When you turn the airplane on first, it's receiver will do it's best ot work with the strongest signal it can find. It's really a dangerous thing to do if your airplane is an electric, and it's hard on any type airplane's servos. The receiver is not going to have a hard time finding signals.

With an electric, you really do not want the throttle suddenly arming nor the motor coming on full throttle unexpectedly.

Always turn on your TX first. And turn the TX off last. Always.