diff --git a/libraries/AP_Airspeed/AP_Airspeed_NMEA.cpp b/libraries/AP_Airspeed/AP_Airspeed_NMEA.cpp
index cac1c54727..36341c8cd8 100644
--- a/libraries/AP_Airspeed/AP_Airspeed_NMEA.cpp
+++ b/libraries/AP_Airspeed/AP_Airspeed_NMEA.cpp
@@ -26,6 +26,7 @@
 #if APM_BUILD_TYPE(APM_BUILD_Rover) || APM_BUILD_TYPE(APM_BUILD_ArduSub) 
 
 #include "AP_Airspeed.h"
+#include <AP_SerialManager/AP_SerialManager.h>
 
 #define TIMEOUT_MS 2000
 
diff --git a/libraries/AP_Airspeed/AP_Airspeed_NMEA.h b/libraries/AP_Airspeed/AP_Airspeed_NMEA.h
index 47d5ed7b6f..480637799f 100644
--- a/libraries/AP_Airspeed/AP_Airspeed_NMEA.h
+++ b/libraries/AP_Airspeed/AP_Airspeed_NMEA.h
@@ -11,7 +11,6 @@
 
 #include "AP_Airspeed_Backend.h"
 #include <AP_HAL/AP_HAL.h>
-#include <AP_SerialManager/AP_SerialManager.h>
 
 class AP_Airspeed_NMEA : public AP_Airspeed_Backend
 {