diff --git a/libraries/AP_NavEKF/AP_NavEKF_core.cpp b/libraries/AP_NavEKF/AP_NavEKF_core.cpp
index bd2bf00c96..f0af60c0ae 100644
--- a/libraries/AP_NavEKF/AP_NavEKF_core.cpp
+++ b/libraries/AP_NavEKF/AP_NavEKF_core.cpp
@@ -226,7 +226,7 @@ bool NavEKF_core::InitialiseFilterDynamic(void)
     InitialiseVariables();
 
     // get initial time deltat between IMU measurements (sec)
-    dtDelAng = dtIMUavg = 1.0f/_ahrs->get_ins().get_sample_rate();
+    dtDelAng = dtIMUavg = _ahrs->get_ins().get_loop_delta_t();
 
     // set number of updates over which gps and baro measurements are applied to the velocity and position states
     gpsUpdateCountMaxInv = (dtIMUavg * 1000.0f)/float(msecGpsAvg);
@@ -288,7 +288,7 @@ bool NavEKF_core::InitialiseFilterBootstrap(void)
     InitialiseVariables();
 
     // get initial time deltat between IMU measurements (sec)
-    dtDelAng = dtIMUavg = 1.0f/_ahrs->get_ins().get_sample_rate();
+    dtDelAng = dtIMUavg = _ahrs->get_ins().get_loop_delta_t();
 
     // set number of updates over which gps and baro measurements are applied to the velocity and position states
     gpsUpdateCountMaxInv = (dtIMUavg * 1000.0f)/float(msecGpsAvg);
@@ -3824,7 +3824,7 @@ void NavEKF_core::readIMUData()
     const AP_InertialSensor &ins = _ahrs->get_ins();
 
     // calculate the average time between IMU updates
-    dtIMUavg = 1.0f/(float)ins.get_sample_rate();
+    dtIMUavg = ins.get_loop_delta_t();
 
     // calculate the most recent time between gyro delta angle updates
     if (ins.get_delta_time() > 0.0f) {