Battery failure = crash
#16
To help eliminate these runaways use a dedicated built battery pack for your receiver and servos. Most receiver packs are also 6volts so that you have better servo control from the start, and you don't run the risk of single cell falling out of the holder. I also will use throttle servos that don't require a huge spring or rubber band to return to neutral if the car goes deadstick. Some servos on the market require very little effort to return to neutral, and some require a fair amount of torque. Buying a more expensive servo with a lighter action on deadstick ... is a worthwhile investment.