diff --git a/libraries/AP_NavEKF/AP_NavEKF.cpp b/libraries/AP_NavEKF/AP_NavEKF.cpp
index 61d83a1030..19ac54a19e 100644
--- a/libraries/AP_NavEKF/AP_NavEKF.cpp
+++ b/libraries/AP_NavEKF/AP_NavEKF.cpp
@@ -214,7 +214,6 @@ NavEKF::NavEKF(const AP_AHRS *ahrs, AP_Baro &baro) :
     _ahrs(ahrs),
     _baro(baro),
     state(*reinterpret_cast<struct state_elements *>(&states)),
-    useCompass(true),           // activates fusion of airspeed data
     covTimeStepMax(0.07f),      // maximum time (sec) between covariance prediction updates
     covDelAngMax(0.05f),        // maximum delta angle between covariance prediction updates
     TASmsecMax(200),            // maximum allowed interval between airspeed measurement updates
@@ -444,7 +443,7 @@ void NavEKF::InitialiseFilterBootstrap(void)
     float yaw;
     Matrix3f Tbn;
     Vector3f initMagNED;
-    if (useCompass) {
+    if (use_compass()) {
         // calculate rotation matrix from body to NED frame
         Tbn.from_euler(roll, pitch, 0.0f);
 
@@ -669,7 +668,7 @@ void NavEKF::SelectMagFusion()
     readMagData();
 
     // determine if conditions are right to start a new fusion cycle
-    bool dataReady = statesInitialised && useCompass && newDataMag;
+    bool dataReady = statesInitialised && use_compass() && newDataMag;
     if (dataReady)
     {
         MAGmsecPrev = IMUmsec;
diff --git a/libraries/AP_NavEKF/AP_NavEKF.h b/libraries/AP_NavEKF/AP_NavEKF.h
index ee3b0afe9b..75ad6e3614 100644
--- a/libraries/AP_NavEKF/AP_NavEKF.h
+++ b/libraries/AP_NavEKF/AP_NavEKF.h
@@ -360,7 +360,6 @@ private:
     ftype dt;                       // time lapsed since the last covariance prediction (sec)
     ftype hgtRate;                  // state for rate of change of height filter
     bool onGround;                  // boolean true when the flight vehicle is on the ground (not flying)
-    const bool useCompass;          // boolean true if magnetometer data is being used
     Vector6 innovVelPos;            // innovation output for a group of measurements
     Vector6 varInnovVelPos;         // innovation variance output for a group of measurements
     bool fuseVelData;               // this boolean causes the velNED measurements to be fused