diff --git a/libraries/AP_NavEKF2/AP_NavEKF2_Control.cpp b/libraries/AP_NavEKF2/AP_NavEKF2_Control.cpp
index 1cc633a922..5314ab2f6c 100644
--- a/libraries/AP_NavEKF2/AP_NavEKF2_Control.cpp
+++ b/libraries/AP_NavEKF2/AP_NavEKF2_Control.cpp
@@ -240,8 +240,8 @@ void NavEKF2_core::setAidingMode()
             }
             posAidLossCritical = (imuSampleTime_ms - lastRngBcnPassTime_ms > maxLossTime_ms) &&
                    (imuSampleTime_ms - lastPosPassTime_ms > maxLossTime_ms);
-            posAidLossPending = (imuSampleTime_ms - lastRngBcnPassTime_ms > frontend->_gsfResetDelay) &&
-                    (imuSampleTime_ms - lastPosPassTime_ms > frontend->_gsfResetDelay);
+            posAidLossPending = (imuSampleTime_ms - lastRngBcnPassTime_ms > (uint32_t)frontend->_gsfResetDelay) &&
+                    (imuSampleTime_ms - lastPosPassTime_ms > (uint32_t)frontend->_gsfResetDelay);
         }
 
         if (attAidLossCritical) {