diff --git a/ArduCopter/AP_Arming.cpp b/ArduCopter/AP_Arming.cpp
index 7cd5620d2c..991afc094f 100644
--- a/ArduCopter/AP_Arming.cpp
+++ b/ArduCopter/AP_Arming.cpp
@@ -456,11 +456,14 @@ bool AP_Arming_Copter::arm_checks(AP_Arming::Method method)
     }
 
 #ifndef ALLOW_ARM_NO_COMPASS
-    const Compass &_compass = AP::compass();
-    // check compass health
-    if (!_compass.healthy()) {
-        check_failed(ARMING_CHECK_NONE, true, "Compass not healthy");
-        return false;
+    // if external source of heading is available, we can skip compass health check
+    if (!ahrs.is_ext_nav_used_for_yaw()) {
+        const Compass &_compass = AP::compass();
+        // check compass health
+        if (!_compass.healthy()) {
+            check_failed(ARMING_CHECK_NONE, true, "Compass not healthy");
+            return false;
+        }
     }
 #endif