diff --git a/libraries/RC_Channel/RC_Channel_aux.cpp b/libraries/RC_Channel/RC_Channel_aux.cpp
index d6d24f5815..e423c0d498 100644
--- a/libraries/RC_Channel/RC_Channel_aux.cpp
+++ b/libraries/RC_Channel/RC_Channel_aux.cpp
@@ -12,7 +12,7 @@ const AP_Param::GroupInfo RC_Channel_aux::var_info[] PROGMEM = {
     // @Param: FUNCTION
     // @DisplayName: Servo out function
     // @Description: Setting this to Disabled(0) will setup this output for control by auto missions or MAVLink servo set commands. any other value will enable the corresponding function
-    // @Values: 0:Disabled,1:RCPassThru,2:Flap,3:Flap_auto,4:Aileron,6:mount_pan,7:mount_tilt,8:mount_roll,9:mount_open,10:camera_trigger,11:release,12:mount2_pan,13:mount2_tilt,14:mount2_roll,15:mount2_open,16:DifferentialSpoiler1,17:DifferentialSpoiler2,18:AileronWithInput,19:Elevator,20:ElevatorWithInput,21:Rudder,24:Flaperon1,25:Flaperon2,26:GroundSteering,27:Parachute,28:EPM,29:LandingGear
+    // @Values: 0:Disabled,1:RCPassThru,2:Flap,3:Flap_auto,4:Aileron,6:mount_pan,7:mount_tilt,8:mount_roll,9:mount_open,10:camera_trigger,11:release,12:mount2_pan,13:mount2_tilt,14:mount2_roll,15:mount2_open,16:DifferentialSpoiler1,17:DifferentialSpoiler2,18:AileronWithInput,19:Elevator,20:ElevatorWithInput,21:Rudder,24:Flaperon1,25:Flaperon2,26:GroundSteering,27:Parachute,28:EPM,29:LandingGear,30:EngineRunEnable
     // @User: Standard
     AP_GROUPINFO("FUNCTION",       1, RC_Channel_aux, function, 0),
 
diff --git a/libraries/RC_Channel/RC_Channel_aux.h b/libraries/RC_Channel/RC_Channel_aux.h
index d5fa35ba5c..d6791c7e5b 100644
--- a/libraries/RC_Channel/RC_Channel_aux.h
+++ b/libraries/RC_Channel/RC_Channel_aux.h
@@ -69,6 +69,7 @@ public:
         k_parachute_release     = 27,            ///< parachute release
         k_epm                   = 28,            ///< epm gripper
         k_landing_gear_control  = 29,            ///< landing gear controller
+        k_engine_run_enable     = 30,            ///< engine kill switch, used for gas airplanes and helicopters
         k_nr_aux_servo_functions         ///< This must be the last enum value (only add new values _before_ this one)
     } Aux_servo_function_t;