diff --git a/ArduCopter/APM_Config.h b/ArduCopter/APM_Config.h
index b7db6c5ca7..d614e4b6ab 100644
--- a/ArduCopter/APM_Config.h
+++ b/ArduCopter/APM_Config.h
@@ -41,6 +41,7 @@
 //#define PRECISION_LANDING     ENABLED             // enable precision landing using companion computer or IRLock sensor
 //#define GNDEFFECT_COMPENSATION ENABLED            // enable ground effect compensation for barometer (if propwash interferes with the barometer on the ground)
 //#define CAL_ALWAYS_REBOOT                         // flight controller will reboot after compass or accelerometer calibration completes
+//#define DISALLOW_GCS_MODE_CHANGE_DURING_RC_FAILSAFE   // disable mode changes from GCS during Radio failsafes.  Avoids a race condition for vehicle like Solo in which the RC and telemetry travel along the same link
 
 // other settings
 //#define THROTTLE_IN_DEADBAND   100                // redefine size of throttle deadband in pwm (0 ~ 1000)