diff --git a/libraries/AP_Compass/CompassCalibrator.cpp b/libraries/AP_Compass/CompassCalibrator.cpp
index b14ff39eb4..031fa0a006 100644
--- a/libraries/AP_Compass/CompassCalibrator.cpp
+++ b/libraries/AP_Compass/CompassCalibrator.cpp
@@ -768,23 +768,6 @@ Vector3f CompassCalibrator::calculate_earth_field(CompassSample &sample, enum Ro
     return efield;
 }
 
-/*
-  return true if two rotations are equivalent
-  This copes with the fact that we have some duplicates, like ROLL_180_YAW_90 and PITCH_180_YAW_270
- */
-bool CompassCalibrator::rotation_equal(enum Rotation r1, enum Rotation r2) const
-{
-    if (r1 == r2) {
-        return true;
-    }
-    Vector3f v(1,2,3);
-    Vector3f v1 = v;
-    Vector3f v2 = v;
-    v1.rotate(r1);
-    v2.rotate(r2);
-    return (v1 - v2).length() < 0.001;
-}
-
 /*
   calculate compass orientation using the attitude estimate associated
   with each sample, and fix orientation on external compasses if
diff --git a/libraries/AP_Compass/CompassCalibrator.h b/libraries/AP_Compass/CompassCalibrator.h
index 3f339d5143..dadf00d564 100644
--- a/libraries/AP_Compass/CompassCalibrator.h
+++ b/libraries/AP_Compass/CompassCalibrator.h
@@ -171,5 +171,4 @@ private:
 
     Vector3f calculate_earth_field(CompassSample &sample, enum Rotation r);
     bool calculate_orientation();
-    bool rotation_equal(enum Rotation r1, enum Rotation r2) const;
 };