diff --git a/libraries/AP_NavEKF2/AP_NavEKF2_MagFusion.cpp b/libraries/AP_NavEKF2/AP_NavEKF2_MagFusion.cpp
index fed0a152cc..f00aa8dba8 100644
--- a/libraries/AP_NavEKF2/AP_NavEKF2_MagFusion.cpp
+++ b/libraries/AP_NavEKF2/AP_NavEKF2_MagFusion.cpp
@@ -342,7 +342,7 @@ void NavEKF2_core::FuseMagnetometer()
     Vector3f &MagPred = mag_state.MagPred;
     ftype &R_MAG = mag_state.R_MAG;
     ftype *SH_MAG = &mag_state.SH_MAG[0];
-    Vector24 H_MAG;
+    Vector24 H_MAG {};
     Vector6 SK_MX;
     Vector6 SK_MY;
     Vector6 SK_MZ;