Aviation Dictionary
سرعت دورانی مگنتوى موتور که برای تولید جرقه در سر شمع ها کافی باشد
The speed an electrical machine, such as a generator or magneto, must be turned for it to produce its rated output. In a magneto, the coming-in speed is the lowest speed at which the magneto produces enough voltage to fire all the spark plugs consistently.