diff --git a/ArduCopter/Copter.h b/ArduCopter/Copter.h
index 05e62895f5..af34398640 100644
--- a/ArduCopter/Copter.h
+++ b/ArduCopter/Copter.h
@@ -364,7 +364,7 @@ private:
             uint8_t motor_interlock_switch  : 1; // 22      // true if pilot is requesting motor interlock enable
             uint8_t in_arming_delay         : 1; // 23      // true while we are armed but waiting to spin motors
             uint8_t initialised_params      : 1; // 24      // true when the all parameters have been initialised. we cannot send parameters to the GCS until this is done
-            uint8_t unused3   : 1; // 25      // was compass_init_location; true when the compass's initial location has been set
+            uint8_t unused3                 : 1; // 25      // was compass_init_location; true when the compass's initial location has been set
             uint8_t unused2                 : 1; // 26      // aux switch rc_override is allowed
             uint8_t armed_with_switch       : 1; // 27      // we armed using a arming switch
         };