diff --git a/APMrover2/Log.pde b/APMrover2/Log.pde
index 762917dbe7..9859051a89 100644
--- a/APMrover2/Log.pde
+++ b/APMrover2/Log.pde
@@ -447,6 +447,26 @@ static void Log_Write_Compass()
         motor_offset_z  : (int16_t)mag_motor_offsets.z
     };
     DataFlash.WriteBlock(&pkt, sizeof(pkt));
+#if COMPASS_MAX_INSTANCES > 1
+    if (compass.get_count() > 1) {
+        const Vector3f &mag2_offsets = compass.get_offsets(1);
+        const Vector3f &mag2_motor_offsets = compass.get_motor_offsets(1);
+        const Vector3f &mag2 = compass.get_field(1);
+        struct log_Compass pkt2 = {
+            LOG_PACKET_HEADER_INIT(LOG_COMPASS2_MSG),
+            mag_x           : (int16_t)mag2.x,
+            mag_y           : (int16_t)mag2.y,
+            mag_z           : (int16_t)mag2.z,
+            offset_x        : (int16_t)mag2_offsets.x,
+            offset_y        : (int16_t)mag2_offsets.y,
+            offset_z        : (int16_t)mag2_offsets.z,
+            motor_offset_x  : (int16_t)mag2_motor_offsets.x,
+            motor_offset_y  : (int16_t)mag2_motor_offsets.y,
+            motor_offset_z  : (int16_t)mag2_motor_offsets.z
+        };
+        DataFlash.WriteBlock(&pkt2, sizeof(pkt2));
+    }
+#endif
 }
 
 
@@ -474,6 +494,8 @@ static const struct LogStructure log_structure[] PROGMEM = {
       "MODE", "MB",          "Mode,ModeNum" },
     { LOG_COMPASS_MSG, sizeof(log_Compass),             
       "MAG", "hhhhhhhhh",   "MagX,MagY,MagZ,OfsX,OfsY,OfsZ,MOfsX,MOfsY,MOfsZ" },
+    { LOG_COMPASS2_MSG, sizeof(log_Compass),             
+      "MAG2", "hhhhhhhhh",   "MagX,MagY,MagZ,OfsX,OfsY,OfsZ,MOfsX,MOfsY,MOfsZ" },
 };
 
 
diff --git a/APMrover2/defines.h b/APMrover2/defines.h
index 2014c5a3fd..9b4a5b90a4 100644
--- a/APMrover2/defines.h
+++ b/APMrover2/defines.h
@@ -125,6 +125,7 @@ enum ap_message {
 #define LOG_MODE_MSG            0x09
 #define LOG_COMPASS_MSG         0x0A
 #define LOG_CAMERA_MSG          0x0B
+#define LOG_COMPASS2_MSG        0x0C
 
 #define TYPE_AIRSTART_MSG		0x00
 #define TYPE_GROUNDSTART_MSG	0x01