Your fail safe settings should be throttle off. 

 

To check it, turn the airplane and transmitter on. Confirm surface control. Set the throttle to mid. Turn the transmitter off. After a couple seconds the throttle should close. Now, you electric guys do this with a helper to secure the airplane. With the motor running (no more than 50%) turn the transmitter off. 

 

If your motor doesn’t stop or the throttle doesn’t close, re-bind the receiver to your radio. 

 

None of your program settings will be affected. 

 

This fail safe setting is what prevents an airplane from flying away. If the link is lost in flight the motor or engine will shut down. It will also prevent a power up on the ground if you accidentally turn the transmitter off first. 

 

Always fly inside our boundaries.