diff --git a/ArduPlane/defines.h b/ArduPlane/defines.h
index 4b2b7f30a7..39b950e63e 100644
--- a/ArduPlane/defines.h
+++ b/ArduPlane/defines.h
@@ -224,6 +224,7 @@ enum gcs_severity {
 
 #define CONFIG_INS_OILPAN 1
 #define CONFIG_INS_MPU6000 2
+#define CONFIG_INS_STUB 3
 
 #define AP_BARO_BMP085   1
 #define AP_BARO_MS5611   2