diff --git a/libraries/SITL/SIM_Aircraft.cpp b/libraries/SITL/SIM_Aircraft.cpp
index d48a20c464..0f6a622ab6 100644
--- a/libraries/SITL/SIM_Aircraft.cpp
+++ b/libraries/SITL/SIM_Aircraft.cpp
@@ -17,12 +17,12 @@
   parent class for aircraft simulators
 */
 
-#include <AP_HAL/AP_HAL.h>
-#include <AP_Common/AP_Common.h>
 #include "SIM_Aircraft.h"
-#include <unistd.h>
-#include <sys/time.h>
+
 #include <stdio.h>
+#include <sys/time.h>
+#include <unistd.h>
+
 #ifdef __CYGWIN__
 #include <windows.h>
 #include <time.h>
diff --git a/libraries/SITL/SIM_Aircraft.h b/libraries/SITL/SIM_Aircraft.h
index 31990b5a31..1ab7eed190 100644
--- a/libraries/SITL/SIM_Aircraft.h
+++ b/libraries/SITL/SIM_Aircraft.h
@@ -20,10 +20,10 @@
 #ifndef _SIM_AIRCRAFT_H
 #define _SIM_AIRCRAFT_H
 
-#include "SITL.h"
-#include <AP_Common/AP_Common.h>
 #include <AP_Math/AP_Math.h>
 
+#include "SITL.h"
+
 namespace SITL {
 
 /*
diff --git a/libraries/SITL/SIM_Balloon.cpp b/libraries/SITL/SIM_Balloon.cpp
index 7799623f0f..e7d9896a76 100644
--- a/libraries/SITL/SIM_Balloon.cpp
+++ b/libraries/SITL/SIM_Balloon.cpp
@@ -17,8 +17,8 @@
   balloon simulator class
 */
 
-#include <AP_HAL/AP_HAL.h>
 #include "SIM_Balloon.h"
+
 #include <stdio.h>
 
 namespace SITL {
diff --git a/libraries/SITL/SIM_CRRCSim.cpp b/libraries/SITL/SIM_CRRCSim.cpp
index 1242f6919c..c42b372cde 100644
--- a/libraries/SITL/SIM_CRRCSim.cpp
+++ b/libraries/SITL/SIM_CRRCSim.cpp
@@ -17,10 +17,12 @@
   simulator connector for ardupilot version of CRRCSim
 */
 
-#include <AP_HAL/AP_HAL.h>
 #include "SIM_CRRCSim.h"
+
 #include <stdio.h>
 
+#include <AP_HAL/AP_HAL.h>
+
 extern const AP_HAL::HAL& hal;
 
 namespace SITL {
diff --git a/libraries/SITL/SIM_CRRCSim.h b/libraries/SITL/SIM_CRRCSim.h
index cb5d7d5da6..d8cd20c4fe 100644
--- a/libraries/SITL/SIM_CRRCSim.h
+++ b/libraries/SITL/SIM_CRRCSim.h
@@ -20,9 +20,10 @@
 #ifndef _SIM_CRRCSIM_H
 #define _SIM_CRRCSIM_H
 
-#include "SIM_Aircraft.h"
 #include <AP_HAL/utility/Socket.h>
 
+#include "SIM_Aircraft.h"
+
 namespace SITL {
 
 /*
diff --git a/libraries/SITL/SIM_Gazebo.cpp b/libraries/SITL/SIM_Gazebo.cpp
index 2349fda95a..4ace948951 100644
--- a/libraries/SITL/SIM_Gazebo.cpp
+++ b/libraries/SITL/SIM_Gazebo.cpp
@@ -17,10 +17,12 @@
   simulator connector for ardupilot version of Gazebo
 */
 
-#include <AP_HAL/AP_HAL.h>
 #include "SIM_Gazebo.h"
+
 #include <stdio.h>
 
+#include <AP_HAL/AP_HAL.h>
+
 extern const AP_HAL::HAL& hal;
 
 namespace SITL {
diff --git a/libraries/SITL/SIM_Gazebo.h b/libraries/SITL/SIM_Gazebo.h
index 0d43bf99a1..0336e238ae 100644
--- a/libraries/SITL/SIM_Gazebo.h
+++ b/libraries/SITL/SIM_Gazebo.h
@@ -20,9 +20,10 @@
 #ifndef _SIM_GAZEBO_H
 #define _SIM_GAZEBO_H
 
-#include "SIM_Aircraft.h"
 #include <AP_HAL/utility/Socket.h>
 
+#include "SIM_Aircraft.h"
+
 namespace SITL {
 
 /*
diff --git a/libraries/SITL/SIM_Gimbal.cpp b/libraries/SITL/SIM_Gimbal.cpp
index 2864b1abbe..62563c4bd7 100644
--- a/libraries/SITL/SIM_Gimbal.cpp
+++ b/libraries/SITL/SIM_Gimbal.cpp
@@ -17,10 +17,12 @@
   gimbal simulator class for MAVLink gimbal
 */
 
-#include "SIM_Aircraft.h"
 #include "SIM_Gimbal.h"
+
 #include <stdio.h>
 
+#include "SIM_Aircraft.h"
+
 extern const AP_HAL::HAL& hal;
 
 namespace SITL {
diff --git a/libraries/SITL/SIM_Gimbal.h b/libraries/SITL/SIM_Gimbal.h
index 949d3d613c..a820f586de 100644
--- a/libraries/SITL/SIM_Gimbal.h
+++ b/libraries/SITL/SIM_Gimbal.h
@@ -20,9 +20,10 @@
 #ifndef _SIM_GIMBAL_H
 #define _SIM_GIMBAL_H
 
-#include "SIM_Aircraft.h"
 #include <AP_HAL/utility/Socket.h>
 
+#include "SIM_Aircraft.h"
+
 namespace SITL {
 
 class Gimbal {
diff --git a/libraries/SITL/SIM_Helicopter.cpp b/libraries/SITL/SIM_Helicopter.cpp
index b6ab45468e..a051f21431 100644
--- a/libraries/SITL/SIM_Helicopter.cpp
+++ b/libraries/SITL/SIM_Helicopter.cpp
@@ -17,8 +17,8 @@
   helicopter simulator class
 */
 
-#include <AP_HAL/AP_HAL.h>
 #include "SIM_Helicopter.h"
+
 #include <stdio.h>
 
 namespace SITL {
diff --git a/libraries/SITL/SIM_JSBSim.cpp b/libraries/SITL/SIM_JSBSim.cpp
index 44be88518e..14ced10d6e 100644
--- a/libraries/SITL/SIM_JSBSim.cpp
+++ b/libraries/SITL/SIM_JSBSim.cpp
@@ -17,15 +17,16 @@
   simulator connector for ardupilot version of JSBSim
 */
 
-#include <AP_HAL/AP_HAL.h>
-
 #include "SIM_JSBSim.h"
-#include <stdio.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
+
 #include <arpa/inet.h>
 #include <errno.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+
+#include <AP_HAL/AP_HAL.h>
 
 extern const AP_HAL::HAL& hal;
 
diff --git a/libraries/SITL/SIM_JSBSim.h b/libraries/SITL/SIM_JSBSim.h
index 698ff276f5..1ed14869ba 100644
--- a/libraries/SITL/SIM_JSBSim.h
+++ b/libraries/SITL/SIM_JSBSim.h
@@ -20,9 +20,10 @@
 #ifndef _SIM_JSBSIM_H
 #define _SIM_JSBSIM_H
 
-#include "SIM_Aircraft.h"
 #include <AP_HAL/utility/Socket.h>
 
+#include "SIM_Aircraft.h"
+
 namespace SITL {
 
 /*
diff --git a/libraries/SITL/SIM_Multicopter.cpp b/libraries/SITL/SIM_Multicopter.cpp
index ef231e0692..c316eebc23 100644
--- a/libraries/SITL/SIM_Multicopter.cpp
+++ b/libraries/SITL/SIM_Multicopter.cpp
@@ -17,8 +17,8 @@
   multicopter simulator class
 */
 
