diff --git a/libraries/AP_AHRS/AP_AHRS_NavEKF.cpp b/libraries/AP_AHRS/AP_AHRS_NavEKF.cpp
index a2c6d6a37e..161a2a00ee 100644
--- a/libraries/AP_AHRS/AP_AHRS_NavEKF.cpp
+++ b/libraries/AP_AHRS/AP_AHRS_NavEKF.cpp
@@ -438,7 +438,7 @@ bool AP_AHRS_NavEKF::get_vert_pos_rate(float &velocity)
 
     case EKF_TYPE1:
     default:
-        EKF1.getPosDownDerivative(velocity);
+        velocity = EKF1.getPosDownDerivative();
         return true;
 
     case EKF_TYPE2: