diff --git a/src/modules/fw_att_pos_estimator/estimator.cpp b/src/modules/fw_att_pos_estimator/estimator.cpp
index 9b57dfd550..f2db4aa1ed 100644
--- a/src/modules/fw_att_pos_estimator/estimator.cpp
+++ b/src/modules/fw_att_pos_estimator/estimator.cpp
@@ -322,7 +322,7 @@ void CovariancePrediction()
     float SF[14];
     float SG[8];
     float SQ[11];
-    float SPP[13];
+    float SPP[13] = {0};
     float nextP[21][21];
 
     // calculate covariance prediction process noise