diff --git a/Blimp/AP_Arming.cpp b/Blimp/AP_Arming.cpp
index dc3e3a21d2..06889471ff 100644
--- a/Blimp/AP_Arming.cpp
+++ b/Blimp/AP_Arming.cpp
@@ -244,7 +244,7 @@ bool AP_Arming_Blimp::pre_arm_ekf_attitude_check()
 bool AP_Arming_Blimp::mandatory_gps_checks(bool display_failure)
 {
     // always check if inertial nav has started and is ready
-    const AP_AHRS_NavEKF &ahrs = AP::ahrs_navekf();
+    const auto &ahrs = AP::ahrs();
     char failure_msg[50] = {};
     if (!ahrs.pre_arm_check(false, failure_msg, sizeof(failure_msg))) {
         check_failed(display_failure, "AHRS: %s", failure_msg);
@@ -363,7 +363,7 @@ bool AP_Arming_Blimp::arm(const AP_Arming::Method method, const bool do_arming_c
 
     gcs().send_text(MAV_SEVERITY_INFO, "Arming motors"); //MIR kept in - usually only in SITL
 
-    AP_AHRS_NavEKF &ahrs = AP::ahrs_navekf();
+    auto &ahrs = AP::ahrs();
 
     blimp.initial_armed_bearing = ahrs.yaw_sensor;
 
@@ -425,7 +425,7 @@ bool AP_Arming_Blimp::disarm(const AP_Arming::Method method, bool do_disarm_chec
     gcs().send_text(MAV_SEVERITY_INFO, "Disarming motors"); //MIR keeping in - usually only in SITL
 
 
-    AP_AHRS_NavEKF &ahrs = AP::ahrs_navekf();
+    auto &ahrs = AP::ahrs();
 
     // save compass offsets learned by the EKF if enabled
     Compass &compass = AP::compass();
diff --git a/Blimp/Blimp.h b/Blimp/Blimp.h
index 04d39599c3..f8ca967bd8 100644
--- a/Blimp/Blimp.h
+++ b/Blimp/Blimp.h
@@ -44,7 +44,7 @@
 #include <Filter/Filter.h>             // Filter library
 #include <AP_Airspeed/AP_Airspeed.h>        // needed for AHRS build
 #include <AP_Vehicle/AP_Vehicle.h>         // needed for AHRS build
-#include <AP_InertialNav/AP_InertialNav.h>     // ArduPilot Mega inertial navigation library
+#include <AP_InertialNav/AP_InertialNav_NavEKF.h>     // ArduPilot Mega inertial navigation library
 #include <AP_RCMapper/AP_RCMapper.h>        // RC input mapping library
 #include <AP_BattMonitor/AP_BattMonitor.h>     // Battery monitor library
 #include <AP_Arming/AP_Arming.h>
diff --git a/Blimp/Log.cpp b/Blimp/Log.cpp
index dc5915e7a8..e107898cfb 100644
--- a/Blimp/Log.cpp
+++ b/Blimp/Log.cpp
@@ -98,7 +98,7 @@ void Blimp::Log_Write_Attitude()
 // Write an EKF and POS packet
 void Blimp::Log_Write_EKF_POS()
 {
-    AP::ahrs_navekf().Log_Write();
+    AP::ahrs().Log_Write();
     ahrs.Write_AHRS2();
 #if CONFIG_HAL_BOARD == HAL_BOARD_SITL
     sitl.Log_Write_SIMSTATE();