-#include <AP_HAL/AP_HAL.h>
 #include "SIM_Multicopter.h"
+
 #include <stdio.h>
 
 namespace SITL {
diff --git a/libraries/SITL/SIM_Rover.cpp b/libraries/SITL/SIM_Rover.cpp
index cd35c0dacf..35a436ded2 100644
--- a/libraries/SITL/SIM_Rover.cpp
+++ b/libraries/SITL/SIM_Rover.cpp
@@ -17,9 +17,8 @@
   rover simulator class
 */
 
-#include <AP_HAL/AP_HAL.h>
 #include "SIM_Rover.h"
-#include <stdio.h>
+
 #include <string.h>
 
 namespace SITL {
diff --git a/libraries/SITL/SIM_Tracker.cpp b/libraries/SITL/SIM_Tracker.cpp
index bb54e2ef63..48cfce9c69 100644
--- a/libraries/SITL/SIM_Tracker.cpp
+++ b/libraries/SITL/SIM_Tracker.cpp
@@ -18,6 +18,7 @@
 */
 
 #include "SIM_Tracker.h"
+
 #include <stdio.h>
 
 namespace SITL {
diff --git a/libraries/SITL/SIM_last_letter.cpp b/libraries/SITL/SIM_last_letter.cpp
index 40a4dc411f..308cff0194 100644
--- a/libraries/SITL/SIM_last_letter.cpp
+++ b/libraries/SITL/SIM_last_letter.cpp
@@ -17,12 +17,14 @@
   simulator connector for ardupilot version of last_letter
 */
 
-#include <AP_HAL/AP_HAL.h>
 #include "SIM_last_letter.h"
-#include <stdio.h>
-#include <sys/types.h>
-#include <sys/stat.h>
+
 #include <fcntl.h>
+#include <stdio.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+
+#include <AP_HAL/AP_HAL.h>
 
 extern const AP_HAL::HAL& hal;
 
diff --git a/libraries/SITL/SIM_last_letter.h b/libraries/SITL/SIM_last_letter.h
index 5ded2f12f0..32c248ae33 100644
--- a/libraries/SITL/SIM_last_letter.h
+++ b/libraries/SITL/SIM_last_letter.h
@@ -20,9 +20,10 @@
 #ifndef _SIM_LAST_LETTER_H
 #define _SIM_LAST_LETTER_H
 
-#include "SIM_Aircraft.h"
 #include <AP_HAL/utility/Socket.h>
 
+#include "SIM_Aircraft.h"
+
 namespace SITL {
 
 /*
diff --git a/libraries/SITL/SITL.cpp b/libraries/SITL/SITL.cpp
index e83eac1ce6..bf076f6ffc 100644
--- a/libraries/SITL/SITL.cpp
+++ b/libraries/SITL/SITL.cpp
@@ -18,10 +18,11 @@
     SITL.cpp - software in the loop state
 */
 
+#include "SITL.h"
+
 #include <AP_Common/AP_Common.h>
 #include <AP_HAL/AP_HAL.h>
 #include <GCS_MAVLink/GCS_MAVLink.h>
-#include "SITL.h"
 
 extern const AP_HAL::HAL& hal;
 
diff --git a/libraries/SITL/SITL.h b/libraries/SITL/SITL.h
index a3b14bb5d7..8d0f2ac521 100644
--- a/libraries/SITL/SITL.h
+++ b/libraries/SITL/SITL.h
@@ -3,11 +3,8 @@
 #ifndef __SITL_H__
 #define __SITL_H__
 
-#include <AP_Param/AP_Param.h>
-#include <AP_Common/AP_Common.h>
-#include <AP_Math/AP_Math.h>
-#include <GCS_MAVLink/GCS_MAVLink.h>
 #include <DataFlash/DataFlash.h>
+#include <GCS_MAVLink/GCS_MAVLink.h>
 
 namespace SITL {