I fly combat and crashing is inevitable. With a timer when I crash does it turn off or does it ruin my esc or battery or timer?One guy just uses and rc receiver and the controller. Pros and cons.

I have wondered this same thing. I had my Stuka stunt ship nose over in high, wet grass and was using the ESC current setting at normal, it tried to flip the ship over before cutting out and smoking the motor. After looking at the setting there are two current setting in the Castle Creation ESP, one on current limit and the second current cutoff type. The Current limit can be set to sensitive but that won't do it (that's were I had mine at) you have to set the Current Cutoff Type to Hard Cutoff. The cutoff type is important, if you leave it as Soft it takes a longer time to shut down the motor and can smoke in a prop stop crash. I have not tried any of the timer cutoffs but even with them I would set the ESP to sensitive and hard cutoff.

Best,    DennisT