &= mask;
+    // and set the YAW_IN_VEHICLE_FRAME flag
+    flags |= GIMBAL_DEVICE_FLAGS_YAW_IN_VEHICLE_FRAME;
+
+    return flags;
+}
+
 // private methods
 
 // update body-frame angle outputs from earth-frame angle targets
diff --git a/libraries/AP_Mount/AP_Mount_Servo.h b/libraries/AP_Mount/AP_Mount_Servo.h
index 529a97bd7341c..7bef2a1cd2cb7 100644
--- a/libraries/AP_Mount/AP_Mount_Servo.h
+++ b/libraries/AP_Mount/AP_Mount_Servo.h
@@ -39,6 +39,9 @@ class AP_Mount_Servo : public AP_Mount_Backend
     // get attitude as a quaternion.  returns true on success
     bool get_attitude_quaternion(Quaternion& att_quat) override;
 
+    // helper function to provide GIMBAL_DEVICE_FLAGS for use in GIMBAL_DEVICE_ATTITUDE_STATUS message
+    uint16_t get_gimbal_device_flags() const override;
+
 private:
 
     // update body-frame angle outputs from earth-frame targets